Question: Earliest feature of radiation toxicity is

Ans. a (Erythema). (Ref. Harrison, Principles of Medicine, 15th ed., 2562).RADIATION TOXICITY TO SKIN# Skin reaction can be seen with two weeks of fractionated radiotherapy (RT).# Erythema is the earliest observed feature followed by desquamation (dry/moist).# Chronic reaction can be seen starting at 6-12 months after irradiation.# Atrophic, easily damageable epidermis, hyperpigmentation, thin skin with hair loss also occur.# Rarely malignant change can occur.Educational points:Low-energy ORTHOVOLTAGE beams (150 to 400 kV) scatter when they strike the body, much like light diffuses when it strikes particles in the air resulting in more damage to adjacent normal tissues and less radiation delivered to the tumor.MEGAVOLTAGE radiation (1 MeV) has very low lateral scatter; this produces# a skin-sparing effect,# more homogeneous distribution of the radiation energy, and greater deposit of the energy in the tumor, or target volume.


Question: The most common brain tumor is

Most common Brain tumors are Secondaries or metastasis Most Common primary Brain tumor is a Meningioma Most common intraparenchymal Brain tumor is Glioma Most common calcifying Brain tumors is Craniopharyngioma Most common intraparenchymal calcifying Brain tumors is Oligodendroglioma


Question: Ring sign with dilated bronchi on CXR is a feature of

(B) Bronchiectasis # RADIOGRAPHIC FEATURES of BRONCHIECTASIS> Plain film: Chest x-rays are usually abnormal, but are inadequate in the diagnosis or quantification of bronchiectasis. Tram-track opacities are seen in cylindrical bronchiectasis, and air-fluid levels may be seen in cystic bronchiectasis.> Overall there appears to be an increase in bronchovascular markings, and bronchi seen end on may appear as ring shadows 8.> Pulmonary vasculature appears ill-defined, thought to represent peribronchovascular fibrosis 8-9.> CT: CT and HRCT especially excels at demonstrating the airways, and is able to a greater or lesser degree to distinguish some of the various underlying causes.> A number of features are helpful in diagnosing bronchiectasis 8-9; Bronchus visualised within 1 cm of pleural surface Especially true of lung adjacent to costal pleura Most helpful sign for early cylindrical change Lack of tapering Increased bronchoarterial ratio Diameter of a bronchus should measure approximately 0.65 -1.0 times that of the adjacent pulmonary artery branch Between 1 and 1.5 may be seen in normal individuals, especially those living at high altitude Greater than 1.5 indicates bronchiectasis> A number of ancillary findings are also recognised: Bronchial wall thickening: normally wall of bronchus should be less than half the width of accompanying pulmonary artery branch Mucoid impaction Air-trapping and mosaic perfusion> Signs described on CT include: Tram-track sign Signet ring sign String of pearls sign Cluster of grapes sign


Question: Not a radiological finding of scurvy


Question: Ionization radiation acts on tissue leading to

B i.e. Excitation of electron from orbit


Question: Radio iodine is used in treatment of


Question: Collar button sign is associated with

"Collar button ulcers" are manifestations of inflammatory processes within the bowel, seen with Ulcerative colitis.


Question: Missed IUD (IUCD) is recognized by


Question: Dense calcification is seen in

B i.e. Chondrosarcoma - Most common bone tumor = Osteochondroma Bone tumor with Dense calcification = Chondro Sarcoma Bone tumor with Calcified secondaries = Osteosarcoma


Question: Investigation of choice for torsion testis is

Ans: a) Colour Doppler [ Ref:- Sutton - 7th edition Page No:-Doppler ultrasound is the imaging of choice for torsion testis. It helps in the diagnosis of torsion by virtue of reduced vascularity ( absence or poor colour flow, reduced peak systolic velocities) compared with the unaffected side.


Question: A Gamma camera is used for

Gamma Camera (Aka Scintillation Camera or Anger Camera) It is used to image gamma radiation emitting radioisotopes.
This technique is known as scintigraph.
Gamma camera is able to detect and make images from the very small amounts of ionising radiation emitted from patients having a nuclear medicine study.
The gamma camera detects radioactive energy that is emitted from the patient's body and converts it into an image.
The gamma camera does not emit any radiation.
The gamma camera is composed of radiation detectors, called gamma camera heads.
The most common type of gamma camera is the single-headed system.
it consists of a gamma camera detector mounted on a gantry that allows the camera head to be positioned in a flexible way over different regions of the patient’s body.
Dual-headed gamma cameras are becoming increasingly popular.
In these systems, two gamma camera heads are mounted onto the gantry.
Also Note: SPECT involves the rotation of the gamma camera heads around the patient's body to produce more detailed, three-dimensional images.

To image radioactivity emitted from organs


Question: Not a Radiological sign of Ulcerative colius

Raspberry / rose thorm appearance is seen in crohn's disease.


Question: Fraying of anterior ends of ribs is seen in


Question: Emergency radiotherapy is given in

Note the swelling of his face first thing in the morning (left) and its resolution after being upright all day (right). Specialty. Pulmonology.
Superior vena cava syndrome (SVCS), is a group of symptoms caused by obstruction of the superior vena cava
(a short, wide vessel carrying circulating blood into the heart).


Question: Not a Radiological finding of pericardial effusion

Dock's sign (inferior notching of 3-8 ribs).
Seen in coarctation of aorta.


Question: Vesicoureteric reflux is demonstrated by using


Question: Geographic lytic lesions in vault of skull with bevelled edges are seen with

B i.e. Eosinophillic Granuloma Features Disorder Geographic lytic skullQ Eosinophillic granuloma/Hand? Veebrae planaQ Schuller Christian ds/ Histocytosis


Question: High resolution computed tomography of the chest is the ideal modality for evaluating

B i.e. Interstitial Lung disease Routine chest CT examinations consists of adjacent 8-10 mm sections through the area of interest. Intravenous contrast medium may be injected when the primary purpose of examination is to show the mediastinum or hilar structures. High resolution CT (HRCT) uses very thin 1-2 mm thick.Q HRCT of lung is designed primarly to diagnose : - BronchiectasisQ - Interstial Lung diseaseQ as fibrosing alveolitis, asbestosis etc. - When lung biopsy is required, HRCT is useful for determining most appropriate area from which biopsy sample should be taken.


Question: Floating teeth sign is seen in

Radiological features of Langerhans cell histiocytosis : Punched out lytic lesions of skull with bevelled edges. Geographic skull. Floating teeth sign due to radiolucent lesion around the teeth. Veebra plana


Question: Tripple bubble sign is seen in

CHPS - Single bubble sign
Duodenal atresia - Double bubble sign
Jejunal atresia - Triple bubble sign
Ileal atresia - Multiple bubble sign.


Question: Flowing Candle Wax appearance seen in

Dripping candle wax sign, also known as flowing candle wax appearance, describes the appearance of sclerotic coical thickening in melorheostosis/LERI disease. The irregular coical hyperostosis typically occurs on one side of the involved bone and undulates along much like melted wax down a candle.


Question: IOC for removascular hypertension

IOC for Renovascular hypertension - MR angio.
Catopril renal scintigraphy - preferred screening test.
Spiral CT : Most sensitive and specific screening (after angio).


Question: The fundamental particle present in protons is


Question: Mathematical representation of inverse square law is


Question: Not a Radiological feature of achalasia cardia

Antral nipple sign - Feature of Congenital hypertrophic pyloric Stenosis.


Question: Continuous diaphragm sign is seen in

Air collects beneath the pericardium so the central part of diaphragm become visible represents pneumo mediastinium.


Question: Sunray/ spoke wheel vasculature is a feature of

On DSA- The classic angiographic appearance of a meningioma is a radial "sunburst" of vessels extending from the base of the tumor toward its periphery. Dural vessels supply the core or center of the lesion, radiating outward from the vascular pedicle of the tumor. DSA image showing characteristic SUNBURST PATTERN of meningioma. Mother in law sign- Lesions that enhance early during the aerial phase and remain opacified well after the venous phase and is seen in meningioma. Other Features of Meningioma Dural tail sign Hyperdense on CT Isointense/Hypointense on T2 Calcification Skeletal Hyperostosis Pneumosinus dilatans


Question: Optimal Doppler angle should be

Ideal Doppler Angle for color doppler is 0 degrees ,Most blood vessels course parallel to the skin and zero Doppler angle is seldom obtainable. In addition, no Doppler shift is obtained at 90 degrees since the cosine of 90 degrees is 0. Thus, the optimal Doppler angle lies between 45 and 60 degrees.


Question: Thickness of lead apron is


Question: Preoperative investigation to be done in down's syndrome posted for surgery

Endocardial cushion defect is most commonly present in Down's syndrome patient.
Echo is done prior.


Question: Radioactive iodine for thyroid carcinoma is given by

Radioactive iodine (131-I) is a radioactive isotope that is administered orally, in a liquid or capsule form.Thyroid tissue concentrates iodine. For this reason, 131I can be given in order to deliver tumoricidal doses of radioactivitydirectly to thyroid tissue, both benign and malignant. In the setting of thyroid cancer, all normal tissue should be removed (total thyroidectomy) along with any gross neck disease (neck dissection) in order for any residual microscopic disease or distant metastases to receive an optimal dose.(Ref: Practical Management of Thyroid Cancer: A Multidisciplinary ApproachErnest L. Mazzaferri et al, page 22)Bailey and Love 27e pg: 819


Question:
Among the natural radiation, the one that contributes to
more radiation exposure of general population

The general population is exposed to radiation primarily from natural background and medical sources.
Radon and its decay products may become attached to dust particles that can be inhaled and deposited on the bronchial epithelium in the respiratory tract. Radon is estimated to be responsible for approximately 73% of the background exposure of the world’s population.
Key Concept


Question: Not a radiological feature of scleroderma

Bullet shaped vertebra is seen in Achondroplasia.


Question: Stratosphere sign is seen in


Question: Thyroid dose from panoramic radiography is about


Question: Most appropriate initial method of investigation for carcinoma head of pancreas

(A) EUS guided Transgastric biopsy [?]Endoscopic Ultrasonography (EUS):EUS can image the primary cancer and be a means of obtaining a FNA of pancreatic adenocarcinoma.When a mass cannot be visualized on CT scan, sonography through the wall of the stomach or duodenum can image tumors in the body or tail and head of the pancreas, respectively.Suspicious lesion by imaging should be treated with resection.In specific patients a tissue diagnosis may be needed, such as in patients entering a clinical trial, prior to neoadjuvant therapy, and prior to chemotherapy in advanced tumors (EUS can be highly accurate).EUS has a sensitivity for histologic diagnosis of 91% with a specificity of 100% with a pancreatic mass.Other Options[?]Multiphase Multidetector Helical Computerized Axial Tomography:Among diagnostic imaging techniques, abdominal CT scanning is the most common for confirming suspected pancreatic malignancy.Standard CT techniques are relatively insensitive for the assessment of resectability.Vascular involvement & liver metastases can be most optimally assessed with newer CT imaging techniques.Cornerstone of diagnostic evaluation of a pancreatic tumor is the multiphase CT scan, with i.v. contrast CT through pancreas during arterial, portal venous, & parenchymal phases of enhancement.[?]Magnetic Resonance Imaging:To date, MRI has not been widely used to assess pancreatic cancer.This method was initially limited by long scanning times and the resultant artifact caused by organ motion.Dynamic MRI, with i.v. contrast enhance have sensitivity & specificity comparable to those for helical CT.Some found MRI more accurate at predicting malignancy of the pancreatic duct due to findings of concurrent MRI cholangiopancreatography, but use of this imaging method for pancreatic cancer is currently not widespread.[?]Staging Laparoscopy:Laparoscopy & multiphase CT have evolved concurrently as methods to evaluate a pancreatic mass.Both have emerged as highly effective in evaluating the tumors, but CT as a noninvasive modality supplants the use of routine laparoscopy.Laparoscopy that precedes planned resection can accurately identify metastases that avoid detection by CT, and when combined with laparoscopic ultrasound, can delineate vascular invasion as well as metastases within the hepatic parenchyma.Currently, routine use of laparoscopy is not warranted.Few patients will have findings on laparoscopy that add to information found at CT scanning.The group at JHMI retrospectively reviewed 188 cases of patients studied preoperatively using CT and treated through a laparotomy.Preoperative laparoscopy would have benefited a maximum of 2.3% of patients with a pancreatic head tumor.Lesions in the body and tail were more likely to have misleading CT scans (35.3%).American Hepato-Pancreato-biliary Association recommends laparoscopy be limited to select patients with primary tumors greater than 3 cm in diameter, body or tail tumors, equivocal findings of metastasis on CT, & CA19-9 level greater than 100U/mL.Using these criteria, the subset of patients with advanced tumors not identified on CT scan can be accurately assessed by laparoscopy.


Question: Pulmonary embolism is best diagnosed by

D i.e. CT Scan Investigation of choice (IOC) is CT angiography (contrast CT) followed by pulmonary aeriography followed by a ventilation - perfusion scanQ. Advantages & Disadvantages of various tests for DTE Dx Test Advantages Disadvantages 1. Plasm D-dimer ELISA Normal results make PE highly unlikely Level is elevated in various systemic illnesses 2. Lung (V-P) Scanning Standard initial imaging test for Most scans are neither high probability nor PEQ. High probability scans are reliable for detecting PE normal/near normal scans are reliable for precluding PE normal/near normal; most are equivocal 3. Pulmonary angiography Gold standard for diagnosisQ Invasive, Costly & Uncomfoable ; so not a first line investigation 4. CT angiography (helical) - Noninvasive, widely available test - Initially it was a sensitive method of that has replaced pulmonary detecting central segmental, lobar & main angiography (conventional) as the pulmonary aery emboli upto 4th order vessel main stay investigation for PEQ. (-- 7mm diameter) i.e., from aoic arch to - Stratifies risk, obtains images of inferior pulmonary vein. However, with RV & LV advent of helical & multidetector CT (MDCT) has improved resolution of peripheral aeries upto 6th order.


Question: Lacunar skull is a radiological feature of

Lacunar skull - Arnold chiari malformation.
Cotton wool skull - Paget's disease.
Geographic skull - Eosinophilic granuloma.


Question: Champagne glass pelvic inlet is seen in

Achondroplasia

Trident hand
Champagne glass pelvic inlet
Bullet vertebra.


Question: Pop corn calcification is a characteristic of

Pop corn calcification is characteristic of pulmonary hamartoma.


Question: The recommended monthly limit to the fetus is

The NCRP recommends a monthly limit of 0.5 mSv (50 mrem) to the embryo or fetus once a woman declares her pregnancy. In contrast to this, the ICRP recommends a limit of 2 mSv (200 mrem) to the surface of the woman&;s abdomen (lower trunk) for the remainder of the pregnancy. These recommendations are essentially similar and are designed to limit the risk of mental retardation, other congenital malformations, and carcinogenesisReference: Eric J Hall Textbook of Radiobiology for Radiologist; 5th edition


Question: Not a radiological finding of Hemophilic arthropathy

Knee intercondylar notch widening is seen in Hemophilia.

Shortening of intercondylar notch of knee


Question: "Square root sign" is a radiological finding of

"Square root sign" - Contrictive pericorditis.
Ground glass ventricular septum - HOCM.


Question: Not a radiological feature of rickets

Ans. c (Subluxation of epiphysis) (Ref. RRM 6th ed., 156)RICKETS# Faulty mineralization of the bone before the fusion of growth plate, i.e., during enchondral bone growth, is known as RICKETS.# Histo: zone of maturation has an increase in number of maturing cartilage cells with loss of normal columnar arrangement; zone of preparatory calcification does not form; failure of osteoid mineralization also in shafts so that osteoid production elevates periosteum.# Location: Metaphyses of long bones subjected to stress are particularly involved (wrist, ankles, knees)# X-rav features:- Widening and lengthening of growth plate (zone of provisional calcification affected) is earliest radiographic feature of rickets.- Reaction of periosteum may occur - - Indistinct cortex - Coarse trabeculation - Knees + wrists + ankles mainly affected - Rickets- Epiphyseal plates widened + irregular - Tremendous metaphysis (fraying, splaying, cupping) - Spur (metaphyseal) - Additional features: --- * Bowing of long bones* Genu recurvatum* At costochondral junction, epiphyseal widening results in typical 'rachitic rosary'* Frontal bossing* Scoliosis* Slipped capital femoral epiphysis* Triradiate pelvis* Basilar invaginationEducational point:D/d of Frayed Metaphyses# Congenital infections (rubella, syphilis)# Hypophosphatasia # Achondroplasia # RicketsMnemonic: CHARMS# Metaphyseal dysostosis # Scurvy The radiological features of scurvy1)Spurs (Pelkan Spur)Metaphyseal spurs projecting at right angles to axis of shaft2)Subperiosteal hemorrhagesDiaphyseal subperiosteal hematoma with calcification of elevated periosteum is the sure sign of healing (woody-leg)3)Cortical thinning"Pencil-thin" cortex4)Corner sign of ParkeSubepiphyseal infarction or comminution causing mushrooming or cupping of epiphysis5)5)OsteoporosisCharacteristically "ground-glass" osteoporosis6)Rarefaction zone of TrummerfeldMetaphyseal radiolucent zone on shaft side7)White line of FrankelMetaphyseal zone of provisional/preparatory calcification also seen in lead or phosphorus or bismuth poisoning and in healing rickets8)Wimberger's signSclerotic ring seen around the low-density osteopenic epiphysis


Question: Iridium 192 half life

Ans. (c) 74 daysRef: Basic radiological physics 2nd ed. /180* Iridium-192, emits gamma rays. It has energy of 0.4MeV.* Tl/2 of iridium 192: 74 daysImportant Half Life of Radionuclides* Gold-198: 2.7 days* Iodine- 123: 13.3 hours* Iodine-131: 8 days* Phosphorus-32: 14.3 days* Yttrium 90: 64 hours* Cobalt-60: 5.26 years* Caesium-137: 30 years* Radium-226: 1620 years


Question: Maximum damage to skin is caused by

Ans. c (Orthovoltage X-ray) (Ref. Harrison's medicine 17th ed. 484)# External Beam therapy unit includea. X-ray machine orb. Teletherapy unit (i.e. Linear Acclerator or Cobalt-60 unit)# Beams used for external radiotherapy are# X-ray beams:a. Conventionalb. Superficial: 40 to 120 kVc. Orthovoltage: 250 to 400 kVd. Megavoltage: (> 1Mv) - 2, 4, 6, 12 & 35 MeV# Gamma ray beams:a. Cobalt -60 beamb. Cesium -137 beam# Particle beams:a. Electronsb. Protonsc. NeutronsThus routine radio-therapy treatment is by X-ray beams in the super voltage or mega voltage range.# Orthovoltage or deep X-ray therapy machine produce X-rays with a voltage of 200-300 kV.# For many years they were the most powerful machines in radiotherapy and were used to irradiate most sites, however now been replaced by megavoltage equipments because of following advantages of megavoltage therapy (2 to 8 million volts);# Skin sparing effects: With orthovoltage X-rays maximum dose is received by skin surface whereas with high voltagesmaximum dose is at some distance beneath skin, the skin is thus spared with high dose.# Greater penetration of beam# Differential absorption in tissues# Improved collimation


Question: Honey comb lung appearance is seen in

Honey comb lung
Histiocytosis-x, scleroderma, Rheumatoid arthritis, ILD, TB.


Question: Saw tooth appearance on barium study is seen in

Diveiculosis Saw-tooth appearance to the colon, usually sigmoid, with shoening of the bowel, crowding of haustra and picket-fencing of folds Ischemic colitis - thumb printing sign.


Question: Sestamibi Scan is used in


Question: Most common endocrine complication of intracranial radiotherapy is

Growth hormone deficiency is M/c endocrine complication.


Question: Goose neck deformity is seen in

Ileocecal TB: Goose neck deformity occurs due to contracted, cicatrized, and pulled-up cecum as well as straightening of the terminal ileum.


Question: The minimum amount of tooth demineralization required for radiographic detection of dental caries is

Lesions confined to enamel may not be evident until approximately 30% to 40% demineralization has occurred. For this reason, the actual depth of penetration of a carious lesion is often deeper than seen in the image.

Oral radiology by White & Pharaoh 7th ed. Page no 288


Question: Investigation not useful in Multiple Myeloma

The Bone scan is a nuclear scan done using Tc99m-MDP and shows a hot spot in areas of osteoblastic activity. As Multiple myeloma has osteolytic metastasis, So bone scan is not sensitive for detecting these bone mets and usually appear as cold areas Multidetector CT (MDCT) is more sensitive in detecting Myeloma and a low-dose technique can be used to limit radiation to the patient


Question: Calcification of Posterior Longitudnal Ligament is best diagnosed by

* Calcifications are best seen on CT Scan images. * Calcification of Posterior Longitudnal Ligament is (OPLL) Ossified Posterior Longitudnal Ligament and was traditionally considered more frequent in Japan and common in cervical spine Figure: Illustration of OPLL Figure: OPLL On plain film Figure: OPLL on sagittal CT scan Calcification of Posterior Longitudnal Ligament is also known as Japan's Disease.


Question: Most radiosensitive among the following is

(D) Nucleosomal DNA > Among the factors contributing to the distribution of DNA damage within irradiated mammalian cell nuclei are the interactions of DNA with nuclear proteins and the formation of multi-molecular chromatin structures. Studies on the manipulation of chromatin structures of isolated nuclei are summarised.> The majority of chromatin within the nucleus of living cells is tightly compacted into nucleosomal superhelices and other higher order structures which have a limited ability to be damaged by radiation.> The treatment of isolated nuclei with hypotonic buffers causes a decondensation of these structures and markedly sensitises the DNA to radiation, while retaining the majority of the chromosomal proteins


Question: Radiological investigation of female of reproductive age group is restricted to

B i.e. First ten days of M.C. Ten day Rule : Radiological investigation in a reproductive age gp. female should be carried out within 10 days of last Menstrual Period i.e. Ist 10 days of M.C. Q (i.e. within in 10 days of onset of menstruation). This was stated in the belief that there was then least likelihood of conception taking place (but if it did, the embryo would be most sensitive to radiation) it is now believed that fetus is relatively insensitive to radiation in early stages of pregnancy, any adverse effect leads to spontaneous aboion. The fetus is most sensitive to radiation, at 8-15 weeks gestation for increased incidence of Down's Syndrome and slight reduction in IQ.


Question: Soap bubble appearence on abdominal radiograph is associated with

Soap-bubble' effect of gas mixed with 'meconium', commonly seen with 'meconium ileus'.


Question: Most commonly used Piezoelectric crystal is

Most Commonly used Piezoelectric Crystal in Ultrasound probe is Lead Zirconate Titanate. Quaz is a natural piezoelectric crystal. Piezoelectric Crystals conve electrical energy into sound waves and sound waves back into electric current. Ultrasound transducers act as both transmitter and receiver. Other impoant points for USG: - USG uses Harmonic imaging (better image quality) - USG uses Pulse echo principle - Frequency of USG waves in USG is 2-20 MHz NOTE Lead Lead is m/c agent used for radiation shielding. Lead aprons safeguard workers from effects of scattered radiations TLD badgesthat are worn under the aprons, to monitor radiation dose are made up of Lithium flouride/dysprosium. Walls and glass of CT scan room are made up of lead.


Question: Impared Renal Function is assessed by


Question: Tumor associated with extracranial spread


Question: The best view to visualize zygomatic arches is


Question: Point A in radiotherapy for Ca cervix corresponds to

Manchester-Point A SystemThe Manchester System was designed for use with LDR radium brachytherapy. It is the most commonly used technique. Point A - Representing the paracervical triangle (where the uterine aery crosses the ureter). This is the commonly repoed dose point. The position has varied several times, but the most modern definition is 2 cm along the most inferior source within the tandem (alternatively 2 cm along the tandem from the external cervical os), and 2 cm lateral to the tandem. Point A is recorded for all brachytherapy treatments, even those that use image-guided techniques.Point B - Representing the pelvic sidewall/obturator nodes, Point B is located 5 cm lateral to the midline at the same level as point A. It also gives a guide as to the lateral spread of the radiation dose.ICRU Repo 38The ICRU released repo 38 regarding dosimetry of cervical cancer brachytherapy. It discouraged the use of Point A and Point B.It also recommended that bladder and rectal point doses be included.Bladder Point - After inseion of a Foley catheter, the balloon is inflated with 7 ml of contrast. The catheter is then pulled until the balloon rests against the urethra. The bladder point is the most posterior pa of an anteroposterior line drawn through the center of the balloon.Rectal Point - The rectal point is located 5 mm posterior to the posterior vaginal wall, along with a line perpendicular to the midpoint of the activity of the ovoids.The ICRU also recommended repoing of multiple other dose points, including pelvic wall points. These are not commonly repoed. The repoing of the dose delivered to the treatment volume was based on the length, width, and depth of the pear-shaped volume generated by the treatment.(Diagnosis and Management of Cancer by Asok Metha,page73)


Question: Cobra head deformity is characterstic of


Question: Unilateral elevation of diaphragm is commonly due to

Causes of unilateral elevation of the dome of diaphragm: 1. Idiopathic 2. Eventration 3. Muscular disease 4. Radiation therapy 5. Neurologic disease (Stroke, polio) 6. Trauma, Erb's palsy


Question: Most useful investigation of choice for liver abscess is

Ans. (b) UltrasoundRef: Bailey & Love 25th 169* On ultrasound, an abscess cavity in the liver is seen as a hypoechoic or anechoic lesion with ill-defined borders; internal echoes suggest necrotic material or debris. The investigation is very accurate and is used for aspiration, both diagnostic and therapeutic.* Where there is doubt about the diagnosis, a computerized tomography (CT) scan may be helpful.Also KnowDiagnostic pointers for infection with Entamoeba histolytica* Bloody mucoid diarrhoea in a patient from an endemic area or following a recent visit to such a place* Upper abdominal pain, fever, cough, malaise* In chronic cases, a mass in the right iliac fossa = amoeboma* Sigmoidoscopy shows typical ulcers--biopsy and scrapings may be diagnostic* Serological tests are highly sensitive and specific outside endemic areas* Ultrasound and CT scans are the imaging methods of choice.


Question: Most impoant investigation for posterior urethralvalve is


Question: Slip ring technology is used in

A Slip ring is an electromechanical device that allows the transmission of power and electrical signals from a stationary to a rotating structure. A slip ring can be used in any electromechanical system that requires rotation while transmitting power.


Question: Most common cause of widening of C loop of duedenum


Question: Hamman's sign is positive in emphysema.


Question: Gestation sac is picked up by USG earliest at


Question: Radioisotope used for thyroid treatment of metastasis / ablation

Ans. (b) 1-131Ref: Sutton 7th/1504* Iodine-131 has a radioactive decay half-life of about eight days.* Iodine-131 exhibits a beta mode of decay, and leads to death in cells that it penetrates up to several millimeters and hence is useful for thyroid ablation.* 1-123 has a half-life of 13.22 hours and is a radioactive isotope of iodine used in nuclear medicine imaging, including single photon emission computed tomography.


Question: The given lesion is best associated with

Pale infarctions in the CNS best characterize the lesions associated with an atherosclerotic (ischemic) stroke. The four major causes of a cerebrovascular accident, or stroke, in order of frequency, are ischemia (60% to 90% of cases), intracerebral hemorrhage (e.g., hypeensive bleed), subarachnoid hemorrhage (e.g., ruptured berry aneurysm, aeriovenous malformation), and embolic infarction (e.g., hemorrhagic infarction). As a general rule, ischemic strokes are pale (80% of cases) and the other three are hemorrhagic. The majority of ischemic strokes are due to atherosclerosis. Atherosclerotic infarctions are most commonly secondary to a thrombus overlying an atheromatous plaque at the origin of the internal carotid aery. Consequences of atherosclerosis involving the cerebral vessels include cerebral infarction, cerebral atrophy, ischemic encephalopathy (laminar necrosis, watershed infarcts), transient ischemic attacks, and thromboembolism of a poion of atherosclerotic plaque to a distant location. They are usually pale infarcts because the atherosclerotic plaque occludes most of the lumen and reperfusion of the infarcted area usually does not occur. Grossly, there is softening of the brain after 6 hours, with a visible loss of normal demarcation between the gray and white matter. Microscopically, "red neurons" (i.e., apoptosis of individual neurons), nuclear pyknosis, and degeneration of myelin are present. After 2 to 10 days, the brain tissue is gelatinous. Neutrophils transiently invade the necrotic area but are soon replaced by microglial cells, many of which have engulfed lipid and appear as gitter cells. From 10 days to 3 weeks, liquefactive necrosis produces cystic areas in the brain. The subjacent brain parenchyma contains reactive astrocytes with eosinophilic cytoplasm. Cerebral infarcts present with a gradual onset of symptoms (i.e., transient ischemic attacks; TIAs), followed by localizing neurologic signs of contra lateral hemiplegia, aphasia, and visual defects (amaurosis fugax), depending on the site of infarction and whether the dominant hemisphere is involved. The majority of patients recover and regain paial restoration of their initial deficits. TIAs occur in patients with fixed atherosclerotic disease and are often caused by dislodgment of platelet and/or cholesterol emboli into the peripheral vessels. They generally last a few seconds to a few minutes and, by definition, recovery is within 24 hours. Unilateral symptoms suggest carotid ischemia, whereas bilateral symptoms suggest veebrobasilar ischemia, especially if accompanied by veigo, dysahria, or dysphagia. Ticlopidine, which inhibits the synthesis of adenosine diphosphate, or aspirin, which decreases the synthesis of thromboxane A2, are commonly used to prevent TIAs.


Question: Egg shell calcification seen in silicosis is due to

(a) Hilar lymphnode enlargement > Enlargement of the hilum is common with chronic and accelerated silicosis. In about 5-10% of cases, the nodes will calcify circumferentially, producingso-called "Eggshell" calcification.> This finding is not pathognomonic (diagnostic) of silicosis. In some cases, the pulmonary nodules may also become calcified.


Question: 'Stipple sign’ in transitional cell carcinoma of the renal collecting system is best demonstrated by

An intravenous pyelogram, also called an intravenous urogram, is a radiological procedure used to visualize abnormalities of the urinary system, including the kidneys, ureters, and bladder.


Question: Best view to seen pneumoperitoneum is

Best view to seen pneumoperitoneum - Chest x-ray in erect position.
If unable to stand - Left lateral decubitus View.


Question: In Renal cell carcinoma investigation of choice to evaluate inferior venacava & renal vein for thrombus


Question: Best investigation for Traumatic paraplegia

B i.e. MRI MRIQ is the investigation of choice for imaging traumatic spine (ex paraplegia). CT is second best investigation.


Question: Not a Radiological feature of ileal atresia

Multiple bubble sign in seen in ileal atresia.


Question: The radiographic appearance of Botryoid odontogenic cyst is

An unusual form of cyst called botryoid odontogenic cyst, manifests radiographically with a multilocular pattern, is simply a polycystic variant of the lateral periodontal cyst developing through cystic transformation of multiple islands of dental lamina rests. The  botryoid odontogenic cyst appears similar, except that its polycystic nature is often evident through its multi-locular pattern on the radiograph.


Question: Calcified lesions are better seen on

CT is better in detecting calcification (eg. pericardial calcification, coronary calcification) bone injury, lung and chest imaging.


Question: The diagnostic procedure not done in case of pheochromocytoma.

Ans. is 'c' i.e. FNAC 1551 "Percutaneous fine-needle aspiration of chromaffin tumors is contraindicated; indeed, pheochromocytoma should be considered before adrenal lesions are aspirated." -Harrison"Catastrophic hypertensive crisis and fatal cardiac arrhythmias can occur spontaneously or may be triggered by intravenous contrast dye or glucagon injection, needle biopsy of the mass, anesthesia, and surgical procedures." -


Question: Sea shore sign on USG is see in

Sea shore sign - Normal lung.
Loss of this pattern (stratosphere sign) - Pneumothorax.


Question: Radiation mediates its effect by


Question: Most common type of Choledochal cyst


Question: Cause of Unilateral Hypertranslucent hemithorax

Poland's (U/L congenital absence of pectoral muscles) - thus hypertransluscency.


Question: Hair on end appearance is most common is

All of the above causes Hair on end appearance.
Thalassemia major > Sickle cell disease.
No Thalassemia major in Options.


Question: Principle used in radiotherapy is


Question: Ioc in Choledocholithiasis

IoC for Cholelithiasis - USG
IoC for Choledocholithiasis - MRCP.


Question: Central dot sign on CT scan is seen in

Caroli disease is a congenital disorder comprising of multifocal cystic dilatation of segmental intrahepatic bile ductsalso classified as a type V choledochal cyst, according to the Todani classificationPathologically, belongs to the spectrum of fibropolycystic liver disease which results from in utero malformation of the ductal plateTwo types - simple and peripoal fibrosisImaging features:CT/US/ MR:central dot sign = poal vein radicles completely surrounded by dilated bile ductsCholangiography (diagnostic):segmental saccular/fusiform/beaded dilatation of intrahepatic bile ducts extending to the periphery of liver up to 5 cm in diameterbridge formation across dilated luminaintraluminal bulbar protrusionsfrequent ectasia of extrahepatic ducts + CBDComplications:Intraductal stonesCholangitis and AbscessLiver cirrhosisCholangiocarcinomaTodani classification:(Ref: Grainger and Allison&;s diagnostic radiology 6th edition, page 797)


Question: Stereotactic radiotherapy is used in

Carcinoma base of tongue with positive lymph nodes


Question: Multiple radio opacities are seen in


Question: The best method of investigation is case of acute cholecystitis is


Question: Best view to detect minimal Right sided pleural effusion

As little as 10 - 25 ml of fluied can be demonstrated.


Question: Tram track calcification is seen in


Question: Vesicouretric reflux is demonstrated by

VUR - Tc 99 - DMSA
GFR estimation Tc 99 - DTPA


Question: Hockey stick appearance on echo is a feature of

Echocardiographic features of mitral stenosis:-Thickened and calcified mitral leaflets and subvalvular apparatus -Decreased E-F slope (M-mode)-Hockey stick appearance of the anterior mitral leaflet in diastole(long axis view)-Immobility of the posterior mitral leaflet (a similar appearance can be seen in hypereosinophilia or ergot use)-Fish mouth orifice in the sho axis view-Increased LA size, with the potential for thrombus formationDynamic CT: the Restricted opening of the thickened valve from commissural fusion (especially with rheumatic valve disease), valve calcification, or both results in a "fish-mouth" appearance on sho-axis images. Bowing of a thickened and fibrotic anterior leaflet during diastole may result in a "hockey-stick" appearance which is best seen on two- or four-chamber images(Ref: The echo manual by Jae K Oh; J B Seward; A Jamil Tajik, page no 202)


Question: Most common cause of Vertebra plana

Vertebra plana:

Uniform collapse of a vertebral body into a thin, flat disc.
M/c cause - Eosinophilic granuloma.


Question: Acro Osteolysis is seen in

Acroosteolysis

Sclerodeima
Hyperparathyoidism
Rheumatomoid arthritis
Raynaud's
Psoriatric arthropathy.


Question: Investigation of choice for evaluation of upper abdominal trauma

Initial investigation in abdominal trauma is FAST (USG) IOC in Abdominal Trauma - CECT


Question: Best Investigation for diagnosing Minimal Right Pleural Effusion is

*IOC for minimal Pleural Effusion is USG *Best X ray View for minimal Pleural Effusion is Ipsilateral Lateral Decubitus View.


Question: SI unit of Radioactivity is


Question: MRI magnet is a

MRI uses a Superconducting magnet which is kept cool using Helium. A superconducting MRI magnet comprises a steel cryostat with the superconducting coils immersed in liquid helium at 4.2 Kelvin (-269degC or -452degF).


Question: Pesudo fracture of looser's zone is seen in


Question: Absent lateral third of clavicle is seen in

CLEIDOCRANIAL DYSPLASIA/DYSOSTOSIS (CCD)Autosomal recessive disease with faulty intramembranous bone ossificationLarge head with small face, abnormal dentition and drooping hypermobile shouldersRadiological features:Skulla. Platybasia b. Large foramen magnum c. Wormian bonesd. Persistent metopic suture e. 'Hot cross bun' skull f. BrachycephalyThoraxa. Agenesis or hypoplasia of clavicles b. Small winged scapulaePelvisa. Underdeveloped pelvis b. Coxa valgus earlySpinea. Biconvex veebrae b. HemiveebraeExtremitiesElongated 2nd metacarpalD/d: pyknodysostosis (confused with CCD because of similar clavicular and skull changes, and pyknodysostosis is also confused with osteopetrosis because generalized increase in bone density, however these patients are not sho which differentiate it from CCD)


Question: Capsule endoscopy is used for

Video capsule endoscopy provides visualization of the GI tract by transmitting images wirelessly from a disposable capsule to a data recorder worn by the patient.WCE (wireless capsule endoscopy) has been approved for a number of indications in patients as young as 2 years. Most common indications :obscure GI bleeding (OGIB), both ove and occult, including iron deficiency anaemia (2) suspected Crohn's Disease (3) surveillance of patients with polyposis syndromes; (4) suspected small-intestine tumours; (5) suspected or refractory malabsorptive syndromes (eg, celiac disease).Relative contraindications:(1) with known or suspected GI obstruction, strictures, or fistulas based on the clinical picture or pre-procedure testing, (2) with cardiac pacemakers or other implanted electromedical devices, (3) with swallowing disorders, (4) who are pregnant.However Multiphasic contrast-enhanced CT enterography with wireless capsule endoscopy found significantly greater sensitivity with CT enterography than capsule endoscopy (88 vs 38%) in identifying a source of occult gastrointestinal bleeding.In clinical practice, CT enterography and capsule endoscopy are complementary, paicularly in the investigation of benign causes of blood loss(Ref: Grainger and Allison&;s diagnostic radiology 6th edition, page no 674 and Aicle on Wireless capsule endoscopyVolume 78, No. 6: 2013 GASTROINTESTINAL ENDOSCOPY)


Question: IOC for determing the etiology of sub arachnoid hemorrhage

Four vessels (Both carotid and both vertebral) digital subtraction angiography is the IOC for determing the etiology of SAH.


Question: Xray view for superior orbital fissure is

In plain AP view and Towne&;s view we can see the Temporal bone and sinus, zygoma, zygomatic arch and mandibleSuperior orbital fissure can be seen by Caldwell view and water&;s view.X-ray views of OrbitPA view, Caldwell Luc view Superior orbital fissureAp view, Townes viewInferior orbital fissureRhese viewOptic foramenPNS/ Water&;s viewFloor of orbit


Question: 1 Gray is equal to

Ans: c (100 Rad) Ref: Practical Radiotherapy- Physics and equipment 2nd ed/p.25, 2521 Gray = 100 RadGray is defined as: ' The absorbed dose (D) is the quotient of de by dm, where de is the mean energy imparted by the ionising radiation to matter of mass dm. D = de dmThe S.I unit of absorbed dose is gray. 1 Gray = 1 joule per kg = 100 RadIntensity is defined as the X - ray energy passing through unit area per unit time and is measured in roentgens.Rem is the Rontgen equivalent man, where absorbed dose of rads is multiplied by the quality factor of the type of radiation. The biological effect of radiation is expressed in Rem.


Question: Following RAIU studies demonstrate


Question: The sialographic appearance of a normal salivary gland is


Question: Mexican hat sign is seen in

Pedunculated colonic polyps form the "Mexican hat sign." The Mexican hat sign is formed by the appearance of 2 concentric rings; the outer ring represents the "en face" visualization of barium coating the surface of the head of a pedunculated polyp, while the inner ring represents a meniscus of barium surrounding the stalk of the polyp visualized through the head


Question: Stereotactie surgery is used for treatment of


Question: The "Great Hilar Dance" sign of flouroscopy is seen in

Vigorous arterial pulsations due to increased blood flow, seen flouroscopically in patients with ASD.


Question: Investigation of choice for retinoblastoma is

Retinoblastoma is malignant congenital intraocular tumour arising from primitive photoreceptor cells of the retina (included in primitive neuroectodermal tumour group)Two types -Heritable and non-heritableTrilateral retinoblastoma (rare variant)= bilateral retinoblastomas + neuroectodermal pineal tumor (pineoblastoma)Quadrilateral retinoblastoma= trilateral retinoblastoma + 4th focus in suprasellar cisternMRI is the modality of choice for pre-treatment staging on retinoblastomaPrognosis: Spontaneous regression in 1%Calcification is a ourable prognostic signContrast enhancement is a poor prognostic sign(Ref: Radiology Review ManualBy Wolfgang Dahne 6thEtd, 351)


Question: Not a characteristic feature of meningioma


Question: Trapped air sign in upper abdomen on plain xray is seen in

Shopfner described this sign in patients with peri Gastric adhesions.It consists of trapped air pockets in pas of the Gastric antrum, elevated and fixed by perigastric adhesions to adjacent organs like liver and pancreasValuable in excluding Gastric carcinomasMost commonly seen in benign conditions


Question: An oval radiolucent area between the apices of maxillary incisors is


Question: Investigation of choice for acute head injury

Ans. A. NCCT brain* CT is the investigation of choice to identify acute intracranial bleed and hence is the preliminary investigation in acute head injury.* Investigation of choice for brain hemorrhage is NCCT brain* Investigation of choice for calcification is NCCT Brain* Other than above three pathology investigation of choice for neurological lesion is MRI.Investigation of choice in Neurology* Investigation of choice for optic neuritis is MRI* Investigation of choice for vestibular schwannoma is MRI* Investigation of choice for Multiple sclerosis is MRI* Investigation of choice for hippocampal volumetry is MRI* Investigation of choice for viral encephalitis is MRI* Investigation of choice for Pituitary adenoma is MRI* Investigation of choice for Spinal cord tumor is MRI* Investigation of choice for Neurofibroma is MRI* Investigation of choice for hemorrhagic stroke is NCCT brain* Investigation of choice for ischemic stroke is diffusion weighted MRI* Investigation of choice for Stroke is NCCT brain (since initially, we have to rule out hemorrhagic stroke).


Question: Earliest radiological change to appear in case of acute osteomyelitis is

Ans. Loss of plane between soft tissue and muscle


Question: Pseudokidney sign' on USG is seen in


Question: Earliest radiological feature of ulcerative colitis


Question: Best way to know the position and integrity of ICD (implantable Cardioverter defibrillator) is

Best way to know the position and integrity of ICD is to do a plain radiograph.


Question: Not a radiological finding of papillary necrosis on excretory urogram is

Ans is 'c'. i.e. Increased dense nephrogramThe diagnosis of papillary necrosis depends on the demonstration of calyceal and papillary abnormalities without associated parenchymal loss. The calyceal and papillary abnormalities fall into two groups:Those that are characteristic of papillary necrosisTracks and horns of contrast medium arising from the calyceal Fornices (representing necrosis around the papillary margin.)Egg in a cup appearance (due to central necrosis producing central pool of contrast within the papillae)Ring shadow (Papillary sloughing produces a central lucent filling defect with a surrounding ring of contrast medium)Those that are non-specificThe end result of papillary sloughing is clubbed, blunt or truncated calyces.Renal papillary necrosis refers to coagulative necrosis of the renal medullary pyramids and papillae brought on by several associated conditions and toxins that exhibit synergism toward the development of ischemia. Renal papillary necrosis may be localized or diffuse and unilateral or bilateral.Renal papillary necrosis can lead to secondary infection of desquamated necrotic foci, deposition of calculi, and/or separation and eventual sloughing of papillae, with impending acute urinary tract obstruction. Sinus like tracts and cavitation's may be seen surrounding the sloughed papilla. Multiple sloughed papillae can obstruct their respective calyces or can congregate and embolize to more distal sites (eg, ureteropelvic junction, ureter, ureterovesical junction)Renal papillary necrosis is potentially disastrous and, in the presence of bilateral involvement or an obstructed solitary kidney, may lead to renal failure.Certain conditions have a known association with renal papillary necrosis, and the underlying mechanism of these conditions is ischemia, which ultimately leads to renal papillary necrosis.Analgesic abuseObstruction of the urinary tract with infectionSickle cell diseaseDiabetes mellitus


Question: Most common supratentorial tumor in children

M/c supratentorial tumor in children is craniopharyngioma. It is a suprasellar tumor.arising from embryonic rathkes pouch.


Question: Calcification of meniscal cailage is a feature of

Notable sites of chondrocalcinosis in pseudogout include: * knee: medial meniscus and patellofemoral joint * wrist: triangular fibrocailage complex and lunotriquetral ligaments * pubic symphysis * spine - interveebral discs


Question: Globular heart with plethoric lung fields is seen in

Globular heart with plethoric lung fields - TGA
Globular heart with Oligemic lung fields - Tricuspid atresia, Ebstein's anomaly


Question: Iodine paicle ratio for Ionic dimer is

Iodine paicles ratio: I: P Ionic monomer 3: 2 High osmolar Low Osmolar Ionic dimer 6: 2 Nonionic monomer 3: 1 Low osmolar Non-ionic dimer 6: 1 Iso-osmolar to plasma(290-300mosm)


Question: Clover Leaf Skull is seen in

Clover Leaf Skull is seen in Thanatophoric dysplasia type II, premature closure of saggital, coronal and lambdoid sutures causing severe craniosynotosis giving rise to trilobate shape of skull. Luckenschadel skull or Lacunar Skull is seen in Chiari II malformations. Geographical skull is seen in Eosinophilic Granuloma. Rain Drop Skull is seen in Multiple Myeloma.


Question: Direct action of radiation is the dominant process for

Ionizing radiation acts by two methods: Direct and IndirectDirect action is radiation directly causing DNA damage; example: neutrons and alpha paiclesIndirect action is radiation causing free radical production which acts on DNA; example: photons and gamma raysReference: Khan Physics of Radiation therapy; 5th edition


Question: Diffuse axonal injury is best detected in

The diffuse axonal injury is the result of shearing forces, typically from rotational acceleration Due to the slightly different specific gravities (relative mass per unit volume) of white and grey matter, shearing due to change in velocity has a predilection for axons at the grey-white matter junction, as the name implies. In the majority of cases, these forces result in damage to the cells in a way that causes cell oedema. Imaging featuresThe diffuse axonal injury is characterized by multiple focal lesions with a characteristic distribution: typically located at the grey-white matter junction, in the corpus callosum and in more severe cases in the brainstem CTNon-contrast CT of the brain is routine in patients presenting with head injuries. But it is not terribly sensitive to subtle diffuse axonal injury. The appearance depends on whether or not the lesions are ovely hemorrhagic. Hemorrhagic lesions will be hyperdense and range in size from a few millimeters to a few centimeters in diameter. Non-hemorrhagic lesions are hypodense. They typically become more evident over the first few days as edema develops around them. They may be associated with significant and dispropoionate cerebral swelling. MRIMRI is the modality of choice for assessing suspected diffuse axonal injury even in patients with entirely normal CT of the brain.SWI or GRE sequences, exquisitely sensitive to paramagnetic blood products may demonstrate small regions of susceptibility aifact at the grey-white matter junction, in the corpus callosum or the brain stem. Some lesions may be entirely non-hemorrhagic (even using high field strength SWI sequences). These will, however, be visible as regions of high FLAIR signal. MR spectroscopyMRS can be of benefit in identifying patients with grade I injury which may be inapparent on other sequences. Features typically demonstrate elevation of choline peak and reduction of NAASTAGING, GRADING, AND CLASSIFICATION: The Adams and Gennarelli classification defines mild, moderate, and severe grades of TBI.In mild TBI, lesions are seen in the frontotemporalgraywhite matter interfaces. The injury is designated as moderate when the lobar white matter and corpus callosum are affected. In severe TBI, lesions are present in the dorsolateral midbrain and upper pons. More than half of all TBI cases with DAI are designated as moderate to severe.(Ref: Osborn's Brain: Imaging, Pathology, and Anatomy, page 37)


Question: A patient is suspected to have vestibular schwanomma. The investigation of choice for its diagnosis is


Question: Loss of Lamina dura is observed in


Question: Investigation of choice for pulmonary embolism


Question: Seminoma is best treated by

(B) Radiation and surgery # Seminomas are radiosensitive and excellent results have been obtained by irradiating stage 1 & stage 2 tumours.> If there is no metastasis ,95%of patients will be alive 5 years after orchidectomy and radiotherapy or chemotherapy. If there is metastasis survival drops to 75%.


Question: Brain infarct is detected at the earliest by

Diffusion weighted imaging (DWI) is the most sensitive sequence for stroke imaging, becomes positive within minutes in >95% cases"Diffusion-negative" acute strokes may be Small (lacunar) infarcts, Brainstem lesions, Rapid clot lysis/recanalization, and Transient/fluctuating hypoperfusionDiffusion tensor imaging (DTI) is even more sensitive than DWI, especially for pontine and medullary lesionsOn CT Early signs of ischemiaHypo attenuating brain tissueObscuration of the lentiform nucleusInsular Ribbon signDense MCA signHemorrhagic infarcts(Osborn's Brain: Imaging, Pathology, and Anatomy, page 189,190,191)


Question: String of kantor is seen in

The gastrointestinal string sign (string sign of Kantour) refers to the string-like appearance of a contrast-filled bowel loop caused by severe narrowing of a bowel loop.Originally used to describe the reversible narrowing caused by spasms in Crohn disease, it is now used for any severe narrowing of the bowel lumen, including that seen in hyperophic pyloric stenosis, gastrointestinal tuberculosis, carcinoid tumor and colon cancer.(Ref: Grainger and Allison&;s diagnostic radiology 6th edition, 662)


Question: Gyromagnetic propey of Hydrogen nucleus is used in

MRI is based on Gyromagnetic propey of H+ ions, Protons. ULTRASOUND is based on Pulse echo principle and Piezoelectric effect. CT SCAN is based on Linear attenuation of X rays.


Question: Thyroid malignancies appear on USG as

On sonography, thyroid tumors are solid,hypoechoic masses.


Question: Most sensitive structure in cell for radiotherapy is

(C) DNA # Radiotherapy is a physical form of treatment that damages any tissues in its path. Tumor cells seen somewhat more sensitive to the lethal effects of radiation than normal tissues primarily because of differences in ability to repair sublethal DNA & other damage.> In the target tissue,radiation damages DNA (usually single stand breaks) & generates free radicals form cell water that are capable of damaging cell membranes,proteins & organelles.> Since DNA is the most important subcellular target of ionizing radiation,rapidly dividing cells are more radiosensitive than quiescent cells. Radiation- damage is dependent on 02 ; hypoxic cells are more resistant. Cells in cell cycle of late G,& S are more reristant to radiation & cells in the G2 & M phases are most sensitive to Radiation


Question: Best view for interlobar pleural effusion

Major fissure (oblique) is seen only in Lateral x-ray, - so, it is best to view for interlobar pleural effusion.


Question: MRI finding of face of panda appearance is seen in


Question: Sitting duck heart is radiological finding of

Sitting duck heart - Persistent truncus arteriosus.
Jug handle appearance - Primary pulmonary hypertension.


Question: Maximum radiation exposure occurs in

Ans. d. CT scan Maximum radiation exposure occurs in CT scan among the given options.


Question: Most sensitive sonological indicator for aneuploidy is

Ans. is 'c' i.e. Nuchal translucency Rumack writes - "The most effective sonographic marker of trisomy 21 and other chromosomal defects is increased nuchal translucency (NT) thickness at 11 to 14 weeks gestation."


Question: Duplex ultrasound is a combination of

Duplex Scan Combination of B-mode imaging with Pulsed Doppler USG - gives both anatomical & physiological information of vascular system. Colour Duplex Scan Addition of colour frequency mapping - Colour Duplex imaging.


Question: Cervical burnout is a phenomenon caused by

Decreased X-ray absorption in the cervical region of teeth with proximal caries

Decreased X-ray absorption in the cervical region of normal teeth

Decreased X-ray absorption in the cervical region of teeth with root caries

Decreased X-ray absorption in the cervical region of hypoplastic teeth


Question: Unit of measurement to compare radiation damage


Question: Double track sign is seen in

Double/triple track sign is seen in congenital hypertrophic pyloric stenosis


Question: 'Flower vase' appearance on intravenous urogram is seen in

Duplex system with upper moeity ureterocele


Question: A deterministic effect

Deterministic effect: severity increases with dose; practical threshold; the probability of occurrence increases with dose; e.g., cataract.Stochastic effect: severity independent of dose; probability of occurrence increases with dose; no threshold; e.g., cancerReference: Eric J Hall Textbook of Radiobiology for Radiologist; 5th edition

Has a threshold in dose but the severity of the effect is otherwise dose-independent

Has a threshold in dose and the severity of the effect increases with dose

Has no threshold in dose and the severity of the effect is a constant function of dose

Has no threshold in dose and the severity of the effect increases with dose


Question: An expiratory film is particularly useful to detect

Best view for Pneumothorax - PA view in full expiration.


Question: Three dimensional localization of a tooth in maxillary sinus is best achieved with the following

Lateral cephalogram + maxillary occlusal


Question: Molar pregnancy can be best diagnosed by

USG is the investigation of choice for molar pregnancies.


Question: On USG finding of cystic hygroma in fetus is suggestive of


Question: Flat waist sign is seen in

FLAT WAIST SIGN Flattening of the contours of the aoic knob and adjacent main pulmonary aery. Seen in left lower lobe collapse Caused by leftward displacement and rotation of the hea


Question: Characteristic radiological finding in sarcoidosis


Question: The most common lesion to simulate a cementoblastoma is

The most common lesion to simulate a cementoblastoma is a solitary lesion of periapical cemento-osseous dysplasia. The differential interpretation may be difficult in some cases, and the presence or absence of symptoms or observation of the lesion over a period of time may be required. Generally, the radiolucent band around the cementoblastoma is usually better defined and
uniform than with cemento-osseous dysplasia. Also, owing to the pattern of concentric growth of the cementoblastomas, the overall shape is more uniform and spherical than the more irregular undulating outline of the cementoosseous dysplasia. Other lesions that may be included in the differential interpretation may include periapical sclerosing osteitis, dense bone island, and hypercementosis.


Question: Not a feature of Achondroplasia

Achondroplasia :- - an autosomal dominant condition with altered FGFR3 Gene - Most common skeletal dysplasia - It has Rhizomelic Dwarfism(Shoened Proximal Bones) - M/C/C of dispropoionate dwarfism Features includes :- - champagne glass pelvis - tombstone iliac bone - bullet shaped veebra Bowed and sho bones of the legs with square lilac blades and champangne glass pelvis. Achondroplasia.


Question: Radiological sign of ischemic colitis is


Question: Double bubble sign is seen in A/E


Question: Maximum radio opaque shadow in ovary is seen in

A i.e. Teratoma In teratoma, there may be presence of tooth & other calcified bodies giving rise to radio-opaque shadows.


Question: The following will be most helpful radiological investigation in a patient suspected of left pleural effusion


Question: Obscuration of left hea border is suggestive of

Silhouette sign : Obscuration of a mediastinal border occurs by a pathology which is in close anatomical contact with it Obscuration of Rt Hea Border Rt Middle Lobe Pathology Obscuration of Left Hea Border Lingular Pathology Obscuration Of Aoic Knuckle Left Apicoposterior pathology Obscuration of Hemidiaphgrams Lower lobe pathologies


Question: Maximum scattering in X Ray plate occurs in

C i.e. H+ Major difference between x-rays & light are wave length (A) & energyQ Electromagnetic radiation or photon waves are non paiculate (0-mass), non charged (0-charge) waves, that do not require a medium to travel (i.e. can travel in vaccum) and transfer energy from one location to another at the speed of light (c= 3x108 m/s). The major difference between various forms of photons/electromagnetic radiation lies in their wave length (X) and frequency (n), which accounts for their differences in energy carried. E n/A. So Xrays with shoer wave length in comparison to visible light carries 5000 times higher energies. Because for EM waves energy is propoional to frequency (n) and inversly propoional to wave length N. - EM radiation spectrum consists of photons with wave length, frequency and energy ranges over 10 orders of magnitude (the range is really infinite). From low energy to high energy these are Radar waves, Microwaves, Infra-red, Light (visible photons), Ultraviolet, X rays and Gamma rays. (Mn- "Reliance MILL Xtra Grand"). - When a photon beam falls, it can exit (transmitted electrons) or interact with matter (attenuation). With increasing amount of photon energy 5 possible interactions are possible, which are coherent scattering (very low energy electrons;1.022 to > 10 MeV), and photodisintegration (very high energy; > 8-10 MeV) - Maximum compton scattering occurs with hydrogenQ b/o highest electron density. In photoelectric effect, the most tightly bound-inner most electron completely absorbs all energy of falling low energy photonQ, so much so that the photon is completely absorbed and no longer exists and inner orbital electron (now called photoelectron) is ejected. The interaction can occur with other orbital electrons but the most probable interaction is with inner most shell electron. The vacency created in inner shell is filled by an electron from outer orbit with simultraneous emission of X-ray or Auger electron. In Compton Scattering incident higher energy photon transfers only a pa of its energy to a loosely bound outer shell electronQ. and is deflected or scattered off in a new direction with lower energy. The outer shell electron (now called compton/recoil electron) is ejected with no production of X-ray or Auger electron. Charged heavy paicles (such as protons and a-paicles) have a finite range and experience a rapid increase in energy loss near the end of their track (range/path), dumping most of their remaining energies quickly and producing an ionization curve with a peak near end (K/ a Bragg peak). - When a light mass-charged paicle (such as electron or 8-paicle) with high energy passes close to the nucleus's positive electrical field, it is deflected & decelerated by electro static attractions and loses energy in form of X-ray photons called bremsstrahlung or braking radiation. So Bragg peak is produced by charged heavy paicles mainly, whereas Bremsstrahlung radiation is produced by charged light paiclesQ. - Collisional energy losses (& heat production) dominate at lower energyies, whereas radiative losses dominate at higher energies (Vt more efficient X-ray production)Q. Because of dependency on atomic number (Z2) and 1/velocity2; collisional energy losses increases as atomic number increases and paicle velocity decreases. So electrons are stopped sooner in low Z than high Z materialsQ.


Question: Best radiographic view for fracture C1 and C2 veebra is

Odontoid view is best to view fractures of C1 & C2.


Question: Principles of Linear accelerators is used in


Question: Phosphorus32 emits


Question: Anencephaly can be diagnosed by USG at

A i.e. 10-12 weeks of gestation Earliest detectable congenital anomaly on USG is Anencephaly.Q Anencephaly can be diagnosed - Earliest at 10 weeksQ Best at 12 weeksQ (100% accuracy)


Question: Not a radiosensitizing agent


Question: International Day of Radiology is celebrated on

8th November of each year is celebrated as International Day of Radiology(IDOR) X Rays were discovered by W.C.Roentgen on 8th November 1895, so 8th November is celebrated as International Day of Radiology every year. Theme for IDOR 2019: spos imaging


Question: Split Pleura sign is seen in

The split pleura sign is seen with pleural empyemas and is considered the most reliable CT sign helping to distinguish an empyema from a peripheral pulmonary abscess. The sign results from fibrin coating both the parietal and visceral surfaces of the pleura with resulting ingrowth of blood vessels with accompanying enhancement. Both layers of the pleura can then be visualized as linear regions of enhancement that come together at the margins of the collection.Ref: Kazerooni Ella A and Barry H Gross. The Core Curriculum: Cardiopulmonary Imaging. 1st ed. Lippincott Williams & Wilkins, 2003. ISBN: 0781736552


Question: Most probable diagnosis on this barium film is

Features on barium small bowel follow-through in Crohn&;s disease include:mucosal ulcersaphthous ulcers initiallydeep ulcers (>3 mm depth)longitudinal fissurestransverse stripeswhen severe leads to cobblestone appearancemay lead to sinus tracts and fistulaewidely separated loops of bowel due to fibrofatty proliferation (creeping fat) thickened folds due to oedemapseudodiveicula formation: due to contraction at the site of ulcer with ballooning of the opposite sitestring sign: tubular narrowing due to spasm or stricture depending on the chronicitypaial obstructionon control films presence of gallstones, renal oxalate stones, and sacroiliac joint or lumbosacral spine changes should be soughtSource:


Question: Most common cause of renovascular hypertension in children and young adults


Question: Expansible pulsating secondary metastasis is a feature of


Question: Spinnaker sign is a feature of

Thymic sail sign is the normal appearance of thymic shadow abutting the Hea shadow seen on Chest X ray of a normal Infant Spinnaker sail sign is the lifting of the Thymic shadow with the lucency of air between Thymus and Hea in cases Of Pneumomediastinum thymus sail sign- normal spinnaker sign


Question: Value of total filtration for 70 kVp is

Total filtration is the sum of the inherent and added filtration. Governmental regulations require the total filtration in the path of a dental x-ray beam to be equal to the equivalent of 1.5 mm of aluminum for a machine operating at up to 70 kVp and 2.5 mm of aluminum for machines operating at higher voltages.
Oral Radiology, Principles and Interpretation / Stuart C. White, Michael J. Pharoah - 7th ed - pg - 10,11


Question: Perihilar fluffy opacities on Xrays are seen in

Pulmonary venous hypeension:It is caused by increased resistance to blood flow in the pulmonary veins, due to obstruction or reduced compliance within the left atrium, at the mitral valve, or within the left ventricle.It is divided into 3 grades of severity:Grade I PVH:a. Reversal of normal gravity dependent gradient of pulmonary blood flow with the diameter of upper lobar vessels greater than that of lower lobe vesselsb. Enlargement of the right superior pulmonary vein with loss of hilar angle lateral concavity of hilumc. Loss of visibility of mid and distal poions of the right descending pulmonary trunkGrade ii PVH:d. Interstitial pulmonary edemae. Pleural effusionGrade iii PVH:f. Alveolar pulmonary edema with bilateral fluffy alveolar opacitiesg. Cardiomegaly left atrial enlargement*Flask-shaped / Pear-shaped / Leathe- bottle / Money-bag shaped hea - Pericardial effusion* Boot-shaped hea / Coer-en-sabot - Fallot&;s tetralogy* Box shaped appearance - Tricuspid atresia* Jug Handle appearance - Primary pulmonary aery hypeension* "3" like appearance - Coarctation of Aoa* Egg on side appearance - Transposition of great vessels* Egg in cup appearance - Constrictive pericarditis* Snow-man hea - TAPVC (total anomalous pulmonary venous connection)* Figure of &;8&; - TAPVC (total anomalous pulmonary venous connection)* Cottage Leaf appearance - TAPVC* Pericardial calcification - Constrictive pericarditis* Calcification in hea wall - is seen in - Carcinoid syndrome* Calfication of ascending aoa - Atherosclerosis, Syphilis* Hilar dance on fluoroscopy - Atrial Septal Defect* Xray finding in Ebstein&;s anomaly - Pulmonary oligemia* Posterior displacement of trachea - seen in - aneurysm of the aoa* Obliteration of left border of hea (PA view of the chest) is - suggestive of - Lingular pathology (left lung)* Bat&;s wings appearance - Pulmonary edema* Pruned tree appearance (of pulmonary circulation) - Pulmonary aery hypeensionLungs* Ground glass appearance - Hyaline membrane disease* Solitary pulmonary mass lesion > 4cms - is most commonly due to - Bronchial adenoma* HoneyComb appearance - -Sarcoidosis -Histiocytosis X -Interstitial lung disease -Tuberculosis -Collagen disorders -Pneumoconiosis -Drugs - bleomycin, busulphan, melphalan, cyclophosphamide* Meniscus sign / Crescent sign (mobile mass in pulmonary cavity) is most commonly seen in - Aspergilloma (fungal ball lesion)* Egg-Shell calcification - SilicosisQ , SarcoidosisQ , Coal miner&;s pneumoconiosis, Lymphoma following radiotherapyQ* Pop-corn calcification / Craggy pop-corn calcification - Pulmonary Hamaoma* Pleural calcification - the commonest cause is - Tuberculosis (Asbestosis)* Diaphragmatic Pleura calcification - is due to - Asbestosis* Calcification of a pulmonary metastasis - is most commonly due to - Osteosarcoma* Coin shadow in the lung (single), with calcification in the center - Epidermoid carcinoma* For radiologically evident pleural effusion - the minimal amount of pleural fluid that should be present is - 250 ml* Plethoric lung fields - seen in - L-R shunts ( VSD, PDA, ASD)* Oligemic lung fields - Pulmonary atresia, Stenosis; Ebstein&;s anomaly* Perihilar fluffy opacities - seen in - Pulmonary venous hypeensionRibs* Superior surface notch of ribs - seen in - Hyperparathyroidism, Neurofibromatosis, Connective tissue disorders* Inferior surface notch of ribs - seen in - Coarctation of Aoa, SVC obstruction, Chest wall AV fistula, Aoic Thrombosis,* Unilateral notching of ribs - Coarctation of Left subclan aery, Subclan aery block, Blalock-Taussig OperationOthers* Displacement of tracheal shadow - most common cause is - Thyroid swelling* Water Lily sign - Ruptured hydatid cyst(Ref: David Sutton; Textbook of radiology and imaging, 7th edition, page no.552-3, 866; Grainger&;s diagnostic radiology, 4th ed,. 874)


Question: Not a Radioprotector

BUDR is a Non-hypoxic cell Radiosensitizer.


Question: Technitium 99 is most commonly used in

RADIO NUCLIDE IMAGING 99Tc is the most commonly used radiopharmaceutical, for imaging in nuclear medicine.


Question: Bird of prey sign is seen in

Sigmoid volvulus is a cause of large bowel obstruction and occurs when the sigmoid colon twists on the sigmoid mesocolon. Imaging signs areRadiograph:coffee bean signFrimann Dahl&;s sign - three dense lines converge towards the site of obstructionabsent rectal gas water-soluble contrast enema - the beak sign (or bird beak sign). CTlarge gas-filled loop without haustral markings, forming a closed-loop obstructionwhirl sign: twisting of the mesentery and mesenteric vesselsbeak sign: if rectal contrast has been administered (Ref: Grainger and Allison&;s diagnostic radiology 6th edition, chapter 25)


Question: Investigation of choice for Aoic Dissection is


Question: In a child of one month age with history of nonbilious vomiting and no weight gain with palpable epigastric lump, first investigation to be done is

Ans. b (Ultrasonography) (Ref. Bailey and Love 25th/pg. 79)CONGENITAL HYPERTROPHIC PYLORIC STENOSIS (CHPS/IHPS)# Increased incidence in firstborn male child with M:F ratio 4:1. Incidence of hypertrophic pyloric stenosis is approximately 2-5 per 1,000 births per year.# Most commonly affects boys aged 2-8 weeks# Characterised by projectile vomiting after feeds# Gastric peristalsis can be seen and a lump felt# Inherited as dominant polygenic trait.# Ultrasound (investigation of choice)The diagnosis can be confirmed by an ultrasound scan, which shows the thickened pyloric muscle.# Pyloric muscle wall thickness 2.5-3 mm# Pyloric volume > 1.4 cm3# Pyloric length > 1.2 cm# Pyloric transverse diameter 13-16 mm with pyloric channel closed.- Target Sign: Hypoechoic ring and hypertrophied pyloric muscle around echogenic mucosa centrally (transverse scan).- Cervix sign and antral-nipple sign: indentation of muscle mass on fluid-filled antrum (longitudinal scan).Normal values:# Pyloric canal length: < 15 mm# Muscle wall thickness: < 3 mm# Pyloric width: < 7 mm# Contrast radiology (*Barium study) is now not necessary.# Upper Gl Imaging (barium study) -features- Elongation and narrowing of pyloric canal (2-4 cm length) with string sign, double/triple track sign, diamond sign/twining recess, pyloric teat/teat sign, beak sign/antral beaking, umbrella/kirklin/mushroom sign and caterpillar sign may be seen.# Treatment:- Ramsted's Pyloromyotomy (splits the hypertrophied muscle leaving the mucosa intact).Additional Educational points:ULTRASOUND is investigation of choice for diagnosing:# Initial test of choice (Screening) for blunt trauma abdomen (Focused Assessment by Sonography for Trauma), focal liver lesions, obstructive jaundice or acute abdomen.# Hydrocephalus in infants, Neonatal cerebral hemorrhage# To differentiate cystic and solid nodule in thyroid# Screening of rotator cuff injury# Pleural effusion# Gallstones, CHPS, ascitis (Minimal), Pelvic abscess# Developmental dysplasia of hip (DDH)/ CDH# Scrotal lesions


Question: NMR based in the principle of

NMR stands for Nuclear Magnetic Resonance. MRI is based on the ability of a small number of protons within the body to absorb and emit radio wave energy when the body is placed in the strong magnetic field.


Question: Dye used for myelography

contrast agents used for myelography are : Iohexol Iopamidol Metrizamide Myodil


Question: Bare orbit sign is a feature of

Bare Orbit sign is seen in cases of NF-1 and is due to sphenoid Dysplasia especially Greater wing of sphenoid, with Absent innominate line on frontal skull radiograph NF1 is associated with some characteristic bone dysplasias, including lambdoid sutural dysplasia, thinning of long bone coices and kyphoscoliosis with a high thoracic acute curve. One of the most common is sphenoid wing dysplasia marked by a bone defect which allows herniation of the temporal lobe through the orbit. On plain radiography, this produces the 'empty' or 'bare' orbit.


Question: Gas shadow in hea and vessels are seen in

Robe sign - the presence of a gas shadow within the hea or the greater vessels, seen in cases of fetal death in utero.It is a rare sign caused by postmoem blood degeneration, usually seen 1-2 days after death; and may be seen as early as 12 hours(Ref: Diagnostic Ultrasound by Carol M. Rumack, Stephanie R. Wilson, J. William Charboneau, and Deborah Levine,4thed, page 1090)


Question: The phase of cell cycle, most sensitive to radiation isa) M Phase  b) G2Phase  c) S Phase  d) Early G1 Phase e) G0Phase

Cells are most radiosensitive in late G, and early M phase → especially G2M interphase.


Question: Air under central tendon of diaphragm is

The 'Cupola sign' is seen on a supine chest/abdominal radiograph in the presence of pneumoperitoneum. It refers to non-dependent gas that rises within the abdominal cavity of the supine patient to accumulate underneath the central tendon of the diaphragm in the midline.


Question: Radiological feature of ischemic colitis is


Question: MRI magnetic field strength is measured in units of

(A) Tesla # tesla (symbol T) is the SI derived unit of magnetic field B (which is also known as "magnetic flux density"). One tesla is equal to one weber per square meter. This SI unit is named after Nikola Tesla. 1 tesla is equivalent to: 10,000 (or 104) G (gauss), used in the CGS system. Thus, 10 G = 1 mT (millitesla), and 1 G = 10-4 T.> The Hounsfield unit (HU) scale is a linear transformation of the original linear attenuation coefficient measurement in one in which the radiodensity of distilled water at standard pressure and temperature (STP) is defined as zero Hounsfield units (HU), while the radiodensity of air at STP is defined as -1000 HU.> For a material X with linear attenuation coefficient ?X, the corresponding HU value is therefore given by where is the linear attenuation coefficient of water.> Thus, a change of one Hounsfield unit (HU) represents a change of 0.1% of the attenuation coefficient of water since the attenuation coefficient of air is nearly zero.> It is the definition for CT scanners that are calibrated with reference to water.# Tissue CT number (HU) Bone 1000 Liver 40 - 60 White matter -20-30 HU Grey matter -37-45 HU Blood 40 Muscle 10-40 Kidney 30 Cerebrospinal fluid 15 Water 0 Fat-50--100 Air-1000> rad is a unit of absorbed radiation dose. It was restated in SI units in 1970 as the dose causing 0.01 joule of energy to be absorbed per kilogram of matter.> Megahertz is a frequency measurement unit used for Ultrasound crystals.


Question: "Signet ring appearance” on CT is seen in

Bronchiectasis may result from an infection or medical condition, such as pneumonia or cystic fibrosis. Mucus builds up and breeds bacteria, causing frequent infections.
Symptoms include a daily cough that occurs over months or years and daily production of large amounts of phlegm.
Treatment may include physiotherapy and medication, such as antibiotics and drugs to help loosen mucus.


Question: The thresholds for permanent sterility in men for an acute exposure and prolonged exposure conditions are

Studies of patients receiving radiation therapy indicate that permanent sterility can result from 2.5 to 3 Gy (250-300 rad) in a fractionated regime over 2 to 4 weeks. The induction of sterility by radiation in human males does not produce significant changes in hormone balance, libido, or physical capability. The original single-dose data came from the irradiation of prisoners, which showed that a dose in excess of 6 Gy (600 rad) is needed to result in permanent sterility. In contrast to most organ systems, where fractionation of dose results in sparing, fractionated courses cause more gonadal damage than a single doseReference: Eric J Hall Textbook of Radiobiology for Radiologist; 5th edition


Question: Earliest congenital malformation that may be detected on USG is

C i.e. Anencephaly Neural tube defects (NTDs) i.e. anencephaly, meningomyelocele, encephalocele and spina bifidaQ can be caused by antifolate & antiepileptic drugs, maternal diabetes, lower maternal folate status, reduced activity of 5, 10, methylene - THE reductase (MTHFR) enzyme (d/t C677 T-polymorphism in MTHFR gene) and possibly by mutation of other enzymes eg. methionine synthase and serine-glycine hydroxymethylase. Folate supplementation at the time of conception and in first 12 weeks of pregnancy reduce 70% incidence of NTDs (and also hare lip and cleft palate). - Neural tube defects are best detected by amniocentesisQ. Earliest detectable congenital anomaly on USG is anencephalyQ. It can be diagnosed as early as at 10 weeksQ. It is best diagnosed (100% accuracy) at 12 week.Q - Karyotypic analysis (for chromosomal abnormalities), biochemical & molecular analysis of DNA obtained from cells can be done in either chronic villi of 1,, trimester or amniotic fluid of 2nd fetus. Test Done at Comment Amniocentesis 14-16 weeksQ - M.C. used procedure; M.C. reason to perform this is advanced maternal age (removal of small (early 2nd (>35 yrs), the best known correlate of trisomy amount of amniotic trimester) - Other reasons are ? fluid) 1. Abnormal (maternal serum) triple marker assayQ (HCGQ, a-FetoproteinQ and unconjugated estriolQ in maternalQ serum) and inhibin also (in quad marker assay) predict risk of trisomy 21 or 18 2. Mid trimester USG abnormalitiesQ - estimated risk of chromosomal abnormality is dependent on USG finding & is maximum in cystic hygromaQ >Omphalocele > congenital hea ds > nonspecific > choroid plexus cyst 3. More recently, 1, trimester screening involving measurement of nuchal translucency (on USG) and levels of PAAP-A and HCG are used to identify women at increased risk. Early Amniocentesis 12-14 weeks Has greater risk of spontaneous aboion or fetal injury but provides results at an earlier stage of pregnancy Chrionic Villus Earlier (8-12 - 2nd m.c. procedure. It allows for an earlier detectionQ of abnormalities & a safer Sampleing (CVS) wks)Q pregnancy termination (d/t early diagnosis), if desired (Transcervical/ preferably 10-12 - Spontaneous aboions are more common in comparison to amniocentesis but is abdominal biopsy of wks. overall a safe procedure (spontaneous aboions fetal trophoblastic - Risk of limb defectsQ increases if CVS is doneweeks.So it is applicable tissue/chorion) during very narrow window of time Percutaneous 2nd -- 3.1 trimester - Done under USG control. Usually performed when USG abnormalities are Umbilical Blood of pregnancy detected late in 2,,d trimester. Sampling (PUBS) (> 18 wks) - Also done to clarify cytogenetic results of amniocentesis as detection of (fetal blood for lvmphocvtic culture) mosaicism. Pre implantation Before implant- To detect single gene disorder such as -Mn : "SC ST" molecular diagnostic ation invitro S - Sickle Cell Anemia testing (eg- PCR) feilizationQ at C - Cystic fibrosis 8-10 cell stage ST - Sachs-Tay disease (Tay-Sachs ds) * Endometrial biopsy is done at Premenstrual periodQ to avoid risk of endometriosis. Chordocentesis is done at 18 wee Q. Amniocentesis is not useful in cleft lip detection. Golden Amniotic fluid is diagnostic of Rh incompatibilityQ. Saffron coloured meconium is seen in post maturityQ.


Question: Driven snow appearance is seen in

Driven snow appearance  - Pindborg tumor.
Fallen fragment sign - Simple bone Cyst.


Question: Extra mammary Paget's involves

(A) Vulva[?]Paget's Disease of the Vulva:Also known as extra mammary Paget's Disease.Represents close to 1% of all vulvar cancers.Occurs in the late reproductive & post menopausal age group.Presents as pruritic & burning, red, crusted patches interspersed with white & ulcerated areas.Can be very extensive & multifocal.>95% of cases it is confined to the epidermis, considered a primary cutaneous in-situ adenocarcinoma arising from either pluripotential cells or from sweat glands.<5% of cases it represents secondary vulvar skin involvement by a regional cancer.Microscopically it is characterized by an intraepithelial proliferation of malignant cells with vesicular nuclei & cytoplasmic mucin.In about 30% of cases it can invade the dermis.It is very difficult to excise & tends to recur.If it invades the dermis for a distance of more than 1mm it has metastatic potential.Paget's Disease:A rare extra mammary disease.Apocrine sweat glands are involved.Slighted elevated, sharply demarcated, white indurated/eczematous lesion found in post-menopausal woman do pruritis.Biopsy reveals typical large pale vacuolated cells in epidermis. These Paget's cells are adeno carcinomatous mucus secreting round cells with vesicular nucleus and pale cytoplasm.Treatment - Vulvar Paget's Disease:Local excision or vulvectomy depend upon the extent of disease.Poor prognostic markers: Greater depth of invasion & lymphovascular involvement.Moh's micrographic surgery: Lower recurrence rate.RT or C/T?Long-term F/U (high risk of recurrence)Annually inspection of vulva & survey tumors at other site (breast, lung, colorectum, gastric, pancreas, ovary)[?]Extramammary Paget's Disease:This is rare lesion of the vulva and some times the perianal region & presents as a pruritic, red, sharply demarcated, area.Most commonly affects the Labia majora:-In contrast to Paget's disease of the nipple, in which 100% of patients show an underlying ductal breast carcinoma, vulvar lesions are most frequently confined to the epidermis of the skin.[?]Extramammary Paget's Disease (EMPD):Like that of breast, is essentially a form of intraepithelial carcinoma.Unlike breast, vulvar Paget's disease have no demonstrable underlying carcinoma.Microscopically, red, scaly plaque; characterized by spread of malignant cells within the epithelium, occasionally with invasion of underlying dermis.It is a rare, slow-growing, usually noninvasive intra-epithelial (in the skin) adenocarcinoma outside the mammary gland and includes Paget's disease of the vulva and the extremely rare Paget's disease of the penis.


Question: Xeroradiography is used in detection of

Xeroradiography is the technology for recording radiographic images without the need for any chemical processing whatsoever. To make an image a selenium photoreceptor, or plate is charged to a uniform surface potential on the order of 1000 volts. When this photoreceptor is exposed to x-rays, its surface charge is depleted by photoconduction in amounts propoional to the radiation intensity striking it. A residual potential pattern which is a shadowgraph of the object being x-rayed is then formed. After exposure, the electrostatic image on the plate is developed by a powder cloud technique in which charged, pigmented paicles are blown over the plate and adhere to it in the pattern of the image. This powder or toner is the ink which defines the image. Following development, the toner is transferred to paper and fixed into a permanent image by low-temperature heat fusing. It requires more radiation exposure. Historically used in mammography prior to the advent of digital mammographyXeromammography is a form of xeroradiographyDental xeroradiography has peculiar positive propeies which enable both detailed bony and soft tissue examination, as well as subtle visualization of structures(Ref: Proc. SPIE 0026, Quantitative Imagery in the Biomedical Sciences I, 71 (June 1, 1971);doi:10.1117/12.975328, Xeroradiography-Principles and practice By Wm. J. Kearns, Christensen&;s Physics of Diagnostic Radiology, chapter 18)


Question: Dili. SLAinks 101

Ans. a. Breast Imaging Repoing and Data System BIRADS stands for Breast Imaging Repoing and Data System BIRADS (Breast Imaging Repoing And Data System) Category Definition 0 Incomplete assessment, need additional imaging evaluationQ 1 Negative, routine mammogram in 1 year is recommendedQ 2 Benign findings, routine mammogram in 1 year is recommendedQ 3 Probably benign findings, sho term follow-up suggestedQ 4 Suspicious abnormality, biopsy should be consideredQ 5 Highly suggestive of malignancy, appropriate action should be takenQ 6 Known biopsy-proven malignancy


Question: Functional analysis of kidney is best done by


Question: Hot nodule in a liver scan is due to

50% of the focal nodular hyperplasia shows the presence of Kupfer cells (phagocytes). So uptake of sulfur colloid is noted in these lesions. No uptake is seen in HCC, hepatic adenoma, and metastases.


Question: The radioisotope used for ablation of thyroid gland is


Question: Investigation of choice to demonstrate vesico ureteral reflux

B i.e. Contract MCU - Patients with suspected urolithiasis (stone) present with painful hematuria and /or recurrent UTI. Ultrasound and KUB X-ray are the initial screening modalityQ followed by unenhanced (i.e. non contrast) helical or spinal CT (imaging modality of choice) if screening is negative. However, IVU (intravenous urography) or IVP is still the best investigation if CT is not available. The test of choice at most centers for diagnosing an acute stone is a non contrast helical CT ScanQ. Helical CT (Non contrast) has the advantage of detecting uric acid stones in addition to the traditional radioopaques stones, and CT does not expose the patient to the risk of radio contrast agents. - Calcification is best detected by CTscanQ. MRI and PET scan have no role in diagnosing renal stone. Intravenous urography (IVP) is the only method which can detect early renal tuberculosis and papillary necrosis. It is the most sensitive and investigation modality of choice for early renal TB. However in advanced cases it should be integrated with cross sectional CT imagesQ. Micturating/Voiding cystourethrography is the best method to visualize posterior urethra, posterior urethral valve & vesico ureteric refluxQ. In post urethral valve,Voiding Cystourethrogram (VCU) shows dialation of prostatic urethra & filling defect corresponding to the valve. VU Reflux occurs when urinary bladder contracts so contrast studies of urinary bladder done during micturation is best way to see VU Reflux. Radionucleotide cystogram is Inv of 2nd choice. It's advantage is that it avoids the need for bladder catheterization. The disadvantage is its lack of anatomical detail. So it may be useful in follow up (not initial assessment).


Question: Great Hilar Dance on Fluoroscopy is a feature of

*Great Hilar Dance is Vigorous pulmonary aerial pulsations seen due to increased blood flow, seen fluoroscopically in patients with Atrial septal defects.


Question: Thumb print sign is seen in

Thumb printing: Indentation in contrast or air-filled bowel lumen caused by sub mucosal infiltration and resembling a thumb printing; e.g. Ischemia Thumbprinting is a Radiographic sign of large bowelwall thickening, usually caused by edema, related to an infective or inflammatory process ('colitis'). The normal haustra become thickened at regular intervals appearing like 'thumb-prints' projecting into the aerated lumen.


Question: Radiation dose is measured in

Units for Radiation dose or absorbed radiation are : Traditional unit : Rad SI unit : Gray


Question: The 'String of beads' or sausage appearance of the renal aery is due to


Question: Lead pipe appearance is seen in


Question: Intercavitatory radiotherapy is treatment modality for

Intracavitary brachytherapy is used most commonly in patients with cancer cervix after radiation therapy has been completed.


Question: Neural tube defect is best detected by


Question: Apical root fracture is visible in


Question: Finger in glove sign is seen in

The finger in glove sign can be seen on either chest radiograph or CT chest and refers to the characteristic sign of a bronchocoele. The same appearance has also been referred to as:rabbit ear appearancemickey mouse appearancetoothpaste shaped opacitiesY-shaped opacitiesV-shaped opacitiesThe finger-in-glove sign is the chest CT/radiographic finding of tubular and branching tubular opacities that appear to emanate from the hila, said to resemble gloved fingers.The tubular opacities represent dilated bronchi impacted with mucus. The CT finger-in-glove sign is branching endobronchial opacities that course alongside neighboring pulmonary aeries. The finding is classically associated with allergic bronchopulmonary aspergillosis (ABPA), seen in persons with asthma and patients with cystic fibrosis, but may also occur as an imaging manifestation of the endobronchial tumor, bronchial atresia, cystic fibrosis, and postinflammatory bronchiectasis.Bronchoscopy may be necessary to exclude endobronchial tumor as the cause of the finger-in-glove sign. The tubular opacities that occur in ABPA result from hyphal masses and mucoid impaction and typically affect the upper lobes( Ref: AJR:202, March 2014, Walker et al.Imaging Pulmonary Infection: Classic Signs and Patterns)


Question: Mount Fuji sign is a feature of

Mount Fuji sign refers to the presence of gas (pneumocephalus) between the tips of the frontal lobes with a heaped-up appearance giving the appearance of Mount Fuji or M like appearance.


Question: The technique employed in radiotherapy to counteract the effect of tumour motion due to breathing is known as

Gating Respiratory gating : It is a technique in radiotherapy in which the radiation is applied during that phase of respiratory cycle in which the tumour is in the best range. This is to prevent unnecessary radiation exposure to normal structures.


Question: Radiation produces its effect on tissue by

C i.e. Charring of nucleoprotein Radiotherapy is treatment of malignant tumors with ionizing radiation (m.c. y rays)Q ; which causes excitation or ionization (ejection of electron from orbit) of electronQ and kills tumor cells by producing double strand breaks in DNA (direct) or free radicles (indirect). So ionizing Radio Therapy acts (on tissue) by- Excitation of electron (to higher energy levels without actual ejection) - and Ionization of electron (Removal of orbital e-). Ionizing radiation is of two types - electromagnetic on) and paiculate radiation. Type Mass Charge Comment Electromagnetic X Ray & y ray do X Ray 0 0 not differ except in Gamma Ray 0 0 the source. y rays are produced intranuclearly and X rays are produced extranuclearly (i.e. mechanical) Paiculate Electron (e) e -1 ? Proton (p) 2000xe +1 Exhibit Bragg peak (most of energy is given abruptly causing ionization) Neutron (n) 2000xe 0 Can't be accelerated by an electrical field Alpha paicle 2p+2n +2 Helium Paicle (8000xe) (2p+2n) - The biological effects produced by a radiation is quantified as relative biological effectiveness (RBE), which compairs them to effects produced by 250KV photon radiation as a standard. - RBE value depends on Linear energy transfer (LET; is amount of ionization occurring per unit length of radiation tract), dose, dose rate & nature of biological system. - Absorption of energy from radiation in tissue leads to ionization &/or excitation leading to various biological effects Q. - Radiation must produce double-strand breaks (not single-strand) in DNA to kill a cell. It can indirectly kill by producing free radicles. - Chromosomal abnormalities occur in cells irradiated in G1 Phase of cell cycle before doubling of genetic material. - Chromatid aberration occurs in cells irradiated in G2 Phase. Most sensitive phase to radiation is M> G2M interphaseQ. Most resistant phase to radiation is end of S phaseQ. Lymphocyte analysis provides evidence of recent total body exposure. -- Ionization radiation (most commonly y rays/X rays) is used for . It causes excitation and ionization of electron from orbit Vt double strand break in DNA (i.e. charring of nucleoprotein) and free radical production in tissueQ.


Question: IoC to detect minimal ascites


Question: Colon cut off sign is seen in

Colon cut off sign - Distension of the colon upto the transverse colon with a paucity of gas distal to splenic flexure - seen in Acute pancreatitis.


Question: The best method to reduce radiation caries is application of

The best method to reduce radiation caries is daily application of a viscous topical 1% neutral sodium fluoride gel in custom-made applicator trays. The best results are achieved from a combination of restorative dental procedures, excellent oral hygiene, a diet restricted in cariogenic foods, and topical applications of sodium fluoride. Patient cooperation in maintaining oral hygiene is extremely important because radiation caries is a lifelong threat. Teeth with gross caries or periodontal involvement are often extracted before irradiation.
Key Concept:
The best method to reduce radiation caries is daily application of a viscous topical 1% neutral sodium fluoride gel in custom-made applicator trays.
White and Pharoah's Oral Radiology Principles and Interpretation 8th edition


Question: A dense renogram is obtained by

C i.e. Rapid (Bolus) injection of dye Dense nephrogram or intensified renal images are obtained (iatrogenically) by - - Rapid/bolus injection of same contrast dose concentration (preferred method)(2. - Increased contrast concentration is less preferred than rapid injection method. The quantity that can be used safely depends on weight & hydration of patient. - Abdominal (ureteric) compression may be used to temporarily obstruct the upper urinary tract but is demanding. - Dehydration method used in past is not used now b/o more chances of precipitation of proteins in renal tubules, obstruction, oliguria & anuria.


Question: Right heart border is mainly formed by

Right heart border: SVC, Rightatrium, Ivc mainly by Right atrium.


Question: Leukodystrophy with Bilateral occipital lobe involvement is seen in

Adrenoleukodystrophy Also known as X-linked Adrenoleukodystrophy, (ALD) is a rare, genetic disorder Characterized by the breakdown or loss of myelin in the brain and progressive dysfunction of the adrenal gland. Adrenoleukodystrophy involves bilateral occipital lobes. Alexanders Disease involves bilateral frontal lobe.it is associated with megalencephaly (large skull). Krabbes Disease - involves Bilateral Thalami


Question: Half value layer refers to

The rate at which an X-ray photon transfer its energy to irradiated matter

The thickness of a substance required to reduce the number of X-ray photons by half

The time taken for X-ray photons to travel half the distance from the source to the object

The heel-effect seen when the anode is placed at an angle to the electron stream in the X-ray cathode tube


Question: Whirlpool sign is feature of

'Midgut volvulus' is a complication of mal-rotated bowel. It may result in proximal bowel obstruction with resultant ischemia if prompt treatment is not instigated. Radiological Findings on CT include: Whirlpool sign of twisted mesentery Malrotated bowel configuration Inveed SMA/SMV relationship Bowel obstruction Free fluid/free gas in advanced cases


Question: 45yr old female with sudden onset headache and neck rigidity There is no history of trauma ..


Question: 'Onion peel' appearance is seen with

Ans. d (Ewing's sarcoma) (Ref.Grainger's Diagnostic Radiology, 4th/pg. 1891)EWING'S SARCOMA# Has specific cytogenetic analysis, i.e., t(11,12) & CD99 positivity. Mic gene +.Q# Histologically, small oval/round tumor cells are seen arranged in sheets with occasional rosette-like pattern and most tumors are PAS-positive indicating presence of glycogen in the tumor cells.# Anaplastic small blue cell malignant tumor . Q# Most common in boys 5-15.# Bone tumor metastasizing to bone. Q# Bone tumor clinically resembling acute osteomyelitis. Q# Commonly appears in diaphysis Q of long bones, pelvis, scapula, and ribs.Radiological features# Ill-defined osteolytic medullary lesion involving diaphysis# Extension along the length of the marrow with permeative bone destruction# Cortical saucerization# Classical multilaminar periosteal reaction giving 'onion-skin' appearance# Codman's triangles with elevated periosteum, although classically seen in osteosarcoma# Soft tissue mass disproportionately large compared to the extent of osseous involvement, resembling osteomyelitisRx:# MRI is investigation of choice# Radiosensitive Q# Extremely aggressive with early metastases, but responsive to chemotherapy.


Question: Bear claw's sign is seen in

Bear claw sign is seen in liver trauma on CECT Note- Bear paw's sign- xanthogranulomatous pyelonephritis.


Question: Pseudoahrosis of Tibia is seen associated with

Pseudoahrosis of the tibia is usually seen associated with NF-1,a false joint between knee and ankle. Sphenoid wing dysplasia is also seen in NF-1. Acoustic Neuromas/Schwannomas are seen with NF-2. Multifocal haemangioblastomas are associated with VHL. Powine stain,leptomeningeal vascular malformations and Tram Track appearanceare seen with Sturge Weber syndrome.