bluuebunny/crossref_metadata_2025 huggingface dataset:
How sensitive is ultrasound in the detection of renal scars?
Authors: Roebuck D J , Howard R G , Metreweli C
Published: June 2014

The English language medical literature was reviewed to determine the strength of the published evidence for the assertion that dimercaptosuccinic acid scintigraphy (DMSA) is superior to ultrasound (US) in the detection of established renal scarring in children. The MEDLINE database was used to identify papers published between 1985 and 1997 that claimed to be concerned with the detection of scars, and contained sufficient information to permit calculation of the sensitivity of US relative to DMSA. Only 10 studies were identified. The sensitivity of US for scarring, using DMSA as a gold standard, ranged from 37% to 100%, and its specificity from 65% to 99%. These wide ranges mean that evaluation of the role of US in the detection of scarring remains controversial. All papers contained methodological flaws. Allowing for these, the sensitivity of US appears to be acceptable. Further research that avoids these methodological problems is required.
Cross-calibration, precision and patient dose measurements in preparation for clinical trials using dual energy X-ray absorptiometry of the lumbar spine.
Authors: Cawte S A , Pearson D , Green D J , Maslanka W B , Miller C G , Rogers A T
Published: June 2014

Large, multicentre clinical trials using DXA to monitor bone density following intervention are now common. At the same time, several different bone densitometers and calibration phantoms are currently in use. The aim of this study was to document the technical information required on cross-calibration of equipment, reproducibility and patient dose before commencing a multicentre clinical trial. To this end, we obtained an in vitro and in vivo cross-calibration of two machines (a Hologic QDR 2000 and a Lunar DPX-L) that were not significantly different. Interobserver and intraobserver precision, and radiation dose were also measured and three commonly used phantoms assessed for their usefulness in cross-calibration and quality assurance. Measured in vitro precision on the two machines (0.3-0.7%) was better than that specified by the manufacturers. In vivo precision was worse (1.4-2.1%), as might be expected in patients with reduced bone mass. Mean entrance skin radiation doses on each machine were 280 microSv for the QDR 2000 and 38 microSv for the DPX-L. No one phantom is ideal, but the European Spine Phantom or Lunar Aluminium Spine Phantom will provide an adequate cross-calibration for a clinical trial. This study demonstrates that an adequate cross-calibration can be obtained for use in groups of patients and that the equipment used is reproducible with a low radiation output.
Fetal position and size data for dose estimation.
Authors: Osei E K , Faulkner K
Published: June 2014

In order to establish both positional and size data for estimation of fetal absorbed dose from radiological examinations, the depth from the mother's anterior surface to the mid-line of the fetal head and abdomen were measured from ultrasound scans in 215 pregnant women. Depths were measured along a ray path projected in the anteroposterior (AP) direction from the mother's abdomen. The fetal size was estimated from measurements of the fetal abdominal and head circumference, femur length and the biparietal diameter. The effects of fetal presentation, maternal bladder volume, placenta location, gestational age and maternal AP thickness on fetal depth and size were analysed. The fetal position from the anterior surface of the mother's abdomen is shorter for posterior placenta and empty bladder volume, but longer for anterior placenta and full bladder volume. Mean fetal depth (MFD) observed for all bladder volumes, fetal presentations and placenta locations increased from 6.5 +/- 0.5 cm to 10.2 +/- 0.7 cm over the duration of pregnancy. Similarly, mean fetal skull depth (FSD) increased from 6.6 +/- 0.6 cm to 9.8 +/- 0.6 cm over the period of pregnancy, but only from about 6.6 cm to 7.8 cm over the period (8-25 weeks) when damage to the developing brain has been observed to result in mental retardation. Using the range of mean fetal depth (4.7-13.9 cm) observed in this study and depth dose data at 75 kVp and 3.0 mmAl half value thickness (HVT), fetal absorbed dose would be overestimated by up to 66% or underestimated by up to 77% if the mean value of MFD (8.1 cm) is used rather than actual individual values. These errors increase with lower tube potential and filtration up to over 90% overestimation and up to 100% underestimation at 60 kVp and 1.0 mmAl filtration.
MRI features of Balo's concentric sclerosis.
Authors: Ng S H , Ko S F , Cheung Y C , Wong H F , Wan Y L
Published: June 2014

We report MRI findings in a 56-year-old woman with Balo's concentric sclerosis (BCS) who initially presented with a progressive hemiparesis. MRI showed two lesions with a concentric pattern in the left frontoparietal region and a laminated, arcuate pattern in the right frontal region. These patterns were best seen in post-contrast images and were consistent with BCS. In addition, there were several small cerebral multiple sclerosis-like plaques. The clinical symptoms improved and the MR findings regressed after corticosteroid therapy. The patient had completely recovered 12 months later, except for mild right hand numbness. MRI showed further regression of the lesions, but the concentric pattern was still present. This case demonstrated that BCS can run a benign prolonged course and may persist for a long time. Concentric or laminated contrast enhancement in the acute phase may suggest that bands of demyelination in BCS occur synchronously rather than successively.
Dissecting vertebral artery aneurysm: diagnosis and coil embolization.
Authors: Coley S C , Clifton A
Published: June 2014

Dissecting aneurysm of the intradural vertebral artery, a rare cause of stroke and sub-arachnoid haemorrhage, is associated with a poor neurological outcome if the disease is unrecognized and remains untreated. Clinical manifestations may be delayed or overlooked and non-invasive radiological investigations demonstrate little or no abnormality. We describe the diagnosis and successful endovascular occlusion of a dissecting vertebral artery aneurysm using detachable microcoils; a novel technique that has advantages over conventional therapeutic procedures.
Diffuse retroperitoneal amyloidosis due to renal cell carcinoma.
Authors: Coakley F V , Hricak H , Presti J C , Small E J
Published: June 2014

The case of a 61-year-old man with haematuria, in whom CT demonstrated a solid renal mass and extensive retroperitoneal infiltration, is presented. This combination of CT findings resulted in significant diagnostic uncertainty. Pathological analysis demonstrated renal cell carcinoma, with secondary amyloidosis in the retroperitoneum. Amyloidosis secondary to renal cell carcinoma has not been previously described as a cause of retroperitoneal infiltration.
Accuracy of intravascular microcatheter pressure measurements: an experimental study.
Authors: Henkes H , Felber S R , Wentz K U , Czerwinski F , Monstadt H , Weber W , Kühne D
Published: June 2014

Intravascular pressure measurements are considered useful for the monitoring and assessment of endovascular treatment effects in intracranial vascular malformations. Experimental data on the accuracy of these measurements are limited. A flow phantom with defined intraluminal pressures and pulsatility flow waveforms was used in this study. Microcatheters commercially available for neuroendovascular procedures (length 140-155 cm), with different outer (0.5-0.83 mm) and inner (0.3-0.53 mm) diameters, were introduced into the phantom in the direction of flow. In a static experiment, pressure values from 0 to 75 mmHg were applied, and in the dynamic part of the experiment mean pressure values from 25 to 65 mmHg, with a pulsatile amplitude from 70 to 170 mmHg were employed. In the static experiment, there was a linear relationship between the pressure values obtained through the microcatheters and the local transducer of the flow phantom. The pulsatile experiments showed increased damping of the pressure waveforms with decreasing inner diameter of the microcatheters. However, the mean pressure values remained accurate. This experimental study has shown that mean pressure values can be accurately measured through microcatheters from 0.3-0.5 mm inner diameter and more than 140 cm in length. In vivo pressure measurements during interventional procedures are therefore reproducible and can be used for monitoring of embolization effects in patients.
Dose reduction during CT scanning in an anthropomorphic phantom by the use of a male gonad shield.
Authors: Price R , Halson P , Sampson M
Published: June 2014

Shielding the radiosensitive gonads during X-ray exposure has been advocated for plain film radiography for many years. In the UK, gonad shields are not widely employed in routine CT scanning, possibly owing to a perceived difficulty in protecting the gonads from a multidirectional X-ray source. The increasing numbers of CT scanners in the UK, with the large doses they deliver to patients, make potential dose reduction methods an important issue. This study measures the dose reduction achievable by shielding the male gonads with a lead wrap-around protection device. The reductions in dose when shielded both from direct radiation and from indirect radiation scattered from local tissues were studied. The use of the device resulted in a statistically significant reduction in the absorbed testicular dose from both direct and scattered radiation, with no increase in the dose measured in surrounding tissues. In three clinically relevant experimental protocols where the testes were not irradiated directly, the testicular absorbed dose from indirect scatter was reduced by 77-93% of the corresponding non-shielded figure. In these three experiments, image quality was unaltered by the use of the shield. A larger dose reduction was obtained when the shield was used to protect the testes from direct irradiation. However, this was achieved at the expense of considerable image degradation from streak artefact that would effectively prevent the clinical use of the device in this setting.
Patient radiation dose during lithotripsy.
Authors: Macnamara A , Hoskins P
Published: June 2014

Measurements were made of the radiation dose to patients undergoing lithotripsy. Two groups were studied; patients undergoing ultrasound localization of calculi, and patients undergoing fluoroscopic localization. Dose area product (DAP) measurements were obtained using a Diamentor ionization chamber. Ultrasound localization produced a mean DAP of 137 cGy cm2 equivalent to a mean effective dose of 0.24 mSv. Fluoroscopy localization produced a mean DAP of 552 cGy cm2 equivalent to a mean effective dose of 1.2 mSv. There was no correlation between stone size and fluoroscopy time. We recommend the use of ultrasound localization as a first option whilst restricting the use of fluoroscopy (preferably pulsed) for ureteric and difficult renal calculi.
Relationships between physical dose quantities and patient dose in CT.
Authors: Hidajat N , Mäurer J , Schröder R J , Nunnemann A , Wolf M , Pauli K , Felix R
Published: June 2014

Patient dose in CT is usually expressed in terms of organ dose and effective dose. The latter is used as a measure of the stochastic risk. Determination of these doses by measurements or calculations can be time-consuming. We investigated the efficacy of physical dose quantities to describe the organ dose and effective dose. For various CT examinations of the head, neck and trunk, organ doses and effective doses were determined using conversion factors. Dose free-in-air on the axis of rotation (Dair) and weighted computed tomography dose index (CTDIw) were compared with the absorbed doses of organs which are located totally within the body region examined. Dose-length product (DLP) was compared with the effective dose. The ratio of the organ dose to CTDIw was 1.37 (0.87-1.79) mSv mGy-1. DLP showed a significant correlation with the effective dose (p < 0.005). The average ratio of effective dose to DLP was 0.28 x 10(-2) mSv (mGy cm)-1 for CT of the head, 0.62 x 10(-2) mSv (mGy cm)-1 for CT of the neck and 1.90 x 10(-2) mSv (mGy cm)-1 for CT of the trunk. CTDIw and DLP can be used for estimating the organ dose and effective dose associated with CT examinations of the head, neck and trunk.
Evaluation of a MOSFET radiation sensor for the measurement of entrance surface dose in diagnostic radiology.
Authors: Peet D J , Pryor M D
Published: June 2014

A patient dosimetry system using MOSFET technology (Thomson and Neilson Electronics Ltd, Canada) is evaluated for entrance surface dose measurements in diagnostic radiology. The system sensitivity for the standard MOSFET detector coupled to a high sensitivity bias supply was measured to be 1 mV mGy-1. Response of a new high sensitivity dosemeter was measured to be 3 mV mGy-1. The minimum detectable entrance surface dose at which a single measurement can be made with less than 25% total uncertainty at the 95% confidence level was estimated to be 4 mGy for the standard dosemeter and 1.5 mGy for the new high sensitivity dosemeter. The dosemeters were found to be linear with absorbed dose in air, linear with dose rate and reproducible, although they showed some energy dependence across the diagnostic energy range. The system is also compared with thermoluminescent dosimetry (TLD) as a tool for the measurement of entrance surface dose in diagnostic radiology. MOSFET detectors are considered to have advantages over TLD dosemeters with the instant readout of entrance surface dose. These dosemeters do have the disadvantage that they are visible in radiographs, they have a finite shelf life and can only accumulate absorbed dose up to a limiting value after which the dosemeters can no longer be used.
CT determination of bone mineral density and structural investigations on the axial skeleton for estimating the osteoporosis-related fracture risk by means of a risk score.
Authors: Andresen R , Haidekker M A , Radmer S , Banzer D
Published: June 2014

In addition to the pure measurement of bone mineral density (BMD) in osteodensitometry, the investigation of bone structure is becoming increasingly important for estimating fracture risk. In a clinical study, a risk score was proposed which separately assesses BMD and structural parameters for spongious and cortical bone and aggregates them into a single diagnostic parameter. In 120 lumbar vertebrae from 40 patients, BMD was determined separately for spongious and cortical bone by means of quantitative CT using a single energy procedure (SE-QCT/85 kV). In addition, structural parameters based on high resolution CT were calculated for the spongiosa and cortical bone. For all patients the number of osteoporosis-related fractures was determined on the entire skeletal system. According to WHO criteria, the patients were subdivided into four groups: 1, normal; 2, osteopenic; 3, osteoporotic without fractures; 4, severely osteoporotic. Weighting factors were determined by means of multivariate least-squares analysis and used to calculate a risk score of all parameters. The ability of the individual parameters and of the sum of discriminate between the individual groups was tested. If one considers the individual parameters (BMD and the fractal structural values for spongious and cortical bone), they allow a statistically significant separation of the four groups, although there is overlapping in the value ranges. In patients with fractures, there was a significant reduction in the cortical mineral density, accompanied by a deterioration in structural properties. The following individual values were obtained (minimum-mean-maximum): spongiosa BMD (mg ml-1), unfractured: 62-112-163, fractured: 9-48-77; cortical BMD (mg ml-1), unfractured: 190-287-405, fractured: 133-191-269; spongiosa structural parameter, unfractured: 0.35-0.73-1.01, fractured: 0.95-1.24-1.58; cortical structural parameter, unfractured: 18-31-65, fractured: 21-44-66. Above 77 mg ml-1 CaHA in the spongiosa and 270 mg ml-1 CaHA in cortical bone, no fractures were observed. By appropriately selecting the weighting factors, the score is free of overlapping between the groups with and without fractures (values: unfractured 1-9-15, fractured 16-21-29). With higher score values, the fracture risk is increasing.
Anomalies in dual energy X-ray absorptiometry measurements of total-body bone mineral during weight change using Lunar, Hologic and Norland instruments.
Authors: Tothill P , Laskey M A , Orphanidou C I , van Wijk M
Published: June 2014

A previous study showed that measurements of total-body bone mineral changes made with a Hologic QDR 1000W were unreliable when the subjects underwent weight change. The study has been extended to dual energy X-ray absorptiometry (DXA) apparatus from other manufacturers. Re-analysis of published results during weight loss using a Lunar DPX showed that they varied with the software used. Using the Extended mode, there was a 1% loss of bone mineral areal density (BMD), but no significant change in bone mineral content (BMC) or bone area (BA) following a weight loss of 16 kg, whereas the use of the Standard mode led to a larger fall of BMC and BMD. Similar findings arose from the consideration of two studies using Norland XR 26 HS absorptiometers. On the other hand, separation of two groups with similar weight changes from the population studied with a Hologic QDR 1000W confirmed that BMC changed directly with weight, but there was an inverse relationship for BMD, owing to an inappropriate change of BA. The use of Hologic Enhanced and Standard software modes led to significant differences in initial readings and measured changes. With each instrument there was a strong correlation between changes in BA and changes in BMC. When 6 kg of lard was wrapped around the limbs of volunteers or a semi-anthropomorphic phantom to simulate weight change, there were spurious increases of measured BMC and BA by about 5% with each instrument. There were no changes of BMD with Lunar, variable results with Norland, but decreases with Hologic. The results observed in vivo could be explained by the effects of fat changes, without there being any real change of bone mineral. Changes of BMD in the skeleton of the phantom were underestimated with all three brands. The anomaly observed with the Hologic QDR 1000W is less apparent with a Lunar DPX or a Norland XR 26, but there are sufficient uncertainties for all total-body measurements during weight change to be treated with suspicion.
Accuracy of alignment in breast irradiation: a retrospective analysis of clinical practice.
Authors: Pradier O , Schmidberger H , Weiss E , Bouscayrol H , Daban A , Hess C F
Published: June 2014

The objective of the study was to determine the accuracy of patient positioning in radiotherapy for breast cancer. Portal images were obtained using a fast electronic megavoltage radiotherapy imaging system in 30 cases of breast cancer. Quantitative analysis of 530 megavolt portal images and comparison with 30 digitized simulation films were performed. Five linear measurements were taken for each simulation and verification film. Central lung distance (CLD) is the distance from the dorsomedial beam edge to the inner thoracic wall in the central plane of the beam. Cranial lung distance (CrLD) is the distance from the dorsomedial beam edge to the inner thoracic wall in the plane of the beam at 4 cm from the central plane. Central beam edge to skin distance (CBESD) is the distance from the skin to the ventrolateral beam edge in the central plane of the beam. The central irradiated width (CIW) is defined as the distance from the dorsomedial beam edge to the skin. The craniocaudal distance (CCD) is defined as the distance from a particular landmark to the caudal field border. Concerning patient position in the field, mean standard deviations of the difference between simulation and treatment images were 3.9 mm for the CLD, 3.2 mm at +4 cm, 3.6 mm for the CIW, 3.3 mm for the CBESD, 3.8 mm for the CCD. In 90% of all set-up for treatment, errors were less than 1 cm. The variation of the CLD was the largest set-up error. This parameter is clinically the most significant. Future treatment delivery should be improved by introducing patient positioning devices such as thermoplastic shells. The electronic portal imaging device (EPID) appears to be an adequate tool to study the accuracy of treatment set-ups like this.
Pulmonary sequestration diagnosed by contrast enhanced three-dimensional MR angiography.
Authors: Au V W , Chan J K , Chan F L
Published: June 2014

Pulmonary sequestration is a congenital bronchopulmonary foregut malformation in which a segment of lung parenchyma is not connected to the tracheobronchial tree. This abnormal segment receives a blood supply from the systemic circulation. Multiple imaging modalities have been used to demonstrate the vascular anatomy of the sequestration. Different magnetic resonance angiography (MRA) techniques have been employed in the identification of these anomalous vessels. We report a case of pulmonary sequestration diagnosed by MRI with the use of contrast enhanced three-dimensional MRA.
Systemic to pulmonary venous communication (right-to-left shunt) in superior vena cava obstruction demonstrated by spiral CT.
Authors: Ho H T , Horowitz A L , Ho A C
Published: June 2014

An unusual case of systemic vein to pulmonary vein communication in superior vena cava obstruction is reported. This was a right-to-left shunt, demonstrated by spiral CT and aided by three-dimensional reconstruction. The pulmonary venous shunts were mainly seen in fibro-atelectatic lung where prominent bridging veins were concentrated.
Growing skull fracture extending posteriorly to the superior sagittal sinus with intradiploic extension.
Authors: Lenthall R , Penney C
Published: June 2014

An intradiploic extension of a post-traumatic encephalocoele is described in an infant.
MRI of head and neck paracoccidioidomycosis.
Authors: de Castro C C , Benard G , Ygaki Y , Shikanai-Yasuda M , Cerri G G
Published: June 2014

Paracoccidioidomycosis, caused by the dimorphic fungus Paracoccidioides brasiliensis, is the most important systemic mycosis in Latin America. Imported cases have been reported in North America, Asia and Europe, in individuals who lived in endemic areas, sometimes many years before the development of clinical manifestations. The disease causes cutaneous and/or respiratory tract mucosal lesions as well as lymph node enlargement. Involvement of the oropharynx and/or the larynx, either alone or in association with pulmonary involvement, is one of the commonest clinical presentations. On MRI, the major features are mucosal lesions, usually hypointense on T1 weighted images and hyperintense on T2 weighted or fat suppressed images, affecting the oral cavity, oropharynx and larynx, with head and neck lymph node enlargement. Differential diagnosis includes other granulomatous infectious diseases, especially tuberculosis, and cancers such as squamous cell carcinoma and lymphomas.
Geometry of proximal femur in the prediction of hip fracture in osteoporotic women.
Authors: Gnudi S , Ripamonti C , Gualtieri G , Malavolta N
Published: June 2014

111 White post-menopausal women with hip fracture and 329 healthy controls were studied in order to determine whether proximal femur geometry predicts hip fracture and improves the discriminant ability of femoral neck bone mineral density (BMD) in elderly women. All subjects underwent dual X-ray photon absorptiometry (DXA) of the hip from which the femoral neck BMD, hip axis length, femoral neck width and femoral neck-shaft angle were measured. Fractured subjects had a lower femoral neck BMD, a longer hip axis length and a more valgus neck-shaft angle. The hip axis length correlated significantly with neck-shaft angle, femoral neck width and age. No significant correlation was found between neck-shaft angle and age. On standardized logistic regression, the hip axis length and the neck-shaft angle predicted fracture independently of BMD after correction for age, weight and femoral neck BMD. The femoral neck BMD significantly discriminated fractured subjects after correction for all potential confounders. The logistic models containing simultaneously one femoral geometric parameter and the neck BMD discriminated significantly better than those containing the same variables as single predictor. Our data suggest that hip axis length may play a role in fracture risk and supports a similar role for neck-shaft angle. Combining proximal femur geometric measurements and femoral neck BMD improved the discriminant ability of each measurement.
Half value layer measurements to facilitate patient dose assessment for newer CT scanners using published normalized dose data.
Authors: Hill A L
Published: June 2014

The National Radiological Protection Board (NRPB) method of calculating patient doses from CT can be applied to scanners not represented in normalized dose data sets, published in NRPB Report R250, if an appropriate existing data set is selected. A method of matching scanner models to data sets is currently being developed in a national scanner survey, organized by the Department of Health ImPACT CT evaluation group. This paper demonstrates the use of an alternative method of data set selection to that employed in the national study, by application to the Picker PQCT and Siemens +4 scanners. Half value layers (HVLs) evaluated at the isocentre and at intervals within the fan angle of the X-ray beam of either the Picker PQCT or Siemens +4 were compared with HVLs for three scanner models represented in the NRPB data sets. A good match indicates the suitability of a normalized dose data set, since data sets are dependent on the quality of the X-ray beam incident on a patient. The results demonstrate that Picker 1200SX data sets could be used with the Picker PQCT scanner. The most likely match for the Siemens +4, from the limited number of scanners investigated, was identified as being the Philips Tomoscan LX.
Real-time portal monitoring to estimate dose to skin of patients from high dose fluoroscopy.
Authors: Wagner L K , Pollock J J
Published: June 2014

Since doses to skin of patients from fluoroscopically-guided interventional procedures can be very high, real-time monitoring of skin dose is important for both patient management and quality control. The use of a scintillation detector, placed on the X-ray port to measure potential skin dose, was investigated, focusing on the uncertainties related to the technique. Sources of uncertainty include performance characteristics of the dosemeter, errors in calibration, patient set-up and changes during the procedure. Some of the largest sources of error include uncertainty in source-to-skin distance, heel effect, difficulty in identifying the area of skin principally exposed, calibration error, energy dependence of the dosemeter and the dose rate dependence of the monitor. This technique is found to be beneficial for radiation management, but users must be cognizant of the potential errors of the method and the limitations that these place on quality control and patient management. Knowing the limitations and minimizing the sources of error enhance the utility of the technique.
The effect of region of interest selection on dual energy X-ray absorptiometry measurements of the calcaneus in 55 post-menopausal women.
Authors: Kang C , Speller R
Published: June 2014

Bone mineral density (BMD) of the calcaneus was assessed by dual energy X-ray absorptiometry (DXA) in four different regions of the calcaneus in 20 pre-menopausal and 55 post-menopausal women, none of whom were on treatment or suffering from conditions affecting bone. The total body option in the small animal software package of a Lunar DPX-L bone densitometer was used. The precision of the technique (%CV) varied from 0.7 to 2.2% depending on the region scanned. For post-menopausal women, BMD results in the mid and posterior parts of the calcaneus varied by < 7% while BMD in the anterior region was about 20% lower. DXA of the calcaneus was compared with measurements at the spine (L2-L4) and hip (femoral neck) and changes with age were estimated from cross-sectional data. BMD of the calcaneus was significantly reduced in 28 post-menopausal women with low lumbar spine BMD (-2SD) compared with women with normal spine BMD. Calcaneal BMD was significantly correlated to axial BMD (r = 0.45-0.77) and to age (r = 0.45 to -0.63). For a subgroup of 33 post-menopausal women measured twice after approximately 1 year, calcaneus BMD decreased by between 1.2% and 2.5% while axial BMD showed no significant change. Unlike spine or femoral neck BMD, the decrease in calcaneus BMD was significantly greater in women with low spine BMD than in normal women, possibly indicating improved detection of skeletal changes. The optimum measurement sites for BMD in the calcaneus were within the mid or posterior part of the calcaneus or enclosing the whole posterior calcaneus. The calcaneus was shown to be a precise, sensitive and simple measurement site suitable for the assessment of osteoporosis, especially in the elderly where degenerative changes in the spine and hip can complicate BMD assessment.
In the radiotherapy of prostate cancer, technique determines the doses to the penile structures.
Authors: Vijayakumar S , Myrianthopoulos L C , Dabrowski J , Pelizzari C A , Rosengarten J , Nguyen A , Vaida F , Chen G T
Published: June 2014

For 11 consecutive prostate cancer patients undergoing three-dimensional conformal radiotherapy (3DCRT) in our institution, penile structures (PNS) were outlined in CT images obtained for treatment planning purposes. Dose-volume histograms (DVHs) were compared in order to study dose-volume relations for three techniques: 4FLD, an axial coplanar, four-field box technique; 6FLD, a six-field coplanar technique; and 4NAX, a coplanar but non-axial, four-field technique. All three techniques delivered equal doses to the planning target volumes (PTV). Our statistical analyses strongly indicate that the three techniques can be ranked as 6FLD better than 4FLD (and 4FLD better than 4NAX) as far as irradiating PNS volume during treatment of prostate cancer (PC) is concerned. For each technique, there is a "spread" owing to differences in patient anatomy and/or target size, position, and extent, but each technique has a similar "profile" or "shape" distinct from other techniques. Whether irradiating smaller volumes of PNS will influence the sexual potency outcome remains to be demonstrated. However, PNS should be considered as another critical structure in addition to rectum, bladder and femoral heads in the radiotherapy (RT) of PC, especially in 3DCRT dose escalation studies. Sexual potency outcomes can be correlated to dose-volume relations in the future and this will help refine radiotherapy techniques further.
Imaging features of focal intrahepatic extramedullary haematopoiesis.
Authors: Wong Y , Chen F , Tai K S , Yip L K , Tsang K W , Chan F L , Ooi G C
Published: June 2014

The imaging findings of focal intrahepatic extramedullary haematopoiesis (EMH) in a 51-year-old woman with beta-thalassaemia intermedia are described with particular reference to MRI and CT. Bone marrow colloid scintigraphy was unhelpful in confirming the diagnosis, which was made from fine needle aspiration. This is the first description of stellate scars occurring in an EMH lesion. A review of the radiological appearances of this rare condition is presented.
Features of unusual metastases from prostate cancer.
Authors: Long M A , Husband J E
Published: June 2014

A retrospective study of CT examinations on 508 patients with prostate carcinoma was performed in order to document the presence or absence of uncommon nodal and extranodal metastases according to pre-defined criteria. 45 atypical metastases were demonstrated in 36 patients. There were 23 atypical nodal metastases including unusual distribution (19/23), large volume (7/23) and atypical morphology or contrast enhancement pattern (8/23). 22 atypical extranodal metastases included orbit/skull base (11), pulmonary (4), liver (3), intracranial (2), ocular (1) and adrenal (1). Atypical prostate carcinoma metastases are usually encountered in the presence of known advanced disease but can be the presenting feature of malignancy or the only sign of distant spread. Knowledge of atypical manifestations of metastatic disease will reduce diagnostic delay, allow accurate staging and lead to the effective and timely delivery of appropriate treatment.
Ultrasound guided fine needle aspiration biopsy of splenic lesions.
Authors: Venkataramu N K , Gupta S , Sood B P , Gulati M , Rajawanshi A , Gupta S K , Suri S
Published: June 2014

Fine needle aspiration biopsy (FNAB) of focal splenic lesions has been infrequently utilized because of the risk of haemorrhage. This study was carried out to evaluate the safety and efficacy of ultrasound guided FNAB of splenic lesions. 35 patients with focal splenic lesions underwent FNAB under real-time ultrasound guidance using a free hand technique. Ultrasound findings were single or multiple focal hypoechoic lesions (n = 33), focal hyperechoic lesion (n = 1) and diffuse heterogeneous echotexture (n = 1). Aspirations were performed with 22 G spinal needles using either the subcostal or the intercostal approach. Definite cytological diagnosis was made in 22 patients (62.8%), including tuberculosis in 10 patients, lymphoma in seven patients, extramedullary haematopoiesis in two patients and aspergillosis, histoplasmosis and bacterial abscess in one patient each. FNAB was negative in 12 patients because the aspirates were either scanty or contained only blood. FNAB was falsely positive in one patient. Only one patient had significant intraabdominal bleeding, which was managed conservatively. In conclusion, splenic FNAB performed under ultrasound guidance is a safe and accurate method in the diagnosis of focal splenic lesions.
Comparison of adult and paediatric spine and whole body software for the Lunar dual energy X-ray absorptiometer.
Authors: Laskey M A , Prentice A
Published: June 2014

Simple phantoms were devised to compare the performance of adult (software 3.64) and paediatric (software 3.8 g) spine and whole body software developed for the Lunar dual energy X-ray absorptiometer. Rectangular slabs of aluminium with high (1.18 g cm-2) and low (0.57 g cm-2) density were used to represent bone mineral. For spine measurements, the phantoms were scanned in water at depths of 5-20 cm. For whole body measurements, the phantoms were scanned with known amounts of oil and water to represent fat and lean tissue. This simulated tissue depths of 5.5-19.7 cm and body composition ranging from 14-29% fat. There were systematic differences in spine and whole body bone mineral content (BMC), bone area (BA) and bone mineral density (BMD) measurements and also between adult and paediatric software versions. The magnitude and direction of these differences were dependent on BMD of the phantom and tissue depth. Similar systematic differences were observed in vivo when volunteers were scanned using adult and paediatric software. Paediatric software enabled measurements to be made at low tissue depths. The weights of fat, lean and total soft tissue measured by the adult and paediatric whole body software were similar to the values calculated from the known composition of the phantom. Precision estimates for all softwares were excellent. In conclusion, paediatric software should improve bone mineral measurements of children but the discrepancies between adult and paediatric softwares may cause problems in longitudinal studies of skeletal growth and when compiling reference data from infancy through to adulthood.
Radiation doses from CT in the Sultanate of Oman.
Authors: Goddard C C , al-Farsi A
Published: June 2014

The computed tomography dose index (CTDI), dose-length product (DLP) and the effective dose were determined for a range of CT examinations in the Sultanate of Oman. There was a wide variation in CTDI. This shows that there is a variation in both scanner design and the exposure settings used by hospitals. There was also a wide variation in DLP and effective dose, suggesting that in some cases too many slices are taken. Therefore, standard protocols should be designed and adhered to in order that radiation doses may be reduced in the future.
High resolution imaging of transitional cell carcinoma with optical coherence tomography: feasibility for the evaluation of bladder pathology.
Authors: Jesser C A , Boppart S A , Pitris C , Stamper D L , Nielsen G P , Brezinski M E , Fujimoto J G
Published: June 2014

Significant challenges regarding patient morbidity and mortality remain in the management of transitional cell carcinoma (TCC). Among the most important of these challenges is the inability to identify early neoplastic changes and to assess the degree of tumour invasion into the bladder wall in vivo. Optical coherence tomography (OCT) has been recently developed to provide in situ, high resolution, catheter/endoscope based imaging. This study explored the feasibility of OCT for the evaluation of bladder pathology. Both in vitro and in vivo studies were performed. In vitro imaging of pathological human bladder was performed and compared with normal specimens and histopathology. In vivo imaging of normal rabbit bladder was also performed with our current catheter/endoscope based systems. In the in vitro studies, OCT was able to delineate normal microstructure of the bladder, such as the mucosa, submucosa and muscularis layers. This was in contrast to specimens of invasive carcinoma, where a disruption of the normal bladder wall architecture was seen. The in vivo experiment demonstrated current limitations of the catheter/endoscope based systems and provided valuable information for developing an improved system for bladder imaging. The ability of OCT to delineate microstructure of the bladder wall suggests feasibility for endoscopic based imaging. In particular, there is a potential role envisioned for OCT in the management of TCC, identifying pre-malignant states and the depth of tumour invasion.
Contrast enhanced dynamic MRI of cervical carcinoma during radiotherapy: early prediction of tumour regression rate.
Authors: Gong Q Y , Brunt J N , Romaniuk C S , Oakley J P , Tan L T , Roberts N , Whitehouse G H , Jones B
Published: June 2014

This prospective study investigated the relationship between changes in the MRI dynamic enhancement of cervical carcinoma early during radiotherapy, and tumour regression rate throughout radiotherapy. A total of 36 MRI examinations was performed in seven patients with cervical carcinoma, including a T2 weighted sequence weekly during radiotherapy and also a multislice dynamic Gd-DTPA enhanced sequence before and after the first 2 weeks of radiotherapy. Tumour enhancement was determined on dynamic images using a region of interest and signal-to-noise ratio method. Serial tumour volumes over time on T2 weighted images were estimated using the Cavalieri method of modern design-based stereology to obtain tumour regression rate. It was found that peak and mean enhancement prior to radiotherapy ranged from 3.0 to 13.3, and from 1.9 to 12.2, respectively. After 2 weeks of radiotherapy, peak and mean enhancement ranged from 7.5 to 13.0, and from 6.3 to 10.6, respectively. The change in peak and mean tumour enhancement between dynamic scans ranged, respectively, from -2.0 to 8.4 and from -4.5 to 8.5. Tumour volume decreased exponentially with time (p < 0.01). Tumour regression rates ranged from 2.0% to 15.2% per day, and correlated positively with changes of both peak and mean tumour enhancement (p < 0.01). It is concluded that MRI dynamic enhancement during the first 2 weeks of radiotherapy may provide early prediction of tumour regression rate, and therefore be of value in designing treatment schedules for cervical carcinoma.
Rhenium-186 HEDP as a boost to external beam irradiation in osteosarcoma.
Authors: Sawyer E J , Cassoni A M , Waddington W , Bomanji J B , Briggs T W
Published: June 2014

In this case report we demonstrate the usefulness of targeted radiotherapy in the form of rhenium-186 HEDP as a method for dose escalation in the treatment of osteosarcoma.
Imaging appearances of Sister Mary Joseph nodule.
Authors: Coll D M , Meyer J M , Mader M , Smith R C
Published: June 2014

Sister Mary Joseph nodules are metastatic deposits in the periumbilical area. The purpose of this review is to demonstrate umbilical anatomy, discuss modes of metastatic spread, the various imaging appearances and their relevance to the radiologist.
Renal angiography using carbon dioxide.
Authors: Beese R C , Bees N R , Belli A M
Published: June 2014

The many advantages of carbon dioxide (CO2) angiography in the investigation of renal arterial disease include an absence of both nephrotoxicity and allergic reactions. An automated delivery system facilitates injection of CO2 whilst ensuring that there is no contamination of the injection with air. We report our initial experience using a prospective study of this delivery system in 47 patients referred for renal angiography, and assess diagnostic image quality and adverse reactions to CO2 angiography using the automated delivery system. The majority (37/47; 79%) of angiograms were of diagnostic quality and there were no significant adverse reactions in response to the CO2 contrast agent.
Differential bore sheath breast biopsy--a pilot study of a new technique.
Authors: Flanagan J J , Conry B G , Bentley P G
Published: June 2014

The increasing requirement for core biopsy in the diagnosis of early breast disease puts additional demands on radiologists' time and expertise. We present a new approach to percutaneous breast biopsy of impalpable lesions with core biopsy and simultaneous hook wire localization. The technique allows accurate localization of breast lesions and is unique in that it facilitates simultaneous hook wire localization. Percutaneous biopsy by this method was accurate in 9 of 11 patients.
Comparison of an imaging heel quantitative ultrasound device (DTU-one) with densitometric and ultrasonic measurements.
Authors: Diessel E , Fuerst T , Njeh C F , Hans D , Cheng S , Genant H K
Published: June 2014

The purpose of this study was to evaluate a new imaging ultrasound scanner for the heel, the DTU-one (Osteometer MediTech, Denmark), by comparing quantitative ultrasound (QUS) results with bone mineral density (BMD) of the heel and femur from dual X-ray absorptiometry (DXA), and by comparing the DTU-one with another QUS device, the UBA 575+. The regions of interest in the DXA heel scan were matched with the regions evaluated by the two QUS devices. 134 healthy and 16 osteoporotic women aged 30-84 years old were enrolled in the study. In vivo short-term precision of the DTU-one for broadband ultrasound attenuation (BUA) and speed of sound (SOS) was 2.9% and 0.1%, respectively, and long-term precision was 3.8% and 0.2%, respectively. Highest correlations (r) between QUS and BMD measurements were achieved when comparing DTU-one results with BMD in matched regions of the DXA heel scan. Correlation coefficients (r) were 0.81 for BUA and SOS. Highest correlations with the UBA 575+ were 0.68 and 0.72, respectively. The comparison of BMD in different femoral sites with BUA and SOS (DTU-one) varied from 0.62 to 0.69 when including the entire study population. The correlation between BMD values within different sites of the femur tended to be higher (from r = 0.81 to 0.93). When comparing BUA with BUA and SOS with SOS on the two QUS devices, the absolute QUS values differed significantly. However, correlations were relatively high, with 0.76 for BUA and 0.82 for SOS. In conclusion, the results of the new quantitative ultrasound device, the DTU-one, are highly correlated (r = 0.8) with results obtained using the UBA 575+ and with BMD in the heel. The precision of the DTU-one is comparable to other QUS devices for BUA and is high for SOS.
Pseudomembranous necrotizing bronchial aspergillosis.
Authors: Ahn M I , Park S H , Kim J A , Kwon M S , Park Y H
Published: June 2014

We report a case of pseudomembranous necrotizing bronchial aspergillosis in a patient with acute myelocytic leukaemia who died of massive haemoptysis. Lobar collapse was demonstrated on chest radiography. CT showed a marked necrotic thickening of the lobar bronchus with extension of the disease in to the peribronchial region.
The radiological appearances of tuberous sclerosis.
Authors: Evans J C , Curtis J
Published: June 2014

Tuberous sclerosis is an autosomal dominant disorder often associated with a chromosome 9 abnormality, although up to 60% of cases occur spontaneously. The incidence of the disorder is between 1/100,000 and 1/10,000, and it leads to multiple organ and skeletal abnormalities. The classical triad of epilepsy, mental retardation and adenoma sebaceum defines the syndrome clinically. Other cutaneous associations include shagreen patches, ash leaf-shaped areas of depigmentation, subungual fibromas and café-au-lait spots. This review describes the commoner radiological manifestations of the syndrome, and briefly mentions the rarer associations that have been reported to date.
Quantitative ultrasound or clinical risk factors--which best identifies women at risk of osteoporosis?
Authors: Stewart A , Reid D M
Published: June 2014

Dual energy X-ray absorptiometry (DXA) is the current technique of choice to assess risk of future fracture and to diagnose osteoporosis as defined by bone mineral density (BMD). Guidelines for bone densitometry referral have been published listing clinical risk factors that might be considered grounds for assessment. However, these factors are known to be poorly predictive of subsequent BMD measurement and, accordingly, new inexpensive methods of selecting subjects for assessment should be sought. Quantitative ultrasound (QUS) of bone may be such a technique. Women (n = 250) considered by their general practitioners to be at risk of osteoporosis and who had been referred for DXA measurements of the spine and hip were recruited into the study. All underwent a QUS scan of the heel using a McCue CUBA Clinical machine, which measures broadband ultrasound attenuation (BUA) and velocity of sound (VOS), a clinical risk factor questionnaire, and spine and hip BMD measurement by a Norland XR-26 bone densitometer. Patients were categorized according to published diagnostic criteria for BMD, and these were also applied to the QUS parameters. Risk factors were arbitrarily categorized into "low", "medium" and "high" risk groups. Kappa scores were calculated to analyse the agreement between different techniques. Receiver operator characteristic (ROC) analyses were undertaken to demonstrate the technique with the best sensitivity and specificity for the detection of low BMD at the spine and hip. Analysis of the bone mass data demonstrated only moderate agreement (kappa 0.33) between femoral neck and spine BMD with femoral neck BMD and BUA showing a very similar level of agreement (kappa 0.31). ROC analysis demonstrated that VOS followed by BUA was the best predictor of low BMD, with risk factors alone being significantly poorer; QUS parameters are better predictors than clinical risk factors for women with low BMD and could be used effectively at the primary care level to indicate those who should be considered for full osteoporosis assessment. However, further study into the cost effectiveness of this approach is required.