bluuebunny/crossref_metadata_2025 huggingface dataset:
Cervical assessment by magnetic resonance imaging--its relationship to gestational age and interval to delivery.
Authors: Chan Y L , Lam W W , Lau T K , Wong S P , Li C Y , Metreweli C
Published: June 2014

The aim of this cross-sectional study was to assess the uterine cervix in late pregnancy, using MRI, and to study its relationship to the gestational age and the time interval to delivery. 91 women with a singleton cephalic presenting fetus had MRI of the pelvis between 35 and 41 weeks. All had had one prior lower segment Caesarean section and no history of prior vaginal delivery. The cervical length, internal and external os diameter, cervical signal intensity and the angulation of the cervix with the cephalocaudal axis were measured on sagittal T2 weighted images and correlated with the gestational age and the interval from the MRI examination to delivery. It was found that the signal intensity of the cervical stroma increased with the gestational age. A higher signal intensity in the cervical stroma was associated with a shorter time interval to delivery. Deliveries after 40 weeks tended to occur more commonly in those with lower signal intensity in the cervical stroma and also in those with a smaller external os diameter. It is concluded that cervical softening as assessed on MRI correlated with gestational age and the time interval to delivery.
Experiences with functional magnetic resonance imaging at 1 tesla.
Authors: Jones A P , Hughes D G , Brettle D S , Robinson L , Sykes J R , Aziz Q , Hamdy S , Thompson D G , Derbyshire S W , Chen A C , Jones A K
Published: June 2014

Functional magnetic resonance imaging (fMRI) has been performed on a standard 1 T system using a pulse sequence developed to utilize blood oxygen level dependent (BOLD) contrast and an off-line analysis routine using correlation techniques. The sequence and the data analysis routine have been validated by reproducing the conventional hand movement paradigm studies reported by numerous other workers. Our work has then been extended to investigate cerebral foci for a tonic pain stimulus and the cortical representation of oesophageal stimulation. Both these studies relate to paradigms where the expected BOLD signal is significantly less than that encountered for motor or visual cortex paradigms. The results show good agreement with other modalities (positron emission tomography, magnetoencephalography and cortical evoked potentials). Performing fMRI at 1 T is slightly controversial. However, our successful study of demanding paradigms, using a standard clinical 1 T imaging system, has important implications for many other users operating at this field strength.
The practical peak voltage of diagnostic X-ray generators.
Authors: Kramer H M , Selbach H J , Iles W J
Published: June 2014

A new quantity termed the "practical peak voltage" is proposed. This quantity is derived by equating the low level contrast in an exposure made with an X-ray tube connected to a generator delivering any arbitrary wave form, to the contrast produced by the same X-ray tube connected to a constant potential generator. Out of the great number of possible contrast configurations one is selected as being suitable for diagnostic radiology. By means of an eigenvalue problem a direct link is established between the electrical quantity X-ray tube voltage and the practical peak voltage which was initially defined through the properties of the X-ray field. It is shown that the spread in total X-ray tube filtration as encountered in medical diagnostic radiology can influence the result of a measurement of the practical peak voltage only marginally.
Supradiaphragmatic middle aorta syndrome--MR and angiographic imaging.
Authors: Watson N A , Chalmers N , Naqvi N
Published: June 2014

We describe the case of an asymptomatic 24-year-old man with hypertension who was investigated for aortic coarctation but found on MR scanning to have narrowing of the distal thoracic aorta. Stenosis of the thoracolumbar aorta--the Middle Aorta Syndrome--is rare and is usually found below the diaphragm. The MRI and angiographic findings are presented.
Bronchial atresia associated with epibronchial right pulmonary artery and aberrant right middle lobe artery.
Authors: Ko S F , Lee T Y , Kao C L , Ng S H , Wan Y L , Lin J W , Chen W J
Published: June 2014

We report a case of bronchial atresia associated with an epibronchial right pulmonary artery (ERPA) and an aberrant right middle lobe artery (ARMLA). CT showed a branching opacity, which was hyperintense on MR images, in the anterior segment of the right upper lobe with segmental hyperinflation and the ERPA. At surgery, the ARMLA was found to originate from the ERPA, crossing the anterior aspect of the right upper lobe bronchus. It is postulated that the ARMLA might have interfered with the normal bronchial development, leading to the development of segmental bronchial atresia.
Familial osteoma of the cranial vault.
Authors: Ruggieri M , Pavone V , Polizzi A , Smilari P , Magro G , Merino M , Duray P H
Published: June 2014

A case of solitary osteoma of the parietal skull is described in a mother and her 12-year-old son. There were no other craniofacial or dysmorphic features and there was no history of previous cranial trauma or inflammatory process and no radiographic evidence of other skeletal lesions in both patients. Family history was otherwise unremarkable. Gardner syndrome was ruled out by excluding other associated clinical abnormalities and by family history. The clinical and radiological features of the patients' osteomas were different from those of Albright hereditary osteodystrophy, fibrodysplasia ossificans progressiva, progressive osseous heteroplasia and familial ectopic ossification. To the author's knowledge this is the first case of the familial presentation of osteomas.
Virtual cystoscopy based on helical CT scan datasets: perspectives and limitations.
Authors: Merkle E M , Wunderlich A , Aschoff A J , Rilinger N , Görich J , Bachor R , Gottfried H W , Sokiranski R , Fleiter T R , Brambs H J
Published: June 2014

The purpose of the study was to simulate cystoscopy based on three-dimensional helical CT scan datasets in real-time in patients with tumours of the urinary bladder. A helical CT scan with double detector technology was carried out pre-operatively in 11 patients with histologically confirmed carcinoma of the urinary bladder and one patient with chronic cystitis. A non-enhanced scan was first performed, followed by an examination in the early phase of contrast medium enhancement. Further images were acquired after adequate filling of the bladder with contrast medium, approximately 30 min after injection. These data were transferred to a separate graphic computer workstation and reconstructed. The results were then compared with the cystoscopic and histopathological findings. All tumours of the urinary bladder identified at fibreoptic cystoscopy were shown on virtual cystoscopy. The best reconstruction results were obtained from data acquired 30 min after injection of contrast medium. The ureteric orifices were not visualized at virtual cystoscopy. These data lead us to conclude that, at present, virtual cystoscopy has not reached the quality of fibreoptic examination and remains restricted to use in specific cases, for example patients with urethral strictures.
Three-dimensional spiral CT angiography in pancreatic surgical planning using non-tailored protocols: comparison with conventional angiography.
Authors: Blomley M J , Albrecht T , Williamson R C , Allison D J
Published: June 2014

The aim of this study was to investigate three-dimensional spiral computed tomography (3DCT) as an adjunct to routine pancreatic CT scanning, with particular regard to the identification of surgically important hepatic arterial anomalies, correlated with conventional visceral angiography. 32 patients underwent spiral CT scans prior to pancreatic surgery using established protocols. Oral contrast medium was used throughout. 150 ml of intravenous contrast medium was given at 3 ml s-1 with a 24 s spiral CT sequence starting 35 s after the start of infusion. Two protocols were employed, both with a pitch of 1:3 mm table feed/collimation (n = 17) and 5 mm table feed/collimation (n = 15). Overlapping (1 mm minimum) axial reformats were reconstructed. 3DCT shaded-surface displays of the visceral arteries were assessed for visceral arterial anomalies. Visceral angiography (n = 23) was independently correlated. Satisfactory 3D angiograms were performed in all but one patient, in whom the coeliac axis was missed. (i) 3 mm protocol: 3DCT (n = 17) showed three anomalous right hepatic arteries (ARHA), one trifurcation anomaly and one splenic artery with an aortic origin. Angiography (n = 11) confirmed these findings, although one patient with an ARHA did not have angiography. A left gastric arterial supply to the left liver was not detected. (ii) 5 mm protocol: 3DCT (n = 15) showed two cases of ARHA. While confirming these findings, angiography (n = 12) showed a third case of ARHA, in which the coeliac and superior mesenteric artery had very close origins. A left gastric supply to the left liver was also missed. It is concluded that satisfactory 3DCT is possible without changing existing scanning protocols, although narrow sections are required for the confident assessment of right hepatic arterial anomalies, and any left hepatic supply via the left gastric artery was poorly assessed in this series.
In vivo assessment of neovascularization of liver metastases using perfusion CT.
Authors: Miles K A , Leggett D A , Kelley B B , Hayball M P , Sinnatamby R , Bunce I
Published: June 2014

Neovascularization of tumours produces a high microvessel density. Although diagnostic imaging is unable to visualize microvessels directly, it is possible to demonstrate associated changes in tissue perfusion. The aim of this study was to use the quantitative functional information and high spatial resolution of perfusion computed tomography to study neovascularization of hepatic metastases. Perfusion CT was performed in 13 patients with hepatic metastases from various primary tumours. Arterial perfusion was measured in the metastasis; both arterial and portal perfusion were measured in a small rim of liver tissue immediately adjacent to the metastasis. Perfusion measurements were correlated against survival of the patient in nine cases. Arterial perfusion was increased above normal values, both in the metastasis (median: 0.62 ml min-1 ml-1; range: 0.26-3.05 ml min-1 ml-1) and in the adjacent liver (median: 0.51 ml min-1 ml-1; range: 0.14-1.60 ml min-1 ml-1). Portal perfusion of adjacent liver was highly variable (median: 0.30 ml min-1 ml-1; range: 0.05-1.85 ml min-1 ml-1). Arterial perfusion was positively correlated with portal perfusion within liver tissue adjacent to metastases (p < 0.05, r = 0.58), a reversal of the normal situation. Survival of the patient correlated with arterial perfusion within the metastasis (p < 0.05, r = 0.69) but more closely with arterial perfusion in the adjacent liver (p < 0.02, r = 0.78). In conclusion, alterations in perfusion within metastases and adjacent liver are in accordance with the histological features of neovascularization. Perfusion CT offers a method for studying neovascularization in the living patient and offers prognostic information.
Studies of acoustic streaming in biological fluids with an ultrasound Doppler technique.
Authors: Zauhar G , Starritt H C , Duck F A
Published: June 2014

Acoustic streaming generated by diagnostic ultrasound fields is an important area for study both for safety reasons and because of its potential application as a diagnostic tool. A method of investigating streaming in biological fluids is reported. A number of fluids were insonated using a 3.5 MHz weakly focused single element transducer which was driven in pulsed mode. Streaming was detected in each fluid using an 8 MHz continuous wave Doppler system. The maximum streaming velocity was obtained by spectral analysis of the Doppler signal. Using this system longitudinal streaming profiles were measured. At an acoustic power of 150 mW the maximum streaming velocities detected were: 9.3 cm s-1 in water, 6.8 cm s-1 in 4.5% human serum albumin (HSA) solution and 4.9 cm s-1 in blood, when transmission was through a water path of approximately 10 cm into a 3 cm sample of fluid. When measurements were made in the biological fluids alone, without a water path, the maximum streaming velocities were reduced.
The secondary radiation grid; its effect on fluoroscopic dose-area product during barium enema examinations.
Authors: Lloyd P , Lowe D , Harty D S , Eyes B
Published: June 2014

The secondary radiation grid is placed between the patient and the image intensifying screen, during fluoroscopy, to attenuate the incident forward scattered radiation. This reduction in scatter improves the radiographic contrast and hence image quality. However, this improved quality is achieved at the expense of greater radiation exposure to the patient, as this higher exposure is required to produce satisfactory image density. Patients scheduled to have a barium enema were randomly allocated into two groups. One group had the procedure performed with the grid in situ throughout the procedure. The second group was examined with the grid removed for fluoroscopy but returned for image acquisition. The fluoroscopic dose-area product (DAP) was recorded for both groups using a dose-area product meter. The DAP was not recorded for spot film acquisition. The results suggest that there is approximately a 50% reduction in DAP to the second group. We can be 95% certain that, on average, the ratio of doses in patients without the grid in situ to those screened with the grid is between 0.40 and 0.58, with the best estimate being 0.48. Multiple regression methods to take account of the effects of weight, sex and time, revised this estimate as 0.57, with 95% confidence interval from 0.52 to 0.63. Sex, weight and exposure time accounted for 61% of variation in dose-area products, with time alone accounting for 41%. Grid status accounted for another 22% of variation, which represents over a half of the remaining variation once sex, weight and exposure time have been allowed for. We therefore recommend that the routine use of an antiscatter grid during fluoroscopy should be abandoned. The use of a grid should be restricted to those patients (usually obese) when poor visualization is obtained in its absence.
The effects of radioactive iodine in thyroid remnant ablation and treatment of well differentiated thyroid carcinoma.
Authors: Lin J D , Kao P F , Chao T C
Published: June 2014

Although the use of radioactive iodine (131I) in the treatment of thyroid cancer is well established, treatment dose is not well standardized. In order to deduce the appropriate dose for thyroid remnant ablation and the effect of 131I in the treatment of distant metastases, data for 544 patients with papillary or follicular thyroid cancer were retrospectively reviewed. All patients received surgical treatment followed by post-operative 131I. If remnants were present in the 0.2 GBq 131I diagnostic scan, 1.1-3.7 GBq 131I were administered for ablation. For the treatment of distant metastases 3.7-5.6 GBq were used. Of 318 patients receiving 131I for thyroid remnant ablation, 290 were successfully ablated. After one dose of 1.1 GBq 131I, 82% (159/194) of thyroid remnants were ablated. During the follow-up period, two of 14 Stage IV patients with lung or mediastinal metastases at the time of operation achieved complete clinical remission. Factors identified as influencing response to 131I therapy included age, clinical stage, survival, recurrence, extent of surgery and the 1 month post-operative serum thyroglobulin (Tg) level. In conclusion 1.1 GBq 131I was adequate for thyroid remnant ablation unless distant metastases were present. Radioactive 131I has a role in the treatment of well differentiated thyroid carcinoma with pulmonary metastases but seems to be less effective for treatment of bone metastases.
The ultrasound appearances of intratesticular varicocoele.
Authors: O'Donnell P G , Dewbury K C
Published: June 2014

Extratesticular varicocoele is a common clinical finding, with well recognized sonographic appearances. We report the ultrasound findings in a patient with intratesticular varicocoele (ITV), an extremely rare entity, which was an incidental finding during scrotal sonography. There are differences in both the imaging findings and clinical presentation from previously reported cases. The history of undescended testis and subsequent orchidopexy in our patient contribute to the aetiology of the ITV.
Cervical ecchordosis physaliphora: CT and MR features.
Authors: Ng S H , Ko S F , Wan Y L , Tang L M , Ho Y S
Published: June 2014

We report a case of cervical ecchordosis physaliphora in an elderly man who presented with hemihypoaesthesia and contralateral hemiparesis. MRI showed a well defined, non-enhancing extradural mass lesion on the dorsal surface of the odontoid process of the axis. The lesion was of intermediate signal intensity on T1 weighted images and of low signal intensity on T2 weighted images. CT showed a small bony defect on the adjacent cortex of the odontoid process. Recognition of the imaging features of ecchordosis physaliphora is helpful in suggesting the diagnosis and differentiating the lesion from chordoma.
Contrast media-induced nephrotoxicity--questions and answers.
Authors: Morcos S K
Published: June 2014

The intravascular administration of contrast media (CM) can produce acute haemodynamic changes in the kidney characterized by an increase in renal vascular resistance and a decrease in the glomerular filtration rate (GFR). These changes may lead to clinically significant reduction in renal function in patients with pre-existing risk factors such as diabetic nephropathy, congestive heart failure and dehydration. The pathophysiology of the renal haemodynamic effects of CM involves activation of the tubuloglomerular feedback (TGF) mechanism and the modulation of the intrarenal production of vasoactive mediators such as prostaglandins, nitric oxide, endothelin and adenosine. The TGF response is osmolality-dependent and accounts for about 50% of the acute functional effects of high osmolar CM on the kidney. Reduction in the synthesis of the endogenous vasodilators nitric oxide and prostaglandins increases the nephrotoxicity of CM. Endothelin and adenosine play a crucial role in mediating the acute functional effects of CM. Antagonists of these mediators attenuate the reduction in renal function induced by contrast agents. Vacuolization of the cells of the proximal tubules and necrosis of those of the medullary ascending limbs of loops of Henle are the main structural effects of CM in the kidney. The reduction in renal function induced by CM could be minimized by the use of low osmolar CM and adequate hydration. The prophylactic administration of calcium channel blockers and adenosine antagonists such as theophylline may also offer some protective effect.
An economic evaluation of the use of rare earth screens to reduce the radiation dose from diagnostic X-ray procedures in Israel.
Authors: Ginsberg G M , Schlesinger T , Ben-Shlomo A , Kushilevsky A , Margaliot M , Oren M , Finkleman M , Friedman A , Handlesman M , Lev B
Published: June 2014

In Israel the diffusion of rare earth screen technology has been limited. These screens could halve the radiation dose to the patient from diagnostic X-ray radiography, with little managerial effort and without being detrimental to the quality of the diagnostic image. We estimated the total effective dose from diagnostic film radiography capable of reduction by the use of rare earth screens, based on the number of hospital and ambulatory diagnostic X-ray procedures. This number was multiplied by the computed radiation dose per body site for a series of diagnostic procedures. The annual dose was approximately 0.53 mSv per head, approximately half of which could be averted by the introduction of rare earth screen technology. Based on a fatality risk of 3% Sv-1, it is estimated that the adoption of rare earth screen technology might reduce the annual incidence of cancer by some 93 cases, half of which would be fatal after an average latency period of 18.4 years. The cost of purchasing rare earth screens on a nationwide basis is approximately $3.0 million. This cost is outweighed by a saving of $9.6 million in X-ray tube replacement costs over the period 1997-2006. Government legislation enforcing the use of rare earth screens is essential, because of the lack of prestige associated with acquiring rare earth technology, as well as institutional reluctance to accept the external benefits of reduced morbidity and mortality and/or to extend budgetary time horizons.
An image registration scheme applied to verification of radiation therapy.
Authors: Leszczynski K W , Loose S , Boyko S
Published: June 2014

The introduction of modern conformal radiation therapy techniques requires high geometric precision in treatment delivery which must be verified. For that purpose we have developed an automated system based on registration of portal and simulation (or planning) image pairs. The image registration is performed on anatomical features which are automatically extracted from the portal image. The portal image is then registered with a planning or simulation radiographic image which represents the geometric prescription for the treatment, using an optimized version of the chamfer matching algorithm. Subsequently, the magnitude of the radiation field displacement during treatment is measured by registering the prescribed and treated field boundaries. Algorithms based on chamfer matching and polygon matching have been used for the field boundary registration. Performance of the entire scheme was evaluated on a series of 15 portal images of a pelvic phantom representing various known degrees of the radiation field displacement. The measurements of the radiation field displacements performed by the automated system proved very reliable and after correction for systematic bias agreed to within 1.5 mm or 1 degree with the displacements applied. Second test series involved comparisons between the automated registrations and those performed manually/visually by an experienced human observer, on 31 portal images acquired during treatments of 18 pelvic patients. These tests showed close agreement (in 80% of cases discrepancies were smaller than 1.5 mm or 1.5 degrees) between the automated scheme and the human observer. It is concluded that the developed scheme would be suitable for online geometric verification of radiation therapy treatments.
Enhancement of radiosensitivity of rat rhabdomyosarcoma R1H with normobaric carbogen and hyperbaric oxygen (HBO) using conventionally fractionated irradiation.
Authors: Hartmann K A , Carl U M , Plugge D C , Schneider C J , Sminia P
Published: June 2014

Hypoxic clonogenic cells are an important contributory factor in tumour radioresistance. The objective of the present study was to evaluate whether hyperbaric oxygen enhances tumour radiosensitivity, using a conventionally fractionated irradiation schedule, and whether the radiosensitizing potential is different from carbogen. Experiments were performed using the rhabdomyosarcoma R1H model transplanted subcutaneously in the flank of WAG/Rij rats. A total of 30 X-ray fractions of 2 Gy were given either in air, normobaric carbogen or high pressure oxygen (HPO) (240 kPa, 2.37 atm) without anaesthesia. The time taken to achieve complete remission was 38.7 +/- 3.6 days, 36.7 +/- 2.7 days and 32.4 +/- 4.1 days for air, normobaric carbogen and HBO, respectively. The differences between air and HBO (p = 0.002) and carbogen and HBO (p = 0.015) were significant. Use of carbogen and HBO produced the same local control probability at 150 days and this was significantly higher than local control under ambient conditions (p < 0.0001). It was concluded that the time to achieve complete remission of the rat rhabdomyosarcoma R1H can be shortened by HBO. Furthermore, both HBO and carbogen give higher local control probabilities than treatment under ambient conditions when used with a conventionally fractionated radiation schedule.
Middle cranial fossa arachnoid cysts: not always a benign entity.
Authors: Callaway M P , Renowden S A , Lewis T T , Bradshaw J , Malcolm G , Coakham H
Published: June 2014

Arachnoid cysts are often discovered as incidental findings on cranial imaging. A rare manifestation is described in a child presenting acutely with symptoms and signs of raised intracranial pressure.
The vanishing heart--deterioration on chest radiography with clinical improvement during prone position ventilation.
Authors: van der Werf T S , Wolf R F , Tulleken J E , Ligtenberg J J , Zijlstra J G
Published: June 2014

Prone position ventilation is used in the treatment of ARDS. Its beneficial effects are due to increased ventilation of the dorsal lung areas. Consequently, the now dependent parts of the lungs collapse, resulting in decreased sharpness of the cardiac silhouette. The latter may be misinterpreted as a worsening of the cardiopulmonary condition while, in fact, gas exchange and ventilation may be markedly improved. These features are illustrated in the case presented.
Outpatient angiography: a prospective study of 3 French catheters in unselected patients.
Authors: Fitzgerald J , Andrew H , Conway B , Hackett S , Chalmers N
Published: June 2014

Financial constraints and bed shortages led to a re-evaluation of the policy of routine hospital admission for angiography. All patients referred for peripheral and renal angiography over an 8 month period had the procedure performed as an outpatient with a 3 F catheter. Patients were kept supine for 1 h and discharged 2 h after the angiogram. No significant complications resulted from the early mobilization of 219 patients who had outpatient 3 F angiography. It was a safe, well tolerated procedure, resulting in images of consistently adequate quality.
Lumbar spine magnetic resonance imaging: comparison between fast spin echo proton density and spin echo T1 axial scans.
Authors: Peh W C , Siu T H , Chan J H , Chan F L
Published: June 2014

Spin echo (SE) T1 axial scans are routinely obtained in magnetic resonance imaging of the lumbar spine in many centres. This study directly compared matched SE T1 and fast SE (FSE) proton density (PD) axial scans. Both SE T1 and FSE PD axial scans of the lumbar spine were obtained in 116 consecutive patients. The imaging parameters (field-of-view, slice thickness, interslice gap, number of excitations and matrix size) and scan levels were identical for each pair of sequences. At two selected levels, L4/5 and L5/S1, various structures were independently graded by two observers. In 232 lumbar levels analysed, the bone marrow, epidural fat, disc, extradural nerve root and facet joint were equally well seen on both sequences by both observers (combined mean grades of 2.93-2.99). The thecal sac was marginally better depicted on FSE PD than on SE T1 images, with mean grades of 2.96 and 2.88, respectively. The psoas muscle was adequately visualized for diagnostic purposes on both sequences (mean grades of 2.30-2.32). The cauda equina were better seen on FSE PD (mean grade 1.92) than on SE T1 (mean grade 1.00) images. In conclusion, FSE PD scans are comparable to and may potentially replace SE T1 axial MR scans of the lumbar spine.
Diagnosis and staging of pancreatic cancer by endoscopic ultrasound.
Authors: Akahoshi K , Chijiiwa Y , Nakano I , Nawata H , Ogawa Y , Tanaka M , Nagai E , Tsuneyoshi M
Published: June 2014

The aim of this study was to evaluate the usefulness of and problems associated with endoscopic ultrasonography (EUS) in the diagnosis and pre-operative staging of pancreatic cancer. 96 patients suspected of having pancreatic cancer were pre-operatively examined with EUS. 37 of these 96 patients had pancreatic cancer. Results of the EUS imaging were compared with findings of histology and/or surgery, and the patient's clinical course. The sensitivity and specificity of EUS for diagnosing pancreatic cancer were 89% and 97%, respectively. EUS had excellent sensitivity regardless of tumour size or location. EUS was accurate (90%) in determining tumour size in pancreatic cancers less than 3 cm in maximum diameter, but not for tumours greater than 3 cm (30%). The accuracy of tumour (T) and nodal (N) staging were 64% and 50%, respectively. EUS is a promising method for the early diagnosis and pre-operative staging of pancreatic cancers, but requires further refinement.
A pilot survey of radiation doses received in the United Kingdom Breast Screening Programme.
Authors: Burch A , Goodman D A
Published: June 2014

A survey of radiation dose and compressed breast thickness was conducted in samples of women undergoing mammography in the United Kingdom National Health Service breast screening programme. The aims were to determine the average value and distribution of dose and thickness, and to identify technical difficulties in carrying out such a survey. Values of breast thickness and mean glandular dose, calculated from exposure factors and measured X-ray beam parameters, were collected for 4633 women in 92 screening units in 1994 and 1995. The median (lower quartile, upper quartile) dose per film was 1.7 (1.2, 2.4) mGy for the mediolateral oblique view (mean thickness 57 mm) and 1.4 (1.1, 2.0) mGy for the craniocaudal view (mean thickness 52 mm). The median dose per woman was 1.8 (1.3, 2.5) mGy for a one-view examination and 3.3 (2.3, 4.6) mGy for a two-view examination. The dose per film showed an exponential relationship to breast thickness, but no relationship was found between median dose and median breast thickness in the different screening units, possibly because of errors in breast thickness measurement. The values of breast thickness and dose were generally consistent with those in other published surveys, allowing for differences in radiographic technique. No relationship between breast dose and standard optical density was demonstrated. Some recommendations for the conduct of future surveys of breast dose in the UK are proposed.
Storage phosphor direct magnification mammography in comparison with conventional screen-film mammography--a phantom study.
Authors: Funke M , Breiter N , Hermann K P , Oestmann J W , Grabbe E
Published: June 2014

Contact mammography with current photostimulable storage phosphors is hampered by its low spatial resolution. Detail visualization can be improved by geometric magnification radiography which enlarges small details to exceed inherent image noise. This study compares storage phosphor mammography using a dedicated direct magnification system with state-of-the-art conventional screen-film mammography. Storage phosphor direct magnification survey views (1.7x) and spot views (4x) were obtained with a prototype mammography unit providing focal spot sizes of 120-40 microns. Conventional technique screen-film survey views (1.1x) and spot views (1.8x) served as comparison. A contrast detail study and a receiver operating characteristic (ROC) analysis using an anthropomorphic breast phantom with superimposed microcalcifications was performed. Contrast detail resolution in the digital and conventional survey views were equivalent. For the spot views, contrast detail resolution was significantly higher with the digital technique (p < 0.001). ROC analysis of 400 observations demonstrated a significantly higher performance (p < 0.001) with digital images versus conventional screen-film mammograms. The area under the ROC curve (Az) in the digital survey views was 0.76 +/- 0.07 versus 0.59 +/- 0.02 in the conventional technique. In digital spot views, Az was 0.82 +/- 0.07 as compared with 0.66 +/- 0.04 in the conventional spot views. These results suggest that storage phosphor digital mammography in conjunction with direct geometric magnification technique may be superior to conventional screen-film mammography in the detection of microcalcifications.
A pilot study on concurrent platinum chemotherapy and intracavitary brachytherapy for locally advanced cancer of the uterine cervix.
Authors: Koumantakis E , Haralambakis Z , Koukourakis M , Mazonakis M , Haldeopoulos D , Papageorgiou N , Livas V , Froudarakis G , Varveris H
Published: June 2014

This study aims to evaluate the feasibility, toxicity and efficacy of concurrent chemotherapy with platinum compounds and brachytherapy, for locally advanced carcinoma of the cervix (Stages IIA/B, IIIA). The hypothesis was that synchronous chemo-brachytherapy may be sufficient to cause down-staging of the tumour, to render it operable, and hopefully improve the prognosis. 36 women with locally advanced cervical cancer were treated with concomitant brachytherapy and chemotherapy before surgery and/or definitive external radiotherapy. All patients received two caesium-137 Selectron MDR applications, 1 week apart. The dose calculated to point A for each implant was 20-25 Gy. Chemotherapy consisting of continuous cisplatin infusion (50 mg m2) and of carboplatin (300 mg m-2) was given simultaneously with intracavitary irradiation during the first and second application, respectively. The combined therapy was followed when feasible by radical hysterectomy, pelvic lymphadenectomy and pelvic radiotherapy. Patients deemed ineligible for surgery because of poor response were given full dose external radiotherapy. 31/36 patients were treated by Wertheim hysterectomy of whom 10 had negative lymph nodes and resection margins. Definitive external radiotherapy was given in the remaining five patients. Overall, 83% were disease free at 2.8 years mean follow-up. The most frequent acute side-effects of chemobrachytherapy were nausea and vomiting. No renal toxicity was observed. Thrombocytopenia was seen in five patients and was responsible for delayed surgery in four patients. Concerning late effects, two patients developed grade 2 intestinal sequelae, two mild frequency and two vaginal stenosis. One rectovaginal and one vesicovaginal fistula developed in two patients; and a third patient had a fistula associated with tumour recurrence. Concurrent brachytherapy and chemotherapy with platinum compounds is well tolerated and effective in reducing tumour bulk before definitive local treatment (surgery or external radiotherapy), in patients with locally advanced carcinoma of the uterine cervix.
Target volume definition for three-dimensional conformal radiation therapy of lung cancer.
Authors: Armstrong J G
Published: June 2014

Three-dimensional conformal radiation therapy (3DCRT) is a mode of high precision radiotherapy which has the potential to improve the therapeutic ratio of radiation therapy for locally advanced non-small cell lung cancer. The preliminary clinical experience with 3DCRT has been promising and justifies further endeavour to refine its clinical application and ultimately test its role in randomized trials. There are several steps to be taken before 3DCRT evolves into an effective single modality for the treatment of lung cancer and before it is effectively integrated with chemotherapy. This article addresses core issues in the process of target volume definition for the application of 3DCRT technology to lung cancer. The International Commission on Radiation Units and Measurements Report no. 50 definitions of target volumes are used to identify the factors influencing target volumes in lung cancer. The rationale for applying 3DCRT to lung cancer is based on the frequency of failure to eradicate gross tumour with conventional approaches. It may therefore be appropriate to ignore subclinical or microscopic extensions when designing a clinical target volume, thereby restricting target volume size and allowing dose escalation. When the clinical target volume is expanded to a planning target volume, an optimized margin would result in homogeneous irradiation to the highest dose feasible within normal tissue constraints. To arrive at such optimized margins, multiple factors, including data acquisition, data transfer, patient movement, treatment reproducibility, and internal organ and target volume motion, must be considered. These factors may vary significantly depending on technology and techniques, and published quantitative analyses are no substitute for meticulous attention to detail and audit of performance.
Ultrasound and Doppler features of accessory spleens and splenic grafts.
Authors: Bertolotto M , Gioulis E , Ricci C , Turoldo A , Convertino C
Published: June 2014

16 splenic grafts and 24 accessory spleens were evaluated with ultrasound, colour Doppler and power Doppler imaging, in order to compare the features of splenic grafts and accessory spleens. 12 splenic grafts (11 surgically implanted, 1 islet of splenosis) were detected in eight patients following splenectomy 6-12 months previously. Four of the surgically implanted splenic grafts were found in three patients following splenectomy 16-18 days previously. 21 accessory spleens were incidentally detected in 20 subjects who had not been operated upon, whereas three enlarged accessory spleens were found in 10 patients who underwent splenectomy 6-12 months previously. The size, shape, rim features, echogenicity, acoustic enhancement and vascularization of the splenic grafts and accessory spleens were evaluated. The splenic grafts were oval with lobulated margins, an inhomogeneous pattern in 36% and acoustic enhancement in 64%. Multiple feeding vessels arising from the surrounding tissue entered the periphery of 10 splenic grafts in the eight patients operated on 6-12 months previously, whereas no vascular signals were detected in the four splenic grafts of the three patients operated on 16-18 days ago. Accessory spleens were round with smooth echogenic margins and a vascular hilum arising from the splenic vessels. In conclusion colour Doppler and power Doppler allow differentiation between accessory spleens and splenic grafts basing on their shape and vascular supply.
Evaluation of cystic ovarian lesions using apparent diffusion coefficient calculated from turboFLASH MR images.
Authors: Moteki T , Ishizaka H
Published: June 2014

Serial turboFLASH (fast low-angle shot) images with and without diffusion-perfusion (DP) gradients were used to evaluate the contents of cystic ovarian lesions. 19 ovarian cysts seven serous cystadenomas, six mucinous cystadenomas and 13 malignant cystic ovarian tumours were studied. T1 and T2 weighted spin echo images, serial turboFLASH images with and without DP gradients (b = 295.1 and 0 s mm-2, respectively) were obtained. Using these images, the apparent diffusion coefficients (ADCs) were calculated within the cystic contents of these lesions. Approximately corrected ADC (ADC') values were also calculated in order to reduce T1 contamination from ADCs, using results of a phantom study. Ovarian cysts and serous cystadenomas showed larger ADC and ADC' values than the cystic contents of malignant ovarian lesions (p < 0.01). Mucinous cystadenomas show no distinct ADC difference to any other group of cases. However, if the highest ADC' loculus was selected as being representative, mucinous cystadenomas showed a larger ADC' value than malignant cystic neoplasms (p < 0.03). In conclusion, diffusion-weighted MRI is possibly of use in evaluating cystic contents of ovarian lesions.
Radio-opaque markers for stereotactic imaging of uveal melanoma.
Authors: Zehetmayer M , Schima W , Menapace R , Kitz K , Radner W , Dieckmann K
Published: June 2014

In in vitro and in vivo studies, episclerally sutured radio-opaque markers were evaluated as localizers for better determination of the clinical tumour volume prior to stereotactic radio-therapy of uveal melanoma. Four different types of markers were studied in vitro: tantalum marker, 2.5 mm in diameter; ring-shaped markers custom-designed in polymethyl methacrylate (PMMA), 2.6 mm and 3.0 mm in diameter; and barium-impregnated silicone rubber spheres, 2 mm in diameter. In vivo PMMA markers 3.0 mm in diameter and barium-impregnated silicone rubber spheres 2 mm in diameter were used. The best results were obtained with the barium-impregnated silicone rubber spheres both in vitro and in vivo. For the CT-delineation of selected uveal melanomas with either a flat discoid shape or flat tumour extensions or when adjacent serous retinal detachment is present, small episclerally sutured barium-impregnated silicone rubber spheres are useful as localizers for determining the clinical tumour volume.
Estimation of compressed breast thickness during mammography.
Authors: Highnam R P , Brady J M , Shepstone B J
Published: June 2014

To estimate radiation dose during mammography the breast thickness must be known. We present a new method for estimating the thickness of a compressed breast using only the breast image as projected onto a mammogram, calibration data such as the mAs value and image processing techniques. The method proves to be of high accuracy (+/- 0.2 cm for craniocaudal mammograms) and has the advantage over other methods of allowing retrospective estimation of thickness.
Patient and staff radiation dose in fluoroscopy-guided TIPS procedures and dose reduction, using dedicated fluoroscopy exposure settings.
Authors: Zweers D , Geleijns J , Aarts N J , Hardam L J , Laméris J S , Schultz F W , Schultze Kool L J
Published: June 2014

Fluoroscopy guided interventions, such as transjugular intrahepatic portosystemic shunt (TIPS) procedures, can results in relatively high radiation doses to patients and staff. The purpose of this study was to evaluate the possible benefit of dedicated fluoroscopy exposure factors in the reduction of doses. Doses to patients and staff were measured during fluoroscopy-guided TIPS procedures in two Dutch university hospitals. Patient doses were calculated from dose-area product (DAP) measurements, entrance beam dimensions and DAP conversion factors. Staff doses were measured outside lead aprons using electronic personal dosemeters. Average patient entrance skin dose (ESD) rate during fluoroscopy was 49 mGy min-1 (13 cases, average fluoroscopy duration 32 min) in one hospital, and 6 mGy min-1 (10 cases, average fluoroscopy duration 50 min) in the other. Estimated staff effective dose per procedure was 28 microSv average in the first hospital compared with 4 microSv average in the other. The use of dedicated fluoroscopy exposure factors, with a relatively high tube voltage and lower tube current resulted in a significant dose reduction for patient and staff in this type of radiological intervention.
Benign solitary fibrous tumour of the pre-sacral space: MRI findings.
Authors: Chun H J , Byun J Y , Jung S E , Kim K H , Shinn K S
Published: June 2014

Benign solitary fibrous tumour, a rare mesenchymal tumour of adults, usually arises from the pleura. Only a few cases have been reported in the retroperitoneum and, to our knowledge, there has been no report of its imaging features. We describe the MRI features of benign solitary fibrous tumour arising from the pre-sacral space.
Tuberculous pericarditis: MRI features with contrast enhancement.
Authors: Hayashi H , Kawamata H , Machida M , Kumazaki T
Published: June 2014

Tuberculous pericarditis has decreased in incidence, but early diagnosis and treatment are critical because constrictive pericarditis is a serious complication of this condition. The appearances of tuberculous pericarditis on gadolinium enhanced magnetic resonance imaging are described and the value of this modality in achieving an early diagnosis is emphasized.
Mucinous biliary cystadenocarcinoma containing gas bubbles secondary to duodenal invasion.
Authors: Stacher R , Szolar D H , Bacher H , Preidler K W
Published: June 2014

Biliary cystadenocarcinoma is a rare, usually intrahepatic neoplasm. A case is described in which an intrahepatic cystadenocarcinoma invaded the duodenum. This resulted in intratumoral gas.
Enhancement of subtle density differences of the lung parenchyma on CT.
Authors: Yang G Z , Chabat F , Hansell D M
Published: June 2014

Several pulmonary conditions are characterized by the finding of areas of decreased attenuation relative to adjacent normal lung parenchyma on computed tomography. In particular, the identification of areas of the lung affected by small airways disease is difficult as the reduction in lung density is subtle and the regions are poorly marginated. This paper presents a novel wavelet analysis technique which increases the conspicuity of differences between normal and abnormal lung parenchyma.
A comparison of patient dose for examinations of the upper gastrointestinal tract at 11 conventional and digital X-ray units in The Netherlands.
Authors: Geleijns J , Broerse J J , Chandie Shaw M P , Schultz F W , Teeuwisse W , Van Unnik J G , Zoetelief J
Published: June 2014

The objective of this study was to derive the effective dose to patients from examinations of the upper gastrointestinal (GI) tract at 11 X-ray units in 10 Dutch hospitals. Entrance dose and entrance dose rate were measured at the surface of a homogeneous PMMA phantom and at the entrance surface of the image intensifier. Dose-area products (DAPs) were assessed during examinations of patients. The patients (334 females and 256 males) ages were 18-95 years (average 52 years). Effective dose was assessed from DAP using Monte Carlo computer calculations for male and female mathematical anthropomorphic phantoms. The DAPs measured during the survey showed substantial variations, i.e. an overall average value of 21 Gy cm2 and a range of average DAP per X-ray unit varying from 7 to 56 Gy cm2. Variations in the number of images (8-28) and the fluoroscopy time (1.7 min-7.0 min) were also large. A DAP to effective dose conversion factor of 0.32 mSv Gy cm-2 was derived for upper GI studies. The dose survey yielded an overall average effective dose of 6.7 mSv. At one location an examination involving as many as 28 projections was performed, whilst maintaining a DAP well below 15 Gy cm2 and an effective dose below 6 mSv. This was achieved using modern equipment (i.e. high frequency generator, digital spot films) with 0.2 mm additional copper filtration and a relatively high tube voltage. For examinations of the upper GI tract, the application of a reference value of 30 Gy cm2 for the DAP will ensure that, in general, the effective dose to individual patients will not exceed 15 mSv.
The value of colour Doppler ultrasonography for small bowel involvement of adult Henoch-Schönlein purpura.
Authors: Shirahama M , Umeno Y , Tomimasu R , Dohmen K , Miyamoto Y , Shimoda Y , Irie K , Ishibashi H
Published: June 2014

Three patients presented with a non-thrombocytopenic purpuric rash on their upper and lower limbs, abdominal pain, diarrhoea, and arthralgia. Grey scale ultrasound showed abnormally thickened walls of the small bowel. Colour Doppler showed blood flow signals in the diseased bowel wall in all patients. Subsequent barium and endoscopic studies showed oedematous bowel loops with petechial lesions. Biopsy from the purpuric rash of the skin demonstrated vasculitis of subdermal small vessels. The clinical diagnosis of Henoch-Schönlein purpura was made in each case. This paper describes the efficacy of grey scale and colour Doppler ultrasonography in the assessment of the small bowel involvement of Henoch-Schönlein purpura.