bluuebunny/crossref_metadata_2025 huggingface dataset:
Dual X-ray absorptiometry of the lumbar spine: the precision of paired anteroposterior/lateral studies
Authors: Blake G M , Jagathesan T , Herd R J M , Fogelman I
Published: July 2009

Supine lateral dual X-ray absorptiometry (DXA) has the potential to provide a sensitive and precise method of measuring changes in trabecular bone mass in the lumbar vertebral bodies. An important reason for the improvement in precision compared with the earlier decubitus lateral technique is the use of baseline compensation, an algorithm which computes the changes in lateral bone mineral density (BMD) using data from both anteroposterior (AP) and lateral scans. This report examines the precision of supine lateral DXA based on scans of 12 female volunteers (age range 21–56 years). Five AP/lateral scan pairs were performed on each subject and precision expressed by the coefficient of variation (CV). For the AP scan the CV for both L1–L4 and L2–L4 BMD was 0.8%. Precision of the L2–L4 lateral vertebral body, mid-vertebral and volumetric BMD parameters with (without) the baseline compensation correction were 1.2% (2.1%), 2.4% (3.0%) and 1.5% (2.5%), respectively. Two methods of performing baseline compensation, referred to as the multiplicative and additive algorithms, were compared and the former shown to give significantly better precision. The precisions of different combinations of lumbar vertebrae for the measurement of lateral vertebral body BMD were compared and the precision for L2–L4 shown to be significantly better than for L3–L4. When individual vertebrae were examined L3 had the best precision although the differences with L2 and L4 were not significant. The study confirmed that supine lateral measurements of vertebral body BMD with baseline compensation give better precision than the decubitus method. The improvement makes it feasible to follow patients longitudinally and may allow the sensitivity of the lateral scan to supersede that of AP measurements.
Effect of tumour shrinkage on the biological effectiveness of permanent brachytherapy implants
Authors: Dale R G , Jones B , Coles I P
Published: July 2009

A tumour shrinkage factor is incorporated into previously derived linear-quadratic (LQ) formulae which allowed radiobiological assessment of the efficacy of permanently implanted radionuclides. The new formulations relate the biologically effective dose (BED) to radionuclide half-life, recovery half-life, tumour radiosensitivity, potential doubling time and linear shrinkage rate. Specific attention has been given to the following radionuclides: gold-198 (half-life, 2.7 days), palladium-103 (half-life, 17 days), ytterbium-169 (halflife, 32 days) and iodine-125 (half-life, 60 days). For each nuclide the log cell kill resulting from typically prescribed doses was calculated for a range of tumour clonogen doubling times at various radiosensitivities and linear shrinkage rates. It is shown that even relatively modest shrinkage rates are capable of enhancing the clinical potential of the longer-lived nuclides. However, even though the effect of tumour shrinkage is minimal in the case of gold-198, for fast growing and/or insensitive tumours there are fewer radiobiological uncertainties associated with the use of this nuclide. The revised equations may also have applications in certain types of biologically targeted radiotherapy.
An audit of a radiographer based ultrasound service
Authors: Weston M J , Morse A , Slack N F
Published: July 2009

A general ultrasound service has evolved over several years. Radiographers undertake the general ultrasound lists, and show the request card and the hard copy films to a radiologist prior to the patient leaving the department. Whilst it is generally accepted for radiographers to carry the burden of obstetric scanning, this is less so for general work. This audit is of a sample of 100 patients out of the general ultrasound lists. These patients underwent the standard service examination by a radiographer and subsequent report by the radiologist. They also had a separate examination and report by an independent radiologist. 42 patients were agreed to have normal findings. 75 diagnoses or observations were made in the remaining 58 patients. Discrepancies arose between the two limbs of the audit in 20 of the observations. Review of the hard copy films and repeat scanning of patients where necessary identified one relevant error by the auditing radiologist and three relevant errors by the standard service. Whilst errors are made both by radiologists and radiographers, it is concluded that the existing radiographer based ultrasound service provides a satisfactory level of accuracy.
Techniques for the assessment of the imaging characteristics of intravascular ultrasound scanners
Authors: Hoskins P R , McDicken W N
Published: July 2009

A Methods of assessing the imaging characteristics of intravascular ultrasound systems are described and applied to an HP Sonos 3000 system imaging at 12, 20 and 30 MHz. The presence of geometrical image distortion associated with bending of the catheter was detected by imaging silk filaments positioned at 45° around a circle. Distortion was clearly present indicating that it is likely to occur in clinical studies. Resolution measurements (–12 dB) were made from images of 30 μm Nylon. The axial resolution did not change with depth and was in the range 150–400 μm. The lateral resolution increased linearly with depth for all frequencies, with values in the range 0.9–1.7 mm at a depth of 5 mm. High frequency catheter transducers therefore generate ultrasound with beamshapes similar to those expected from the familiar performance of devices in the 2–10 MHz range. Penetration measurements were made with material known to be tissue equivalent at 3–7 MHz. The penetration depth varied from 4.5 to 14 mm depending on catheter and frequency. There is a need for the manufacture of tissue equivalent materials for use in the frequency range 20–30 MHz, and also for the design of phantoms based on these materials for the measurement of contrastdetail performance and penetration depth.
Vertebral measurements for assessment of osteoporosis
Authors: ITO M , Hayashi K , Yamada M , Nakamura T
Published: July 2009

We measured the vertebral heights and spinal bone mineral density (BMD) of healthy women, and morphometrically evaluated the physiological features of the vertebrae to investigate the relationship of BMD to types of spinal deformity as well as the radiographic detection rate for decreased vertebral bone density. Vertebral BMD was measured from LI to L4 using dual X-ray absorptiometry and from LI to L3 using quantitative computed tomography in 245 healthy women ranging in age from 22 to 81 years. The vertebral heights, anterior (Ha), middle (Hm), and posterior (Hp), were measured from T12 through L5, and the Ha/Hp and Hm/Hp ratios were calculated. Although the age-related reduction of vertebral height was not as marked as that of BMD, the vertebral heights, especially the Ha and Hm from T12 to L5 vertebrae, and the Ha/Hp and Hm/Hp from T12 to L3, significantly decreased with age. The presence of a wedge-shaped deformity was strongly related to cortical BMD, and biconcave deformity to trabecular BMD. Although investigation of the sensitivity and specificity of several criteria revealed that vertebra-specific dimension criteria are useful in the detection of decreased bone density, the detection of decreased BMD using vertebral measurements is considered to be limited.
A simple method for skin/lesion localization using magnetic resonance imaging
Authors: English P T , Dougal C , Griffiths P D , Gholkar A
Published: July 2009

We have made a series of gadolinium filled tubes which are used as a series of skin markers when imaging the spine. We have found this device particularly useful for imaging the thoracic spine in cases of cord compression.
A fishy tale? Carotid artery perforation following a meal of haddock: was the culprit a fish bone?
Authors: Taylor W J , Platts A D , Hamilton G
Published: July 2009

A 63-year-old gentleman was admitted to hospital complaining of progressive neck swelling, with bruising and increasing difficulty in swallowing. These symptoms were preceded by a severe bout of coughing. The night prior to admission he had eaten a meal of haddock, had woken well but then experienced the bout of coughing. He had a past medical history of polycythaemia which was treated with busulphan and regular venesection.

Examination revealed a distressed patient with massive pulsatile swelling on the right side of his neck. The overlying skin was bruised. His blood pressure measured 150/80. His voice was soft, but there was no stridor. The rest of the examination was unremarkable. A contrast computed tomography (CT) examination was performed (Figure 1). The patient proceeded to angiography (Figures 2, 3 and 4). What is the diagnosis?
Book reviews
Authors: Hately W
Published: July 2009

This is the first of a series of books on obstetric ultrasound aimed at highlighting important advances as they are reported from many disciplines across the world literature. The editors consider that the rapid pace of development in obstetric ultrasound demands prompt recording and authoritative review.

This 300 page volume includes contributions from over 20 internationally recognized authorities. The detection of fetal abnormalities in the first trimester using transvaginal scanning and the finding of markers for fetal chromosomal abnormalities are both well described. The fetal lung and dilated urinary tract are particular subjects dealt with in detail in this first volume.
Uptake of pentavalent technetium-99m dimercaptosuccinic acid by pigmented villonodular synovitis: comparison with computed tomography, magnetic resonance imaging and gallium-67 scintigraphy
Authors: Kobayashl H , Kotoura Y , Hosono M , Sakahara H , Yamamuro T , Endo K , Konishi J
Published: July 2009

The scintigraphic findings of a patient with pigmented villonodular synovitis are described and compared with the computed tomography and magnetic resonance imaging data. Intense uptake of pentavalent technetium-99m dimercaptosuccinic acid without gallium-67 citrate uptake indicates that pigmented villonodular synovitis has the features of a hyperplastic or neoplastic lesion rather than an inflammatory lesion from the point of view of nuclear medicine.
Imaging studies for emphysematous pyelonephritis
Authors: Chaudhuri T K , Fink S
Published: July 2009

We wish to comment on an article by Christensen and Bistrup [1]. The article emphasizes the importance of ultrasound (US), computed tomography (CT) and intravenous urography (IVU) in the diagnosis of emphysematous pyelonephritis (EPN).

While US and CT provide excellent anatomical information (including the degree and extent of gas-collection in EPN) about the renal parenchyma and its surroundings, they do not provide physiological, pathophysiological and functional information about the nephron.
Computerized strain-gauge plethysmography in the diagnosis of symptomatic and asymptomatic venous thrombosis
Authors: Warwick D J , Thornton M J , Freeman S , Bannister G C , Glew D , Mitchelmore A E
Published: July 2009

This study compares the results of a computerized strain-gauge plethysmograph with ascending lower limb venography in 94 patients with clinical deep venous thrombosis, and in 121 patients with asymptomatic legs being screened after total hip replacement. In the symptomatic patients, strain-gauge plethysmography had a sensitivity of 100%, an accuracy of 73%, a specificity of 64% and a negative predictive value of 100% for thrombosis above the popliteal confluence. In the screened patients, the figures were 38.1%, 55.4%, 60.0% and 81.1% respectively. Computerized strain-gauge plethysmography is a safe, non-invasive, reliable and portable method of excluding proximal thrombosis in a symptomatic patient. It avoids the need for urgent venography when anticoagulation therapy is reserved for those with proximal thrombosis. The device was not valuable as a screening tool after total hip replacement, since it had a low specificity and did not reliably detect the non-occlusive mural femoral thrombi which typically follow this procedure.
Low-reflectivity periportal collar on hepatic ultrasound
Authors: Worthy S A , Elliott S T , Bennett M K
Published: July 2009

A low attenuation periportal collar is frequently found on computed tomography (CT) in association with a variety of liver diseases and other conditions (Lawson, T L, Thorsen, M K, Erikson, S J et al, Periportal halo: a CT sign of liver disease, Abdom. Imaging, 18, 42–46 (1993)). Abnormal periportal intensity has been reported on magnetic resonance imaging (MRI) in various hepatobiliary diseases. Transient low reflectivity periportal cuffing has recently been described and was presumed to be due to periportal lymphoedema associated with malignant lymphadenopathy. We report the finding of such bands in four patients with chronic hepatobiliary disease and present the associated histological findings.
Ultrasound quantitation of respiratory organ motion in the upper abdomen
Authors: Davies S C , Hill A L , Holmes R B , Halliwell M , Jackson P C
Published: July 2009

Organ motion can cause artefacts in abdominal imaging particularly with magnetic resonance imaging (MRI), and may often limit the diagnostic quality of an image. If spatial resolution and image quality are to improve in MRI and other imaging techniques, a more detailed understanding of organ motion is required. Despite the importance of organ motion little quantitative information is available to date. This study was the continuation of work instigated to investigate and quantify respiratory movements of upper abdominal organs for a group of healthy volunteers in order to provide the design criteria for a motion test object for use in MRI. A previous phase of the project allowed construction of a test object but refinements were needed to represent respiratory motion more closely as a consequence of the data presented in this paper. Improvements in the scanning technique and the recording procedure have revealed that, contrary to our initial findings, motion of the diaphragm and liver is predominantly in the superior-inferior (SI) direction with an average displacement (± SD) (quiet respiration) of 12 ± 7 mm (range 7–28 mm) and 10 ± 8 mm (range 5–17 mm), respectively. For some volunteers, motion of the kidneys can be complex, especially during deep inspiration. New data have been provided by this phase of the motion study on the displacement, velocity and acceleration of abdominal organs as a function of time. These data show that MRI motion artefact reduction techniques which assume that either organ displacement, velocity or acceleration are constant are only applicable during certain phases of the respiratory cycle.
Reduction of radiation doses in leg lengthening procedures by means of audit and computed tomography scanogram techniques
Authors: Romanowski C A J , Underwood A C , Sprigg A
Published: July 2009

Children with congenital bone dysplasias may benefit from leg lengthening procedures. Such procedures, by necessity, require frequent and regular imaging. It is necessary to minimize the total radiation dose to these patients, and particularly the dose to the gonads. In the present study the films of 13 patients who had completed leg lengthening procedures were reviewed. The number of films was assessed together with the use of appropriate gonad shielding. In a second part of the study, thermoluminescent dosemeter measurements of radiation doses to a phantom were made for both plain radiographs (with and without gonad protection) and computed tomography (CT) scanograms. The results show that audit plays an important role in assessing radiographic practice with respect to accurate placement of gonad protection and confirm that a significant dose reduction can be accomplished by careful use of this lead shielding. Dose reduction can also be achieved by using alternative radiographic techniques such as CT scanograms. Other techniques such as ultrasound or dual-energy X-ray absorptiometry are briefly discussed. These may play an important additional part in the reduction of total radiation dose to the patients.
Reconstruction of images from radiofrequency electron paramagnetic resonance spectra
Authors: Smith C M , Stevens A D
Published: July 2009

This paper discusses methods for obtaining image reconstructions from electron paramagnetic resonance (EPR) spectra which constitute object projections. An automatic baselining technique is described which treats each spectrum consistently; rotating the non-horizontal baselines which are caused by stray magnetic effects onto the horizontal axis. The convolved backprojection method is described for both two- and three-dimensional reconstruction and the effect of cut-off frequency on the reconstruction is illustrated. A slower, indirect, iterative method, which does a non-linear fit to the projection data, is shown to give a far smoother reconstructed image when the method of maximum entropy is used to determine the value of the final residual sum of squares. Although this requires more computing time than the convolved backprojection method, it is more flexible and overcomes the problem of numerical instability encountered in deconvolution. Images from phantom samples in vitro are discussed. The spectral data for these have been accumulated quickly and have a low signal-to-noise ratio. The results show that as few as 16 spectra can still be processed to give an image. Artifacts in the image due to a small number of projections using the convolved backprojection reconstruction method can be removed by applying a threshold, i.e. only plotting contours higher than a given value. These artifacts are not present in an image which has been reconstructed by the maximum entropy technique. At present these techniques are being applied directly to in vivo studies.
Intestinal perforation—an unusual complication of endoscopic biliary stenting
Authors: D'Costa H , Toy E , Dennis M J S , Brown C
Published: July 2009

The endoscopic placement of stents to decompress biliary obstruction is accepted practice in the management of malignant biliary strictures. In our patient, a 73-year-old man with a presumed malignant common hepatic duct stricture, palliation of his obstructive jaundice has been achieved. However, his clinical course was complicated by a colonic perforation—a previously unreported complication of distal stent migration.
The application of dose–volume histograms to the Paris and Manchester systems of brachytherapy dosimetry
Authors: Langmack K A , Thomas S J
Published: July 2009

When the geometry of an implant does not exactly follow a system of dosimetry problems arise in choosing a treatment dose rate. This study has investigated the use of natural dose–volume histograms (DVHs) as a means for choosing the treatment dose level in these cases. A number of ideal geometrical cases have been investigated. For these, where appropriate, the Paris or Manchester dose rates have been calculated and compared with the peak position of the natural DVH. The dose rate at the peak of the DVH was found to agree with the basal dose rate calculated according to the Paris rules. For implants that completely obeyed the Paris rules the mean ratio was 1.009 ± 4%. A series of clinical implants was also examined. For these the mean ratio was 1.002 ± 2.5%. It is concluded that the peak position of a DVH can be used to predict the Paris basal dose rate of an implant. There was no systematic relationship found between the Manchester dose rate and the peak position of the DVH. The mean ratio between the Manchester dose rate and the peak dose rate position of the DVH was 0.82 ± 13% for a series of implants.
Improved image quality utilizing dual plate computed radiography
Authors: Workman A , Cowen A R
Published: July 2009

A method of improving image quality in computed radiography (CR) using dual plate exposure has been developed. Two CR image plates are used to increase the fraction of X-ray quanta absorbed from the beam. Spatial registration and combination of images from the two plates leads to an image with improved signalto-noise ratio characteristics. A cross correlation technique is used to register spatially the images from the front and rear plates. The modulation transfer function and noise power spectrum were measured for the single plate and combined dual plate images. Results indicate a potential increase of approximately 60% in the detective quantum efficiency (DQE) of the dual plate combined image compared with the single plate image. The improvement of DQE at high spatial frequencies is dependent on the accuracy of the registration of the two images. The actual improvement in imaging performance was measured using a contrast detail test piece. A computerized method was used to measure the imaged detail signal-to-noise ratio of the details of different dimension. Results indicate an improvement of 21% in the signal-to-noise ratio of the details imaged with the dual plate arrangement compared with the single plate. This indicates that this technique can result in a significant increase in image quality for the same exposure level. Alternatively this technique could allow reduction in exposure while maintaining the same image quality achievable with the single plate system.
Lipoma arborescens of the sub-deltoid bursa
Authors: Dawson J S , Dowling F , Preston B J , Neumann L
Published: July 2009

Lipoma arborescens is a rare synovial disorder which principally affects the knee joint. We describe an unusual case of lipoma arborescens arising within the sub-deltoid bursa in association with a rotator cuff tear. Pre-operative diagnosis was made by magnetic resonance imaging.
Paediatric intramuscular haemangiomata—don't overlook the phlebolith!
Authors: Morris S J , Adams H
Published: July 2009

Three children presented with soft tissue masses which were clinically suspected to be soft tissue sarcomas. The identification of phleboliths on initial radiological studies should have suggested the correct diagnosis of benign intramuscular haemangiomata. Subsequent referral to a paediatric oncological unit, and the unnecessary parental anxiety so generated, could have been avoided.
The addition of carbogen and nicotinamide to a palliative fractionation schedule for locally advanced breast cancer
Authors: Pigott K , Dische S , Saunders M I
Published: July 2009

Tumour cell hypoxia is a recognized cause of resistance to radiotherapy. Using clinically relevant dose-fractionation schedules in a mouse tumour model, the addition of carbogen and nicotinamide to overcome chronic and acute hypoxia results in a marked increase in radioresponsiveness with a lower degree of sensitization in normal tissue. Carbogen and nicotinamide were added to the palliative radiation treatment given to six patients with locally advanced breast cancer. The aim of the pilot study was to determine if patients tolerated the addition of carbogen and nicotinamide and to assess if there was any increase in radiosensitivity of the skin. Patients received 30 Gy prescribed to the intersection dose in six fractions over 17/18 days with full skin bolus to the tumour. All patients were given 6 g of nicotinamide orally 90 min before radiation treatment. Carbogen breathing was started 5 min prior to treatment and continued during it. Patients tolerated the treatment well, with vomiting in one patient being the only side effect that could be related to the nicotinamide, and this settled with an anti-emetic. No increase in skin reaction was noted with the addition of carbogen and nicotinamide, and good tumour regression was achieved.
Radiation dose to the lens from CT brain scans in general radiology departments
Authors: Maclennan A C
Published: July 2009

Further to the paper on radiation dose to the lens from computed tomography (CT) in a neuroradiology department [1], I report the lens dose from brain scans in general radiology departments. The materials and methods were similar to the previous paper, i.e. subjects were unselected inpatients and outpatients undergoing routine scanning, thermoluminescent dosimeters were used for measurement, and statistical calculations used the Confidence Interval Analysis program (BMJ Publishing Group, London). The scan protocols are given in Table I and the results in Table II.
Identifying and aspirating hip effusions
Authors: Berman L , Fink A M , Wilson D , McNally E
Published: July 2009

Ultrasound has become a routine investigation in the investigation of the painful hip in children. It has been recommended that all effusions demonstrated by sonography be drained. Based on the experience of 800 hip aspirations, the authors describe an approach to the demonstration and aspiration of hip effusions with some of the pitfalls that result in false positive and false negative diagnoses.
Pseudo-pseudo-obstruction
Authors: Chakraverty S C , Siddiqui K H , Griffin S M
Published: July 2009

A 63-year-old man had recently undergone subtotal oesophagectomy for squamous carcinoma of the oesophagus. He had undergone a Heller's myotomy for achalasia of the oesophagus 30 years previously. A barium study was performed to evaluate post-operative swallowing and regurgitation problems. Unusual appearances were noted in the abdomen during screening. Plain films were taken after completion of the upper gastrointestinal study (Figure 1) and 2 days later (Figure 2).
Radiotherapy for Stages I and II testicular seminoma: results and morbidity in 238 patients
Authors: Vallis K A , Howard G C W , Duncan W , Cornbleet M A , Kerr G R
Published: July 2009

We have undertaken a retrospective analysis of 238 patients with Stages I and II seminoma of the testis treated with radiotherapy in Edinburgh between 1974 and 1989. There were five deaths from seminoma. Cause-specific survival for the whole group at 2 and 5 years was 99.2% and 98.1%, respectively. Causespecific survival at 2 and 5 years by stage (Royal Marsden staging classification) was: Stage I, 99.5% and 98.7% and Stage II, 98.1% and 96.1%. Fourteen (5.9%) patients relapsed (one after treatment for his second testicular seminoma). Eight were given successful salvage treatment, five died of seminoma and one died of intercurrent disease. 13 (5.5%) patients developed World Health Organisation (WHO) grade 3 gastrointestinal or haematological toxicity and two developed grade 4 gastrointestinal toxicity as a result of abdominal radiotherapy. 22 patients (9.2%) developed problems ascribed to late morbidity of abdominal radiotherapy including 18 with peptic ulcer disease. Contralateral testicular tumours occurred in seven (2.9%) patients and five (2.1%) patients developed malignancies at other sites.
Intraventricular meningioma with cerebellopontine angle and drop metastases
Authors: Peh W C G , Fan Y W
Published: July 2009

A 34-year-old Chinese woman underwent successful gross total excision of a benign fibroblastic meningioma, pre-operatively diagnosed by computed tomography (CT), arising from the left lateral ventricle of the brain. After a quiescent period of 5 years, CT and magnetic resonance imaging (MRI) demonstrated tumour recurrence at the same site. Despite two further excisions of progressively malignant intraventricular meningiomas and treatment with radiotherapy, the patient rapidly developed bilateral cerebellopontine angle and spinal drop metastases. CT and MRI were useful in demonstrating the location and extent of recurrent intraventricular meningiomas, as well as metastatic spread via the cerebrospinal fluid.
Mammographic features of invasive lobular and invasive ductal carcinoma of the breast: a comparative analysis
Authors: Cornford E J , Wilson A R M , Athanassiou E , Galea M , Ellis I O , Elston C W , Blamey R W
Published: July 2009

The mammographic appearances of 86 invasive lobular carcinomas were compared with those of 86 invasive ductal carcinomas of no special type matched for age, size and stage. There was no significant difference in the frequency of a mammographic abnormality consistent with malignancy between the lobular carcinoma (90%) and ductal carcinoma (96%) groups. A spiculate mass was the commonest feature in both groups (69% and 63%, respectively). There were no differences in the imaging features of masses in the two groups. In the lobular carcinoma group any mammographic abnormality was more likely to be seen on only one view and calcifications were less frequently observed. Multiple lesions were more frequent in the ductal carcinoma group. However, although these differences appeared to reach statistical significance, as they were only apparent in a study with a large number of comparisons, it is unlikely that these differences are practically significant. Analysis of the lobular invasive group failed to demonstrate any significant differences in the imaging features of the classical and mixed sub-types, a spiculate mass being the most common single abnormality in both. No mammographic differences of practical use to distinguish invasive lobular from invasive ductal carcinoma of no special type were demonstrated.
Dosimetric considerations in 131I-MIBG therapy for neuroblastoma in children
Authors: Bolster A A , Hilditch T E , Wheldon T E , Gaze M N , Barrett A
Published: July 2009

Dosimetric calculations have been made for organ doses in patients receiving 131I-MIBG therapy as treatment for neuroblastoma. As well as whole body and liver dose, consideration has been given to dosimetry of organs (lung, urinary bladder) whose tolerance may become treatment limiting when 131I-MIBG is given as part of combined modality therapy. Data from both adults and children receiving radiolabelled MIBG for diagnostic or therapeutic purposes have been compared in constructing dosimetry models for children. A recently published urodynamic model has been used in the estimation of radiation dose to the bladder. The results show that liver and lung may receive doses greater than the average total body dose (0.58 mGy MBq−1 and 0.35 mGy MBq−1, respectively, as compared with 0.25 mGy MBq−1 to the whole body). The organ dose estimates do not differ greatly from previous analyses except in the case of the bladder for which the new modelling studies have resulted in lower dose estimates (0.76 mGy MBq−1 administered, for dose to bladder surface from bladder contents) than in some published series. This may result from differing assumptions regarding parameters such as bladder content and urine flow rate, an enhanced fluid intake being assumed in the present bladder dose estimates. Average doses to the bladder wall from the contents were estimated to be 7.4–11.3% of the surface doses. The urodynamic modelling analysis shows that the bladder could receive a much greater dose (by an order of magnitude) in patients who were inadequately hydrated or had impaired renal function.
Patient and staff dosimetry in neuroradiological procedures
Authors: Marshall N W , Noble J , Faulkner K
Published: July 2009

Cerebral angiography provides valuable information for use in the clinical management of patients but can result in relatively high radiation doses to patients and staff due to the extended fluoroscopy time and number of images acquired during an examination. In this study, extremity doses to radiologists and scrub nurses working in a neuroradiological centre were monitored during a 3 month period using thermoluminescent dosemeters (TLDs). Electronic personal dosemeters were also used to monitor doses above the lead apron at chest height to the radiologists, radiographers and the scrub nurses. Patient doses were recorded using a dose–area product meter whilst patient thyroid dose was measured using TLDs. Two types of examination were studied: cerebral angiography and arterial embolization. It was deduced from the results of the study that the radiologist may expect to receive a mean dose above the lead apron at chest height of 11 μSv and 25 μSv per examination when performing cerebral angiography and arterial embolization, respectively. A radiologist mean hand dose of 19.3 μSv per examination was found, whilst the average eye dose for both radiologist and scrub nurse was 13.4 μSv per examination. The patient dosimetry results revealed a mean thyroid dose of 1.7 mSv and a dose–area product of 48.5 Gy cm2 for cerebral angiography. Average dose–area product for arterial embolization was 122.2 Gy cm2 along with a mean patient thyroid dose of 3.3 mSv.

More detailed patient dosimetry was also performed using a Rando anthropomorphic phantom loaded with TLDs to measure organ doses and hence estimate effective dose. A typical four vessel angiogram was found to result in a patient effective dose of 3.6 mSv.
Compression stockings and posture: a comparative study of their effects on the proximal deep veins of the leg at rest
Authors: Macklon N S , Greer I A
Published: July 2009

Graduated compression stockings have been shown to reduce the incidence of deep venous thrombosis. While they are thought to act primarily by increasing venous flow velocity, their mode of action remains uncertain. Doppler ultrasound was employed to study the relative effects of three types of support stocking on the deep venous diameter, flow velocity and pulsatility in 10 non-pregnant female subjects. In addition, the effect of altered posture on the same parameters was assessed. Significant effects of the graduated stockings were found at the level of the popliteal vein, where a reduction in both the diameter and the amplitude of respiratory phasicity was recorded (p<0.05). No significant increase in flow velocities was recorded. Adopting the left lateral position significantly increased flow velocity in the right common femoral vein (p<0.05). The application of stockings in this position produced no additional increase in flow velocities, but did alter the amplitude of respiratory phasicity. These data do not support the widely held view that graduated compression stockings increase flow velocities at rest. Adopting a lateral recumbent position significantly increases flow velocity in the non-dependent leg.
Digital radiographic pelvimetry—a novel, low dose, accurate technique
Authors: Wright D J , Godding L , Kirkpatrick C
Published: July 2009

A technique is described for lateral pelvimetry which results in a lower radiation dose than that resulting from conventional film–screen pelvimetry and computed tomography (CT) pelvimetry. It uses digital radiographic imaging thereby closely matching conventional techniques yet additionally providing post-processing facilities including distance measurement and contrast adjustment. The digital technique was evaluated with an anthropomorphic phantom and compared with the conventional technique by measuring entrance surface doses on two groups of post-natal patients. Digital radiography gave radiation doses 10 times lower than those using conventional techniques.
Variable imaging appearances of angiomyolipomas of the liver
Authors: Peh W C G , Ngan H , FAN S T , NG I O L
Published: July 2009

Angiomyolipomas of the liver are rare benign tumours. We describe the variable imaging appearances of these tumours in three women. The first two patients underwent ultrasound, computed tomography (CT) and angiography, which demonstrated lesions resembling focal nodular hyperplasia and hepatocellular carcinoma, respectively. Both had histologically-proven liver angiomyolipomas surgically resected. The third patient was incidentally found to have typical features of multicomponented liver angiomyolipoma on CT. Variable proportions of fatty tissue in these tumours are the most likely explanation for their different imaging appearances on CT.
Some experiments upon the biological effects of fast neutrons
Authors: Gray L. H. , Mottram J. C. , Read John , Spear F. G.
Published: July 2009

The spatial distribution of ions in a medium traversed by neutrons is markedly different from that resulting from ionisation by γ rays or X rays. This fact has led a number workers to study the biological effects of neutrons, especially in relation to the effects produced the better-known ionising agents, in the hope that any differences which were found might provide a clue to the understanding of the general problem of the biological action ionising radiations. The experiments have also had certain more immediate practical objectives. Fast neutrons have a power of penetration through soft tissue comparable with that of hard X rays, so that marked differences in the nature of the response of normal and neoplastic tissue might be used to advantage in cancer therapy. Furthermore, the development of increasingly powerful neutron sources biologically equivalent to perhaps a kilogramme of radium has made the study of the biological effects of these rays important from the point of view of the protection of the workers.
Model based calculation for effective cancer radioimmunotherapy
Authors: Attard A R , Chappell M J , Bradwell A R
Published: July 2009

The major problem of tumour radioimmunotherapy remains the low tumour antibody uptake and this leads to inadequate tumour irradiation. The antibody characteristics which influence uptake have been identified and quantified previously using a non-linear compartmental model that simulates antibody distribution to tumour and body after intravenous injection. The model has now been extended, in combination with MIRD dosimetry tables, to calculate the integral tumour/body radiation dose for a range of antibody masses (1, 10 and 50 mg), sizes (binding site fragments and whole molecules) and affinities (K = 109–1013 mo1−1). Antibody requirements for delivering 60 Gy to the tumour over 11.6 days were calculated for 131I and 90Y-labelled antibodies and included the effect of widely varying dose rates. The model predicted that intact antibodies of high affinity (1011–1013mo1−1) produced effective tumour radiation doses with acceptable whole body radiation levels. By contrast, antibody fragments gave higher body radiation levels and required larger injected activity because of renal excretion. The model predicted higher therapeutic indices for 90Y-labelled antibody compared with 131I.
Mesenteric mixed haemangioma and lymphangioma; report of a case with 10 year follow-up after radiation treatment
Authors: Tai P T H , Jewell L D
Published: July 2009

A patient with massive mixed haemangioma and lymphangioma of the mesentery first presented in childhood with ascites which subsided spontaneously and, subsequently, at 21 years of age, presented with gastrointestinal bleeding. At laparotomy, the lesion was found to involve 90% of the mesentery and was unresectable due to its bulk. Hence he was treated by radiotherapy (15 Gy/15 fractions/3 weeks followed by a boost of 5 Gy/4 fractions/4 days). He responded to the treatment. 10 years later he again experienced mild gastrointestinal bleeding which subsided spontaneously. This case illustrates the efficacy of radiotherapy in massive mesenteric haemolymphangiomas. Review of the literature revealed that surgical excision, embolization, and radiotherapy have been used in the treatment of haemangiomas and lymphangiomas. In unresectable cases, radiotherapy has a definite role in the management. A variety of doses has been employed in the literature. No definite dose–response relationship was identified.
Are moving junctions in craniospinal irradiation for medulloblastoma really necessary?
Authors: Tinkler S D , Lucraft H H
Published: July 2009

The case notes of 35 patients treated for medulloblastoma using a standard technique of craniospinal irradiation (CSI) from 1978 to 1992 were reviewed. Two large opposed lateral fields to the whole brain and an orthogonal posterior spinal field were used. The position of the junction between the fields was constant throughout treatment with no feathering and no gap. We present our results, review the literature and discuss the need for feathering. The junction between the cranial and spinal fields produces an area of dose inhomogeneity but the clinical significance of this and the effect of feathering is uncertain.
An estimate of the margin required when defining blocks around the prostate
Authors: Jones D , Hafermann M D , Rieke J W , Vermeulen S S
Published: July 2009

The portal films of 54 consecutive patients treated for primary prostate cancer have been compared to the simulation films. The systematic and random uncertainty in the set-up, defined by the couch movement required to move the patient to the simulated position, was determined to be 1.6 mm UP (SD 3.3 mm), 0.3 mm RT (SD 2.6 mm) and 1.3 mm IN (SD 2.4 mm). The area of fields defined on simulation films was compared with that on portal films to determine the error in block production which was –0.7 mm (SD = 0.9 mm). Five sources of uncertainty in the radiotherapy have been identified, three occur before and two during the course of treatment. A method for combining these uncertainties is proposed and used on the data obtained in this study. This provides estimates of the margin required when drawing blocks so that the minimum dose to the target is 95% of the prescription in 95% of treatments. The block margins are not uniform and range from 21 mm, when drawing the block outline to the posterior on a lateral film, to 13 mm when drawing laterally on an anterior film.
Air versus carbon dioxide insufflation in double contrast barium enemas: the role of active gaseous drainage
Authors: Farrow R , Jones A M M , Wallace D A , Virjee J P
Published: July 2009

Air has been traditionally used as the negative contrast agent in double contrast barium enema (DCBE) examinations, but causes abdominal pain in the 24 h following the procedure. The frequency of post-procedural pain is less when carbon dioxide (CO2) is used as the negative contrast agent. We evaluated patients following DCBE examinations (using either air or CO2) by means of a questionnaire, to determine whether active drainage of gas altered the post-procedural pain. There was no difference in the pain experienced in the groups receiving CO2 with either active or passive drainage, or in the group receiving air with active drainage. Compared with the other groups there was a significantly higher incidence and severity of pain in the group receiving air and passive drainage. We conclude that active drainage of air following a DCBE examination is as effective as using CO2 in reducing post-procedural pain and swelling.
Derivation of the optimum dose per fraction from the linear quadratic model
Authors: Jones B , Tan L T , Dale R G
Published: July 2009

The linear quadratic equation for fractionated radiotherapy has already been adapted to include a time factor for tumour repopulation: loge cell kill (E) is given as a function of dose per fraction (d), number of fractions (n), overall treatment time (T) and the clonogen doubling time (Tp). By incorporating a normal tissue isoeffect and replacing the relationship between T and n by a function f, the equation for E can be rewritten as a more complex function of d. In this form, E and d are continuous variables so that the dose per fraction (d′) required to produce maximum values of E for isoeffective late normal tissue effects can be found by differential calculus. The derived equation takes the form and when solved for d provides a direct estimation of the optimum dose per fraction. Where normal tissue sparing is possible and the tumour dose z is related to the normal tissue dose d, the optimum dose per fraction z′ can be found by solving the equation The results show that a critical minimum dose per fraction is required to counteract rapid tumour clonogen repopulation in both conventional and accelerated radiotherapy. The calculus method is reasonably accurate for larger fraction numbers, when clonogen doubling times are 3.5 days or longer and for conventional radiotherapy given 5 days per week. The model is even more accurate for accelerated hyperfractionated radiotherapy providing that there is complete repair between successive fractions. Where greater normal tissue sparing is possible, as with focal teletherapy methods and brachytherapy, higher tumour doses per fraction can be used to increase further the tumour cell kill without exceeding normal tissue tolerance. These predicted doses per fraction are consistent with clinical experience when the given constraints in terms of frequency of treatment are considered. The model described can be used for tumours in which repopulation occurs at a constant rate throughout treatment. For tumours in which accelerated repopulation occurs, the optimum dose per fraction can be separately calculated for the initial phase of slow repopulation (for which very small doses per fraction are optimal) and also for the second phase of rapid repopulation (for which either accelerated hyperfractionated treatments or hypofractionated focal methods of treatment would be appropriate). The limitations of the model are fully discussed including the need for accurate radiobiological predictive assays. In the future such assays of pre-treatment doubling times and tumour cell radiosensitivities could be used to determine reasonable ranges for the optimum dose per fraction in experimental tumours and subsequently in clinical trials. This approach could produce major improvements in the therapeutic potential of radiotherapy.
Dual energy X-ray absorptiometry normal reference range use within the UK and the effect of different normal ranges on the assessment of bone density
Authors: Simmons A , Barrington S , O'Doherty M J , Coakley A J
Published: July 2009

The number of different normal ranges used on dual energy X-ray absorptiometry (DEXA) machines in the United Kingdom was determined by means of a postal questionnaire. Both femoral neck and posteroanterior spine L2–L4 regions were considered. It was clear from this survey that a variety of normal ranges were in use for all manufacturers of DEXA systems. The effects of four normal ranges supplied by Norland for use within the UK on the stratification of over 1000 consecutive patients into different grades of bone mineral density (BMD) and Z-score were examined. The main outcomes measure the number of patients with BMD less than 80% of mean age-matched BMD and Z-score less than – 1.5 over the femoral neck and spine for each normal range. The percentage of patients for each normal range with BMD less than 80% of mean for the femoral neck were 24.6%, 7.4%, 17.5% and 11.1% and for the spine 12.1%, 7.4%, 16.5% and 14.4%, respectively. For the femoral neck, 21.2%, 5.0%, 12.9% and 12.1% of patients had Z-scores of less than – 1.5, for the spine this was 7.9%, 8.1%, 14.2% and 13.6% of patients. These differences between ranges are large enough to influence patient management—patients may be diagnosed as osteoporotic using one range and normal using another. The relationship between hip and spine measurements was also studied as some therapeutic agents do not affect BMD equally at all anatomical sites. The number of patients with a lower hip than spine BMD grade varied from 12.3% to 34.4%, and with a lower hip than spine Z-score from 14.0% to 43.4%. Choice of normal range thus has a critical effect on the categorization of osteoporotic patients using DEXA. The wide variety of normal ranges indicates that there are likely to be differences in patient management throughout the country. This will be an increasing problem due to the ability of NHS purchasers to switch contracts from one provider to another.
Non-Hodgkin's lymphoma presenting as an encasing pleural mass
Authors: Parnell A P , Frew I
Published: July 2009

We report a case of primary non-Hodgkin's lymphoma of the pleura with marked pleural thickening and encasement, apparent on a chest radiograph. This has not, to our knowledge, been previously reported.
Book reviews
Authors: Kerslake R
Published: July 2009

The American College of Radiology (ACR) have published 37 diagnostic radiology syllabi over the last 23 years, four previous volumes relating to skeletal radiology. This fifth volume on musculoskeletal disease reflects in both its title and content the expanding clinical practice of imaging non-osseous as well as osseous abnormalities. The stated intentions of the contributors were to select topics of interest to a broad spectrum of radiologists, topics that were timely or those that were not adequately discussed in the usual reference sources.