bluuebunny/crossref_metadata_2025 huggingface dataset:
Effective doses to patients from paediatric cardiac catheterization.
Authors: Rassow J , Schmaltz A A , Hentrich F , Streffer C
Published: June 2014

The Council Directive of the European Communities 97/43/Euratom requires dose assessment, especially for X-ray examinations of children and if high doses to the patient are involved. Both these aspects apply in cardiac catheterization and angiocardiography of children. Effective doses are a good indicator of radiation risk, particularly for leukaemia. Effective doses have been determined for 2114 infants and children undergoing cardiac catheterization from 1984 to 1996 at the University Hospital in Essen. Conversion factors (effective dose/dose-area product) were calculated based on direct dose-area product measurements for posteroanterior (PA) and lateral (Lat) projections as well as on patient records and examination details. The factors are calculated for eight age groups of children, taking into account the X-ray tube voltage for fluoroscopy and cine-film sequences, with and without zoom mode. Frequency distributions are presented for 2114 patients, for dose-area product, number of angiographic examinations (each combined with one cine-film sequence both PA and Lat) and for calculated effective doses. Highest effective doses are found in newborns (18.0 mSv and 6.5 mSv 90th and 50th percentiles, respectively) compared with adolescents of 15-21 years (8.0 mSv and 3.0 mSv 90th and 50th percentiles, respectively). Effective dose for cardiac catheterization is highest for newborns, in spite of lowest measured dose-area products, because the decreased value of the conversion factors overcompensates for the increase of dose-area product with age. This is especially important because of the higher tumour risk for equal effective dose for young children compared with adults.
Infants exposed to MRI in utero have a normal paediatric assessment at 9 months of age.
Authors: Clements H , Duncan K R , Fielding K , Gowland P A , Johnson I R , Baker P N
Published: June 2014

Any differences in detailed paediatric assessment at 9 months of age in infants exposed to echo planar MRI in utero from 20 weeks gestation to term were investigated by performing a case controlled prospective observational study of 20 infants. They had all had serial echo planar MRI in the antenatal period and were compared with a control group born at the same time who had not. Statistical analysis employed likelihood ratios, odds ratios and 95% confidence intervals. The mothers of the control infants had a significantly higher standard of educational attainment (p = 0.005). A small but significant decrease in length (p = 0.047), and an increase in gross motor function (p = 0.023) of the fetuses exposed to echo planar imaging were demonstrated. No other significant developmental or social differences were seen between the two groups. Infants at 9 months of age did not demonstrate any gross abnormality likely to be related to exposure to echo planar MRI in utero.
Calibration of pre-cut iridium-192 wires for low dose rate interstitial brachytherapy using a Farmer-type ionization chamber.
Authors: Vollans S E , Wilkinson J M
Published: June 2014

A technique, originally developed for calibrating small low activity caesium sources, which uses a Farmer-type ionization chamber, has been further developed for use with iridium wires. Correction factors have been generated to account for the finite source and detector sizes, and attenuation in the source carriers. The air kerma calibration factor for heavily filtered 280 kV X-rays was used for reference back to the National Standard. The results of this calibration method have been compared with the calibration figures given by the manufacturers over a 5 year period for the emissions from 50 batches of wires of varying strengths. Agreement to within +/- 3.2% was achieved in all cases, establishing that the method is satisfactory for acceptance testing purposes. The mean agreement was good to within 0.2%, but the possibility of a systematic error of between 1% and 3% existing both in this method and in the method used by the manufacturer is discussed.
Haemostatic effects of low osmolar non-ionic and ionic contrast media: a double-blind comparative study.
Authors: Hoffmann J J , Tielbeek A V , Krause W
Published: June 2014

In this prospective, double-blind, randomized study the effects of a non-ionic contrast medium (Iopromide) on the haemostatic system were compared with those of a low osmolar ionic medium (Ioxaglate). The aim was to investigate in vivo whether a non-ionic contrast agent is less anticoagulant or more pro-thrombotic than an ionic medium. A large number of haemostatic parameters, including activation markers, were measured. Either Iopromide (n = 16; median volume 102 ml; 95% confidence interval 90-108 ml) or Ioxaglate (n = 15; median 105 ml; 95% confidence interval 95-114 ml) was given to 31 patients scheduled for abdominal and femoral arteriography. Blood for laboratory investigations was collected before, and 5 and 30 min after, administering the contrast medium. Indications for activation of coagulation and platelets were already found in nearly 50% of the patients before any contrast medium was given. Both Iopromide and Ioxaglate caused further increases in thrombin-antithrombin complex, prothrombin fragments 1 + 2 and beta-thromboglobulin. The degree of activation was similar for both agents. Anticoagulant effects were not observed. The haemorheological effects were compatible with haemodilution by 5-8%, again without differences between the contrast agents. Contrary to the findings from in vitro studies, we found no significant differences between the effects of the non-ionic Iopromide and the ionic Ioxaglate on coagulation and platelets. Both agents activated these systems to a limited, but identical, degree. Our results support the notion that the catheterization procedure per se may represent a source of haemostatic activation and that the ionic contrast agent studied has insufficient anticoagulant effect to prevent clotting activation being induced by the contrast medium.
Peripheral quantitative CT of the forearm: scanner cross-calibration using patient data.
Authors: Grampp S , Nather A , Rintelen B , Henk C , Resch-Holeczke A , Imhof H , Resch H
Published: June 2014

Bone density measurements by peripheral quantitative CT (pQCT) of the distal radius in 87 women (age 38.4 +/- 12.3 years) were obtained on a both a Stratec XCT 900 and an updated version XCT 1400. Axial area, and total and trabecular bone mineral density (BMD) results from both scanners were compared for all patients using linear regression analysis. To achieve scanner calibration we used the intercept and slope of the patients' correlations. The correlations of the patients' values were good for area (r = 0.83) as well as total BMD (r = 0.90) and excellent for trabecular BMD (r = 0.97). The cross-calibration approach in our study provided compatibility of pQCT for trabecular and total ROIs, the clinically mostly utilized volumes of measurement.
A therapy beam training aid.
Authors: Seaby A W , Cravan C
Published: June 2014

Beams of X-rays and electrons used in external beam radiotherapy are characterized by differences in penetration, build-up, divergence, scatter etc. This short communication describes a very simple phosphor-loaded box that can be used to demonstrate directly to students the different properties of beams and the effect of field modifiers such as wedge filters, lead shields etc.
Investigation of dose homogeneity in paediatric anthropomorphic phantoms for a simple total body irradiation technique.
Authors: Vollans S E , Perrin B , Wilkinson J M , Gattamaneni H R , Deakin D P
Published: June 2014

The technique for treating total body irradiation patients used at the centre involves no compensation for the inhomogeneity of patient shape. Dose is prescribed to the lung, and monitor units are derived from standard data depending on the external dimensions of the patient at nipple level. Dose measurements were made during standard treatments on three paediatric anthropomorphic phantoms representing children of 5, 10 and 15 years of age. The results confirmed that the measured dose to the lung was within 4% of the prescribed dose, and dose homogeneity was within +/- 5%, excluding the neck, where the higher measured doses were still within tissue tolerance.
Congenital diaphragmatic herniation: antenatal detection and outcome.
Authors: Dillon E , Renwick M , Wright C
Published: June 2014

201 fetuses and babies with a congenital diaphragmatic herniation or eventration (referred to collectively as CDH) were notified to the Northern Region Congenital Abnormality Survey (NorCAS) in the 13-year period from 1985 to 1997, an incidence of 0.25 per 1000 births. The 1-year survival of all pregnancies associated with CDH was 37%. The 1-year survival of livebirths was 50%. Antenatal scan detected the diaphragmatic defect or associated structural abnormality in 50%. Another major structural abnormality was present in 62 (31%); one of these babies survived and 26 pregnancies were terminated. This group contained four of the six antepartum stillbirths, all three intrapartum stillbirths and four of the five spontaneous miscarriages. Non-isolated CDH occurred in association with Fryns (5), Goldenhar (1) and de Lange (1) syndromes, and in 16 of 17 with a chromosome anomaly. 53% of the 139 fetuses with isolated CDH survived to 1 year of age, and 59% of the 124 liveborn survived. Of 37 fetuses with isolated CDH detected before 25 weeks gestation, 12 pregnancies were terminated. There were 11 survivors among the 25 continuing pregnancies (44%). The overall survival of babies with CDH is very poor but, when a defect is identified by ultrasound before 25 weeks gestation, chromosome analysis and a careful ultrasound scan may suggest which fetuses have an isolated diaphragmatic abnormality and a greater chance of survival.
The chest radiograph appearances of very premature infants at 36 weeks post-conceptional age.
Authors: Greenough A , Dimitriou G , Johnson A H , Calvert S , Peacock J , Karani J
Published: June 2014

The chest radiograph of very premature infants at 36 weeks post-conceptional age (PCA) was evaluated with regard to the degree of hyperinflation and cardiomegaly, and the presence of fibrosis/interstitial shadowing, cystic elements, air bronchograms and opacification. The evolution of abnormalities was assessed by comparing the radiograph appearance at 36 weeks PCA with that at 28 days post-natal age (PNA). Three scoring systems were used to determine how any abnormalities present could be best quantified to reflect disease severity as determined by chronic dependency upon supplementary oxygen status. Chest radiographs at 36 weeks PCA from 60 infants (median gestational age 26 weeks (range 24-28)) were studied. 47 infants also had radiographs at 28 days PNA. Only three infants had no chest radiograph abnormalities at 36 weeks PCA, although 24 infants were not dependent upon supplementary oxygen. The most common abnormalities were interstitial shadowing and hyperinflation, while cystic elements and cardiomegaly were rare. The radiographic appearance had deteriorated from 28 days PNA to 36 weeks PCA (p < 0.05); more infants at 36 weeks PCA were hyperinflated (p < 0.01). The chest radiograph appearances of infants who were dependent upon supplementary oxygen scored higher than those who were not (p < 0.01) using all three scoring systems. The system that assessed only the presence of interstitial shadowing, cystic elements and hyperinflation had the highest specificity in identifying oxygen dependency beyond 36 weeks PCA and had the highest area under the respective receiver operator characteristic curve. In conclusion, the majority of very immature infants have an abnormal chest radiograph appearance at 36 weeks PCA. The appearance can, however, be meaningfully scored by evaluating only three abnormalities.
Skin edge perception in mammograms: a comparison of two film-screen combinations.
Authors: Meeson S , Young K C , Cooke J
Published: June 2014

The entire skin edge is not always seen on mammograms. The importance of demonstrating the full extent of the breast on a mammogram is uncertain, but there are implications for optimizing film design and use. The new Agfa HDR film has been designed to improve visualization of the skin edge without compromising overall contrast. A quantitative and qualitative comparison between Agfa HDR and the Fuji UMMA film has been performed. A total of 216 mammograms from 54 symptomatic women were analysed. For each view on each woman, one breast was imaged using Fuji UMMA film and the other using Agfa HDR film. The target density achieved on quality control films of PMMA blocks was 1.70 +/- 0.10 for both film types. A radiologist graded the skin edges of all the films as visible, just visible or dark. Measurements were made of the optical densities in the skin edge region and on the fully exposed black part of the film, adjacent to the skin line. 70% of the HDR films had visible skin edges compared with 43% of the UMMA films. 2% of the HDR films had dark skin edges compared with 26% of the UMMA films. Optical densities at the skin edge were broadly similar for the two films and in the range 3.6 +/- 0.3. However, the density of the black part of the Agfa film was about 0.5 higher than with the Fuji film and it appears that this was the main reason the skin edge region was better visualized with the Agfa film.
A digital density equalization technique to improve visualization of breast periphery in mammography.
Authors: Stefanoyiannis A P , Costaridou L , Sakellaropoulos P , Panayiotakis G
Published: June 2014

In mammographic imaging, the film area corresponding to the breast periphery is overexposed, resulting in high optical density and degraded contrast in this region. A digital, model-driven density equalization technique was designed and developed to overcome this overexposure problem, taking into account the non-linear characteristic curve of the film-digitizer system. The method is based on several image processing and analysis techniques, such as thresholding, which is used to segment the pixels of the mammogram belonging to the breast region from the background, and wavelet-based fusion, which is used to equalize the pixels of breast periphery selectively while leaving the remaining breast region unaffected. Initial application of the method resulted in density-equalized mammographic images, characterized by improved contrast at the breast periphery.
Magnetic resonance spectroscopy in the evaluation of neurotoxicity following cranial irradiation for childhood cancer.
Authors: Davidson A , Tait D M , Payne G S , Hopewell J W , Leach M O , Watson M , MacVicar A D , Britton J A , Ashley S
Published: June 2014

In order to evaluate the role of proton MR spectroscopy (1H-MRS) in the diagnosis and assessment of long-term radiation-related neurotoxicity, 14 children who had received cranial irradiation for the treatment of childhood leukaemia (n = 6) or brain tumours (n = 8) underwent 1H-MRS, MRI and neuropsychological assessment. Short-term effects at 2 months following treatment were studied in a further three patients. MRI abnormalities were observed in nine patients. No statistically significant differences between patients and controls (n = 17) were seen in any of the calculated 1H-MRS metabolite ratios, in any of the three patient groups. On multivariate logistic regression analysis there was a correlation between the choline/water ratio and a low IQ. It is concluded that any systematic radiation-induced changes in the 1H MRS metabolites must be below the detection threshold of this study.
The diabetic foot.
Authors: Tomas M B , Patel M , Marwin S E , Palestro C J
Published: June 2014

Foot complications in diabetics often lead to amputation. Ulceration is the most common complication in the diabetic forefoot and underlies more than 90% of cases of pedal osteomyelitis. The diagnosis of osteomyelitis is, nevertheless, difficult, and imaging is an important part of the work-up. Plain radiographs, although useful for anatomical information, are neither sensitive nor specific. Three-phase bone scintigraphy is sensitive but not specific. Labelled leucocyte scintigraphy and MRI are both useful and are complementary to one another. Labelled leucocyte scintigraphy is valuable for diagnosis as well as follow-up of pedal osteomyelitis. MRI offers exquisite anatomical detail, which is invaluable for guiding surgical management. The principal complication in the mid and hind foot is the neuropathic or Charcot joint. Although infection of the neuropathic joint is infrequent, its diagnosis is difficult. The extensive bony changes that accompany this disorder severely diminish the value of radiography and bone scintigraphy. It is not always possible to distinguish the marrow oedema of neuropathy from that of osteomyelitis and the role of MRI in the evaluation of this entity is still uncertain. Uptake of labelled leucocytes in the absence of infection may occur and is owing, at least in part, to haematopoietically active marrow. Combined leucocyte/marrow scintigraphy holds considerable promise for identifying the infected Charcot joint.
Intensity modulated radiation therapy: a clinical review.
Authors: Nutting C , Dearnaley D P , Webb S
Published: June 2014

Intensity modulated radiotherapy represents a significant advance in conformal radiotherapy. In particular, it allows the delivery of dose distributions with concave isodose profiles such that radiosensitive normal tissue close to, or even within a concavity of, a tumour may be spared from radiation injury. This article reviews the clinical application of this technique to date, and discusses the practical issues of treatment planning and delivery from the clinician's perspective.
Effects of titanium prosthesis, offset and size of field of view on bone mineral density measurements using quantitative computed tomography.
Authors: Feng Z , Ziv I , Rho J , Han S , Fishkin Z
Published: June 2014

To estimate the accuracy of quantitative computed tomography (QCT) as a method to measure bone mineral density (BMD) in the vicinity of a titanium prosthesis, we investigated the effects of (1) titanium prosthesis, (2) offset of the longitudinal axis of the bone to be examined from that of the gantry of the CT scanner, (3) size of the field of view (FOV) and (4) the combination of these effects on CT based measurements of mineral density of cortical and cancellous bone specimens. 14 bovine cortical bone parallelepipeds and 14 bovine cancellous bone parallelepipeds were used in this investigation. The bone specimens were scanned with and without a titanium prosthesis, when centered in the gantry of the CT scanner and offset from the axis of the gantry of the CT scanner at a distance of 14 cm. Image data were then reconstructed separately with a FOV of 10 cm and 30 cm. All BMD values taken from CT images obtained under different scanning condition were compared with the BMD values of the corresponding bone parallelepiped obtained under standard condition (centered in the gantry of the CT scanner, 10 cm FOV, without titanium prosthesis). When centered in the gantry of the CT scanner, the mean relative difference of BMD measurements caused by the presence of the titanium prosthesis was less than 1% for both cortical bone and cancellous bone. Size of the FOV had a negligible effect on BMD measurements. Offset at 14 cm, however, caused a significant difference in BMD measurements (p < 0.001). It was concluded that titanium prosthesis did not interfere with BMD measurements of cortical and cancellous bone when both the specimen and prosthesis were centered in the gantry of the CT scanner. However, the effect on BMD measurements of offset at 14 cm combined with the presence of a titanium prosthesis in bone was significant.
"Anode heel effect" on patient dose in lumbar spine radiography.
Authors: Fung K K , Gilboy W B
Published: June 2014

Appropriate use of the "anode heel effect" of the output beam from an X-ray tube can reduce the effective dose to patients in some common radiological examinations. We investigated the variation in radiation intensity across the X-ray beam caused by the anode heel effect, and quantified the difference in absorbed dose to critical organs resulting from lumbar spine X-ray projections carried out with the two possible orientations of the patient along the tube axis (cathode to anode). A Rando phantom and some high sensitivity thermoluminescent dosemeters (TLDs) (LiF:Mg,Cu,P) were used. With the tube axis horizontal, radiation intensity profiles, parallel and perpendicular to the axis, were measured. Lumbar spine radiographs were recorded using the Rando phantom in the standard anteroposterior (AP) and lateral projections. TLD pellets were used to measure the absorbed radiation dose at various sites corresponding to critical organ tissues (ovaries, testes, breasts, thyroid and lens). Each set of projections was recorded in two phantom orientations, first with the phantom head placed towards the cathode end of the X-ray tube, and then in the reverse direction. From the radiation intensity profile of the incident X-ray beam, the "cathode end" to "anode end" air dose ratio was found to be 1.8. In lumbar spine radiography, with the phantom head placed towards the anode end of the X-ray tube, the ovaries and testes received an average dose 17% and 12% higher, respectively, in the lateral projection, and 16% and 27% higher, respectively, in the AP projection, than those obtained in the reverse "patient" orientation. These results indicate that patients (particularly females) should always be positioned with the head placed towards the cathode end of the X-ray tube for lumbar spine radiography to achieve significant dose reductions.
Massive rise in thyroglobulin with adult respiratory distress syndrome after embolisation of thyroid cancer metastasis.
Authors: Elshafie O , Hussein S , Jeans W D , Woodhouse N J
Published: June 2014

A patient with long-standing metastatic disease from a well differentiated papillary cell carcinoma of the thyroid underwent embolisation of a painful large sacral metastasis. Following embolisation she had a massive rise in circulating serum thyroglobulin (Tg) levels coinciding with the development of adult respiratory distress syndrome (ARDS) on the tenth day without any other obvious cause. The patient subsequently recovered. The time course suggests that ARDS in this case might have resulted from aggregation of Tg molecules in the pulmonary microcirculation.
Acute appendicitis with intestinal non-rotation presenting with partial small bowel obstruction diagnosed on CT.
Authors: Zissin R , Kots E , Shpindel T , Shapiro-Feinberg M
Published: June 2014

The findings of acute appendicitis on CT have been extensively described in the literature. This is a report of a case of acute appendicitis in a patient with intestinal non-rotation presenting with partial small bowel obstruction. Analysis of the CT findings allowed a correct diagnosis.
Ethical issues in teleradiology.
Authors: Ashcroft R E , Goddard P R
Published: June 2014

Teleradiology is the electronic transmission of radiographic images from one geographic location to another for the purposes of diagnosis and/or consultation. It raises interesting ethical and practical issues which have received relatively little attention in the radiology or ethics literature to date. These include confidentiality, data security and technological reliability, consent, competence, interprofessional and professional-patient relationships, and the organization of medical services. This paper reviews these issues, discussing how far these are new concerns in radiological practice, and makes suggestions for minimum ethical and professional standards for teleradiological practice.
Thyroid dosimetry in Europe following the Chernobyl accident.
Authors: O'Hare N J , Murphy D , Malone J F
Published: June 2014

Thyroid dose estimates for European populations following the Chernobyl accident in 1986 have been presented in the literature. These dose estimates used standard values for parameters such as thyroid mass, iodine uptake and biological half-life. Previous work has shown that these values are not representative of European populations and that local values should be utilized. Using published data on revised thyroid dose estimates, thyroid dosimetry data arising as a result of the Chernobyl accident are presented for 22 European countries. When these are compared with previously published estimates it is found that in all cases the previous results underestimate the thyroid dose by up to a factor of 4. Risk estimates on the incidence of fatal and non-fatal thyroid cancers are also determined from this new data and, again, the results are underestimated. The results show an increase in the number of fatal cancers, rising from 149 as predicted by the NEA to 310 under the new estimates, and from 180 as predicted by UNSCEAR to the new estimate of 380.
Experimental determination of practical peak voltage.
Authors: Baorong Y , Kramer H M , Selbach H J , Lange B
Published: June 2014

In diagnostic radiology the practical peak voltage was initially derived by postulating that, for a given combination of X-ray tube and contrast geometry, a constant X-ray tube voltage should produce the same low level contrast as an arbitrarily pulsating X-ray tube voltage. It has been shown previously that the practical peak voltage can be properly defined as a weighted average of the X-ray tube voltage. Up to now the concept of practical peak voltage was based entirely on the results of calculations. The present paper describes the experimental investigations for measuring and comparing the contrast-equivalent X-ray tube voltage and practical peak voltage derived from an invasive measurement of the time-dependent X-ray tube voltage. Within the experimental uncertainties, the results demonstrate the mutual equivalence of the practical peak voltage and the contrast-equivalent X-ray tube voltage.
Relationships between age, mammographic features and pathological tumour characteristics in non-palpable breast cancer.
Authors: Ferranti C , Coopmans de Yoldi G , Biganzoli E , Bergonzi S , Mariani L , Scaperrotta G , Marchesini M
Published: June 2014

Non-palpable breast cancers are often in situ or smaller and have less nodal and distant metastases than palpable lesions. They represent a heterogeneous group of tumours, which may have different prognostic behaviour. We analysed a retrospective series of 982 non-palpable breast cancers assessed histologically at the National Cancer Institute of Milan from 1985 to 1995, following pre-operative mammography-guided localization. The association between mammographic data (parenchymal pattern and findings), patient age and tumour histology was investigated by review of clinical records and statistical modelling. We also investigated the association between the presence or absence of microcalcification as a mammographic finding and pathological tumour characteristics (tumour size, axillary nodes status and grading) or receptor status for oestrogen (ER) and progesterone (PgR). In situ disease or invasive tumour with an intraductal component, whether extensive or not, were commoner in young women and mammography more frequently showed a dense parenchymal pattern and microcalcifications in these cases. In older women (55 years or more), a fatty breast pattern, nodular opacities with or without microcalcifications, and invasive tumours of the ductal, lobular, mixed or other types were closely related. When the relationships between mammographic findings, pathological tumour characteristics and receptor status were investigated for invasive cancers, there was an association between the presence of microcalcifications and less favourable tumour characteristics.
Predictive value of galactographic patterns for benign and malignant neoplasms of the breast in patients with nipple discharge.
Authors: Dinkel H P , Trusen A , Gassel A M , Rominger M , Lourens S , Müller T , Tschammler A
Published: June 2014

The purpose was to identify features of malignant and non-malignant neoplastic breast disease on galactography and to estimate their predictive value. This is the largest reported study correlating galactographic morphological patterns with histopathology and the only blinded study. The study included 351 consecutive galactograms and 161 breast biopsies performed in patients with nipple discharge over a 10-year period. Three radiologists, blinded to clinical data and histological results, re-evaluated 158 previously performed galactograms of patients who had undergone excision biopsy. Extravasation or incomplete filling precluded reading in 9.5% of examinations. Among the remaining 143 examinations there were 11 cancers (7.7%), 56 papillomas (39.2%), 19 cases of intraductal papillomatous proliferation (13.3%), 55 cases of fibrocystic or secretory disease (38.5%) and two normals. A "filling defect/cut-off" pattern (n = 90) was found in 6 cancers (6.7%) and 58 cases of papilloma or papillomatous proliferation (64.4%). A "leafless tree" pattern was found only in benign cases (n = 12; 8.4%). In 32 of 143 cases (22.4%) a "ductal ectasia" pattern was present, in one case of which (3.1%) cancer was found. Cancer was identified in two of four cases with an "architectural distortion" pattern. Cancer is rare in patients with nipple discharge. A tendency towards a lower incidence of cancer associated with the "ductal ectasia" and "leafless tree" patterns was found. No statistical evidence was found to indicate that galactography provides an effective prospective diagnosis of malignancy. However, an abnormal galactogram strongly correlated (p < 0.001) with the presence of a breast neoplasm when both benign and malignant tumours were considered. The most important role played by galactography is in the localization of breast neoplasms and in the choice of appropriate surgical therapy.
Effect of Paget's disease of bone on areal lumbar spine bone mineral density measured by DXA, and density of cortical and trabecular bone measured by quantitative CT.
Authors: Cherian R A , Haddaway M J , Davie M W , McCall I W , Cassar-Pullicino V N
Published: June 2014

Although bone density may be increased in bone that is affected by Paget's disease, density changes in cortical and trabecular bone and the effect on bone that is apparently unaffected by Paget's disease are relatively unexplored. We have investigated 81 vertebrae (28 affected, 53 unaffected) in 27 patients with Paget's disease, by dual X-ray absorptiometry (DXA) and by quantitative CT (QCT) bone density measurements of trabecular and cortical bone. DXA bone density was high (mean z-score = 1.62, p < 0.001) in vertebrae affected by Paget's disease, but not significantly different from normal in unaffected vertebrae (mean z-score = 0.07, ns). Mean QCT z-score in Paget's vertebrae was 2.07 (p = 0.009) for cortical bone and 1.37 (p = 0.008) for trabecular bone. DXA correlated with QCT cortical values in affected and unaffected bone (r = 0.8 and 0.56, respectively), and with QCT trabecular values (r = 0.72 and 0.48, respectively). There was no significant difference in the slopes for the correlations in affected or unaffected bone. Cortical QCT values are underestimated in Paget's disease compared with physical measurements of density, owing to the computer algorithm used. High DXA values may alert to the possibility of Paget's disease, especially if the value deviates from the expected normal sequence in lumbar vertebrae. Osteoporotic vertebrae may be overlooked if the average value of bone mineral density is taken in the lumbar spine without reviewing each vertebra.
Dose-area product measurements in a range of common orthopaedic procedures and their possible use in establishing local diagnostic reference levels.
Authors: Crawley M T , Rogers A T
Published: June 2014

There is a national drive towards establishing reference doses for radiological procedures with the aim of optimizing patient doses. Furthermore, the establishment of diagnostic reference level doses became a legal requirement for all hospitals on 13 May 2000. However, to date there are little published data on patient radiation doses from fluoroscopic procedures during orthopaedic surgery. Data relating to patient dose for 492 patients undergoing fluoroscopic examinations during a range of surgical orthopaedic procedures in 1997-1998 have been analysed. Median dose-area product (DAP) readings and interquartile ranges for a variety of common fluoroscopic orthopaedic procedures are presented. In general, the median DAP for procedures on limbs and extremities was quite low (0.04-1.62 Gy cm2), with screening times in the range 0.2-2.0 min, whilst for procedures involving the hips and spine the median DAP was considerably higher (0.4-10.2 Gy cm2), although overall screening times were similar, in the range 0.2-1.4 min. Approximate effective doses have been estimated. For procedures involving the limbs and extremities, the effective dose was generally less than 10 microSv, and for procedures involving the hips and spine it was found that the effective dose could rise to about 1 mSv. Collective doses for each procedure have been calculated to inform prioritization of procedures for local dose reduction strategies.
Absorbed dose and deterministic effects to patients from interventional neuroradiology.
Authors: Mooney R B , McKinstry C S , Kamel H A
Published: June 2014

Following the presentation of radiation-induced skin effects by three patients who had undergone glue embolisation of intracranial arteriovenous malformation (AVM), measurements were made of absorbed dose to the skin of patients undergoing other interventional neuroradiological procedures that involve long fluoroscopy times. The maximum absorbed dose to the skin measured by thermoluminescent dosemeters during these procedures was 4 Gy. From these measurements and from records of fluoroscopy time and the number of digital runs acquired, estimates of the maximum absorbed skin dose were made for the AVM patients. The best estimate of maximum absorbed dose to the skin received by any of the AVM patients during a procedure was 5 Gy, which is consistent with the skin effects presented by the AVM patients, that is temporary epilation and main erythema. Maximum absorbed dose to the skull was estimated to be 45 Gy and to the outer table of the skull 55 Gy. Although it is unlikely that the AVM patients will suffer serious effects from these skin doses, there remains some uncertainty over the risk of long-term effects to the skull. Examination of the fluoroscopy unit showed that the image intensifier was not performing optimally in terms of entrance dose rate and resolution. Replacement of the unit with modern X-ray equipment designed for interventional radiology was prioritized. Operators should be aware of the potential risks to patients from complex interventional neuroradiology procedures and should optimize their procedures to minimize such risks. Patients undergoing prolonged and complex procedures should be counselled regarding the symptoms and risks of large doses of radiation.
Patient dose from barium procedures.
Authors: Ruiz-Cruces R , Ruiz F , Pérez-Martínez M , López J , Tort Ausina I , de los Ríos A D
Published: June 2014

The objective of this work was to estimate patient doses (dose-area product, organ dose, effective dose and entrance surface dose) for barium procedures. A total of 175 procedures, in 175 patients, for five different examination categories was analysed. Dose-area product was determined using a transmission ionization chamber. Organ dose and effective dose were assessed using a knowledge of the examination and the software. For all patients, the contribution of fluoroscopy to the total dose was greater than that from radiography. Dose-area product from double contrast barium enema, enteroclysis and intestinal tract procedures was higher than that obtained for the other procedures. The average effective dose was 1.04 mSv and 13.99 mSv for oesophageal tract and enteroclysis examinations, respectively. Entrance surface dose in the oesophageal tract was 16 mGy, 10 times lower than for the other four procedures. Patient dose reduction in barium procedures may be achieved by improved training of resident radiologists, senior radiologists and other specialists in radiation protection.
Percutaneous ethanol injection of the supplying artery to hepatocellular carcinoma that is not amenable to conventional treatment.
Authors: Lin Z Y , Wang J H , Hsieh M Y , Yu M L , Chen S C , Chuang W L , Wang L Y , Tsai J F , Chang W Y
Published: June 2014

The purpose of this study was to evaluate the clinical usefulness of ultrasound-guided percutaneous ethanol injection of the supplying artery (PEISA) to the tumour in the palliative management of hepatocellular carcinoma (HCC) that is not amenable to conventional treatments. A total of 23 cases of HCC, measuring from 3.1 cm to larger than 15 cm (median 5.4 cm) in 17 cirrhotic patients, were treated by PEISA. PEISA was used to control rapid growth of the tumour in seven patients and to reduce abdominal discomfort caused by rapid expansion of the tumour in 10 patients. Tumours with arterial Doppler signals persisting after PEISA underwent repeated treatment. The follow-up period ranged from 2-48 months. PEISA was achieved in 69 out of 76 attempts (90.8%). The amount of ethanol injected on each occasion ranged from 2.5-33 ml. Follow-up colour Doppler scanning showed complete elimination of tumour Doppler signals in 22 out of 23 lesions (95.7%). Following treatment, one tumour disappeared, 13 tumours shrank and nine tumours were unchanged in size. All patients with abdominal discomfort had relief after treatment. The common complications of PEISA were local pain and fever. In conclusion, PEISA is effective at treating painful HCC unsuitable for conventional treatment.
A novel quality assurance method in a university teaching paediatric radiology department.
Authors: Gallet J M , Reed M H , Hlady J
Published: June 2014

Primary diagnostic equipment in a paediatric radiology department must perform at optimal levels at all times. The Children's Hospital Radiology Department in Winnipeg, Canada, has developed an impartial means of reporting radiographic image quality. The main objectives of this study programme were two-fold. First, to monitor diagnostic X-ray equipment performance, and second, to improve the resultant image quality as a means of implementing the fundamental concepts of continuous quality improvement. Reading radiologists completed a quality assurance (QA) card when they identified a radiographic image quality problem. The cards were subsequently collected by the clinical instructor who then informed, in confidence, the radiographers of the written comments or concerns. QA cards have been conspicuously installed in the paediatric radiology reading room since the middle of 1993. Since its inception, equipment malfunction has been monitored and indicators for improving image quality developed. This component of the QA programme has shown itself to be a successful means of communicating with radiographers in maintaining superior image quality.
Vaginal vault brachytherapy: the effect of varying bladder volumes on normal tissue dosimetry.
Authors: Hoskin P J , Vidler K
Published: June 2014

This study was designed to assess the impact of bladder volume on dosimetry to critical normal structures in vaginal vault brachytherapy using a single line source vaginal applicator. 30 consecutive patients undergoing vaginal vault brachytherapy were studied by CT scanning with the applicator in situ and the bladder empty and then with the bladder containing either 35 ml of water (10 patients), 70 ml of water (10 patients) or 100 ml of water (10 patients). The scans were then analysed with isodose distributions overlayed to determine changes in dosimetry. No effect on bladder dose was seen with increasing volume compared with the empty bladder; however, there was a reduction in amount of small bowel within the high dose treatment region as bladder volume increased. With 100 ml bladder volume, the reduction reached 57.5% compared with the empty bladder. We conclude that vaginal vault brachytherapy should be undertaken with a bladder volume of at least 100 ml, which will considerably reduce the amount of small bowel in the irradiation volume with no increase in bladder dose.
A filter for breast imaging on a radiotherapy X-ray simulator.
Authors: Utting J F , Donovan E M , Suter B
Published: June 2014

Simulator radiographs taken as a record of breast radiotherapy planning often show ill defined breast tissue margins because exposure parameters are set to optimize visualization of the chest wall rather than the bulk of the breast. This creates difficulties when using simulator images as reference images in verification by comparing with either portal film or images from an electronic portal imaging device. Our aim was to improve breast images taken at simulation without changing exposure parameters that have been optimized for visualization of the chest wall. This has been achieved via an external filter to be used when taking radiographs with the treatment simulator. The filter is made of stainless steel coated with tin and is shaped to maintain acceptable imaging of the chest wall by covering only the section of field anterior to the chest wall. Radiographs of breast simulations using the filter have been accepted as satisfactory by both clinicians and radiographers. The filter is now in routine clinical use for breast and chest wall treatment simulation.
MRI of retroperitoneal collections: a comparison with CT.
Authors: Negus S , Sidhu P S
Published: June 2014

Retroperitoneal collections in the absence of pancreatitis are rare. Imaging plays an important role in determining the aetiology of these collections and in allowing percutaneous drainage to be performed safely. A review of the imaging characteristics on both CT and MRI is presented, highlighting the advantages and disadvantages of these two modalities and their complimentary roles.
Radiation dosimetry using polymer gels: methods and applications.
Authors: McJury M , Oldham M , Cosgrove V P , Murphy P S , Doran S , Leach M O , Webb S
Published: June 2014

New, complex radiotherapy delivery techniques require dosimeters that are able to measure complex three-dimensional dose distributions accurately and with good spatial resolution. Polymer gel is an emerging new dosimeter being applied to these challenges. The aim of this review is to present a practical overview of polymer gel dosimetry, including gel manufacture, imaging, calibration and application to radiotherapy verification. The dosimeters consist of a gel matrix within which is suspended a solution of acrylic molecules. These molecules polymerize upon exposure to radiation, with the degree of polymerization being proportional to absorbed dose. The polymer distribution can be measured in two or three dimensions using MRI or optical tomography and, after calibration, the images can be converted into radiation dose distributions. Manufacture of the gel is reported to be reproducible, and measured dose in the range 0-10 Gy is accurate to within 3-5%. In-plane image resolution of 1 mm x 1 mm, with image slice thicknesses of between 2-5 mm, is typically achievable using clinical 1.5 T MR scanners and standard T2 weighted imaging sequences. The gels have been used to verify a number of conventional and novel radiotherapy modalities, including brachytherapy, intensity modulated radiotherapy and stereotactic radiosurgery. All the studies have confirmed the value and versatility of the dosimetry technique.
Is the appearance of microcalcifications on mammography useful in predicting histological grade of malignancy in ductal cancer in situ?
Authors: Dinkel H P , Gassel A M , Tschammler A
Published: June 2014

It has been proposed that the grade of malignancy of ductal carcinoma in situ (DCIS) of the breast can be estimated by the morphology of microcalcifications found on mammography. We correlated microcalcifications and histopathology in a retrospective blinded review. We reviewed all patients who underwent excisional breast biopsy over a 5 1/2-year period. Mammograms and pathology slides of all patients (n = 49) with DCIS of the breast were included in a blinded retrospective analysis. Mammographic microcalcifications were divided into four categories, "linear branching", "coarse granular", "fine granular" or "no microcalcification". Independently, pathology specimens were assigned to poorly, intermediately and well differentiated categories according to the consensus classification of DCIS introduced by the European Organisation for the Research and Treatment of Cancer. Two patients had no microcalcifications. 25 (53%) of the remaining 47 patients had "linear branching" microcalcifications, 10 (21%) had "coarse granular" and 12 (25.5%) had "fine granular" microcalcifications. 19 patients (40%) had poorly differentiated, 23 (49%) intermediately differentiated and 5 (11%) well differentiated subtypes of DCIS. 14 (56%) of the 25 patients with "linear branching" microcalcifications had poorly differentiated DCIS, 10 (40%) had intermediately differentiated and 1 (4%) had well differentiated DCIS. 3 (30%) of 10 patients with "coarse granular" microcalcifications had poorly differentiated DCIS, 5 (50%) had intermediately differentiated and 2 (20%) had well differentiated DCIS. 2 (17%) of 12 patients with "fine granular" microcalcifications had poorly differentiated DCIS, 8 (67%) had intermediately differentiated and 2 (17%) had well differentiated DCIS. These findings were not statistically significant. In conclusion, "linear branching" microcalcifications tended to be associated with higher pathological grading. However, correlation was poor and there was considerable overlap between categories. Histological type of DCIS cannot be predicted prospectively on mammographic appearances.
Adynamic ileus after caesarean section mimicking intestinal obstruction: findings on abdominal radiographs.
Authors: Kammen B F , Levine M S , Rubesin S E , Laufer I
Published: June 2014

The purpose of this study was to determine the spectrum of findings and the frequency of apparent distal colonic obstruction on abdominal radiographs in women with obstructive symptoms following Caesarean section. A search of radiology files yielded 21 patients who had abdominal radiographs because of obstructive symptoms during the early post-operative period. The radiographs were reviewed retrospectively to characterize the bowel gas patterns in these patients. Medical records were also reviewed to determine the treatment and patient course. Abdominal radiographs showed findings suggestive of distal colonic obstruction in 15 patients (71%), small bowel obstruction in 2 (10%), adynamic ileus in 3 (14%) and a normal bowel gas pattern in 1 (5%). In all 15 patients with apparent distal colonic obstruction, there was minimal or no gas in the rectosigmoid, with an associated pelvic mass representing the enlarged post-partum uterus, which compressed the rectosigmoid and prevented it from filling with gas. All 21 patients had rapid clinical or radiographic improvement on conservative management, indicating a transient post-operative ileus. Radiologists should be aware of the limitations of abdominal plain radiographs following Caesarean section so that a post-operative ileus is not mistaken for a distal colonic obstruction and conservative measures can be undertaken to decompress the bowel until the ileus resolves.