bluuebunny/crossref_metadata_2025_split huggingface dataset:
Compensation for field non-uniformity on a mammographic X-ray unit
Authors: Cowen A R , Brettle D S , Workman A 
Published: July 2009

A well observed phenomenon in diagnostic radiology is that of the anode heel effect. The heel effect is caused by target absorption of X rays emitted from an electron impact site at angles more nearly parallel to the anode face (Curry et al, 1984). This has the consequence of producing a non-uniform exposure profile in the image plane (Figure 1). Other non-uniformities may be caused by imperfections in any pre-filtration foils (IPSM, 1989).
Although non-uniformity is tolerated and to a large extent is of no clinical concern, there are applications where a uniform field exposure is required. One such area is where quantitative measurements need to be made at different spatial positions. Additionally it may prove advantageous to use a flat field exposure in mammographic examination of women with very large breasts where areas towards the breast periphery may get a significantly lower exposure than at the chest wall, reducing image contrast in that region.
As part of a Department of Health evaluation into the use of computed radiography (CR) in mammography (see, for example, Takeno et al, 1987) the authors have been investigating the mammographic imaging performance of CR using quantitative measurement techniques. One such technique is noise power spectrum analysis. Because this technique requires uniform exposure distribution over a large field area (12 cm × 12 cm) it was necessary to develop a technique to compensate for X-ray beam non-uniformity on a clinical mammography unit (Philips Diagnost UC).
Use of ultrasound in osteomyelitis
Authors: Nath A K , Sethu A U 
Published: July 2009

We were pleased to read the points raised by Dr Derek Roebuck and we fully appreciate his conclusion in the last paragraph. However, we wish to make the following comments:
1. In the conclusion of our paper we have also suggested use of ultrasound in screening of all patients who are clinically suspected of having osteomyelitis.
Clinical experience with electron pseudoarc therapy
Authors: McKenzie M R , Freeman C R , Pla M , Guerra J , Souhami L , Pla C , Podgorsak E B 
Published: July 2009

Abstract
Between November 1986 and June 1990, 24 patients were treated with electron pseudoarc therapy at McGill University. There were 21 females and three males aged 27 to 81 years (median 62 years). 17 patients, nine of whom had received previous conventional locoregional irradiation, were treated palliatively for locally extensive breast carcinoma. Eight of these 17 patients achieved a complete, and six a partial, response to treatment; nine subsequently developed evidence of progressive disease within the treatment field after intervals of one to 27 months (median 5 months) following therapy. Eight patients developed moist desquamation of the treated chest wall, which was extensive in four; one of these patients developed chronic ulceration of the skin. The latter and one additional patient developed radiation pneumonitis. Seven patients were treated with radical intent, two following mastectomy for breast carcinoma, and one each for chest wall lymphoma, chest wall sarcoma, scalp angiosarcoma, scalp lymphoma and posterior cervical soft tissue sarcoma. Local control was achieved in six of these seven patients with minimal toxicity. Electron pseudoarc therapy is a treatment option for selected breast carcinoma patients for palliation of extensive chest wall disease, although morbidity may be considerable. The technique may, however, play a more useful role in other situations where the superficial portion of large curved surfaces is to be treated with curative intent.
Fatal pulmonary Kaposi's sarcoma and Castleman's disease in a renal transplant recipient
Authors: Mandel C , Silberstein M , Hennessy O 
Published: July 2009

AbstractTwo unusual complications of immunosuppression, Castleman's disease and Kaposi's sarcoma, occurring in a renal transplant recipient, are reported. Kaposi's sarcoma is a potentially curable condition in immunosuppressed patients if recognized and treated appropriately. In this patient, the pulmonary Kaposi's sarcoma was not diagnosed and this lead to the patient's death.
Haemothorax in hereditary multiple exostosis
Authors: Castells L , Comas P , González A , Vargas V , Guardia J , Gifré L 
Published: July 2009

Hereditary multiple exostosis (HME) or diaphysial aclasis is an autosomal dominant condition characterized by multiple exostoses which appear in different parts of the skeleton (Solomon, 1963). Lesions occur in infants and children and usually cease to enlarge at puberty. Complications are uncommon, and haemothorax has occasionally been described (Balatskii et al, 1973; Proper et al, 1980; Tejeira et al, 1989). We report a patient presenting with spontaneous haemothorax as a complication of costal exostoses.
A 19-year-old boy known to have multiple exostoses was admitted with sudden pleuritic right-sided pain. There was no history of recent trauma. On examination he was apyrexial and blood pressure was normal. He had pain in the right side of his chest and shortness of breath and there was dullness to percussion and reducedbreath sounds at the right base.
Spinal bone density measured with a 5 s scan
Authors: Buxton F M A , Blake G M , Parker J C , Lewis M K , Fogelman I 
Published: July 2009

Absorptiometry provides a convenient, non-invasive method of measuring bone mass in the skeleton with high precision and low radiation dose to the patient (Tothill, 1989). Dual photon absorptiometry (DPA) based on the radionuclide source 153Gd was developed for measuring bone mineral density (BMD) at the clinically important sites of the spine and the hip (Wilson & Madsen, 1977). Recently, dual X-ray absorptiometry (DXA) has superseded DPA (Cullum et al, 1989). Compared with DPA, DXA has advantages of improved precision (coefficient of variation of 1% for spinal DXA compared with 2–3% for DPA) and shorter scanning times (6–8 min for DXA compared with 20–30 min for DPA) (Sorenson et al, 1989). Use of an X-ray tube instead of a radionuclide eliminates the problems associated with radioactive decay of the source (Lindsay et al, 1987).
In the most recent development in DXA technology at least two manufacturers have introduced scanners based on a fan beam configuration coupled to a multidetector scanning head (Pommet et al, 1991; Steiger et al, 1991). Compared with the conventional configuration of a pencil X-ray beam linked to a single detector, scanning times are considerably shortened. In the instrument used for the study described in this report, the Hologic QDR-2000, fan beam scans of the lumbar spine (L1–L4) can be performed in either 1 min (sampling 5 lines cm−1 or 2 min (sampling 10 lines cm−1) depending on the precision required.
Oesophageal varices: how reliable is a barium swallow?
Authors: Ginai A Z , Van Buuren H R , Hop W C J , Schalm S W 
Published: July 2009

Abstract
Although barium swallow is a quick and easy method for diagnosing oesophageal varices, there is considerable variation between observers because objective quantitative radiological criteria have so far not been defined. In order to define these criteria, a blind radiological/endoscopic comparative study using endoscopy as the gold standard was retrospectively carried out in 72 patients. A prospective study was then carried out in 47 patients to define the validity of the radiological criteria found by the first study. The results of both studies showed that the length and the width of the mucosal folds representing varices as measured on barium swallow radiographs have a significant relationship with the grade of the varices as determined by endoscopy. We conclude that barium swallow is a quick and reliable method for quantitative assessment of oesophageal varices.
Paediatric radiotherapy—the avoidance of late radiation damage to the growing hip
Authors: Irwin C J R , Thomson E , Plowman P N 
Published: July 2009

Epiphyseal plates of growing bones are sensitive to ionizing radiation and this poses problems for the paediatric radiotherapist.
The late abnormalities of spinal growth following radiotherapy are well documented in the literature (Rubin & Casarett, 1968; Probert et al, 1973; Probert & Parker, 1975). However, the proximal femoral and acetabular epiphyses are so close to many pelvic and inguinal/thigh portals and the consequences of abnormal hip development are so important, that this particular joint justifies closer scrutiny. Slipped capital femoral epiphysis following radiotherapy and chemotherapy (Dickerman et al 1979; Libshitz & Edeiken, 1981) and avascular necrosis of the femoral head (Timothy et al, 1978) have been described following high doses of radiotherapy to this region.
In this manuscript we describe a child in whom electron beam therapy to the groin delivered only low dose radiation to the proximal hip epiphyses—130 cGy fractionated over 5 weeks—but who suffered late maldevelopment.
We explore the success of various radiotherapy techniques in minimizing the dose to the hip epiphyses in four other children treated subsequently in this department. The appropriate positioning of the limb, the choice of treatment modality and, where possible, individual shielding blocks are considered and their effect on the dose to the hip estimated. Absorbed doses of radiation delivered to the midpoint of the proximal femoral epiphyses have been retrospectively determined.
In August 1983, an 8-month-old boy presented with short history of a lump in the left testis.
The ultrasound markers of chromosomal disease: a retrospective study
Authors: Twining P , Zuccollo J 
Published: July 2009

Abstract
Over a 3 year period 37 pregnancies were complicated by a chromosomal abnormality. In the two cases of trisomy 13, holoprosencephaly, facial clefting, polydactyly and growth retardation were seen. In the seven cases of trisomy 18, abnormalities of the extremities, face and heart were common. Growth retardation and diaphragmatic hernia were also demonstrated. In the 21 cases of Down's syndrome the main abnormalities were cardiac, duodenal atresia and subtle digital anomalies. The two fetuses with triploidy showed a large hydropic placenta and holoprosencephaly respectively, and all five cases of Turner's syndrome demonstrated a cystic hygroma two of which were associated with hydrops. From the antenatal scans major anomalies were detected in 18 fetuses, however, chromosomal disease was suspected in only 15 cases. This was in part owing to a high false negative rate for cardiac anomalies (14 cases) in both routine and detailed scans. Owing to the diversity of anomalies present in chromosomal disease full assessment of the fetus is recommended with particular attention to the fetal heart, face, hands and feet. Specific anomalies are suggested for karyotype.
Abdominal MRI using a negative contrast agent
Authors: Bach-Gansmo T , Dupas B , Gayet-Delacroix M , Lambrechts M 
Published: July 2009

Abstract
A dose of 0.5 g of a negative oral contrast agent for labelling the bowel, was given to 40 patients in a clinical trial. Oral magnetic particles (OMP) consist of crystals of iron oxide with superparamagnetic properties, and are administered in 800 ml of a viscous suspension in order to obtain a uniform distribution. The aim of the study was to identify any adverse effects up to 1 week following ingestion, as well as the contrast distribution and effect, together with the induction of artifacts. A comparison of diagnostic value of the pre and postcontrast ingestion series was also performed. Vomiting followed ingestion in a single patient already nauseated and was the only adverse effect. Good contrast distribution and effect with no artifacts were present. The diagnostic information was greatly improved after OMP ingestion, and the diagnosis would not have been possible without the use of the contrast agent in 41% of the examinations.
Patient doses received during digital subtraction angiography
Authors: Steele H R , Temperton D H 
Published: July 2009

Digital subtraction angiography (DSA) is based on digital image processing with logarithmic subtraction and edge enhancement. It is used increasingly for the visualization of blood vessels throughout the body. The bulk of the workload in the angiography suite at the Queen Elizabeth Hospital, Birmingham involves carotid and femoral angiograms with other examinations, including hepatic and renal angiograms, being carried out less frequently.
A typical DSA examination involves both fluoroscopy and DSA images taken at different projections and at different regions of the body. The exposure factors are selected automatically and the ease of image acquisition facilitates the acquisition of large numbers of images—exceeding 100 for some studies. Some examinations, but predominantly femoral angiograms, also involve the use of Puck serial films with the exposure factors being selected manually.
The screening time, number of DSA or Puck images and the exact projection and exposure factors used varies between patients. The dose to different patients varies enormously and, as with all medical radiation exposure, should be clinically justified. Taylor et al (1989) measured the entrance absorbed dose for a posteroanterior (PA) projection using a Rando anthropomorphic phantom and concluded that radiation doses to patients undergoing DSA examinations are amongst the highest for any X-ray procedure. The patient dose is increased because DSA images are taken using low voltages (e.g. 60–70 kVp) if technically possible in order to maximize image contrast.
An alternative approach to stenting the obstructed ureter
Authors: D'Souza R , Tait P , Thomson R W , Trewhella M 
Published: July 2009

Ureteric stenting allows palliative treatment of strictures resulting from trauma, surgery, neoplasm or from scarring following treatment of malignancy. Retrograde and antegrade approaches can be used (Mitty et al, 1986; Shore et al, 1987) but, in a small proportion of patients, neither approach is successful, and patients with ureters which are completely occluded present a problem. We describe a combined antegrade and retrograde technique analogous to that used in biliary stenting (Robertson et al, 1987; Freeman et al, 1991) as a useful method in such cases. Three cases are described which illustrate the salient features.A 56-year-old man was admitted for insertion of a stent across an obstructed right distal ureteric orifice. His well-differentiated bladder tumour had been treated by several endoscopic resections over the previous 5 years and one course of intravesical chemotherapy had been given 16 months earlier.
The transabdominal ultrasound appearances of a colovesical fistula
Authors: Long M A , Boultbee J E 
Published: July 2009

Abstract
When the clinical manifestations of colovesical fistulae lack diagnostic features, significant diagnostic delay may result. The literature contains conflicting recommendations regarding the optimal method of imaging such fistulae. We describe the transabdominal ultrasound appearances of a colovesical fistula and review the relevant literature. The identification of the ureteric orifices with their associated urinary jets and the use of abdominal compression are essential components of the technique.
Variation in lumbar spine and femoral neck bone mineral measured by dual energy X-ray absorption: a study of 329 normal women
Authors: Truscott J G , Oldroyd B , Simpson M , Stewart S P , Westmacott C F , Milner R , Horsman A , Smith M A 
Published: July 2009

AbstractReference ranges used in dual energy X-ray absorptiometry (DXA) have previously used piecewise linear fits to the whole data set for spine or femur bone mineral density (BMD) as a function of age. In a study of 329 Caucasian normal women we present a refinement to the normal range by fitting straight lines between quinquennial mean values of BMD for each site measured (lumbar spine, femoral neck and Ward's triangle). From the age of 40 years onwards the premenopausal women demonstrated minimal loss of BMD whereas postmenopausal women showed a rapid loss amounting to 27% in the lumbar spine, 27% in the femoral neck and 38% in the Ward's triangle region in the age range under examination. Comparison of quinquennial means for pre and postmenopausal women in age bands 45–49 years and 50–54 years shows that at these ages postmenopausal BMD is significantly lower than premenopausal BMD (P &lt; 0.05). This finding suggests that separate normal ranges should be used for pre and postmenopausal women. As reduction in the production of oestrogen is a major factor in postmenopausal bone loss and oestrogen function is related to years since menopause (YSM), a more logical way of displaying postmenopausal normal BMD ranges would be in terms of YSM rather than chronological age. Such data are given in this paper.
A halo-ring technique for fractionated stereotactic radiotherapy
Authors: Clark B G , Podgorsak E B , Souhami L , Olivier A , Sixel K E , Caron J-L 
Published: July 2009

Abstract
Stereotactic radiosurgery has become established as an effective treatment modality for certain non-malignant brain diseases such as arteriovenous malformations. This paper describes an extension of our linear accelerator-based radiosurgical technique to fractionated treatment of intracranial disease. The fractionated stereotactic radiotherapy technique expands the use of the modality by sparing normal cells within the treatment volume thus improving the therapeutic ratio. The first treatment is given using a stereotactic frame both for target localization and patient immobilization. The frame is then removed and subsequent treatments use a standard neurosurgical halo-ring for patient immobilization. The halo-ring is left in place on the skull for the duration of the course of treatment. Thus the physical requirements for fractionation pertain firstly to the patient immobilization and target localization using the halo-ring and secondly to the stringent quality assurance procedures required to maintain spatial accuracy under these new conditions. We describe a sensitive and effective technique for checking the rotational beam parameters and collimator alignment which we use immediately prior to treatment to ensure adequate accuracy of dose delivery to the target volume.
Nasopharyngeal carcinoma: local control by megavoltage irradiation
Authors: Lee A W M , Law S C K , Foo W , Poon Y F , Chan D K K , S K O  , Tung S Y , Cheung F K , Thaw M , Ho J H C 
Published: July 2009

Abstract
This is a retrospective analysis of the long-term local control in 4128 patients with non-disseminated nasopharyngeal carcinoma treated solely by megavoltage irradiation during the years 1976–1985. The T-stage distribution according to Ho's classification was Tl 37%, T2 14% and T3 49%. Different fractionation schedules had been employed at different periods, and the median dose to the primary target was equivalent to 65 Gy by time dose fractionation calculation. In 8% (344) of patients the tumour failed to regress completely after the basic course, but 89% (148/167) of those suitable for salvage with additional irradiation eventually attained complete local remission. The cumulative incidence of local failure was 24% (5% persistence, 19% recurrence). The 10-year actuarial local failure-free survival was 67%. While patients with T2 and T3a tumours achieved local control comparable to Tl, those with T3c-d had the poorest control (with highest incidence of persistence and advanced recurrence). T-stage adjusted analyses suggested a significant trend of dose-response: the odds ratios for local failure were 1.16 and 1.86, respectively, when patients given 60–63 Gy and 55–59 Gy were compared with those given 64 Gy or above (p value = 0.0018). Patients treated during 1981–1985 achieved higher local failure-free survival than those treated during 1976–1980 (75% versus 70% at 5 years, p value = 0.0013). The possible attributes are studied, and ways for future optimization of treatment discussed.
The ultrasound appearances of pelvic venous collaterals in deep vein thrombosis
Authors: Millar J 
Published: July 2009

Abstract
The ultrasound and Doppler appearances of pelvic venous collaterals in a patient with bilateral ilio-femoral deep vein thromboses are presented. Possible mechanisms for their occurrence are discussed. The importance of these appearances are emphasized in view of their similarity to pelvic varices.
Imaging of a bilobed gallbladder
Authors: Martinoli C , Derchi L E , Pastorino C , Cittadini G 
Published: July 2009

Abstract
Imaging of the gallbladder demonstrates a wide range of anatomical variants, including anomalies in location, number and shape. Duplication anomalies are quite rare and are characterized by a large variety of configurations depending on the size and degree of fusion of the two lobes, and on the number and disposition of the cystic ducts. We present a case of a deeply cleft, bilobed gallbladder imaged by computed tomography (CT), ultrasonography (US) and oral cholecystography (OCG). The anomaly consisted of complete duplication of the body and fundus into two distinct and separated lobes both of which entered a single infundibulum. Awareness of congenital gallbladder variants may help in recognizing and correctly classifying gallbladder abnormalities, thus preventing misdiagnoses.
The effects of radiographic contrast media on leucocyte orientation
Authors: Roobottom C A , Farrow R , Wells I P , Hurlock N 
Published: July 2009

Abstract
The effects of radiographic contrast media (RCM) on leucocyte orientation in vitro were studied using a Zigmond chamber. Leucocyte orientation was assessed following exposure of the leucocytes to iotrolan, iohexol, ioxaglate and diatrizoate. The RCM used were diluted to a concentration similar to that obtained in vivo during routine angiography. At this concentration there was a significant reduction in leucocyte orientation for all RCM investigated but the effect was more pronounced in the monomeric than the dimeric RCM. The results may have significance when deciding which radiographic contrast medium to use in selected patients, particularly those who are immunosuppressed or septicaemic.
Gastrointestinal manifestations in the Hallopeau-Siemens variant of recessive dystrophic epidermolysis bullosa
Authors: Wong W L , Entwisle K , Pemberton J 
Published: July 2009

Abstract
Epidermolysis bullosa encompasses a group of rare disorders typified by blister formation following minor trauma to the skin. Gastrointestinal tract involvement may occur in the extremely rare recessive dystrophic variants. The gastrointestinal manifestations present in 25 patients with the Hallopeau-Siemens variant of recessive dystrophic epidermolysis bullosa are reviewed. In the oesophagus both anatomical and motility abnormalities were observed. Features seen included a generally shortened oesophagus, strictures including those resembling webs, hiatus herniae, decreased peristalsis, oesophageal atony and pseudodiverticulum formation. These patients also had faecal impaction.
Changes in the radiation treatment of cancer of the anus in Glasgow
Authors: Jones R D , Symonds R P , Robertson A G , Thomas R 
Published: July 2009

Abstract
The survival and complication rate of two groups of patients with carcinoma of anus were compared. The first group of 20 patients were treated between 1974 and 1983 by double plane implantation using radium or equivalent caesium needles and supplementary external beam radiotherapy to groin nodes if present. The second group of 26 patients were treated between 1984 and 1990 by external beam radiotherapy followed by a jig implant using afterloading iridium needles. 5-year survival was superior in the second group (73% vs. 40%) with a lower incidence of radiation-induced complications.