bluuebunny/crossref_metadata_2025_split huggingface dataset:
Isotope bone scans in patients with painful knee replacements: do they alter management?
Authors: Owen R J T , Harper W M , Finlay D B , Belton I P 
Published: July 2009

Abstract
A retrospective review of the scintigraphic appearances, clinical findings and outcome in 12 patients presenting with painful knee replacements was made. Three patients required revision surgery; symptoms in the remaining nine patients settled without operative management. Three examinations failed to identify prostheses proven to be infected by aspiration and four were falsely positive for infection without supportive clinical evidence. Four examinations demonstrated loosening and in one patient the bone scan was normal but the prostheses was loose at revision surgery. There were no specific features to predict which prostheses required surgical revision and the ability to diagnose or exclude infection was limited. It is concluded that the results of three phase 99Tcm bone scans in symptomatic knee prostheses are of little assistance in guiding clinical management and that a period of conservative management should be considered prior to operative intervention.
Measurement of collapse cavitation in ultrasound fields
Authors: Digby M , Duck F A , Lenz E J , Price G J 
Published: July 2009

Abstract
This note describes a method for the measurement of hydroxyl free radical concentration due to collapse acoustic cavitation in medical ultrasound fields using aqueous terephthalic acid (TA) solution. An enclosed cylindrical chamber with acoustically transparent membranes at either end was used. Control of cavitation activity was achieved by seeding the solution with polystyrene microspheres to provide cavitation centres. Insonation experiments using unseeded TA previously exposed to air gave very variable results, sometimes detecting cavitation activity and at other times detecting nothing, under the same exposure conditions. Introduction of polystyrene microsphere seeds into the TA enabled it to detect reproducibly levels of cavitation activity at least one order of magnitude higher that in unseeded solutions. An experiment using the seeded TA in a standing wave ultrasound field, set up using a brass reflecting plate, demonstrated that the presence of a standing wave inhibited the measured cavitation yield.
Neonatal platyspondylic dwarfism—a new form
Authors: Kozlowski K , John E , Masel J , Muralinath S , Vijayalakshmi G 
Published: July 2009

Abstract
A new type of neonatal bone dysplasia is reported. Unusual radiographic abnormalities (platyspondyly with unique shape of the vertebral bodies, shortening of the long tubular bones without signs of rickets or metaphyseal dysplasia, marked shortening of well-ossified short tubular bones, schneckenbecken-like pelvis with tri-radiate acetabulum, pseudoepiphysis of the right ulna, unusual shape of calcaneus and periarticular calcifications) allow designation of this disorder as a new form of neonatal dwarfism.
The Mackenzie Davidson Memorial Lecture: Detection of small changes to the brain with serial magnetic resonance imaging
Authors: Bydder G M 
Published: July 2009

Abstract
The use of subvoxel registration of serial magnetic resonance images to detect small changes to the brain and its surrounding tissues and fluids is described and the application of this technique to physiological and clinical problems is illustrated. Isotropic T 1 weighted volume images were obtained in normal subjects and patients on two or more occasions (including pre- and post-contrast enhancement). The images were segmented and three-dimensional rigid body translation and rotation were used with sine interpolation to match precisely the images using a X2 test and a minimization routine. Accurately registered images produced in this way, as well as subtraction images derived from them, were used to detect change to the brain. A system of image interpretation based on recognition of changes in tissue or fluid signal intensity as well as site, shape and size is described. Changes in position are analysed using a simple model based on the concept of two plateaux of higher and lower signal intensities and a border zone between them. Small changes due to differences in orientation of the head, as well as inhalation of oxygen, carbon dioxide and carbogen were observed in normal subjects. Changes were also observed in patients with head trauma, an astrocytoma and multiple sclerosis. Differences due to contrast enhancement and treatment were seen. In addition, children showed changes due to growth and development.
High intensity focused ultrasound—potential for cancer treatment
Authors: Hill C R , ter Haar G R 
Published: July 2009

Abstract
The prospect of being able to use “minimally invasive” surgical techniques is of great interest today, particularly for reasons of health economics, patient acceptability and reduced morbidity. High intensity focused ultrasound (HIFU) has long been known to offer the potential of very precise “trackless lesioning” but has only recently, with the advent of high quality methods of medical imaging, become a practicable possibility. High intensity beams can readily be achieved using either bowl or lens focusing procedures and, by choice of a suitable acoustic frequency, regions of tissue destruction—“lesions”—can be induced at depths of up to at least 10 cm with exposure times of the order of 1 s. Theoretical and experimental evidence indicates that the primary mechanism of damage is thermal, i.e. “cooking” of the tissues. Both conventional cavitation and boiling of tissue water may complicate the situation. Furthermore, substantial non-linear behaviour is involved. On histological appearance the lesions have a spatially sharp demarcation between regions of normal and dead cells. When attempts are made to ablate a block of tissue, by creating an array of adjacent elementary lesions, a phenomenon is observed of inhibition of formation of a lesion whose placing is too close to that of a neighbour. Provided that this problem is dealt with, complete ablation of an extended block of tissue can be achieved. For animal tumours in particular, this observation is reinforced by evidence both of in vitro cell survival and of tumour growth delay experiments. Clinically, the sites accessible for HIFU treatment will be limited by the need for a suitably wide acoustic window that either is available naturally or can be provided by a relatively minor surgical procedure. Tumour sites which thus offer a realistic prospect for local control (and some of which are already the subject of phase 1 trials) include liver, bladder, kidney, prostate, breast and brain. There is also considerable interest in non-cancer applications in these and other sites.
Three-dimensional MP-RAGE—an alternative to conventional three-dimensional FLASH sequences for the diagnosis of viscerocranial tumours?
Authors: Held P , Fellner C , Fellner F , Geissler A , Gmeinwieser J 
Published: July 2009

Abstract
Imaging with three-dimensional (3D) sequences is a frequently used magnetic resonance (MR) technique in the assessment of ear, nose and throat (ENT) tumours near the skull base. Few reports on the contrast behaviour of 3D magnetization prepared rapid gradient echo (MP-RAGE) sequences and their application in ENT tumours exist in the published literature. This paper discusses whether 3D MP-RAGE is an alternative to conventional 3D gradient echo (3D GE) sequences for the diagnostic evaluation of the visceral cranium. Measurements were performed with a Magnetom SP 63 MR system (Siemens) at 1.5 T. 10 healthy volunteers were examined using 3D FLASH sequences with varied flip angles (90°, 70°, 40°, 20°, 10°) and using 3D MP-RAGE to optimize the signal-to-noise ratio (SNR) of muscle, fat and gland tissue. After this optimization 25 patients with ENT tumours near the skull base were examined with 3D FLASH 40°, 3D MP-RAGE 10° (both before and after application of contrast medium) and with 3D FISP 70° (without contrast medium). SNR and contrast-to-noise ratio (CNR) of tumour, inflammatory disease, brain (white and grey matter), compact bone, fat and muscle were calculated. The advantages of 3D MP-RAGE over 3D FLASH 40° include decreased imaging time with decreased motion artifacts and a relatively high contrast between tumour and surrounding tissues. The tissue contrast yielded by the T1/T2 * weighted 3D gradient echo sequence FISP with a flip angle of 70° was not as good as that yielded by 3D MP-RAGE with and without contrast together. In conclusion a combination of contrast enhanced and unenhanced 3D MP-RAGE sequences is the technique of choice for the examination of ENT tumours near the base of the skull.
Computed tomography and magnetic resonance imaging findings in primitive neuroectodermal tumours in adults
Authors: Pickuth D , Leutloff U 
Published: July 2009

Abstract
Primitive neuroectodermal tumours (PNET) are highly malignant, undifferentiated supratentorial neoplasms arising from germinal matrix cells of the primitive neural tube. PNET occur primarily in young children; they are extremely rare in adults. PNET frequently seed within the central nervous system and may be multicentric at the time of diagnosis. Previous reports of the neuroradiological findings refer solely to PNET in children. We describe the computed tomography (CT) and magnetic resonance imaging (MRI) appearances in five adult patients with pathologically proven PNET. In our series, PNET were mostly seen as rather large, heterogeneous masses with cystic and necrotic areas, intratumoral haemorrhage and focal calcification. The prominent contrast enhancement on both CT and MRI scans reflects the increased vascularity of PNET.
Portal imaging with film-cassette combinations: what film should we use?
Authors: Roberts R 
Published: July 2009

Abstract
A large number of commercially available X-ray films were obtained to assess their suitability for megavoltage radiotherapy portal imaging. The speed (represented by optimum film dose), gamma (γ) and latitude of all these films were determined. Films with high γ values are recommended for clinical use to maximize the low levels of radiation contrast produced by a megavoltage beam.
Estimates of radiation dose to National Health Service workers in Northamptonshire from raised radon levels
Authors: Denman A R , Parkinson S 
Published: July 2009

Abstract
Extensive surveys of the radon levels in hospital premises in Northamptonshire have shown that raised radon levels are present, but are localized to areas as small as a single office. Around 9% of sites are above the workplace action limit, and 1% of sites are over 1000 Bq m−3. In addition, radon levels vary throughout the day, and are usually higher at night. Staff in these areas could receive significant doses, and staff working shifts or at night could be at greater risk. Attempts to estimate staff dose using two methods are reported. It is concluded that, even though only a sample of the radon hot-spots was chosen, the radiation dose received by these staff is greater than the occupational exposure of radiographers, radiologists and other health workers.
Low dose rate and high dose rate intracavitary brachytherapy in a patient with carcinoma of the cervix
Authors: Tan L T , Jones B , Freestone G , Dale R G 
Published: July 2009

Abstract
The role of low dose rate (LDR) intracavitary radiotherapy in the management of carcinoma of the uterine cervix is well established. However, there are selected groups of patients in whom high dose rate (HDR) intracavitary radiotherapy may have particular advantages. A case report of a patient with carcinoma of the cervix who received both LDR and HDR intracavitary radiotherapy is presented. A comparison of the normal tissue doses produced by the two forms of brachytherapy is made. The choice of dose for the HDR treatment was calculated using standard linear quadratic isoeffect equations. The relative clinical merits of LDR and HDR treatments in gynaecological cancer are discussed.
Checking the consistency of sensitometers and film processors in a mammographic screening programme
Authors: Law J 
Published: July 2009

Abstract
Quality control procedures in relation to speed and contrast in X-ray film processors, both in X-ray departments and breast screening centres, are based on the use of film sensitometers. Calibrations of these instruments, or simple checks of their constancy with time, are not readily available. A procedure is described in which a reference sensitometer is compared on a 3-monthly basis with the local sensitometer in seven breast screening centres (13 processors) in a region. This demonstrated long-term stability of speed and contrast in both sensitometers and processors. The results may also be used to compare speed and contrast between processors in centres using film of a single type. Standard deviations for single measurements are estimated to be approximately 1% for step density on a single sensitometer, less than 3% for comparison of two sensitometers, about 6% for comparison of processor speed, and between 4 and 5% for processor contrast.
Merkel cell carcinoma of the skin: imaging and clinical features in 93 cases
Authors: Eftekhari F , Wallace S , Silva E G , Lenzi R 
Published: July 2009

Abstract
Clinical, pathological and imaging data for 93 patients with Merkel cell carcinoma were reviewed. Median survival duration from the date of diagnosis was estimated using the Kaplan-Meier product-limit method. Survival durations of patients with no metastastic disease, with regional lymph node metastasis only and with distant metastases were compared using the Cox-Mantel log-rank test. The median age for patients with Merkel cell carcinoma was 70 years (range 35–91 years). The tumour occurred in 71 men and 22 women. The most common primary site was the head and neck region (64 patients), followed by the extremities (21 patients) and the trunk (10 patients). Median survival duration for the whole group was 33 months (range 2 140 months). Imaging studies of the primary sites were available for 10 patients and of metastatic sites for seven patients. Sonograms of the primary skin lesions showed single or multicentric hypoechoic nodules arising from the dermis and growing into the subcutaneous tissues. CT scans showed single or multiple minimally enhancing soft tissue nodules, in two instances associated with lytic bone erosion. The metastatic lesions were moderately hypoechoic on sonography and target-shaped with or without ring-enhancement on CT. Imaging studies have a limited role in diagnosis of the clinically evident primary skin lesions, but may be helpful in the assessment of the depth of the invasion and are crucial in the evaluation of regional and distant metastatic disease. If regional adenopathy is found then CT of the chest, abdomen and pelvis may be in order.
Appendicular measurements in screening women for low axial bone mineral density
Authors: Martin J C , Reid D M 
Published: July 2009

Abstract
Assessment of bone density at hip, spine, radius and calcaneus can predict fracture risk. This paper examines whether women with low bone mineral density (BMD) at the hip and spine can be identified by radial or calcaneal BMD assessment, thus enabling pre-selection of such women for further investigation. BMD in the lumbar spine (LS), femoral neck (FN), trochanter (FT) and Ward's area (FW) was measured by dual energy X-ray absorptiometry (DEXA). These measurements were compared with total (Qtot), trabecular (Qtrab), subcortical (Qscort) and cortical (Qcort) BMD of the ultradistal radius measured by peripheral quantitative computed tomography (pQCT), and ultrasound attenuation (BUA) and velocity (VOS) at the os calcis. Measurements were performed on 216 penmenopausal women aged between 45 and 55 years who attended a randomized osteoporosis screening programme. Correlations for pQCT and ultrasound with DEXA measurements were, at best, moderate (r = 005–053), being poorest for Qcort and VOS. Similar correlations were found between ultrasound and pQCT measurements (r = OO5–O31). None of the pQCT or ultrasound measurements predicted low DEXA measurements. 50–56% of women in the lowest quartile (QU4) of Qtot, Qtrab, Qscort and BUA were also in QU4 of LS, 45–57% were in QU4 of FT and FW, but only 22–33% were in QU4 of FN. To detect all women with osteopenia at FN or LS using pQCT or ultrasound, almost the entire population would have to be screened. In conclusion, pQCT and os calcis ultrasound measurements cannot successfully predict hip and spine osteopenia and could not be used to pre-select women for DEXA hip and spine assessment.
Early tumour response and treatment toxicity after hyperfractionated radiotherapy in nasopharyngeal carcinoma
Authors: Teo P M L , Kwan W H , Leung S F , Leung W T , Chan A , Choi P , Yu P , Lee W Y , Johnson P 
Published: July 2009

Abstract
The aim of the present study was to undertake a planned interim analysis of a prospective randomized trial comparing the tumour response and the acute and subacute complications of hyperfractionated radiotherapy and conventional radiotherapy in non-metastatic nasopharyngeal carcinoma (NPC). 100 patients with newly diagnosed non-metastatic NPC were randomized to receive either conventional radiotherapy (Arm I) or hyperfractionated radiotherapy (Arm II). Stratification was done according to the T-Stage (modified Ho's T-Stage classification). The biological effective dose (10 Gy) to the primary and the upper cervical lymphatics were 75.0 and 73.1 for Arm I and 84.4 and 77.2 for Arm II, respectively. Hyperfractionated radiotherapy was associated with significant mucositis which is of higher grade than conventional radiotherapy (p = 0 0001), but the duration of mucositis was similar between the two Arms and all study patients completed radiotherapy on schedule without interruption of radiotherapy. Early survival and tumour recurrence rates were comparable between the Arms. The preliminary results indicate that the hyperfractionated radiotherapy has excellent patient compliance in Chinese patients, with acceptable acute and subacute toxicities and the local and regional complete tumour response rates being comparable with conventional radiotherapy. The significance of the time required after start of radiotherapy to achieve a complete tumour response is discussed.
CT and MRI demonstration of hypothalamic and infundibular relapse in childhood acute lymphoblastic leukaemia
Authors: Tsetis D , Bhattacharya J , Cavenagh J , Thakkar C H 
Published: July 2009

Abstract
The central nervous system is affected in up to 10% of patients with acute lymphoblastic leukaemia, usually in the form of leptomeningeal infiltration. Parenchymal spread is rare. We report a case in which CT and MRI demonstrated hypothalamic and infundibular relapse.
Pseudotumoral brain lesion as the presenting feature of sarcoidosis
Authors: Grand S , Hoffmann D , Bost F , Francois-Joubert A , Pasquier B , Le Bas J F 
Published: July 2009

Abstract
Sarcoidosis rarely presents as an intracranial mass lesion. We report the case of a patient presenting a disturbance of cognitive functions in whom CT and MRI demonstrated a large right fronto-temporal mass lesion with contrast enhancement and surrounding marked oedema, highly suggestive of a brain tumour. The diagnosis of neurosarcoidosis was made after stereotactic biopsy of the lesion.
Transmission titles for X-ray mattresses
Authors: Maughan J , Burniston M , Robertson M 
Published: July 2009

Considerable attention has been given to the introduction of carbon fibre components such as table tops in the implementation of a patient dose reduction programme. There appears to have been much less interest in the attenuating properties of the mattresses used.
With the assistance of Medical Technical Officers we have surveyed a range of tables and mattresses used in our hospital. The results were disturbing Figure 1 shows the distribution of table and mattress transmission values.
Embolization for ruptured superior mesenteric artery aneurysms
Authors: Ishii A , Namimoto T , Morishita S , Saitoh R , Oguni T , Makita O , Takahashi M , Tanaka M , Okamoto M , Kaneko Y , Okamura K 
Published: July 2009

Abstract
Superior mesenteric artery (SMA) aneurysms are very uncommon. They are difficult to detect until they rupture and cause hypovolaemic shock. We performed embolization in four cases of aneurysm of branches of the superior mesenteric artery, succeeding in three cases without the need for surgical treatment. In the first case, the aneurysm was excised because of migration of a microcoil into the left hepatic artery. It was not retrieved because sufficient blood flow to the liver was shown on angiography after migration and no ischaemic change of liver was detected on laparotomy. In the second case, the aneurysm arose from the anterior pancreaticoduodenal artery. In the third case, the patient had two SMA aneurysms, one had been resected at surgery, another was revealed on follow-up angiography and embolized with microcoils. The fourth patient had a jejunal artery aneurysm with extravasation; haemostasis was achieved by packing it In all four cases, no major complications were observed in the clinical course after embolization. Microcoils were considered to be the desirable embolic material, in order to prevent post-therapeutic ischaemic change. Embolization should be the treatment of choice for SMA aneurysms, because it is less invasive and takes less time than surgical treatment.
A study of dose reduction using digital luminescence radiography for lateral skull radiography
Authors: Seifert H , Kubale R , Hagen Th , Kramann B , Leetz H-K 
Published: July 2009

Abstract
For lateral skull radiography the minimum required radiation patient exposure to ensure adequate image quality was determined for digital luminescence radiography (DLR) in comparison with a screen film system (speed class 200). Radiographs were produced with a grid technique on conventional X-ray equipment. A real prepared female head including a true fracture above the pars petrosa ossis temporalis was imaged. The tube current–time product (mAs), and thus the surface entrance dose, was varied systematically. Surface entrance dose was measured with TLD-100 rods. Image quality was judged by experienced radiologists according to the criteria: visual resolution, mean optical density, contrast and perceptibility of specific bone structures. Surface entrance dose was reduced from 0.46 to 0.20 mGy by application of DLR instead of speed class 200 screen–film system without loss of diagnostic information in clinical routine. This corresponds to a dose reduction potential of 57% showing a good agreement with the dose reduction potential of 52% obtained in a previous study using the Alderson head phantom.
Dose–area product measurements in paediatric radiography
Authors: McDonald S , Martin C J , Darragh C L , Graham D T 
Published: July 2009

Abstract
The dose–area product (DAP) could provide a useful quantity for monitoring doses for paediatric radiography, because it is a sensitive parameter, which is simple to record. A study of DAP measurements has been carried out for single radiographic projections for paediatric patients and comparisons made with measurements of entrance dose. The technique has been used to investigate doses for examinations performed with and without a grid. There is a linear relationship between DAP and entrance dose, with a variation of ±20% for pelvis, abdomen, spine and skull radiographs, but data for chests are more scattered. Logarithm of the DAP is linearly related to an equivalent patient diameter and reference levels could be set in terms of DAP either by patient age range or size. Effective doses determined from DAPs were 0.1 0.3 mSv for abdomen, pelvis and spine anteroposterior radiographs for 5–15 year olds, and less than 0.03 mSv for 0 and 1 year olds. Doses for examinations performed without a grid were only 20% of those for which a grid was used in the X-ray room studied. Significant reductions in doses for paediatric radiology can be achieved, where the use of grids can be avoided.