Australasian radiology最新文献

In clinically severe cervical spondylosis, imaging plays a vital role in surgical decisions. A prime factor is acquired canal stenosis with cord compression. To validate this concept, the clinical and imaging features of 20 patients with spondylotic myelopathy and 24 with radiculopathy were retrospectively reviewed. All had computed tomographic myelography (CTM) as part of their clinical work-up. The patients' clinical severity was graded as mild, moderate and severe; the age, length of illness and a history of eventual surgery or otherwise were recorded. At the level of maximum compression the following parameters were obtained from the axial CTM images: surface area and ratio of the anteroposterior to the transverse diameter of the cord; subarachnoid space and vertebral canal areas. Data were statistically analysed. A significant association exists between surgery and increasing severity of symptoms (P = 0.04), and advancing age (P = 0.01). These associations hold true for myelopathy and radiculopathy. A strong association is present between surgery and the surface area of the cord (P = 0.01), being applicable to myelopathy only. The other parameters show no association with surgical decisions. It is concluded that with myelopathy a narrow cord area at the level of maximum compression, and moderate--severe functional impairment are indicators for surgical intervention.

The typical CT appearance of a duodenal diverticulum is of a rounded air collection with or without fluid or contrast. An unusual case in which gas bubbles mixed with particulate matter mimicked faecal material in the large bowel is presented here. A similar appearance has been described in abnormally dilated small bowel, usually associated with obstruction, and is probably due to stasis of undigested food.

Long-term gastrostomy tubes have a well-accepted role in providing nutritional support. Traditionally they have been placed by surgeons and by endoscopists. In the last decade, radiologists have come to play a major role in the placement of gastrostomy and gastrojejunostomy devices, and can usually do so as effectively and at lesser expense. A technique for placement is outlined, with a discussion of patient selection and complications. A review of the literature is provided.

Nasopharyngeal carcinoma (NPC) shows a high frequency of skull base erosion and intracranial spread. This tumour is usually treated with radiation therapy. The medial and inferior portions of both temporal lobes are included within the radiation portals. These areas are therefore potential sites of radiation-induced necrosis. It is important to recognize this complication and separate it from intracranial tumour recurrence because the treatments of these entities are different.

The presence of a fatty liver often complicates the interpretation of abdominal computed tomography (CT). Abnormalities in or adjacent to the liver, including dilated bile ducts, liver masses and subphrenic collections, may be masked by the fatty liver. Furthermore, normal structures may simulate pathological conditions. Five cases are presented to illustrate some of these diagnostic pitfalls.

The Mammography Quality Assurance Programme, recently established by the Royal Australasian College of Radiologists, has processed the first 50 applications. This programme, which closely follows the programme of the American College of Radiology (ACR), utilizes phantom film images, thermoluminescent dosimetry measurement of mean glandular dose, processor control charts, clinical images, equipment reports and required survey information to establish that a centre conforms to a minimum standard in mammography. The present paper describes the initial results of the first phantom images, dose measurements, processor control and survey information. A film review panel of six members has been trained in phantom film reading. Their evaluation of phantom films was compared with film readings by members of the ACR and was found to be in close agreement. Fifty films have been evaluated up to the present time with a failure rate of 26%. The major causes of failure were unacceptable film artefacts and poor contrast (as indicated by reduced fibre and mass visibility). A surprising result was the high failure in processing, where 23% of units reviewed had significant problems, including failure to keep the processor within required control limits. Only one centre recorded a mean glandular dose above 2 mGy with no centre over the 3 mGy limit. A review of the frequency of the quality control testing shows that the acceptance of quality assurance in mammography, while greater than in the initial stages of the ACR programme, is less than current US practice. These initial results for the accreditation process probably reflect an initial period of adjustment, as seen by the high pass rate achieved by centres that have resubmitted material to gain accreditation.

Lymphangiomas are congenital malformations of the lymphatics that are curable by extirpation. Accurate delineation of lesion extension is important for pre-operative diagnosis, surgical planning, and assessing recurrence. The radiologic findings were retrospectively evaluated to determine the imaging appearance of these benign tumours. The plain radiographs, barium meal, ultrasound, CT, and MR images of 18 patients with one or more pathologically proved lymphangiomas were reviewed. Plain radiography and barium study showed masses displacing adjacent organs. Ultrasound examination showed uni- or multilocular cystic masses with smooth, thin or irregular, thick walls. Enhancement of the cyst wall was variable on CT and MR studies. The CT density of the fluid ranged from -4 to 34 HU depending on the lipid content and the presence of haemorrhage. The cysts were isointense to muscle on T1-weighted and hyperintense to fat on T2-weighted MR images. The MR imaging delineated the tumour lesion extension more clearly than ultrasound and CT scans. Ultrasound, CT, and MR imaging are valuable for evaluating lymphangiomas. Magnetic resonance imaging allows accurate determination of lesion extension.