Acta radiologica: diagnosis最新文献

In order to evaluate the usefulness of computed tomography (CT) and 131I meta-iodobenzylguanidine (131I-MIBG) scintigraphy for the localization of pheochromocytoma, a prospective study was undertaken in 23 patients with possible pheochromocytoma. Seventeen tumors were identified in 13 patients. Two tumors were extra-adrenal. CT was superior for locating tumors in the adrenal glands while 131I-MIBG scintigraphy was more useful in the detection of extra-adrenal pheochromocytoma. Together with adrenal and extra-adrenal pheochromocytoma, the sensitivity for locating the tumor was calculated as 82 per cent (14/17) for CT and 76 per cent (13/17) for 131I-MIBG scintigraphy, respectively. One adrenal tumor (1 cm in size) only was missed by both methods. No false positive CT scans of 131I-MIBG scintigraphy were obtained in the remaining 10 patients who had possible pheochromocytoma but were excluded. These results indicated that CT and 131I-MIBG scintigraphy were both useful tools for detecting pheochromocytoma.

Stercoral obstruction in a young woman with disseminated phaeochromocytoma was diagnosed and treated successfully using an enema of isosmolar iohexol (Omnipaque) and 1% polysorbate 80 (Tween 80) without complication. Surgical intervention was thus avoided. A low osmolality water-soluble contrast medium (iohexol 150 mg I/ml) with a wetting agent (1% Tween 80) was used because a barium suspension would have inspissated, exacerbating the constipation and a hyperosmolar contrast medium might have precipitated a hypertensive crisis and destabilized her critical salt and water balance.

The elevation of the pharynx and larynx at swallowing in 10 patients with a defective relaxation of the cricopharyngeal muscle, was compared with that in 10 normals. The pharynx and larynx moved higher among patients with a defective relaxation of the cricopharyngeal muscle. Therefore, it can be concluded that a defective relaxation of the cricopharyngeal muscle at swallowing has no relationship to a defective pharyngo-laryngeal elevation.

Image features in the radiograph produced by deformation of a liquid surface by surface tension and by the density gradient in a diffusion layer may present unexpected difficulty of interpretation. Such features have been analysed in model experiments, which have been reported earlier. The aim of the present investigation was to examine the occurrence and the clinical implications of corresponding phenomena in routine radiographs. In the human body liquid surfaces and diffusion layers can occur only in cavities, both normal and abnormal. A liquid surface tends to extend up a cavity wall to form a meniscoid or, if the cavity is small enough, a discoid. The liquid surface continues further up the wall as a liquid film. The shape of the meniscoid and the discoid varies with the shape and inclination of the wall. Most of the image features of interest are produced by rays that are tangential to a horizontal surface, a meniscoid, a discoid or a concave wall, any of which is visualized as an internal boundary with a light Mach line. When the wall is convex towards the cavity the meniscoid is saddle-shaped and an external boundary with a dark Mach line is produced. The horizontal part of a liquid surface can be touched only if it is at the same level as the focus of the roentgen tube. A liquid surface at any other level can be touched in its meniscoid only by rays that are not horizontal. It is reproduced as an internal boundary, slightly concave upwards; above this boundary the rest of the liquid surface is reproduced as a wedge field.(ABSTRACT TRUNCATED AT 250 WORDS)

A non-ionic diagnostic medium, iohexol, was administered by subarachnoid injection to groups of six cynomolgus monkeys and compared with the vehicle, physiologically normal saline, and/or saline of equal osmolality to determine its potential for increasing total protein and leucocyte levels in cerebrospinal fluid. Also investigated was the effect of repeated spinal taps not subsequently followed by the intrathecal injection of test or control articles. In the monkey, unlike man, low-level leucocyte counts were consistently observed following initial withdrawal of spinal fluid. Elevated leucocyte and total protein levels were observed in the present investigations one day to a week after intrathecal injection of radiopaque, vehicle or saline solution. Total protein returned to normal levels earlier than did leucocyte counts. However, repeated needle puncture alone was found to be sufficient to cause an elevation of leucocytes 3 to 4 times the baseline level, while inflammatory effects were observed histologically only when autopsy was performed soon after the final spinal tap.

Transarterial injection of modified iodized oil was performed in 48 patients with hepatoma. In 41 cases an adriamycin and/or mitomycin C-iodized oil suspension was administered into the proper hepatic artery or peripheral hepatic branches. A reduction in tumor size of over 50 per cent was obtained in 14 of the 33 patients in whom CT examination was performed before and after treatment. Serum alpha-fetoprotein levels decreased in 20 of 21 cases within the first month after injection. The one-year survival rate was estimated at 55 per cent in advanced hepatoma. In 7 patients, transarterial internal irradiation using radioactive iodized oil was carried out. A decrease in tumor size was observed in all cases and in alpha-fetoprotein levels in 6 cases. One patient with severe liver cirrhosis died in hepatorenal failure. No severe complications or other adverse reactions were encountered with either of the methods.

The reliability of computed tomography (CT) using different criteria for abnormal size of retroperitoneal lymph nodes (5, 10, 15 mm in largest diameter) was evaluated prospectively in 90 consecutive patients with a non-seminomatous testicular tumor and lymph nodes less than 20 mm at CT. Correlation was made with histologic findings following retroperitoneal lymphadenectomy. Histologic examination revealed metastases in 38 patients (42%). Using a strict criterion of 15 mm for abnormal node size, sensitivity was 37%, specificity 98%, positive predictive value 93% and negative predictive value 68%. A relaxed criterion of 5 mm led to a sensitivity of 71%, specificity 67%, positive predictive value 61% and negative predictive value 76%. Overall accuracy was approximately 70% with the 5, 10 and 15 mm criteria for abnormal size. The inability of a normal scan to exclude metastases was the main limitation of CT.

In order to elucidate the pharyngo-esophageal segment in normal and abnormal conditions the width of the pharyngo-esophageal junction area on three different levels: hypopharynx, infracricoid segment of the cervical esophagus (ICCO) and cervical esophagus was measured in 150 non-dysphagial volunteers and in 252 dysphagial patients examined with cineradiography during barium swallowing. The result indicates that a narrow ICCO in absolute figures reflects the size of the swallowed bolus and is not a predictor of pharyngeal abnormality, per se. However, when the width of the ICCO in a.p. projection is less than 3/4 of the width in lateral projection this can indicate a narrow ICCO and should lead to endoscopy for further evaluation.

The gastrointestinal tract is being used to an increasing extent as a route for smuggling narcotics. Small, swallowed packages overwrapped with condoms or other materials are usually not detected by the customs authorities. Conventional abdominal radiography may indicate foreign bodies surrounded by a characteristic thin layer of gas and located in the gastrointestinal tract. Some short case histories, and the radiologic findings in four heroin 'body packers' are presented.