Small-bowel lymphoma and regional enteritis: radiographic similarities.

Lymphoma and regional enteritis may demonstrate strikingly similar patterns in the small bowel. Fifty cases of regional enteritis and small-bowel lymphoma were reviewed. Of these, there were 12 cases of both diseases in which a confident radiographic distinction could not be made. Both diseases may narrow the terminal ileum, present as inflammatory processes, and demonstrate nodular patterns. Other similarities include aneurysmal dilatation, several types of ulceration, fistula formation, mesenteric masses, and involvement of the terminal ileum either alone or in association with skip areas. Clinical implications and the pathologic processes responsible for the radiographic similarity between these entities are discussed.

Computed tomography of the abnormal pericardium.

Computed tomographic (CT) findings in 18 patients with documented pericardial disease are reported. The pericardium appears as a thin, curvilinear, 1- to 2-mm-thick density best seen anterior to the right ventricular part of the heart. Pericardial abnormalities detected by CT include effusions, thickening, calcification, and cystic and solid masses. Computed tomography is complimentary to echocardiography in its ability to more accurately characterize pericardial effusions, masses, and pericardial thickening.

Computed tomography of the normal pericardium.

Computed tomographic (CT) scans of 100 patients were reviewed to establish the normal thickness of the pericardium. The pericardium was identified in 95 of 100 patients. The mean width of the thinnest portion of the pericardium was 2.0 +/- 0.6 mm (1 SD) in males (N = 46) and 2.3 +/- 0.5 mm (1 SD) in females (N = 49). The mean width of the combined series was 2.2 +/- 0.6 mm (N = 95). In none of the 95 hearts reviewed was the width of the thinnest portion of the pericardium greater than 4 mm. Focal changes in width of the pericardium were a normal finding in patients without documented pericardial disease.

Cytologic bile examination in the diagnosis of biliary duct neoplastic strictures.

Cytodiagnosis of the bile is not frequently thought of as a method of obtaining a histopathologic diagnosis of the cause of a neoplastic biliary duct stricture. However, cells surrounding the biliary ducts are continuously exfoliated into bile and become available for cytologic examination whenever bile is collected. Nineteen patients with obstructive jaundice are reported. In seven of 15 with neoplastic biliary duct strictures, cytodiagnostic examination showed tumor cells. There were no false-positive results. The sensitivity of bile cytodiagnosis in this series was 47%, its specificity was 100%, and its accuracy was 58%.

Secondary esophageal tumors.

Secondary esophageal carcinoma usually originates from a primary site in either the lung or breast and produces obstruction and symptoms that frequently mimic a benign esophageal stricture or primary esophageal carcinoma. Esophagoscopy shows a smooth identation, usually covered with normal mucosa; the appearance resembles a benign esophageal stricture. Esophageal biopsy in patients with secondary tumors is often negative for carcinoma. The radiologist plays a significant diagnostic role by his ability to show that the cause of the stricture is extramucosal and may be due to a secondary carcinoma involving the esophagus.

Gated cardiac computed tomography with a motion phantom.

CT images of the heart are significantly degraded by the effects of motion during the scanning interval. The use of electrocardiographic (ECG) gating to provide "stop-action" cardiac images remains limited by artifacts. A motion phantom has been constructed to allow systematic study of the artifact structure of ECG-gated images and to isolate the origins of these artifacts. "Stop-action" reconstructed images are presented demonstrating two classes of artifacts: (a) pinwheel artifacts that appear at the edges of high-contrast moving objects; and (b) linear streaks occurring in relation to missing views when an incomplete angular set of projections is used for image reconstruction with the convolution back-projection algorithm. These results underscore the use of the motion phantom for the analysis of image artifacts and stress the need for new CT reconstruction algorithms which are optmized for "stop-action" scanning.

Diameter of arterial microvessels trapping 8--10 micron, 15 micron and 25 micron microspheres as determined by vital microscopy of the hamster cheek pouch.

An assumption inherent in the use of microsphere methodology for measuring regional blood flow is that microspheres are removed from the circulation by impacting in arterial vessels of approximately their own diameter. We investigated the in vivo relationship between the diameter of varying size microspheres and the calibre of trapping microvessels within the hamster cheek pouch. Intracardiac injection of 8-10, 15 +/- 5, 25 +/- 5 micron carbonized microspheres with diversion of the cardiac output into the bracheocephalic trunk provided direct, in vivo visualization of the impaction sites of these various size microspheres within the cheek pouch microvasculature. Fifteen micron microspheres usually impacted at the orifice or neck of small arterioles and protruded into the lumen of the parent vessel. Eight to ten micron microspheres lodged in vessels with a mean diameter of 11.5 +/- SD 3.4 micron indicating that they usually impacted primarily in terminal arterioles.

Profile roentgenographic features of benign greater curvature ulcers.

Certain roentgenographic features have been considered typical of benign gastric ulcers, based almost entirely on studies of the lesser curvature. However, these features frequently are not present on the profile view in benign greater curvature ulcers. Moreover, features stated to suggest malignancy in gastric ulcers are commonly simulated by benign greater curvature ulcers. The authors reviewed the profile roentgenographic features of 19 benign greater curvature ulcers and found that they often appeared to be intraluminal and had shouldered edges due to spasm of the surrounding circular muscles. In 6 patients the adjacent gastric contour was scalloped. These features frequently cause radiologists to misinterpret benign greater curvature ulcers as malignant.

CT-pathologic correlations in Hodgkin's disease and non-Hodgkin's lymphoma.

In order to assess its potential uses in the staging and treatment planning of lymphoma, CT was performed in 27 newly diagnosed, previously untreated patients with Hodgkin's disease or non-Hodgkin's lymphoma; 18 staging laparotomies provided pathologic correlations. CT detected and defined disease in areas not well evaluated by conventional techniques (high para-aortic, mesenteric, splenic hilar nodes). CT interpretation of splenic size and weight correlated well with splenic weight confirmed at pathology. Nodules were identified in several spleens containing foci of lymphoma.

Upper esophageal responses to intraluminal distention in man.

This investigation determined the site(s) of elicitation and origin of secondary peristalsis in the human esophagus and characterized the upper esophageal sphincter (UES) and proximal esophageal body responses accompanying intraluminal distention. In 7 normal persons, an intraluminal transducer probe manometrically recorded the UES and 5- and 10-cm levels of the esophageal body. A second probe with a balloon attached 2 cm above the proximal strain gauge was located so that the balloon was 3 and 4 cm below the UES and 4 distentions were done. The balloon probe was moved in 2-cm increments (four distensions at each site) until lower esophageal sphincter pressures were recorded. No secondary peristalsis occurred after distention in the proximal 6 cm. The incidence of secondary peristalsis increased as the distention site moved distally. Sixty-nine per cent of secondary peristaltic waves orignated in the esophageal body proximal to the distention site. The UES pressure significantly increased over resting pressure (augmentation) during 63% of distentions. The esophagus proximal to the balloon and below the UES usually responded to distention with augmentation. Augmentation of the UES and proximal esophageal body in response to esophageal intraluminal distention and the resultant initiation of secondary peristalsis above the distention site comprise a highly integrated pressure barrier to esophagopharyngeal reflex.

Early experience with the Varian Six Second body scanner in the diagnosis of hepatobiliary tract disease.

Thirty-four patients with liver disease were studied with a research model of the Varian Six Second body scanner. Useful information was gained in patients with a variety of hepatic disorders. This scanner permits resolution of normal hepatic parenchymal detail which has not been reported previously and has reduced the streak artifacts originating from high- and low-CT objects which have been a major source of image degradation with other units.

Stop-action cardiac computed tomography.

Computed tomographic (CT) cardiac imaging in vivo has been hampered by motion of the heart during its cardiac cycle. A technique of post data-acquisition correlation of the angular projection data using the electrocardiogram as a reference signal is described. This method produced seven "stop action" images of the heart and resulted in delineating morphological detail not recognizable on the conventional CT scan.