Computed tomography of benign angiomatous lesions of the extremities.

Thirteen patients with benign angiomatous lesions of the extremities were evaluated by CT. The relationship of the lesion to specific muscle groups and fascial planes was defined better by CT than on plain radiography or angiography. Computed tomography without contrast enhancement demonstrated well circumscribed masses of lower attenuation value than the surrounding muscle.

CT assistance for fluoroscopically guided transthoracic needle aspiration biopsy.

Five cases are presented that illustrate the utility of obtaining limited CT prior to fluoroscopically guided biopsy in patients who have lung or mediastinal lesions that cannot be adequately localized by chest radiography. Each case describes a unique setting in which the CT images facilitate accurate and safe biopsy needle placement. The rare requirement for biopsy using CT alone, which can be considerably more time consuming, is emphasized.

Intraarterial digital subtraction angiography in hypertensive azotemic patients.

Ten intraarterial digital subtraction angiography studies in nine azotemic patients were reviewed to assess the technical adequacy and the effect of contrast load on renal function. All studies were of diagnostic quality. In only two of 10 studies was there a mild transient deterioration in the degree of renal insufficiency.

Ventilation-perfusion scanning and pulmonary angiography: correlation in clinical high-probability pulmonary embolism.

During a 3-year period, 173 clinically selected patients underwent pulmonary angiography to confirm or exclude acute pulmonary embolism. All patients had undergone ventilation-perfusion (V/Q) scanning (167 patients) or perfusion scanning alone (six) before angiography. Angiography was done because the results of the V/Q scanning did not satisfy the clinician's needs for certainty.

Computed tomography of the normal mesentery.

Thirty patients were studied to evaluate the CT appearance of the normal mesentery and its vasculature. Mesenteric vessels were identified by determining their relations to segments of the small bowel and colon in the 30 patients. Jejunal and ileal branches supplying small bowel were identified in all patients.

Modified Johnson basket for antegrade stone extraction.

A modification of a classic Johnson stone basket has been made, such that this basket can pass easily over an angiographic guide wire. With this modification, the Johnson stone basket is an excellent instrument for use in an antegrade or a retrograde fashion for retrieving impacted ureteral calculi. Eleven patients had ureteral calculi manipulated.

CT demonstration of hyperdense renal carcinoma.

Sharply demarcated homogeneously hyperdense renal lesions have been found to be benign renal cysts, with hemorrhage or a high protein content the most common etiology of the high density. A similar hyperdense renal lesion is presented that was found to be a renal adenocarcinoma. This lesion showed mild contrast enhancement on CT and was found by ultrasound to be a solid mass.

Somatostatinoma of the endocrine pancreas: CT findings.

Somatostatinoma is the rarest of the pancreatic islet cell tumors with only eight previously reported cases. We report a recent case in a 62-year-old man including CT findings and 1 year follow-up.

CT diagnosis of ruptured abdominal aortic aneurysm.

Abdominal computed tomography was performed in six patients with suspected ruptured abdominal aortic aneurysm but in whom an alternate clinical diagnosis was seriously considered. In each patient, a large aortic aneurysm was demonstrated in association with a retroperitoneal accumulation of high-density blood. The retroperitoneal blood was primarily confined to the extracapsular perinephric space.

Mesenteric vein thrombosis: CT identification.

Superior mesenteric vein thrombosis was identified on computed tomographic scans in six patients. In each case, contrast-enhanced scans showed a high-density superior mesenteric vein wall surrounding a central filing defect. Four of the six patients had isolated superior mesenteric vein thrombosis.

Diagnosis and significance of liver metastases in small cell carcinoma of the lung.

One hundred fifty-seven consecutive patients with small cell lung cancer seen at the National Cancer Institute over a four-year period underwent a series of pretherapy liver staging procedures to determine optimal means of detection and prognostic implications of hepatic metastases. Liver evaluation included physical examination, liver function tests, and liver scan (radionuclide or computerized tomography [CT]), as well as percutaneous and/or peritoneoscopy-directed liver biopsy when possible (74%). Liver metastases were detected in 26% of patients.

Computed tomography of high density renal cysts.

Eleven patients are described whose computed tomography (CT) examinations showed homogeneous, high density (62-76 Hounsfield units) renal masses. In two patients a hemorrhagic benign cyst was found at surgery. In the remaining nine patients the constellation of CT and clinical findings supported the benign nature of this lesion.

Computed tomography of the kidney.

Computed tomography has had a dramatic impact on the practice of uroradiology. The transverse image plane and excellent density differentiation allow more accurate diagnoses and often preclude the necessity for more invasive diagnostic tests or surgery. Refinements in equipment and diagnostic techniques promise further improvements in diagnosis and disease monitoring.

Effect of region assignment on relative renal blood flow estimates using radionuclides.

To determine the value of the initial phase of the Tc-99m DTPA renogram in the direct estimation of relative renal blood flow in dogs, the ratios of the slopes of renal time-activity curves were compared with the ratios of measured blood flow. Radionuclide results were dependent on region-of-interest (ROI) and background ROI assignment, and correlated well with measured relative flow only with a maximum renal outline region. Curve slope ratios correlated well with measured flow ratios with and without background correction, while 1- to 2-minute uptake ratios correlated well only when corrected for background.

CT differentiation of thoracic aortic aneurysms from pulmonary masses adjacent to the mediastinum.

Paramediastinal masses adjacent to the aorta require a diagnostic evaluation to differentiate between tumor and aneurysm. It has been suggested that neoplasm may enhance sufficiently to be confused with a vascular structure or that a clot filled aneurysm may simulate a neoplasm by not filling with contrast medium. Five patients, two with thoracic aneurysms, two with malignancy, and one with a malignancy and an aortic dissection, are presented in whom bolus injection computed tomography (CT) was able to distinguish between aneurysm and mass.

Computed tomography of renal oncocytoma.

Six patients with small solid renal tumors were evaluated by computed tomography (CT). Two patients had renal oncocytomas, three had small renal cell adenocarcinomas, and one had separate foci of each of these tumors in the same kidney. We describe several features that may alert the clinician to the possible presence of oncocytoma.

Percutaneous dissolution of renal calculi using ultrasonic litholapaxy.

The surgical treatment of renal calculi has been markedly changed by percutaneous manipulation and ultrasonic dissolution. The low morbidity and decreased cost of this procedure make it an obvious choice over classic surgical operations. We report our experience with percutaneous ultrasonic stone dissolution in 23 patients.

Iopamidol: new, nonionic contrast agent for excretory urography.

Iopamidol, a new, nonionic contrast agent, was evaluated in 18 patients undergoing excretory urography. None of the 18 patients experienced any side effects or adverse reactions. No abnormalities were noted in serum chemistries, complete blood cell counts, urinalyses, or electrocardiograms.

Percutaneous transluminal angioplasty in diabetic patients: an effective treatment modality.

Percutaneous transluminal angioplasty (PTA) was performed for nonhealing ulcers, severe claudication, or rest pain in 10 patients with diabetes mellitus. Twenty-two atherosclerotic lesions were dilated in 15 extremities, including 16 iliofemoral arteries and 6 superficial femoral arteries. The procedure was technically successful in all patients and 8 of 9 (89%) with clinical follow-up showed improvement clinically after the procedure.

Closed-system venography in the evaluation of angiodysplastic lesions of the extremities.

Closed-system venography is a minimally invasive, well tolerated method for diagnosing and delineating extremity angiodysplastic lesions. This method involves passive filling of the vascular tree after compressive exsanguination of an extremity and extrinsic occlusion of its arterial supply and venous drainage, thereby creating a static, closed system. Closed-system venography was done in 17 patients, where it correctly identified 11 of 12 surgically confirmed vascular abnormalities.

The radionuclide renogram as a predictor of relative renal blood flow.

Radionuclide renograms obtained with Tc-99m-DTPA were used to calculate relative renal blood flow in 16 dogs. In 13 of these dogs, relative blood flow ratios (R:L) calculated from the renograms were correlated with ratios measured with an electromagnetic flowmeter or with radiolabeled microspheres. The results indicate that Tc-99m-DTPA renograms can be used to make an accurate prediction of relative renal blood flow.

Primary lower extremity lymphedema: CT diagnosis.

The CT findings of two cases of primary lymphedema of the lower extremities are presented. CT showed a coarse, nonenhancing, reticular pattern in an enlarged subcutaneous compartment. CT excluded the diagnosis of secondary lymphedema from an obstructing mass by demonstrating a normal retroperitoneum and pelvis.