Long-term follow-up after TIPS: use of Doppler velocity criteria for detecting elevation of the portosystemic gradient.

Purpose: To evaluate the performance of Doppler ultrasound as a screening test for detecting elevated portosystemic gradients in failing transjugular intrahepatic portosystemic shunts (TIPS).

Materials And Methods: Twenty-seven of 61 patients who underwent TIPS creation between November 1991 and March 1996 were studied. At routine intervals, angle-corrected velocity measurements of portal venous and intrashunt blood flow (at the portal venous, middle, and hepatic venous levels of the shunt) were obtained.

Contemporary diagnostic approaches for nonpalpable carcinoma of the breast: the role of the radiologist.

Over the past 25 years the radiologist's role in the diagnosis of breast cancer has expanded from merely confirming the clinical suspicion of neoplasm to detecting occult nonpalpable tumors and now percutaneously obtaining tissue for histologic assessment. The cancer the radiologists discover is smaller in size and earlier in stage, allowing more conservative surgical approaches. This, coupled with adjuvant radiation therapy and chemotherapy, is producing newly demonstrated mortality reduction in this disease so feared by American women.

Color Doppler sonography: anatomic and physiologic assessment of the thyroid.

The purpose of this study was to assess the potential application of color Doppler sonography in thyroid imaging. Thyroid nodules and other thyroid pathology detected by color Doppler ultrasound and nuclear scintigraphy were compared in 115 patients. The majority of "cold" nodules demonstrated a peripheral rim of color flow and no internal color flow with color Doppler sonography.

Benign circumscribed breast masses. Mammographic and sonographic appearance.

Mammography is an excellent screening tool for the detection of breast masses. One of the goals of the radiologist is to separate benign breast masses warranting no intervention from the indeterminate and malignant masses that require histologic evaluation. Thorough mammographic and sonographic work-up of lesions detected at screening will reduce the number of biopsies performed and increase the true positive biopsy rate.

Is bilateral lower extremity compression sonography useful and cost-effective in the evaluation of suspected pulmonary embolism?

Objective: Because deep venous thrombosis is clinically linked with pulmonary embolism and often treated similarly, we sought to assess the usefulness of obtaining bilateral lower extremity compression sonograms when findings on ventilation-perfusion lung scans indicate a low or indeterminate probability of pulmonary embolism. Demonstration of deep venous thrombosis would provide a rationale for treating both pulmonary embolism and deep venous thrombosis.

Materials And Methods: Two hundred twenty-three consecutive patients with suspected pulmonary embolism had ventilation-perfusion lung scans and concurrent bilateral lower extremity compression sonograms; 34 also had pulmonary arteriography.

Computerized tomography in persons with Down syndrome and atlantoaxial instability.

Atlantoaxial instability has been reported to occur in 9-31% of persons with Down syndrome. The authors studied a subsample of patients with this chromosomal disorder who had both routine roentgenograms and computerized tomographic examinations. Computerized tomography revealed numerous skeletal anomalies of the C1-C2 region as well as spinal cord compression that were not visualized on plain roentgenograms.

A longitudinal study of atlanto-dens relationships in asymptomatic individuals with Down syndrome.

This study was designed to investigate the natural history of atlantoaxial instability in individuals with Down syndrome and to determine whether significant changes in C1-C2 relationship are taking place over time. Although more than 400 patients with Down syndrome who are presently followed at the Child Development Center had cervical spine radiographic examinations in the past, only 141 patients who had serial radiological examinations and whose radiographs were available for reevaluation participated in this study. The results of our investigations revealed that there were only minor changes (1 to 1.

Diazald, a newly recognized antimicrobial agent and its spectrophotometric determination.

Diazald, a chemical intermediate for the synthesis of biologically active compounds, was found to be a potent in vitro antimicrobial agent against yeasts, yeast-like and filamentous fungi as well as Gram-positive and Gram-negative bacterial strains. Its activity is not inhibited by either para-aminobenzoic acid (PABA) or the nitroso group-specific 2-aminothiazole-methoxyimino acetic acid (ATMAA). This suggests that the molecule as such is responsible for the antimicrobial activity.

Skeletal anomalies of the upper cervical spine in children with Down syndrome.

This study showed that a significantly greater number of children with Down syndrome (45 to 78) have cervical spine anomalies than an age- and sex-matched group of normal children (3 of 38). Moreover, children with Down syndrome who had atlantoaxial instability had an increased frequency of cervical spine anomalies (31 of 39) as compared with an age- and sex-matched group of children with this chromosome disorder who did not have atlantoaxial instability (14 of 39).

Radiation exposure to patients receiving routine scoliosis radiography measured at depth in an anthropomorphic phantom.

Concern about the amount of radiation received during scoliosis evaluation and treatment led us to measure radiation exposure in an anthropomorphic phantom to determine the increased risk of breast cancer in young women with scoliosis. Assuming that 22 radiographic examinations were performed over the course of scoliosis treatment, the increased relative risk of breast cancer was determined to be 0.22% in these patients.

Iatrogenic changes at the venotomy site after percutaneous placement of the Greenfield filter.

To determine the prevalence of iatrogenic abnormalities associated with percutaneous delivery of Greenfield filters, the authors prospectively evaluated 69 peripheral veins used for filter placement in 68 patients. Of the 69 venotomy sites, 63 were not associated with preexisting thrombosis and were evaluated with compression and Doppler ultrasound within 1 week of placement and over 13-541 days. New thrombosis developed at the puncture site in nine of 63 sites (14.

Grade I hydronephrosis: pulsed Doppler US evaluation.

This study was undertaken to determine whether the presence of blood vessels could mimic the appearance of grade I hydronephrosis on sonograms and thus cause false-positive readings. One hundred consecutive patients with grade I hydronephrosis were examined. Sample volumes were obtained with pulsed Doppler ultrasonography (US) at the site of the greatest separation of the central renal sinus echoes to determine if the separation was fluid accumulating in the collecting system, as in obstruction, or if the separation was actually caused by vessels that mimic hydronephrosis.

Ultrasound evaluation of cholelithiasis in the morbidly obese.

The ability to detect gallstones in the morbidly obese population has been questioned in recent literature. Utilizing state-of-the-art, real-time ultrasound equipment, 44 morbidly obese patients were examined prior to gastric exclusion surgery and concomitant cholecystectomy. The 91% sensitivity and 100% specificity of gallstone detection in this series matches the results for the general population.

Atlantoaxial instability in individuals with Down syndrome: epidemiologic, radiographic, and clinical studies.

Atlantoaxial instability is a relatively frequent finding in individuals with Down syndrome. We examined 404 patients with this chromosome disorder and observed their atlanto-dens intervals and spinal canal widths to be significantly different from children without Down syndrome. Significant differences were also noted between boys and girls with Down syndrome in spinal canal widths but not in atlanto-dens interval measurements.

Atlantoaxial instability in Down syndrome: roentgenographic, neurologic, and somatosensory evoked potential studies.

To identify patients with Down syndrome and asymptomatic atlantoaxial instability who are at increased risk for developing neurologic symptoms, we studied 27 patients with this skeletal disorder and compared them with an age- and sex-matched group of 27 patients with Down syndrome without atlantoaxial instability. A third group of six patients had symptomatic atlantoaxial instability. The mean atlanto-dens intervals and the mean spinal canal widths among the three groups were significantly different.

Deep venous thrombosis: US assessment using vein compression.

To assess vein compressibility as a simple ultrasound (US) technique to determine the presence of venous thrombi, 51 patients undergoing contrast material venography of the lower extremity because of a clinical suspicion of deep venous thrombosis (DVT) also underwent high-resolution US evaluation of the veins. DVT was diagnosed on 28 venograms. In 25 patients US studies demonstrated non-compressibility of the veins, indicating the presence of clot.

Renal obstruction in patients with ileal loops: US evaluation.

Ultrasound (US) is often employed as a screening test for hydronephrosis in the nondiverted kidney and has been used recently to evaluate the diverted kidney, specifically ileal loops, for obstruction. The utility of US in evaluating obstruction in patients with ileal loops has apparently not been previously explored. During a 2-year period, 87 kidneys drained by an ileal loop diversion were examined with US because of clinical indications of possible renal obstruction.

Symptomatic atlantoaxial subluxation in persons with Down syndrome.

In a prospective study 40 of 236 individuals with Down syndrome were found to have atlantoaxial instability. Whereas most of the 40 affected children were asymptomatic, seven patients exhibited various neuropathology. Historical data, neurologic findings, radiologic interpretations, and surgical management of these seven patients are described in detail.

Atlanto-axial instability in children with Down syndrome.

One hundred fifty-eight patients with Down syndrome underwent roentgenologic examinations of the cervical spine in neutral position, in hyperflexion, and in hyperextension. Fifteen children with Down syndrome were found to have a distance between the joint surfaces of 5 mm and more. The majority of these children were asymptomatic, one child displayed hyperactive deep tendon reflexes and two children were symptomatic and underwent surgery.