Twenty-five patients who had lymphoceles underwent sectional imaging and interventional radiologic procedures. Viewed using sonography, lymphoceles were hypoechoic to anechoic, occasionally with internal septa and debris. Low numbers (occasionally negative values) were observed using computed tomography (CT); these numbers strongly suggest the diagnosis of lymphocele. Calcification was observed on CT images of one patient. Diagnostic aspiration revealed tan to yellow fluid containing many lymphocytes; pathognomonic fat globules were observed in four cases. Malignant cells were found in two collections, an unusual occurrence. Therapeutic needle aspiration and short-term catheter drainage were usually unsuccessful (only one of five patients [20%] was cured). Long-term (1-5-week) catheter drainage cured 11 of 14 patients (78.6%). Sclerosing agents may have been beneficial for lymphocele obliteration in three of four patients. For most patients, lymphoceles may be diagnosed and treated successfully using radiologic means.

To determine the role of ultrasound (US) in patients with acute flank pain and suspected acute urinary tract obstruction, a prospective study was performed on 20 patients comparing US with emergency excretory urography. US was not as sensitive as excretory urography for diagnosing hydronephrosis, for detecting ureteral or renal calcification, or for diagnosing forniceal rupture. Although US is an effective screening modality for hydronephrosis in patients with chronic renal obstruction, it is not useful for evaluating patients with acute flank pain in whom acute obstruction may be present. In this group of patients, excretory urography remains the examination of choice.

The sensitivity of duplex ultrasonography (US) for detecting deep venous thrombosis of the lower extremity was compared with that of venography in a prospective study of 54 patients. Doppler analysis of the common femoral vein and US imaging of the deep venous system from the common femoral vein to the popliteal vein was performed. Common femoral vein response to the Valsalva maneuver was recorded. Sonographically visible thrombi and abnormal vein compressibility were 91% sensitive for the common femoral vein, and 94% sensitive for the superficial femoral or popliteal veins, with no false-positive examinations. Abnormal Doppler flow and abnormal response of the common femoral vein to the Valsalva maneuver enabled thrombi to be detected only in the common femoral and iliac veins. Combined data allowed accurate diagnoses in all patients with deep venous thrombosis proximal to the deep calf veins. US should be the screening examination of choice for evaluating patients with suspected lower extremity deep venous thrombosis.

No abstract

Whether placental migration occurs is debatable. To determine the incidence of placenta previa in early pregnancy and the frequency of placental migration, a retrospective analysis was undertaken of 2,087 consecutive obstetrical sonograms obtained during a 23-month period. Among 849 patients scanned between 14 and 26 weeks after conception, placenta previa was diagnosed using ultrasonography (US) in 53 patients (6.2%). This diagnosis was confirmed at surgery in 15 patients (1.8%); there were 12 cases of central previa and three cases of partial previa. Retrospective analysis revealed that in 25 cases, technical factors, such as an overly distended urinary bladder (19 cases) or focal uterine contractions (six cases), were responsible for the false-positive diagnoses. In the 13 remaining patients, however, there were no obvious technical difficulties to account for the diagnosis of previa. Migration did not occur in any of the patients with central previa. It appears that placental migration may occur, although less frequently than has previously been reported. Furthermore, this study suggests that migration does not occur in patients with central previa.