The "aortic nipple" as a sign of impending superior vena caval syndrome.

The development of dilatation of the left superior intercostal vein ("aortic nipple") on chest radiographic studies can be used as a clue to impending superior vena caval syndrome. Two cases are described in which detection of an "aortic nipple" on chest roentgenograms predated the clinical syndrome by seven to ten weeks. Since superior vena caval syndrome is a medical emergency, recognition of signs such as this which may significantly predate the "full-blown" syndrome have far-reaching implications in the care of patients.

Hydrostatic pulmonary edema in sheep. Effects of bronchial artery embolization on the plain chest radiograph.

RATIONALE AND OBJECTIVES: The bronchial circulation may influence pulmonary edema. This study evaluates possible effects of bronchoesophageal artery embolization on the plain film manifestations of hydrostatic pulmonary edema in sheep. METHODS: Anteroposterior and lateral chest radiographs were obtained during the induction of pulmonary edema both before and after embolization of the bronchoesophageal artery in six adult sheep. Interstitial lines and perivascular, segmental bronchial, proximal bronchial, carinal, tracheal, and parenchymal edema were evaluated. RESULTS: Only parenchymal edema was graded consistently. Though edema increased with left atrial pressure before embolization (P < .001), there was no similar change afterward. The embolized animals tended to be more edematous by the first film. CONCLUSION: Rather than any protective effect, bronchoesophageal artery embolization may increase edema. This model may be inappropriate for further investigation of the bronchial circulation in the development of human pulmonary edema.

Diagnosis and treatment of fluid-filled renal structures in children with ultrasonography and percutaneous puncture.

The application of ultrasonographic and percutaneous needle puncture techniques in the diagnosis of various fluid-filled renal anomalies has permitted rapid delineation of anatomic detail, more definitive physiologic evaluation, and drainage, when necessary, in a safe and cost-effective manner. Its usefulness in children is emphasized in 6 illustrated cases of male infants with minimally or nonopacified renal anomalies, one of the more difficult diagnostic problems in pediatric urology.

Permanent percutaneous antegrade ureteral stent placement without transurethral assistance.

A simple, one-step, permanent, percutaneous, antegrade insertion of a ureteral stent is described, utilizing a double, pigtail catheter. No transurethral assistance is necessary. The advantages of this simplified technique are presented, and the necessary prerequisites for its application are discussed.

Case report. Mycotic aneurysm of the superior mesenteric artery: report of a successful repair.

A case of a patient with a mycotic superior mesenteric artery aneurysm that was successfully repaired by the technique of restorative endoaneurysmorrhaphy is presented. Principles of diagnosis and management are delineated.

Practical aspects of gated magnetic resonance imaging of the pulmonary artery.

A practical clinical evaluation of the role of gated magnetic resonance imaging (GMRI) for the evaluation of congenital and acquired diseases of the pulmonary artery is presented, comparing GMRI to the already established usefulness of other various noninvasive and invasive imaging modalities.

Sonography of transjugular intrahepatic portosystemic shunts.

Transjugular intrahepatic portosystemic shunting (TIPS) is an effective procedure for relieving portal hypertension. Sonography can usefully assist portal vein puncture. Color and duplex sonography after TIPS demonstrates changes in hepatic vascular hemodynamics, detects complications, and confirms shunt patency. A large proportion of shunts will develop progressive stenosis over 12 months. Stenosis occurs because of pseudointimal hyperplasia in the stent or in the hepatic vein. Patent shunts are characterized by velocities in excess of 70 cm/s and hepatofugal flow in the portal circulation distal to the shunt. Although the cause of the stenosis can rarely be seen, velocities of less than 50 cm/s indicate shunt stenosis. Loss of cardiac pulsatility is another useful sign of shunt stenosis. Regular sonographic monitoring reliably detects stenosis, allowing stent revision and preventing recurrence of bleeding.

"Bell-shaped ureter," a radiographic sign of antegrade intussusception.

A unique case of a hitherto unreported antegrade intussusception of the ureter secondary to a lead pedunculated polypoid transitional cell tumor is presented. Radiological documentation and surgical verification are illustrated. An attempted explanation of the peculiar radiographic appearance proximal to and within the intussusception is given. The potential aid in preoperative recognition of such an entity is proposed.

Angiomyolipomas in tuberous sclerosis: subselective embolotherapy with alcohol, with long-term follow-up study.

The use of subselective renal artery embolotherapy with absolute alcohol, using balloon occlusion to prevent backflow, is described in treating three hemorrhaging angiomyolipomas in two patients with tuberous sclerosis. Embolotherapy was chosen to treat the extensive hemorrhage and to spare the normal renal parenchyma. Literature reports of this treatment are reviewed, indicating it is one of the best methods for achieving a safe, permanent, and complete ablation.

Therapeutic embolization of the renal artery with Gianturco coils: limitations and technical pitfalls.

The Gianturco coil, with or without Gelfoam, is particularly popular and effective in occluding renal arteries to control bleeding, devascularize tumors, close arteriovenous fistulas, and infarct kidneys in end-stage renal disease. However, without special precautions, successful embolization can suddenly be transformed into catastrophe. Representative reports of complications from medical centers across North America are used to illustrate the initial technical pitfalls of coil placement, as well as the more delayed complications that produce deviations from the usual postinfarction syndrome.

Obstruction of the inferior vena cava: a multiple-modality demonstration of causes, manifestations, and collateral pathways.

This article explores the causes and manifestations of obstruction of the inferior vena cava (IVC) with a multiple-modality approach. Caval obstruction may be due to thrombus, extension of a tumor, extrinsic compression, or intrinsic caval disease. Evaluation of the IVC should be tailored to the individual circumstance; no single modality is best in all situations. Although magnetic resonance offers multiplanar imaging, vena cavography or ultrasound are often necessary to exclude intraluminal tumor extension. Computed tomography is sensitive for intracaval thrombus and compression but does not delineate the hepatic IVC well. Nuclear venography demonstrates well the resultant collateral pathways, which can be separated into the deep, intermediate, superficial, and portal systems. Despite the clear visualization of these pathways with this modality, congenital caval anomalies, such as caval interruption with azygos continuation, can be confused with acquired caval disease.

Positron emission tomography with F-18-fluorodeoxyglucose to evaluate the results of hepatic chemoembolization.

BACKGROUND: Positron emission tomography (PET) using F-18-flurodeoxyglucose (18FDG) is an imaging modality allowing direct evaluation of cellular glucose metabolism. The purpose of this study was to examine the role of 18FDG-PET in monitoring chemoembolization therapy of patients with liver metastases from adenocarcinoma. METHODS: Thirty-four hepatic lesions in 4 patients were evaluated with 18FDG-PET before and 2-3 months after interventional therapy. All patients underwent transcatheter arterial chemoembolization. A total of nine PET studies were performed. Semiquantitative measurement of the metabolic activity of the lesions was performed using the standard uptake value (SUV) of 18FDG. Comparison was performed between sequential PET scans using Student's t test for paired data analysis. The PET findings were also compared with tumor marker levels measured at the time of the PET scans. RESULTS: Twenty-five of 34 lesions had decreased 18FDG uptake (SUV = 8 +/- 2 vs. 3 +/- 1; P < 0.00001), as expected in successful tumor chemoembolization. These findings were associated with a significant decrease in serum tumor marker levels (86 +/- 4%; P < 0.05) after treatment. However, there were 3 new lesions, and 6 of the 34 lesions demonstrated persistent or increased 18FDG uptake after treatment (SUV = 8 +/- 2 vs. 13 +/- 3; P < 0.05), consistent with the presence of residual viable tumor. These findings led to further interventional therapy in all patients. CONCLUSIONS: 18FDG-PET allows monitoring of response to treatment with hepatic chemoembolization in patients with liver metastases from adenocarcinoma. PET is a useful diagnostic tool and has the potential to be used to guide further interventional therapy.

Transjugular intrahepatic portosystemic shunt: US assessment with maximum flow velocity.

PURPOSE: To evaluate the ability of Doppler ultrasonography (US) to depict the patency of a transjugular intrahepatic portosystemic shunt (TIPS). MATERIALS AND METHODS: Twenty-eight patients were followed up after creation of TIPS with US, angiography, and endoscopy performed at regular intervals. Magnetic resonance (MR) angiography was performed in four patients. US was performed first, and the results were correlated with those at angiography. Measurements of maximum flow velocity (Vmax) were taken from the proximal part of the shunt. RESULTS: In normal shunts, mean Vmax was 95 cm/sec. Shunt obstruction was seen in 12 cases: occlusion in four and stenosis in eight. All cases of occlusion were detected with US and appeared as absent flow within the shunt. There was one false-positive diagnosis of occlusion. All cases of stenosis resulted in reduced Vmax (mean, 32 cm/sec; P < .001). After successful revision in seven patients, Vmax rose to a mean of 122 cm/sec. Artifact from the metal stent prevented flow assessment with MR imaging. CONCLUSION: US can be performed to evaluate shunt status, and Vmax is an accurate noninvasive parameter for assessing shunt patency.

The use of inferior vena cava filters in pediatric patients for pulmonary embolus prophylaxis.

PURPOSE: To report our experience with inferior vena cava (IVC) filters in pediatric patients. METHODS: Over a 19-month period, eight low-profile percutaneously introducible IVC filters were placed in four male and four female patients aged 6-16 years (mean 11 years). Indications were contraindication to heparin in six patients, anticoagulation failure in one, and idiopathic infrarenal IVC thrombosis in one. Six of the eight devices placed were titanium Greenfield filters. One LGM and one Bird's Nest filter were also placed. Two of the filters were introduced via the right internal jugular vein by cutdown, and the remainder were placed percutaneously via the right internal jugular vein or the right common femoral vein. Patients received follow-up abdominal radiographs from 2 to 13 months after IVC filter placement. RESULTS: All filters were inserted successfully without complication. Three of the patients died during the follow-up period: two due to underlying brain tumors at 2 and 12 months and a third at 6 weeks due to progressive idiopathic renal vein and IVC thrombosis. The remaining five patients were all alive and well at follow-up without evidence of IVC thrombosis, pulmonary emboli, or filter migration. CONCLUSION: IVC filter placement using available devices for percutaneous delivery is technically feasible, safe, and effective in children.

Three-dimensional color Doppler sonography before and after fibroid embolization.

Three-dimensional color Doppler sonography was performed within 1 hour, 1 day, 3 months, and 6 months of fibroid embolization in 20 patients who had a total of 31 fibroids greater than 2 cm in average dimension. The greatest decrease in vascularity occurred 1 day after the procedure, whereas the greatest volume change was found at the 3 month follow-up examination. In about one half of the patients scanned, depiction of fibroid vascularity by color Doppler sonography was found to improve the delineation of the size, location, and extent of myometrial involvement. Hypervascular fibroids (12 of 31) tended to decrease in size after treatment more than isovascular (10 of 31) or hypovascular ones (9 of 31). Additional investigations that are similar to this one will be needed to determine if three-dimensional color Doppler sonography can be used to predict those who will be responders, partial responders, or nonresponders to embolotherapy.

Percutaneous nephrostomy in neonates, infants, and children.

In a 20-month period, 13 percutaneous nephrostomies were placed in 10 pediatric patients ranging in age from one day to six and one-half years. The procedure was successful in all cases with no significant complications. Final diagnoses included ureteropelvic junction obstruction, ureterovesical junction obstruction, posterior urethral valves, and pyonephrosis. Localization of the obstruction as detected on initial antegrade nephrostography was found to be incomplete or incorrect in three patients. In one patient, both ureteropelvic and ureterovesical junction obstruction were present. In the other two patients, the misdiagnosis probably related to the difficulty of filling a distended, obstructed ureter prior to drainage.