Intracortical osteosarcoma; two-year delay in diagnosis.

Intracortical osteosarcoma is the rarest type of osteosarcoma. In most instances the tumor arises in the cortex of the femur, less commonly, in the tibia. We describe an 11-year-old patient with intracortical osteosarcoma of the tibia in whom the tumor was present for 2 years and became painful 3 months prior to presentation.

Wallstent migration following deployment in right and left bile ducts.

The Wallstent biliary endoprosthesis has recently been approved for treatment of malignant bile duct obstruction. Although minor changes in position have occurred, migration of these stents has been uncommon. The authors report a case in which migration occurred when stents were simultaneously deployed in the right and left bile ducts. Several mechanisms for this complication are postulated.

Dilated periportal lymphatics mimicking an anastomotic bile leak after liver transplantation.

Transhepatic cholangiography is commonly performed during postoperative evaluation of liver transplant patients. The authors describe a potential pitfall in the interpretation of these studies and illustrate that dilated interrupted lymphatics of the donor liver can mimic a periductal leak of contrast material.

Angiomyolipoma: postembolization liquefaction and percutaneous drainage.

A case of renal angiomyolipoma is reported, in which embolotherapy was followed by liquefaction of virtually the entire tumor. The liquified lesion was drained percutaneously.

Laser catheter thermal angioplasty: technique and early results in 34 patients.

The laser catheter is a nylon vascular catheter with a metal tip that has an end hole as well as side holes. The metal tip is heated by laser energy delivered through an optical fiber embedded in the catheter wall. The catheter may be advanced over a guidewire for use as an adjunct to balloon angioplasty or for use in smaller vessels as the exclusive method of recanalization. We used the catheter to treat 34 patients with 54 discrete vascular lesions in 35 extremities. Twenty patients were treated for clinically significant claudication and 14 for ischemic changes. Laser catheter-assisted balloon angioplasty was used to treat six iliac artery occlusions, two iliac artery stenoses, 10 superficial femoral artery occlusions, 12 superficial femoral stenoses, four popliteal artery occlusions, and three popliteal stenoses. Initial technical and clinical success in these patients, with follow-up periods of 3-6 months, was equivalent to the results of previous reports of laser probe-assisted balloon angioplasty. In 11 patients, 15 of 17 popliteal or tibial-peroneal lesions were treated with the laser catheter without subsequent balloon angioplasty. The treatment was successful in eight of these patients, with follow-ups for up to 6 months. Our results suggest that the laser catheter is a useful device for the treatment of vascular stenosis or occlusion when used either as an adjunct to balloon angioplasty or in smaller vessels as the exclusive method for angioplasty.

Inadvertent pancreatic embolization as a complication of hepatic carcinoid treatment--computed tomography appearance.

A patient with hepatic metastases from a carcinoid tumor was treated by hepatic artery embolization and developed pancreatitis. A subsequent computed tomography scan (CT) demonstrated evidence of pancreatic embolization. The CT findings are reviewed as well as the probable mechanism of the development of pancreatitis.

Infrapopliteal and below-knee popliteal lesions: treatment with sole laser thermal angioplasty. Work in progress.

Laser-assisted balloon angioplasty has been successfully performed in peripheral and coronary arteries; however, the ability to perform laser angioplasty alone without the need for subsequent balloon angioplasty has not been reported. In the present series, infrapopliteal and below-knee popliteal sole laser thermal angioplasty was successfully performed on 14 of 16 (88%) lesions in 10 patients. Initial clinical and hemodynamic improvement was observed in seven of 10 (70%) patients, with clinical failure noted in three nonsurgical candidates with poor distal vessel runoff. Short-term clinical follow-up (mean, 6 months) revealed 100% patency at the site of laser thermal angioplasty. Clinical success was maintained in five of seven (71%) patients; symptoms recurred in two patients who had undergone laser thermal angioplasty and adjuvant balloon angioplasty of superficial femoral artery lesions. Treatment of distal peripheral arterial lesions with laser thermal angioplasty alone is feasible; studies comparing it with conventional balloon angioplasty should be considered.

Experience with a new ureteral stent made of a biocompatible copolymer.

A double-pigtail ureteral stent made from a biocompatible copolymer was designed for antegrade insertion with a new coaxial system. Thirty-eight of these stents were successfully placed in 33 patients. Of eight stents used for benign temporary indications, two (two patients) occluded prematurely. One of these patients had retained stone fragments, which caused the 10-F stent to occlude 4 months after balloon dilation of a midureteral stricture. The second patient had a ureteroconduit stricture that was dilated and stented, but mucus occluded the 10-F stent 5 days after insertion. In 25 of the patients, 30 stents were placed for ureteral obstruction due to malignant neoplasms. Three patients died with patent stents, while surviving patients with malignancies continue to have functioning stents, for an overall mean patency of 5.1 months in these patients. No problems related to stent migration or brittleness have been encountered.

Occlusion during iliac angioplasty: a salvageable complication.

During transluminal dilation of the iliac artery, occlusion resulting from dissection occurred in four patients. In all four, the deteriorating clinical findings prompted surgical intervention. In three patients, Fogarty balloon catheters easily passed the occluded segments and specimens much the same as surgical endarterectomy specimens were retrieved. A clamp was used to retrieve the dissected portion of the vessel wall in the fourth patient. Three of four vessels have remained patent for 18 months, 18 months, and 6 months, respectively. One patient underwent bypass surgery 4 months after the occlusion episode for recurrent stenosis in a segment of vessel above the occluded segment, which had also been dilated during the same procedure. It is therefore possible in some cases to salvage vessels occluded during angioplasty, making it unnecessary to resort to aortofemoral or other type of bypass.

Duodenal perforation as a delayed complication of placement of a biliary endoprosthesis.

Duodenal perforation may occur at the time of insertion of a biliary endoprosthesis or following endoscopic manipulation of such a stent. The possibility of perforation as a late sequela of stent migration, after percutaneous placement of an endoprosthesis, however, has not been emphasized. In the authors' experience with a 12-F soft-stent endoprosthesis, duodenal perforation occurred in four of 50 patients following initially satisfactory stent placement. One intraperitoneal perforation necessitated immediate surgical intervention. The three retroperitoneal perforations were treated conservatively.

Antegrade ureteral stents: technical and catheter-related problems with polyethylene and polyurethane.

Antegrade placement of polyethylene and polyurethane stents was successfully achieved in 93 of 107 ureters (87 of 101 patients). These materials functioned adequately in 24 of 26 patients with indications for temporary stenting, including fistulas, strictures, and trauma caused by manipulation of calculi. Thirty of 61 patients with malignancy (49.2%) died within 6 months with their original stents in place; 12 survived to undergo elective cystoscopic stent replacement. Fifteen of the 61 patients had premature stent occlusions, which were treated by permanent nephrostomy in nine, replacement of the stent in five, and no further diversion in one patient with lymphoma. Encrustation and stent occlusion are problems during extended use of polyethylene and polyurethane stents. Long-term patency rates with newer stent materials remain to be documented and compared.

Radiological evaluation of the chronic venous stasis syndrome.

Chronic venous stasis is an extremely complex clinical syndrome of pain and changes in the skin that can involve the superficial, deep, and perforating veins. This syndrome is commonly referred to as "the postphlebitic syndrome," implying that thrombophlebitis is its sole etiology. To test this hypothesis, we performed ascending venography on 51 limbs of patients with the chronic venous stasis syndrome and demonstrated that 32 had no radiological evidence of recent or old thrombophlebitis. Instead, they had normal-appearing veins, suggesting primary incompetence of the deep and/or perforating venous valves rather than thrombophlebitis as the etiology. Since various operations have recently been proposed to correct or bypass malfunctioning valves, precise demonstration of pathological change is required to choose the appropriate procedure and to evaluate results. Descending venograms were combined with the ascending studies in 42 limbs for this purpose. In addition to outlining the abnormalities responsible for chronic venous stasis syndrome in individual cases, interesting conclusions regarding the syndrome itself were reached.

Placement of ureteral stents by antegrade and retrograde techniques.

In summary, ureteral stenting is an established urologic and radiologic procedure. The percutaneous antegrade approach performed by the radiologist and the retrograde route employed by the urologist have gained acceptance as valuable adjuncts in the management of patients with ureteral obstruction due to malignancy. Stents are widely used following ureteral surgery and percutaneous manipulations. They provide a route for urinary drainage while maintaining adequate ureteral caliber, so that healing of damaged ureters can take place.

Angiography in the in situ saphenous vein bypass.

In situ saphenous vein bypass is a technique of lower-extremity revascularization that is gaining popularity as an alternative to the reversed saphenous vein graft. In the latter, the saphenous vein is removed from its bed and reversed before arterial anastomosis. The former uses the vein in situ after the venous valves are made incompetent and the perforators are ligated. Only the proximal and distal ends of the vein are mobilized for anastomosis. The radiologist assists in the management of these patients by performing preoperative venography, intraoperative arteriography, and postoperative arteriography when required. Techniques of these procedures, along with normal and abnormal findings, are discussed.