Combined Percutaneous Transrenal and Transfemoral Endovascular Recanalization and Angioplastic Reconstruction of a Disrupted Transplant Renal Artery Stent: A Novel Salvage Technique.

Renal artery stenosis is the most common vascular complication following renal transplantation. Percutaneous endovascular transluminal angioplasty with stenting is the treatment of choice for clinically significant renal artery stenosis. The authors present a case describing a novel combined transrenal parenchyma and transfemoral approach to repairing a disrupted transplant renal artery stent. The patient's allograft renal artery stenosis was initially managed via the standard percutaneous approach, but during follow-up the stent became disrupted and crushed, causing partial occlusion of the renal artery. This was manifested by persistently elevated serum creatinine values, lower extremity edema, and four-medication hypertension. After a failed traditional percutaneous transfemoral attempt, the authors were able to successfully access the renal arterial system via a combined transrenal and transfemoral approach, using an upper-pole artery through the renal parenchyma. This transrenal approach used a 3 Fr system, allowing the authors to get a wire across the stent, which they were previously unable to do. With wire access, they performed a balloon angioplastic reconstruction to restore the stent's patency, resulting in a reduction in serum creatinine, lower extremity edema, and blood pressure. This technique avoided a potentially difficult reoperative repair without immediate complication and provides a method for vascular access to the renal arterial system in select patients.

Renal Transplant Arterial Stenosis Treated With Bare-Metal Versus Drug-Eluting Stents: Comparison of Treatment Outcomes.

INTRODUCTION: This study aims to evaluate outcomes of bare-metal stents (BMS) versus drug-eluting stents (DES) in patients who undergo stenting for transplant renal arterial stenosis. MATERIALS AND METHODS: We retrospectively reviewed records of renal transplantation patients who underwent transplant renal arterial stenting from September 2009 to September 2013. All stents greater than 5 mm were excluded to allow for equivalent comparison between the DES and BMS groups. Statistical comparisons were performed using a two-tailed Fischer exact test, and analysis of continuous variables was analyzed using a one-way analysis of variance. RESULTS: The final study population included a total of 18 patients who received either BMS or DES (11 and 7 patients, respectively) for transplant renal arterial stenosis. The most common indications for stenting were increasing creatinine level and abnormal Doppler velocities. There were more re-interventions with BMS (n = 4/11) than DES (n = 0/7), but the trend was not statistically significant (P = .12). Three patients who received BMS had a clinically significant decrease in blood pressure versus 4 in the DES group (P = .33). Six patients who received BMS had a clinically significant decrease in creatinine level versus 3 in the DES group (P = 1.0). CONCLUSION: There is an absolute but not statistically significant difference in the incidence of restenosis requiring repeat intervention between the BMS and DES groups. No difference was detected in clinical success as measured by decreases in blood pressure or creatinine. Future larger studies are needed to corroborate these findings.

MR imaging as the sole preoperative imaging modality for right hepatectomy: a prospective study of living adult-to-adult liver donor candidates.

OBJECTIVE: Our aim was to investigate the feasibility of MR imaging as a comprehensive preoperative imaging test for examination of liver donor candidates for adult-to-adult right lobe transplantation. SUBJECTS AND METHODS: Twenty-five consecutive donor candidates were examined at 1.5 T using a torso phased array coil with breath-hold T1- and T2-weighted imaging of the abdomen, MR cholangiography using T2-weighted turbo spin-echo imaging, and MR angiography and venography of the liver using two interpolated three-dimensional spoiled gradient-echo sequences (average dose of gadolinium contrast material, 0.17 mmol/kg). Images were interpreted for liver parenchymal and extrahepatic abnormalities; measurements of right and left lobe liver volumes; definition of hepatic arterial, portal venous, and hepatic venous anatomy; and definition of the biliary branching pattern. Findings were compared with those of conventional angiography in 13 patients, 11 of whom also had surgical findings for comparison. RESULTS: Nine patients were excluded as candidates for donation on the basis of MR imaging findings that included parenchymal or extrahepatic abnormalities in five patients, vascular anomalies in two, and biliary anomalies in three. Two patients who did not undergo surgery underwent conventional angiography that confirmed MR angiographic findings except for a small (<2 mm) accessory left hepatic artery missed on MR imaging. Of the nine patients who underwent successful right hepatectomy, all MR imaging findings were corroborated intraoperatively. In two patients, right hepatectomy was aborted at laparotomy because of intraoperative cholangiography findings; in one of them, the biliary finding was unsuspected on MR imaging. CONCLUSION: A comprehensive MR imaging examination has the potential to serve as the sole preoperative imaging modality for living adult-to-adult liver donor candidates provided improvements in definition of intrahepatic biliary anatomy can be achieved.

MR-guided needle aspiration biopsies of hepatic masses using a closed bore magnet.

PURPOSE: Our purpose was to assess the efficacy of MR-guided biopsies with a conventional superconducting MR scanner and describe the techniques used to achieve successful results. METHOD: Fourteen biopsies were completed under MR guidance in 11 patients. Seven patients with previously detected lesions were referred for biopsy under MR guidance when hepatic lesions were identified by MRI but not with prebiopsy noncontrast CT or ultrasound (US). Additionally referred for MR-guided biopsy were four patients in whom previous CT- or US-guided biopsies of focal lesions were nondiagnostic. A 22 gauge MR-compatible needle was used in each case. Lesions ranged in size from 8 to 32 mm. Eleven lesions (eight patients) were suspected of being hepatomas, and three lesions (three patients) were suspected of being metastases. RESULTS: Thirteen of 14 MR-guided biopsies (93%) were diagnostic. Hepatocellular carcinoma was confirmed in 6 of 11 lesions suspected of representing hepatoma. One lesion, in a patient treated with chemoembolization, demonstrated necrotic material. One lesion yielded nondiagnostic material despite repeated visualization of the needle tip in the target lesion. Three lesions demonstrated metastatic carcinoma. Benign hepatocytes were detected in three biopsy specimens. Seven of the lesions that were successfully biopsied measured < 2.5 cm in diameter. CONCLUSION: With use of a closed bore 1.5 T system, diagnostic MR-guided needle aspiration biopsies of hepatic masses and subcomponents, including small lesions (< 2.5 cm), can be successfully obtained.

Extension of a secondary adrenal neoplasm into the inferior vena cava.

Adrenal cortical carcinoma is well known to extend into the renal veins and inferior vena cava. It is less known that neoplasms metastatic to the adrenal might also extend into the renal vein and cava. Only a few reports in the literature document this extension. We report a case of metastatic neoplasm to the adrenal extending into the inferior vena cava.

Adrenal myelolipomas: CT appearance with tiny amounts of fat and punctate calcification.

Five cases of myelolipoma of the adrenal are presented which contained only tiny foci of fat along with areas of punctate calcification. This computed tomographic (CT) appearance is less common for this neoplasm and has only been described in three of 26 previously published CT cases of this adrenal tumor. The presence of even tiny amounts of fat in an adrenal mass should alert the radiologist to the probable diagnosis of myelolipoma. Small foci of calcification are also frequently associated.

Management of symptomatic renal angiomyolipomas by embolization.

Renal angiomyolipomas are benign tumors which occur commonly in association with tuberous sclerosis or as isolated lesions. Symptomatic angiomyolipomas, particularly those in patients with tuberous sclerosis, should be approached conservatively with the goal of preserving as much normal renal tissue as possible. We report 2 patients in whom selective embolization was used to achieve this goal.