Clinical outcomes of inferior vena cava filter placement in patients with renal vein anomalies.

BACKGROUND: To investigate the clinical outcomes in patients with renal vein anomalies who undergo inferior vena cava (IVC) filter placement. METHODS: Contrast-enhanced computed tomography images of 410 patients who underwent IVC filter placement were retrospectively reviewed to detect renal vein anomalies. Clinical outcomes involving de novo pulmonary embolism and worsening of renal function were compared between patients with the location of filters placed in relation to the anomalous renal veins versus not in relation to any renal veins. RESULTS: A total of 97 (23.7%) renal vein anomalies were identified: 62 (15.1%) multiple right renal veins, 23 (5.6%) circumaortic left renal veins, 10 (2.4%) retroaortic left renal veins, and 2 (0.5%) accessory left renal veins. Frequency of de novo pulmonary embolism in patients with circumaortic left renal veins who had filters placed at or in between the 2 left renal veins was not significantly different from patients who underwent infra- or suprarenal filter placement (5.9% [1/17] vs. 3.1% [12/387]; P = 0.433). The frequency of patients who had a >25% decrease in estimated glomerular filtration rate after IVC filter placement was not significantly different whether the filter was placed in an infrarenal location or at or above the level of the anomalous renal veins (11.0% [37/335] vs. 17.6% [6/34]; P = 0.261). CONCLUSIONS: Clinical outcomes involving the frequency of de novo pulmonary embolism and worsening of renal function are not dependent on location of IVC filter placement in patients with renal vein anomalies.

The conventional balloon-occluded retrograde transvenous obliteration procedure: indications, contraindications, and technical applications.

Transvenous obliteration of gastric varices can be performed from the systemic venous side (draining veins or shunts) or from the portal venous side (portal afferent feeders). Balloon-occluded transvenous obliteration from the systemic veins is referred to as balloon-occluded retrograde transvenous obliteration (BRTO) and balloon-occluded transvenous obliteration from the portal veins is referred to as balloon-occluded antegrade (anterograde) transvenous obliteration (BATO). BRTO is the conventional balloon-occluded transvenous obliteration procedure and BATO is considered an alternative or adjunctive approach. This is because, from a technical standpoint, the least invasive choice of access or approach for balloon-occluded transvenous obliteration of gastric varices is the traditional or conventional transrenal route. The objective of BRTO or BATO or both is complete obliteration of the gastric varices with preservation of the anatomical hepatopetal flow of the splenoportal circulation. This article reviews the indications, contraindications, and technical considerations of the conventional BRTO procedure. The indications of concomitant portal venous modulators such as splenic embolization or the creation of a transjugular intrahepatic portosystemic shunt or both are also discussed.

Incidence and complications of accidental cannulation of retroperitoneal veins during venography for inferior vena cava filter placement.

BACKGROUND: The purpose of this study was to evaluate the incidence and complications of accidental cannulation of retroperitoneal veins during venography for inferior vena cava (IVC) filter placement. METHODS: In total, 641 patients who underwent IVC filter placement were retrospectively reviewed. Incidence of accidental cannulation of retroperitoneal veins during venography (using 633 sheaths and 18 catheters, including 11 pigtail type and 7 end-hole-type catheters), along with the associated complications, were evaluated. RESULTS: The overall frequency of accidental cannulation of retroperitoneal veins was 5.4% (35 of 651) via venous approaches: 5.8% (24 of 411) via a right femoral approach, 3.9% (5 of 129) via a left femoral approach, and 5.4% (6 of 111) via a jugular approach. The most frequent veins cannulated were the ascending lumbar veins (4.6%, 25 of 540) via a femoral approach, and the median sacral vein (3.6%, 4 of 111) via a jugular approach. No significant difference in the frequency of accidental cannulation was observed between venography through sheaths and catheters (5.4% [n = 34] vs. 5.6% [n = 1; using an end-hole-type catheter]; P = 1.000). Injuries to 5 veins (0.8%), including 3 ascending lumbar veins, were observed. Inadvertent filter placement within the right ascending lumbar vein was observed in 1 patient (0.2%). CONCLUSIONS: Accidental cannulation of retroperitoneal veins during venography for IVC filter placement is an infrequent occurrence, and in this patient series did not result in negative clinical outcomes. However, operators should be aware of the risk of accidental cannulation to prevent avoidable complications such as venous injury or filter misplacement.

Balloon-occluded antegrade transvenous obliteration with or without balloon-occluded retrograde transvenous obliteration for the management of gastric varices: concept and technical applications.

Alternative routes for transvenous obliteration are sometimes resorted in the management of gastric varices. These alternative routes can be classified into A, portal venous access routes and B, systemic venous access routes. The portal venous approach to transvenous obliteration is called balloon-occluded antegrade transvenous obliteration (BATO) and is a collective definition, including 1-percutaneous transhepatic obliteration (PTO), 2-through an existing transjugular intrahepatic portosystemic shunt [(Trans-TIPS), and 3-trans-iliocolic vein obliteration (TIO)]. PTO is usually out of necessity; however, trans-TIPS approach is usually used out of serendipity (because the low-risk access route is there). The TIPS for the trans-TIPS BATO is not formed for mere access, but is done to create a TIPS or is done when there is a preexisting TIPS. The trans-TIPS approach can be resorted to in the United States in up to 19% of balloon-occluded retrograde transvenous obliteration (BRTO) cases. PTO is resorted to, out of necessity, in the United States and Japan in 10% of BRTO cases (2%-19% of BRTO cases) and can increase the technical and obliterative success rate of the transvenous obliteration procedure from 84%-98% to 98%-100%. The advantage of BATO as an adjunct to BRTO (combining a BRTO and BATO approach to obliterate the gastric varices) is not only limited to increasing the technical success rate of the obliterative procedure. BATO reduces the risk of overspill of the sclerosant from the gastric variceal system into the portal vein. Moreover, if the BATO is performed from a trans-TIPS approach, any overspill of the sclerosant mixture will partly (if not mostly) go through the patent TIPS to the systemic circulation (lung) rather than the intrahepatic portal vein branches (prevent portal vein embolization). This article discusses the clinical and technical applications, technical considerations, and the outcomes of BATO.

Comparison of technical success and complications of percutaneous transhepatic cholangiography and biliary drainage between patients with and without transplanted liver.

OBJECTIVE: The purpose of this study is to compare technical success and complications of percutaneous transhepatic cholangiography (PTC) and percutaneous transhepatic biliary drainage (PTBD) between patients with and without transplanted liver. MATERIALS AND METHODS: Between 2007 and 2011, 89 PTCs, including 34 PTBDs, in 87 patients with transplanted liver were attempted, and 131 PTCs, including 118 PTBDs, in 126 patients without transplanted liver were attempted. Technical success, diameters of the bile ducts, fluoroscopy time, and complications were statistically compared between the two groups. RESULTS: The technical success rate of PTC for transplanted liver was significantly lower than that for nontransplanted liver (88.8% vs 98.5%; p = 0.004). Consequently, the technical success rate of PTBD for transplanted liver was also significantly lower than that for nontransplanted liver (75.0% vs 95.8%; p < 0.001). The average diameters of the first branches and second branches of the bile ducts of transplanted liver were significantly smaller than those of nontransplanted liver (5.8 ± 3.4 mm vs 8.7 ± 3.9 mm for the first branches [p < 0.001]; and 3.7 ± 1.7 mm vs 5.8 ± 2.4 mm for the second branches [p < 0.001]). No significant difference of fluoroscopy time of unilateral successful PTBD was observed (21.8 ± 11.7 vs 19.3 ± 12.9 min; p = 0.372), and no significant difference of overall complication rates was observed (8.0% vs 8.7%; p = 1.000) between transplanted and nontransplanted liver. CONCLUSION: The technical success rates of PTC and PTBD for transplanted liver are slightly lower than those for nontransplanted liver because the bile ducts are smaller. There is no significant difference in complication rate.

Incidence of cholangitis and sepsis associated with percutaneous transhepatic biliary drain cholangiography and exchange: a comparison between liver transplant and native liver patients.

OBJECTIVE: The purpose of our study was to determine the rate of sepsis and cholangitis associated with percutaneous biliary drain cholangiography and subsequent drain exchanges and to compare the incidence of these complications between patients with liver transplants and those with native livers. MATERIALS AND METHODS: A retrospective review of 154 consecutive patients (100 with liver transplants and 54 with native livers) who underwent a total of 910 percutaneous biliary drain cholangiography examinations and exchanges (January 2005 to July 2008) was performed. Cholangitis was defined as fever (> 38.5°C) within 24 hours after the intervention, and sepsis included cholangitis in addition to hemodynamic instability. RESULTS: The overall incidence of cholangitis and sepsis after percutaneous biliary drain exchanges was 2.1% (n = 19/910 exchanges) and 0.4% (n = 4/910 exchanges), respectively. There was no statistically significant difference in complications between liver transplant patients versus nontransplant patients (p = 0.34 for cholangitis and p = 1.00 for sepsis). The mean hospital stay due to postprocedural complications was 2.4 days for observation and supportive treatment. None of these patients required an intensive care stay. Mean percutaneous biliary drain dwell time in liver transplant and nontransplant patients was 6.2 and 1.5 months, respectively. Transplant patients were significantly younger (54 versus 67 years; p << 0.05), male predominant (70% vs 52%, p = 0.035), and had more severe liver disease (12.2 vs 8.0 Model for End-Stage Liver Disease [MELD] scores; p << 0.05). CONCLUSION: Percutaneous biliary drain cholangiography and exchange is associated with a low rate of postprocedure cholangitis and sepsis. These complications require brief hospitalizations. Liver transplant patients do not have an increased risk of complications despite higher MELD scores and longer intubation periods.

Dual-tract transhepatic U-shaped hemodialysis inferior vena cava catheter: a feasibility study in a swine model.

PURPOSE: To evaluate the feasibility of establishing a U-shaped inferior vena cava (IVC) catheter entirely from a transhepatic approach and to determine the catheter caliber that would provide adequate flow for hemodialysis. MATERIALS AND METHODS: Three pigs (weight, 45-50 kg) were used. A peripheral right hepatic vein was accessed transhepatically by using a 22-gauge needle, and a 0.018-inch wire was passed into the hepatic veins and IVC. An accessory right hepatic vein was accessed from the IVC. A snare was deployed in the accessory vein and used as a target for a second transhepatic 22-gauge needle pass. A wire was snared through the second transhepatic tract, around into the IVC, and through the first transhepatic tract. The 0.018-inch wire was upsized to a 0.035-inch platform. Measurements where made to tailor a U-shaped catheter from simple 10.2- and 12-F tubes by cutting them longitudinally (single long side hole) along the length of the IVC segment. The U-shaped hemodialysis catheter was placed over the wire and positioned so that the catheter opening lay in the IVC. With use of a dialysis machine, pressures and flow tolerance at set flow rates (100, 200, 300, 350, and 400 mL/min) were tested. RESULTS: All pigs underwent and survived successful catheter placements. All 10.2- and 12-F catheters tolerated flow rates up to 350 and 400 mL/min, respectively. CONCLUSIONS: Establishing a U-shaped hemodialysis catheter with an entirely transhepatic approach is technically feasible. The 10.2-F U-shaped dialysis catheters provided a flow rate (>350 mL/min) that is appropriate for hemodialysis in human clinical settings.

Development of a new subclavian arterial infusion chemotherapy method for locally or recurrent advanced breast cancer using an implanted catheter-port system after redistribution of arterial tumor supply.

Locally or recurrent advanced breast cancers can receive arterial blood supply from various arteries, such as the internal thoracic artery (ITA), the lateral thoracic artery, and the other small arterial branches originating from the subclavian artery. Failure to catheterize and subsequent formation of collateral arterial blood supply from various arteries are some of the reasons why the response to conventional selective transarterial infusion chemotherapy is limited and variable. To overcome this problem, we developed a new subclavian arterial infusion chemotherapy method using an implanted catheter-port system after redistribution of arterial tumor blood supply by embolizing the ITA. We named this technique ("redistributed subclavian arterial infusion chemotherapy" (RESAIC)). Using RESAIC, patients can be treated on an outpatient basis for extended periods of time. Eleven patients underwent RESAIC, and the complete remission and partial response rate in 10 evaluable patients was 90%: complete remission [CR] n = 4, partial remission n = 4, stable disease n = 1, and not evaluable n = 1. Three of four patients with CR had no distant metastasis, and modified radical mastectomy was performed 1 month after conclusion of RESAIC. The resected specimens showed no residual cancer cells, and pathologically confirmed complete remission was diagnosed in each of these cases. Although temporary grade-3 myelosuppression was seen in three patients who were previously treated by systemic chemotherapy, there was no other drug-induced toxicity or procedure-related complications. RESAIC produced a better response and showed no major complications compared with other studies despite the advanced stage of the cancers.

Catheter thrombolysis of thrombosed hepatic arteries in liver transplant recipients: predictors of success and role of thrombolysis.

Hepatic artery thrombosis is an uncommon complication of liver transplantation. However, it is a major indication for re-transplantation. The use of transcatheter thrombolysis and subsequent surgical revascularization as a graft salvage procedure is discussed. Four of 5 cases (80%) were successful in re-establishing flow and uncovering underlying arterial anatomic defects. None were treated definitively by endoluminal measures due to an inability to resolve the underlying anatomic defects. However, 2 of 5 cases (40%) went on to a successful surgical revascularization and represent successful long-term outcome of transcatheter thrombolysis followed by definitive surgical revascularization. We conclude that, definitive endoluminal success cannot be achieved without resolving associated, and possibly instigating, underlying arterial anatomical defects. However, reestablishing flow to the graft can unmask underlying lesions as well as asses surrounding vasculature thus providing anatomical information for a more elective, better planned and definitive surgical revision.

Radiological reporting that combine continuous speech recognition with error correction by transcriptionists.

OBJECTIVE: We evaluated the usefulness of radiological reporting that combines continuous speech recognition (CSR) and error correction by transcriptionists. MATERIALS AND METHODS: Four transcriptionists (two with more than 10 years' and two with less than 3 months' transcription experience) listened to the same 100 dictation files and created radiological reports using conventional transcription and a method that combined CSR with manual error correction by the transcriptionists. We compared the 2 groups using the 2 methods for accuracy and report creation time and evaluated the transcriptionists' inter-personal dependence on accuracy rate and report creation time. We used a CSR system that did not require the training of the system to recognize the user's voice. RESULTS: We observed no significant difference in accuracy between the 2 groups and 2 methods that we tested, though transcriptionists with greater experience transcribed faster than those with less experience using conventional transcription. Using the combined method, error correction speed was not significantly different between two groups of transcriptionists with different levels of experience. CONCLUSION: Combining CSR and manual error correction by transcriptionists enabled convenient and accurate radiological reporting.

Inadvertent discontinuation of percutaneous nephrostomy catheters in adult native kidneys: incidence and percutaneous management.

PURPOSE: To evaluate the incidence and consequences of complete inadvertent percutaneous nephrostomy catheter discontinuation in native kidneys of adults. In addition, this study evaluated the success rate of nephrostomy tract recannulation. MATERIALS AND METHODS: Retrospective analysis was performed in adult patients who underwent percutaneous nephrostomy between January 2000 and December 2005. Patients' conditions were evaluated for complete inadvertent discontinuation of use of the nephrostomy catheters and success of subsequent recannulation procedures. Habitual discontinuation was defined by three catheter discontinuation episodes in one patient. Conditions of patients with inadvertent discontinuation were assessed for major complications before and after the recannulation, including the need for de novo nephrostomy to reestablish clinically needed access. The incidences of inadvertent discontinuation and primary assisted recannulation tract maintenance were calculated according to the Kaplan-Meier method. Successful versus unsuccessful recannulation procedures were compared for tract age, length of time the drain was out of the tract, and catheter diameter with use of the Mann-Whitney U test. RESULTS: A total of 283 patients underwent 325 percutaneous nephrostomies. The inadvertent catheter discontinuation rates at 6, 12, 24, and 36 months were 26%, 36%, 53%, and 62%, respectively. For the same time intervals, the primary recannulation assisted tract maintenance rates were 94%, 86%, 77%, and 72%, respectively. Habitual discontinuation was seen in 3.2% of the total population and 19.1% of discontinuation cases. The technical success rates of all and first-time recannulations were 85% and 74%, respectively. Tract maturity was the only variable that was statistically significant between successful and unsuccessful recannulations (P < .0001). A total of 3.5% of patients required new nephrostomies. CONCLUSION: Despite the high incidence of inadvertent discontinuation of nephrostomy catheters, the major complication rate was only 3.5%, indicating the efficacy of tract recannulation, especially in mature tracts.

Safety and efficacy of fluoroscopic versus ultrasound guidance for core liver biopsies in potential living related liver transplant donors: preliminary results.

PURPOSE: To describe and evaluate the safety and efficacy of fluoroscopically guided percutaneous liver biopsies in comparison with ultrasound (US)-guided percutaneous liver biopsies in potential living related liver donors. MATERIALS AND METHODS: Retrospective analysis of 133 consecutive preoperative workups of potential living related liver donors was performed. The subjects were treated from January 1999 through May 2002. Subjects were divided into those who underwent US-guided subcostal 18-gauge core liver biopsies (group I) and those who underwent fluoroscopically guided intercostal 18-gauge core liver biopsies (group II). Group II biopsies were performed in a manner similar to percutaneous transhepatic cholangiography. All samples obtained during the study period were reevaluated prospectively by a transplant pathologist blinded to guidance modality for sample adequacy (defined as >or=5 complete portal triads). Subjects were followed for 4 hours before discharge and afterward in the transplant clinic until donation. Subjects who did not donate organs were followed for at least 1 month. RESULTS: One hundred thirty-three potential donors were evaluated (55 for group I, 78 for group II). Mean follow-up was 1.7 months, and 77% of subjects donated. The mean numbers of needle passes were 2.1 and 2.3 for groups I and II, respectively. No major complications were encountered, and all subjects were discharged in 4 hours. Incidences of minor complications were 3.6% (vasovagal reactions) and zero for groups I and II, respectively. Sample adequacy rates were 100% and 99% for groups I and II, respectively. One case (1.8%) in group I, although pathologically adequate, had additional renal tissue. CONCLUSION: Fluoroscopically guided liver biopsy shows encouraging initial safety results and is as effective as US-guided liver biopsy in normal subjects.

Cystic beta2-microglobulin amyloidoma in a patient on long-term hemodialysis.

We report a patient with beta2 microglobulin amyloidosis (beta2M) in whom cystic tumors were seen in the bilateral axillary region. The patient was a 68-year-old woman who had been on hemodialysis for more than 20 years because of IgA nephropathy. Computed tomography-guided biopsy was performed to confirm the diagnosis. Congo red staining, beta2M immunohistochemistry, and electron microscopy examination of the biopsied sample showed extended beta2M deposits in the cystic tumor. beta2M-related amyloidosis in patients with long-term dialysis commonly presents as osteoarticular disease, although a soft-tissue pseudotumor, known as amyloidoma, has been reported. This is the first report in the English-language literature of amyloidosis presenting as bilateral axillary cystic tumors.

Elective transjugular intrahepatic portosystemic shunt creation for portal decompression in the immediate pretransplantation period in adult living related liver transplant recipient candidates: preliminary results.

PURPOSE: To evaluate (i) the efficacy of purposeful creation of transjugular intrahepatic portosystemic shunts (TIPS) before transplantation to optimize potential living related liver transplantation (LRLTx) and (ii) the efficacy of TIPS creation in this setting in reducing perioperative resource utilization. MATERIALS AND METHODS: Retrospective review was performed of the records of patients who underwent adult LRLTx with or without preoperative TIPS creation from October 2003 through April 2005. Patients were evaluated for preoperative parameters (Child-Pugh class, Model for End-stage Liver Disease score, Acute Physiology and Chronic Health Evaluation [APACHE] II score, and coagulation parameters), intraoperative parameters (blood transfusion requirements and operative time), and postoperative parameters (intensive care unit stay, hospital stay, and 30-day repeat operation and mortality rates). Comparison between the two treatment groups was made with the Mann-Whitney U test. Within the TIPS group, comparison of blood transfusion requirements was performed by one-way analysis of variance based on the degree of portosystemic gradient reduction after TIPS creation. RESULTS: Sixteen patients were included in the TIPS group, and 12 patients were included in the group without TIPS. Median time between TIPS and transplantation was 2 days. There was no statistical difference in the preoperative, intraoperative, and postoperative parameters between groups except for the APACHE II score (P<.002), which was higher in the TIPS group. Despite this, the outcome and postoperative hospital resource utilization were similar between groups. Intraoperative blood transfusion based on the degree of portosystemic gradient reduction after TIPS creation was not significantly different between groups. CONCLUSIONS: Newly created TIPS do not interfere with the intraoperative technical and perioperative clinical aspects of adult LRLTx. Preoperative TIPS creation before transplantation may reduce the postoperative morbidity and mortality seen in liver transplant recipients who have a greater APACHE II score at the outset of treatment.

Transhepatic dilation of anastomotic biliary strictures in liver transplant recipients with use of a combined cutting and conventional balloon protocol: technical safety and efficacy.

PURPOSE: To determine the safety and technical efficacy of a transhepatic dilation protocol involving the use of a combined cutting and conventional balloon protocol in the management of anastomotic biliary strictures in adult liver transplant recipients. MATERIALS AND METHODS: Retrospective review of adult transplant recipients undergoing transhepatic cutting balloon dilation for anastomotic biliary strictures was performed over a period of 8 months. Cutting balloon dilation was followed by conventional balloon dilation with use of a balloon with a diameter at least as large as that of the initial cutting balloon. Technically successful dilation was defined by improvement of the biliary stricture. A technically successful regimen was defined by a residual stenosis less than 30% after a maximum of three sessions. The technical results were stratified according to lesions treated for the first time and those with restenosis. Comparison among institutions in terms of published methods and technical results were made. RESULTS: Twenty-two patients with liver transplants underwent 49 cutting balloon dilation sessions as part of 27 regimens (1.8 sessions per regimen): 12 cases of primary treatment, 10 cases of restenosis, four for intraprocedural failures of conventional balloon dilation, and one for the latter two indications. Technical success rates of regimens for primary stenoses, restenoses, and all cases were 100%, 90%, and 93%, respectively. These results compare favorably with historic intrainstitutional results, which are 89%, 73%, and 85% for primary stenoses, restenoses, and all cases, respectively. In addition, no biliary ruptures or cases of major hemobilia were encountered. Minor hemobilia was encountered in 10% of cases. CONCLUSIONS: The use of commercially available cutting balloons augmented subsequently with larger conventional balloons is safe for transhepatic balloon dilation and can increase the technical success rate of percutaneous management of transplant biliary strictures.

Endoluminal management of arterioportal fistulae in liver transplant recipients: a single-center experience.

Transcatheter embolization of arterioportal fistulae in liver transplant recipients is restricted to symptomatic arterioportal fistulae. Angiograms of liver transplant recipients from a single university medical center were retrospectively reviewed. Hemodynamically significant arterioportal fistulae were defined as those exhibiting opacification of the main portal vein of the transplanted hepatic graft or its first order branch with or without portal venous changes by Doppler ultrasound imaging. Six arterioportal fistulae were found. Doppler ultrasound imaging detected 50% of all arterioportal fistulae and all 3 hemodynamically significant arterioportal fistulae. Three successful embolizations were performed. Follow-up (37 to 67 months) demonstrated patent hepatic arteries and no parenchymal ischemic changes with graft preservation. High-throughput arterioportal fistulae may require larger intrahepatic artery branch embolization. There is a window of opportunity for embolizing significant arterioportal fistulae before their progression to large symptomatic, high through-put arterioportal fistulae with their added risk of ischemic changes before and after embolization.

Dynamic MRI for distinguishing high-flow from low-flow peripheral vascular malformations.

OBJECTIVE: The purpose of our study was to assess the usefulness of dynamic MRI in distinguishing high-flow vascular malformations from low-flow vascular malformations, which do not need angiography for treatment. SUBJECTS AND METHODS: Between September 2001 and January 2003, 16 patients who underwent conventional and dynamic MRI had peripheral vascular malformations (six high- and 10 low-flow). The temporal resolution of dynamic MRI was 5 sec. Time intervals between beginning of enhancement of an arterial branch in the vicinity of a lesion in the same slice and the onset of enhancement in the lesion were calculated. We defined these time intervals as "artery-lesion enhancement time." Time intervals between the onset of enhancement in the lesion and the time of the maximal percentage of enhancement above baseline of the lesion within 120 sec were measured. We defined these time intervals as "contrast rise time" of the lesion. Diagnosis of the peripheral vascular malformations was based on angiographic or venographic findings. RESULTS: The mean artery-lesion enhancement time of the high-flow vascular malformations (3.3 sec [range, 0-5 sec]) was significantly shorter than that of the low-flow vascular malformations (8.8 sec [range, 0-20 sec]) (Mann-Whitney test, p < 0.05). The mean maximal lesion enhancement time of the high-flow vascular malformations (5.8 sec [range, 5-10 sec]) was significantly shorter than that of the low-flow vascular malformations (88.4 sec [range, 50-100 sec]) (Mann-Whitney test, p < 0.01). CONCLUSION: Dynamic MRI is useful for distinguishing high-flow from low-flow vascular malformations, especially when the contrast rise time of the lesion is measured.

Transhepatic balloon dilation of anastomotic biliary strictures in liver transplant recipients: the significance of a patent hepatic artery.

PURPOSE: To determine the significance of hepatic artery steno-occlusive disease on the patency of anastomotic biliary strictures in liver transplant recipients after transhepatic balloon dilation. MATERIALS AND METHODS: A retrospective review of records of all patients undergoing transhepatic balloon dilation for anastomotic biliary strictures after orthotopic liver transplantation was performed over an 8-year period. Patency of the anastomosis was based on subsequent cholangiography. The presence of hepatic artery steno-occlusive disease was determined by Doppler ultrasound and/or angiography. The anastomotic biliary stricture patency rates were calculated by the Kaplan-Meier method. RESULTS: Thirty-eight patients who had undergone liver transplants underwent 53 balloon dilations for anastomotic biliary strictures (nine patients for arterial disease, 26 patients had patent arteries and three patients had arteries of indeterminate patency). Eight of the 53 strictures treated (15%) were refractory to balloon dilation: 10.5% of first comers and 27% of restenotic lesions. Two of the 53 strictures treated (4%) had significant complications: hemobilia requiring blood transfusion and ductal rupture. One-year cumulative primary patency rates for anastomotic biliary strictures for patients with arterial disease, patent hepatic arteries, and all-comers were: 0%, 45% (P = .01), and 36%, respectively. One-year cumulative primary patency rates for choledocho-choledocal and choledocho-jejunal anstomoses in patients with patent arteries were 43% and 48%, respectively (P = .10). CONCLUSIONS: In the presence of hepatic artery disease there is a lower patency of anastomotic biliary strictures after balloon dilation. Imaging of the hepatic artery should be considered to stratify patients who will have a successful outcome.

Arc of buhler: incidence and diameter in asymptomatic individuals.

The purpose of this study was to determine the incidence and diameter of the Arc of Buhler by power injection digital subtraction angiography in asymptomatic patients. A retrospective evaluation of 120 combined celiac (CAx) and superior mesenteric artery (SMA) angiograms was carried out on potential live related liver transplant donors (asymptomatic patients) performed from January 1999 to May 2002. The diameter of the Arc of Buhler was calculated with reference to the 5 French catheters used to perform the diagnostic angiograms. It was considered hemodynamically significant if it preferential filled the branches of the other visceral vessel. An Arc of Buhler was identified in 4 patients (3.3%). All 4 patients had a patent gastroduodenal artery (GDA) and none of the 4 had a hemodynamically significant stenosis of either the SMA or the CAx. All Arcs of Buhler found measured less than 2.5 mm in diameter and half of them (2 of the 4) filled the CAx when power injecting the SMA and/or vice versa. There is a low incidence of Arc of Buhler in asymptomatic patients; however, 50% of those encountered were hemodynamically significant. When evaluating the Arc of Buhler by angiography in the setting of pathology, it is important to have a reference diameter and hemodynamic reference in the normal setting, particularly when the prospect of GDA ligation or embolization is entertained in the presence of CAx or SMA occlusion.

Hepatic artery stenosis in liver transplant recipients: primary treatment with percutaneous transluminal angioplasty.

PURPOSE: To evaluate the efficacy of hepatic artery percutaneous transluminal angioplasty (PTA) in the treatment of hepatic artery stenosis (HAS). MATERIALS AND METHODS: A retrospective analysis was performed of all cases of HAS documented by angiography from January 1995 to June 2003 at the authors' institution. Management was evaluated and long-term patency was documented by Doppler ultrasonography. The patency, restenosis, and hepatic artery thrombosis (HAT) rates were determined by the Kaplan-Meier method. The technical success of hepatic artery PTA was stratified according to the location of the stenoses relative to the anastomosis, as well as by the presence of associated hepatic arterial kinks. RESULTS: Thrombosis was seen in 65% +/- 13% of untreated HAS cases within 6 months. Stenotic lesions without associated arterial kinks had an improved technical success rate and a reduced complication rate of 94% and 10%, respectively, compared with lesions with associated hepatic arterial kinks treated with hepatic artery PTA (14% and 29%, respectively). The 1-year primary and primary assisted patency rates of hepatic artery PTA for all lesions were 44% +/- 12% and 60% +/- 11%, respectively, and were 65% +/- 10% and 80% +/- 8%, respectively, for lesions not associated with hepatic arterial kinks. The 1-year HAT rate and restenosis rate after hepatic artery PTA were 19% +/- 10% and 32% +/- 11%, respectively. The 1-year primary assisted patency rate for hepatic artery PTA with repeat PTA performed for restenosed lesions and surgical revascularization performed for failed PTA was 74% +/- 10%. CONCLUSIONS: Untreated HAS carries a high morbidity rate. Hepatic artery PTA can play a large role in the management of HAS by reducing the HAT rate more than threefold. With appropriate lesion selection, hepatic artery PTA will have better patency rates than those associated with hepatic artery stent placement.