Long-term clinical outcomes after endovascular management of ruptured pseudoaneurysm in patients undergoing pancreaticoduodenectomy

PURPOSE: Recent studies have analyzed the short-term clinical outcomes of ndovascular management. However, the long-term outcomes are unknown. This study aimed to investigate clinical outcomes after endovascular management for ruptured pseudoaneurysm in patients after pancreaticoduodenectomy (PD). METHODS: The medical records of 2,783 patients who underwent PD were retrospectively reviewed at a single center. Of 62 patients who received intervention after pseudonaeurysm rupture, 57 patients (91.9%) experienced eventual success of hemostasis. The patients were composed as follows: (embolization only [EMB], n = 30), (stent-graft placement only [STENT], n = 19) and (both embolization and stent-graft placement simultaneously or different times [EMB + STENT], n = 8). Long-term complications were defined as events that occur more than 30 days after the last successful endovascular treatment. RESULTS: Among 57 patients, short-term stent-graft related complications developed in 3 patients (5.3%) and clinical complication developed in 18 patients (31.5%). Nine (15.8%) had long-term stent-graft related complications, which involved partial thrombosis in 5 cases, occlusion in 3 cases and migration in 1 case. Except for 1 death, the remaining 8 cases did not experience clinical complications. The stent graft primary patency rate was 88.9% after 1 month, 84.2% after 1 year, and 63.2% after 2 years. Of 57 patients, 30 days mortality occurred in 8 patients (14.0%). CONCLUSION: After recovery from initial complication, most of patients did not experience fatal clinical complication during long-term follow-up. Endovascular management is an effective and safe management of pseudoaneurysm rupture after PD in terms of long-term safety.

Long-term outcomes after stent insertion in patients with early and late hepatic vein outflow obstruction after living donor liver transplantation

PURPOSE: The purpose of this study was to describe the long-term effects of stenting in patients with hepatic venous outflow obstruction (HVOO), who underwent living donor liver transplantation (LDLT). METHODS: Between January 2000 and December 2009, 622 adult patients underwent LDLT at our hospital, and of these patients, 21 (3.3%) were diagnosed with HVOO; among these patients, 17 underwent stenting. The patients were divided into early or late groups according to the time of their HVOO diagnoses (cutoff: 60 days after liver transplantation). RESULTS: The median follow-up period was 54.2 months (range, 0.5–192.4 months). Stent insertion was successful in 8 of 10 patients in the early group and 6 of 7 in the late group. The 5-year primary patency rates were 46% and 20%, respectively. In both groups, patients with recurrent HVOO at the beginning showed kinking confirmed by venography. Patients who carried their stents for more than 3 years maintained long-term patency. There was no significant difference in spleen size between groups; however, when the groups were compared according to whether they maintained patency, spleens tended to be smaller in the patency-maintained group. CONCLUSION: Unlike stenosis, if kinking is confirmed on venography, stenting is not feasible in the long term for patients with LDLT.

The role of scheduled second TACE in early-stage hepatocellular carcinoma with complete response to initial TACE

BACKGROUND/AIMS: We investigated the outcomes of early-stage hepatocellular carcinoma (HCC) patients who showed a complete response (CR) to initial transarterial chemoembolization (TACE), with a focus on the role of scheduled TACE repetition. METHODS: A total of 178 patients with early-stage HCC who were initially treated with TACE and showed a CR based on the modified Response Evaluation Criteria in Solid Tumors (mRECIST) criteria on one month follow-up computed tomography (CT) were analyzed. Among them, 90 patients underwent scheduled repetition of TACE in the absence of viable tumor on CT. RESULTS: During a median follow-up period of 4.6 years (range: 0.4-8.8 years), mortality was observed in 71 patients (39.9%). The overall recurrence-free and local recurrence-free survival rates at 1 year were 44.4% and 56.2%. In the multivariable model, scheduled repetition of TACE was an independent factor associated with survival (hazard ratio [95% confidence interval]: 0.56 [0.34-0.93], P=0.025). When stratified using Barcelona clinic liver cancer (BCLC) stage, scheduled repetition of TACE was associated with a favorable survival rate in BCLC stage A patients, but not in BCLC 0 patients. CONCLUSIONS: Scheduled repetition of TACE was associated with better survival for early-stage HCC patients showing a CR after initial TACE, especially in BCLC stage A patients.

Portal Vein Stenting for Delayed Jejunal Varix Bleeding Associated with Portal Venous Occlusion after Hepatobiliary and Pancreatic Surgery

OBJECTIVE: The study aimed to describe portal stenting for postoperative portal occlusion with delayed (≥ 3 months) variceal bleeding in the afferent jejunal loop. MATERIALS AND METHODS: Eleven consecutive patients (age range, 2–79 years; eight men and three women) who underwent portal stenting between April 2009 and December 2015 were included in the study. Preoperative medical history and the postoperative clinical course were reviewed. Characteristics of portal occlusion and details of procedures were also investigated. Technical success, treatment efficacy (defined as disappearance of jejunal varix on follow-up CT), and clinical success were analyzed. Primary stent patency rate was plotted using the Kaplan-Meier method. RESULTS: All patients underwent hepatobiliary-pancreatic cancer surgery except two children with liver transplantation for biliary atresia. Portal occlusion was caused by benign postoperative change (n = 6) and local tumor recurrence (n = 5). Variceal bleeding occurred at 27 months (4 to 72 months) and portal stenting was performed at 37 months (4 to 121 months), on average, postoperatively. Technical success, treatment efficacy, and clinical success rates were 90.9, 100, and 81.8%, respectively. The primary patency rate of portal stent was 88.9% during the mean follow-up period of 9 months. Neither procedure-related complication nor mortality occurred. CONCLUSION: Interventional portal stenting is an effective treatment for delayed jejunal variceal bleeding due to portal occlusion after hepatobiliary-pancreatic surgery.

Yttrium-90 Selective Internal Radiation Therapy with Glass Microspheres for Hepatocellular Carcinoma: Current and Updated Literature Review

Hepatocellular carcinoma is the most common primary liver cancer and it represents the majority of cancer-related deaths in the world. More than 70% of patients present at an advanced stage, beyond potentially curative options. Ytrrium-90 selective internal radiation therapy (Y90-SIRT) with glass microspheres is rapidly gaining acceptance as a potential therapy for intermediate and advanced stage primary hepatocellular carcinoma and liver metastases. The technique involves delivery of Y90 infused glass microspheres via the hepatic arterial blood flow to the appropriate tumor. The liver tumor receives a highly concentrated radiation dose while sparing the healthy liver parenchyma due to its preferential blood supply from portal venous blood. There are two commercially available devices: TheraSphere® and SIR-Spheres®. Although, Y90-SIRT with glass microspheres improves median survival in patients with intermediate and advanced hepatocellular carcinoma and has the potential to downstage hepatocellular carcinoma so that the selected candidates meet the transplantable criteria, it has not gained widespread acceptance due to the lack of large randomized controlled trials. Currently, there are various clinical trials investigating the use of Y90-SIRT with glass microspheres for treatment of hepatocellular carcinoma and the outcomes of these trials may result in the incorporation of Y90-SIRT with glass microspheres into the treatment guidelines as a standard therapy option for patients with intermediate and advanced stage hepatocellular carcinoma.

Transarterial chemoembolization versus resection for intermediate-stage (BCLC B) hepatocellular carcinoma

BACKGROUND/AIMS: Several studies have suggested that surgical resection (SR) can provide a survival benefit over transarterial chemoembolization (TACE) for hepatocellular carcinoma (HCC) at the intermediate stage according to the Barcelona Clinic Liver Cancer (BCLC) staging system. However, the criteria for SR remain to be determined. This study compared the long-term outcome of intermediate-stage HCC patients treated by either TACE or SR as a primary treatment modality, with the aim of identifying the patient subgroup that gained a survival benefit by either modality. METHODS: In total, 277 BCLC intermediate-stage HCC patients treated by either TACE (N=225) or SR (N=52) were analyzed. RESULTS: The overall median survival time was significantly better for SR than TACE (61 vs. 30 months, P=0.002). Decision-tree analysis divided patients into seven nodes based on tumor size and number, serum alpha-fetoprotein (AFP) level, and Child-Pugh score, and these were then simplified into four subgroups (B1-B4) based on similarities in the overall hazard rate. SR provided a significant survival benefit in subgroup B2, characterized by ‘oligo' (2-4) nodules of intermediate size (5-10 cm) when the AFP levels was <400 ng/ml, or ‘oligo' (2-4) nodules of small to intermediate size (<10 cm) plus a Child-Pugh score of 5 when the AFP level was ≥400 ng/mL (median survival 73 vs. 28 months for SR vs. TACE respectively; P=0.014). The survival rate did not differ significantly between SR and TACE in the other subgroups (B1 and B3). CONCLUSIONS: SR provided a survival benefit over TACE in intermediate-stage HCC, especially for patients meeting certain criteria. Re-establishing the criteria for optimal treatment modalities in this stage of HCC is needed to improve survival rates.

Changes in Arterioportal Shunts in Hepatocellular Carcinoma Patients with Portal Vein Thrombosis Who Were Treated with Chemoembolization Followed by Radiotherapy / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: In this study, we retrospectively investigated the prevalence of arterioportal (AP) shunts in hepatocellular carcinoma (HCC) patients with portal vein tumor thrombosis (PVTT) and evaluated the changes in AP shunts after chemoembolization followed by external beam radiation therapy (EBRT). MATERIALS AND METHODS: We analyzed 54 HCC patients with PVTT who were treated with chemoembolization followed by EBRT. EBRT was uniformly delivered at a total dose of 30 to 45 Gy (median, 35 Gy), with a daily dose of 2 to 4.5 Gy. Angiographic images of chemoembolization before and after radiation therapy (RT) were reviewed to investigate the AP shunt. RESULTS: During the initial session of chemoembolization, 33 of 54 patients (61%) had an AP shunt. After EBRT, 32 out of 33 patients had an additional session of chemoembolization and were evaluated for a change in the AP shunt. The AP shunt decreased in 20 of 32 patients (63%) after chemoembolization followed by EBRT. The 1-year calculated overall survival (OS) rate for all patients was 52.6% and the 2-year OS was 36.4%. The median OS in all patients was 13 months. Patients with AP shunt showed poorer median OS than those without AP shunt, but there was no statistically significant difference (median, 12 months vs. 17 months). CONCLUSION: The AP shunt frequently occurs in HCC patients with PVTT. This study suggests that a poor prognosis is associated with an AP shunt. Chemoembolization followed by RT may produce a decrease in AP shunts.

Transcatheter arterial chemoembolization and radiation therapy for treatment-naive patients with locally advanced hepatocellular carcinoma

PURPOSE: To evaluate the safety and efficacy of transcatheter arterial chemoembolization (TACE) followed by radiotherapy (RT) in treatment-naive patients with locally advanced hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Eligibility criteria were as follows: newly diagnosed with HCC, the Barcelona Clinic Liver Cancer stage C, Child-Pugh class A or B, and no prior treatment for HCC. Patients with extrahepatic spread were excluded. A total of 59 patients were retrospectively enrolled. All patients were treated with TACE followed by RT. The time interval between TACE and RT was 2 weeks as per protocol. A median RT dose was 47.25 Gy10 as the biologically effective dose using the alpha/beta = 10 (range, 39 to 65.25 Gy10). RESULTS: At 1 month, complete response was obtained in 3 patients (5%), partial response in 27 patients (46%), stable disease in 13 patients (22%), and progressive disease in 16 patients (27%). The actuarial one- and two-year OS rates were 60.1% and 47.2%, respectively. The median OS was 17 months (95% confidence interval, 5.6 to 28.4 months). The median time to progression was 4 months (range, 1 to 35 months). Grade 3 or greater liver enzyme elevation occurred in only two patients (3%) after RT. Grade 3 gastroduodenal toxicity developed in two patients (3%). CONCLUSION: The combination treatment of TACE followed by RT with two-week interval was safe and it showed favorable outcomes in treatment-naive patients with locally advanced HCC. A prospective randomized trial is needed to validate these results.

Radiofrequency Ablation Combined with Chemoembolization for Intermediate-Sized (3-5 cm) Hepatocellular Carcinomas Under Dual Guidance of Biplane Fluoroscopy and Ultrasonography

OBJECTIVE: To assess the technical feasibility and local efficacy of percutaneous radiofrequency ablation (RFA) combined with transcatheter arterial chemoembolization (TACE) for an intermediate-sized (3-5 cm in diameter) hepatocellular carcinoma (HCC) under the dual guidance of biplane fluoroscopy and ultrasonography (US). MATERIALS AND METHODS: Patients with intermediate-sized HCCs were treated with percutaneous RFA combined with TACE. RFA was performed under the dual guidance of biplane fluoroscopy and US within 14 days after TACE. We evaluated the rate of major complications on immediate post-RFA CT images. Primary technique effectiveness rate was determined on one month follow-up CT images. The cumulative rate of local tumor progression was estimated with the use of Kaplan-Meier method. RESULTS: Twenty-one consecutive patients with 21 HCCs (mean size: 3.6 cm; range: 3-4.5 cm) were included. After TACE (mean: 6.7 d; range: 1-14 d), 20 (95.2%) of 21 HCCs were visible on fluoroscopy and were ablated under dual guidance of biplane fluoroscopy and US. The other HCC that was poorly visible by fluoroscopy was ablated under US guidance alone. Major complications were observed in only one patient (pneumothorax). Primary technique effectiveness was achieved for all 21 HCCs in a single RFA session. Cumulative rates of local tumor progression were estimated as 9.5% and 19.0% at one and three years, respectively. CONCLUSION: RFA combined with TACE under dual guidance of biplane fluoroscopy and US is technically feasible and effective for intermediate-sized HCC treatment.

Multidisciplinary Approach with Prenatally Diagnosed Congenital Arteriovenous Fistulae Involving the Umbilical Vein: A Case Report / 대한주산의학회잡지

Congenital arteriovenous fistulae, especially those involving the umbilical vein, are extremely rare. Here we report a case of prenatally diagnosed multiple congenital arteriovenous fistulae forming a communication between the left hepatic and both epigastric arteries to the umbilical vein, which was successfully treated with coil embolization and surgery shortly after birth in order to prevent cardiac failure and pulmonary hypertension for the first time in Korea.

Ethanol Embolotherapy of Pelvic Arteriovenous Malformations: an Initial Experience

OBJECTIVE: We retrospectively assessed the results of performing ethanol embolization for pelvis arteriovenous malformations (AVMs). MATERIALS AND METHODS: During the past 10 years, eight patients (8 females, age range: 27-52 years) with AVMs in the pelvic wall (n = 3) and uterus (n = 5) underwent staged ethanol embolizations (range: 1-5, mean: 2.5) under general anesthesia. Ethanol embolization was performed by the use of the transcatheter and/or direct puncture techniques. Clinical follow-up was performed for all of the patients, and imaging follow-up was available for seven patients. The therapeutic outcomes were established by evaluating the clinical outcome of the signs and symptoms, as well as the degree of devascularization observed on post-procedural angiography. RESULTS: During the 20 sessions of ethanol embolization, the solitary transarterial approach was used 14 times, the transvenous approach was used three times and direct puncture was used once. For two patients, the transarterial and transvenous or direct puncture approaches were used together in one session. For four patients, ethanol and coils were used as embolic agents, and n-butyl cyanoacrylate (NBCA) and ethanol were used in one patient. Seven (88%) of eight patients were cured of their AVMs and one patient (12%) displayed improvement. Major complications were seen in two patients (25%). CONCLUSION: Ethanol embolization is effective for the treatment of pelvic arteriovenous malformations, though there is a chance of a major complication.

Percutaneous Transluminal Angioplasty of Renal Artery Fibromuscular Dysplasia: Mid-term Results

OBJECTIVE: To evaluate mid-term imaging, clinical follow-up, and restenosis rates from patients that had undergone percutaneous transluminal renal artery angioplasty (PTRA) for symptomatic renal artery fibromuscular dysplasia (FMD). MATERIALS AND METHODS: Between March 1999 and July 2006, 16 consecutive renal artery FMD patients underwent PTRA for poorly controlled hypertension. The patients were enrolled into this retrospective study after receiving 19 primary and four secondary PTRAs in 19 renal artery segments. Follow-up monitoring of blood pressure, use of antihypertensive medication, and the serum creatinine level after PTRA were assessed at 1, 3, 6, 9, 12 months, and each following year. The degree of restenosis was evaluated with computed tomographic angiography (CTA) after PTRA at 6, 12 months, and every year if possible. Technical and clinical success rates for the treatment of FMD, and restenosis rates for the renal artery were evaluated. RESULTS: The technical success rate for primary PTRA was 79% (15/19) and the complication rate was 16% (3/19). Hypertension improved in 80% (12/15) of the patients after four weeks follow-up, and was finally cured or improved in 93% (14/15) during the mean follow-up period of 23.6 months. There was a cumulative 22% (4/18) restenosis rate during the follow-up period. All of the patients were treated with a second PTRA without complications and all of the patients were cured of hypertension after the second PTRA. CONCLUSION: Percutaneous transluminal renal artery angioplasty for clinically symptomatic renal FMD is technically and clinically successful and safe to perform. For all patients with restenosis, there was a good response after undergoing a second PTRA.

Peripheral Arteriovenous Malformations with a Dominant Outflow Vein: Results of Ethanol Embolization

OBJECTIVE: To assess retrospectively the treatment results of ethanol embolization of peripheral arteriovenous malformations (AVMs) with a dominant outflow vein (DOV). MATERIALS AND METHODS: Nineteen patients who had peripheral AVMs with a DOV were enrolled in this study (mean age, 29.7 years; range, 15-42 years). Fifty-one ethanol embolizations (mean, 2.7; range, 1-8) were performed by direct puncture (n = 29), the transarterial approach (n = 13), the transvenous approach (n = 5), or a combination of methods (n = 4) under general anesthesia. Coil and/or core-removed guide wire embolization of the DOV or another flow occlusion technique (i.e., use of an external pneumatic pressure cuff) to achieve vascular stasis were required in all patients during ethanol embolization. Clinical follow-up (mean, 22.2 months; range, 1-53 months) was performed for all patients, and imaging follow-up (mean, 22.1 months; range, 2-53 months) from the last treatment session was performed for 14 patients. The therapeutic outcome (cure, improvement, no change, or aggravation) was assessed according to the clinical response and the degree of devascularization at angiography. RESULTS: Ethanol embolization was considered as an effective procedure in all patients. Thirteen (68%) of 19 patients were cured and six displayed improvement. Three of six patients with improvement needed further treatment sessions for residual AVMs. Four patients (21%) experienced a total of eight complications. Five complications (three events of a distal embolism and one event each of a urinary bladder necrosis and a brain infarct related to the accidental cannulation of the common carotid artery during insertion of the Swan-Ganz catheter) were major and three complications (skin necrosis) were minor. CONCLUSION: Peripheral AVMs with a DOV can be effectively treated with a high cure rate by the use of ethanol embolization alone or in conjunction with the use of coil and/or core-removed guide wire embolization.

The Short-Term Effects of Balloon-Occluded Retrograde Transvenous Obliteration, for Treating Gastric Variceal Bleeding, on Portal Hypertensive Changes: a CT Evaluation

OBJECTIVE: We wanted to evaluate the short-term effects of balloon-occluded retrograde transvenous obliteration (BRTO) for treating gastric variceal bleeding, in terms of the portal hypertensive changes, by comparing CT scans. MATERIALS AND METHODS: We enrolled 27 patients who underwent BRTO for gastric variceal bleeding and they had CT scans performed just before and after BRTO. The pre- and post-procedural CT scans were retrospectively compared by two radiologists working in consensus to evaluate the short-term effects of BRTO on the subsequent portal hypertensive changes, including ascites, splenomegaly, portosystemic collaterals (other than gastrorenal shunt), the gall bladder (GB) edema and the intestinal wall edema. Statistical differences were analyzed using the Wilcoxon signed rank test and the paired t-test. RESULTS: Following BRTO, ascites developed or was aggravated in 22 (82%) of 27 patients and it was improved in two patients; the median spleen volumes increased from 438.2 cm3 to 580.8 cm3, and based on a 15% volume change cut-off value, splenic enlargement occurred in 15 (56%) of the 27 patients. The development of new collaterals or worsening of existing collaterals was not observed in any patient. GB wall edema developed or was aggravated in four of 23 patients and this disappeared or improved in five; intestinal wall edema developed or was aggravated in nine of 27 patients, and this disappeared or improved in five. Statistically, we found significant differences for ascites and the splenic volumes before and after BRTO (p = 0.001 and p < 0.001, respectively) CONCLUSION: Some portal hypertensive changes, including ascites and splenomegaly, can be aggravated shortly after BRTO.

Efficacy of Femoral Vascular Closure Devices in Patients Treated with Anticoagulant, Abciximab or Thrombolytics during Percutaneous Endovascular Procedures

OBJECTIVE: This study assessed the outcomes of using vascular closure devices following percutaneous transfemoral endovascular procedures in the patients who were treated with heparin, abciximab or thrombolytics (urokinase or t-PA) during the procedures. MATERIALS AND METHODS: From March 28, 2003 to August 31, 2004, we conducted a prospective and randomized study in which 1,676 cases of 1,180 patients were treated with one of the two different closure devices (the collagen plug device was Angio-SealTM; the suture-mediated closure device was The Closer STM) at the femoral access site after instituting percutaneous endovascular procedures. Among the 1,676 cases, 108 cases (the drug group) were treated with heparin only (n = 94), thrombolytics only (n = 10), heparin and thrombolytics (n = 3), or abciximab and thrombolytics (n = 1) during the procedures; 1,568 cases (the no-drug group) were treated without any medication. We compared the efficacy and complications between the two groups. Of the drug group, 42 cases underwent arterial closures with the collagen plug devices and 66 cases underwent arterial closures with the suture-mediated closure devices. We also compared the efficacy and complications between these two groups. RESULTS: The immediate hemostasis rates were 92.9% (1,456/1,568) in the no-drug group and 91.7% (99/108) in the drug group. Early complications occurred in four cases of the drug group. These included two episodes of rebleeding with using the Closer S, which required manual compression for at least 10 minutes, and two episodes of minor oozing with using one Angio-Seal and one Closer S, which required two hours of additional bed rest. There was no late complication. So, the total success rates were 90.8% (1,423/1,568) in the no-drug group and 88.0% (95/108) in the drug group. These results were not significantly different between the two groups (p = 0.34). In the drug group, the difference of the successful hemostasis rate between the collagen plug devices and the suture-mediated devices was also not statistically significant (92.9% vs. 84.8%, respectively; p = 0.21). CONCLUSION: Arterial closure of the femoral access site with using vascular closure devices is both safe and effective, even in the patients who received heparin, abciximab or thrombolytics.

Percutaneous Treatment of Failed Native Dialysis Fistulas: Use of Pulse-Spray Pharmacomechanical Thrombolysis as the Primary Mode of Therapy

OBJECTIVE: To determine the efficacy and outcome of percutaneous treatment in restoring the function of failed native arteriovenous fistulas (AVFs) where pulse-spray pharmacomechanical thrombolysis was used as the primary mode of therapy. MATERIALS AND METHODS: From June 2001 to July 2005, 14 patients who had thrombosis of native AVFs underwent percutaneous restoration following 20 episodes of thrombosis. These included 6 repeated episodes in one forearm AVF and two episodes in another forearm AVF. All patients except one were treated with urokinase injection utilizing the pulse-spray technique and had subsequent balloon angioplasty. One patient was treated by percutaneous angioplasty alone. We retrospectively evaluated the feasibility of percutaneous treatment in restoring the function of the failed AVFs. The primary and secondary patencies were calculated by using a Kaplan-Meier analysis. RESULTS: Both technical and clinical success were achieved in 15 (75%) of 20 AVFs. Four of the five technical failures resulted from a failure to cross the occluded segment. One patient refused further participation in the trial through a brachial artery access following failure to cross the occluded segment via an initial retrograde venous puncture. There were no major precedure related complications observed. Including the initial technical failures, primary patency rates at six and 12 months were 64% and 55%, respectively. Secondary patency rates at six and 12 months were 71% and 63%, respectively. CONCLUSION: Pulse-spray pharmacomechanical thrombolysis for treatment of the thrombosed AVFs is safe, effective and durable. This procedure should be considered as an option for the management of failed AVFs prior to surgical intervention.

Subintimal Angioplasty in the Treatment of Chronic Lower Limb Ischemia

OBJECTIVE: To present our experience with subintimal angioplasty (SA) for treatment of chronic lower limb ischemia (CLLI) and to assess its effectiveness and durability. MATERIALS AND METHODS: From April 2003 through June 2005, we treated 40 limbs in 36 patients with CLLI by SA. Balloons with or without secondary stent placement appropriate in size to the occluded arteries were used for SA of all lesions, except for iliac lesions where primary stent placement was done. The patients were followed for 1-23 months by clinical examination and color Doppler ultrasound and/or CT angiography. Technical results and outcomes were retrospectively evaluated. The presence of a steep learning curve for performance of SA was also evaluated. Primary and secondary patencies were determined using Kaplan-Meier analysis. RESULTS: Technical success was achieved in 32 (80%) of 40 limbs. There was no statistical difference between technical success rates of 75% (18/24) during the first year and 88% (14/16) thereafter. There were four complications (10%) in 40 procedures; two arterial perforations, one pseudoaneurysm at the puncture site, and one delayed hematoma at the SA site. Excluding initial technical failures, the primary patency rates at six and 12 months were 68% and 55%, respectively. Secondary patency rates at six and 12 months were 73% and 59%, respectively. CONCLUSION: Subintimal angioplasty can be accomplished with a high technical success rate. It should be attempted in patients with CLLI as an alternative to more extended surgery, or when surgical treatment is not recommended due to comorbidity or an unfavorable disease pattern.

Stent Placement for Chronic Iliac Arterial Occlusive Disease: the Results of 10 Years Experience in a Single Institution

OBJECTIVE: We wanted to retrospectively evaluate the long-term therapeutic results of iliac arterial stent placement that was done in a single institution for 10 years. MATERIALS AND METHODS: From May 1994 to April 2004, 206 patients who underwent iliac arterial stent placement (mean age; 64+/-8.8) were followed up for evaluating the long term stent patency. Combined or subsequent bypass surgery was performed in 72 patients. The follow up period ranged from one month to 120 months (mean; 31+/-25.2 months). The factors that were analyzed for their effect on the patency of stents were age, the stent type and diameter, the lesion site, lesion shape, lesion length, the Society of Cardiovascular and Interventinal Radiology criteria, the total run off scores, the Fontaine stage and the cardiovascular risk factors (diabetes mellitus, hypertension and smoking). Follow-up included angiography and/or CT angiography, color Doppler sonography and clinical evaluation with the ankle-brachial index. RESULTS: Two hundred and eighty-four stents were placed in 249 limbs of 203 patients. The technical success rate was 98% (203/206). The primary patency rates of the stents at 3, 5, 7 and 10 year were 87%, 83%, 61% and 49%, respectively. One hundred seventy-seven patients maintained the primary stent patency until the final follow up and 26 patients showed stenosis or obstruction during the follow up. Secondary intervention was performed in thirteen patients. Lesions in the external iliac artery (EIA) or lesions in both the common iliac artery (CIA) and EIA were a poor prognostic factor for stent patency. The run off score and stent diameter also showed statistically significant influence on stent patency. The overall complication rate was 6%. CONCLUSION: Iliac arterial stent placement is a safe treatment with favorable long term patency. Lesions in the EIA or lesions in both the EIA and CIA, poor run off vessels and a stent having the same or a larger diameter than 10 mm were the poor prognostic factors for long term stent patency.

Perfusion MR Imaging: Clinical Utility for the Differential Diagnosis of Various Brain Tumors

OBJECTIVE: To determine the utility of perfusion MR imaging in the differential diagnosis of brain tumors. MATERIALS AND METHODS: Fifty-seven patients with pathologically proven brain tumors (21 high-grade gliomas, 8 low-grade gliomas, 8 lymphomas, 6 hemangioblastomas, 7 metastases, and 7 various other tumors) were included in this study. Relative cerebral blood volume (rCBV) and time-to-peak (TTP) ratios were quantitatively analyzed and the rCBV grade of each tumor was also visually assessed on an rCBV map. RESULTS: The highest rCBV ratios were seen in hemangioblastomas, followed by high-grade gliomas, metastases, low-grade gliomas, and lymphomas. There was no significant difference in TTP ratios between each tumor group (p<0.05). At visual assessment, rCBV was high in 17 (81%) of 21 high-grade gliomas and in 4 (50%) of 8 low-grade gliomas. Hemangioblastomas showed the highest rCBV and lymphomas the lowest. CONCLUSION: Perfusion MR imaging may be helpful in the differentiation of thevarious solid tumors found in the brain, and in assessing the grade of the various glial tumors occurring there.

Diffusion MR Imaging in Patients with Intracranial Tumors

PURPOSE: To assess the usefulness of diffusion-weighted MR imaging in patients with intracranial tumors. MATERIALS AND METHODS: Using the single-shot spin echo EPI technique on a 1.5T unit and two gradient steps(b values of 0, 900 s/mm2), diffusion-weighted MR images (DW-MRI) of 76 patients with various intracranial tumors including high-grade glioma (n=20), meningioma (n=15), metastasis(n=14), lymphoma (n=6), low-grade glioma (n=5), schwannoma (n=4), cerebellar hemangioblastoma (n=3), - and others- were obtained. The signal intensity of each tumor was visually assessed as one of four grades, and this and apparent diffusion coefficient(ADC) were analyzed in the solid and cystic portions of tumors, normal gray matter, white matter and CSF. RESULTS: Lymphomas, metastases, meningiomas, and high- and low-grade gliomas showed low ADC values in increasing order. Tumors showing high signal intensity on DW-MRI had low ADC values. Visual assessment whowed that solid portions of high-grade gliomas were significantly more hyperintense than those of low-grade gliomas. There was, however, no significant difference in ADCs between high- and low-grade gliomas. Lymphoma a and metastases showed significantly higher signal intensities on DW-MRI and lower ADCs than did high-grade gliomas. There were significant differences in signal intensities, as seen on DW-MRI, and in ADCs, between metastatic adenocarcinomas and non-adenocarcinomas. Schwannomas and cerebellar heman-gioblastomas showed low signal intensities and high ADC values. CONCLUSION: DW-MRI appears to provide an additional means of examining intracranial tumors, not available with conventional MRI, and may thus be helpful in the grading of gliomas and the differential diagnosis of some intracranial tumors.