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OBJECTIVE: To assess the two-year treatment outcomes of chemoembolization with drug-eluting embolics (DEE) for nodular hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This study was a prospective, multicenter, registry-based, single-arm trial conducted at five university hospitals in Korea. Patients were recruited between May 2011 and April 2013, with a target population of 200. A DC Bead loaded with doxorubicin was used as the DEE agent. Patients were followed up for two years. Per-patient and per-lesion tumor response analysis, per-patient overall survival (OS) and progression-free survival (PFS) analysis, and per-lesion tumor control analysis were performed. RESULTS: The final study population included 152 patients, with 207 target lesions for the per-lesion analysis. At one-month, six-month, one-year, and two-year per-patient assessments, complete response (CR) rates were 40.1%, 43.0%, 33.3%, and 19.6%, respectively. The objective response (OR) rates were 91.4%, 55.4%, 35.1%, and 19.6%, respectively. The cumulative two-year OS rate was 79.7%. The cumulative two-year PFS rate was 22.4% and the median survival was 9.3 months. In multivariable analysis, the Child-Pugh score (p = 0.019) was an independent predictor of OS, and tumor multiplicity (p < 0.001), tumor size (p = 0.020), and Child-Pugh score (p = 0.006) were independent predictors of PFS. In per-lesion analysis, one-month, six-month, one-year and two-year CR rates were 57.5%, 58.5%, 45.2%, and 33.3%, respectively, and the OR rates were 84.1%, 65.2%, 46.6%, and 33.3%, respectively. The cumulative two-year per-lesion tumor control rate was 36.2%, and the median time was 14.1 months. The Child-Pugh score (p < 0.001) was the only independent predictor of tumor control. Serious adverse events were reported in 11 patients (7.2%). CONCLUSION: DEE chemoembolization for nodular HCCs in the Korean population showed acceptable survival, tumor response, and safety profiles after a two-year follow-up. Good liver function (Child-Pugh score A5) was a key predictor of per-patient OS, PFS, and per-lesion tumor control.

Concurrent intra-arterial chemotherapy and radiotherapy (iA-CCRT) can increase the response rate in hepatocellular carcinoma (HCC), but may cause a higher toxicity. We conducted this Phase I study to investigate the dose-limiting toxicity of iA-CCRT for HCC. In total, 52.5 Gy in 25 fractions was prescribed as planning target volume (PTV) 1 at dose level 1. The dose escalation was 0.2 Gy per fraction and up to 2.5 Gy, with 62.5 Gy at level 3. Concurrent intra-arterial 5-fluorouracil was administered during the first and fifth weeks of radiotherapy (RT). Toxicities were graded using the Common Toxicity Criteria for Adverse Events, version 4.0. Results: Seventeen patients with HCC were analyzed: four at dose level 1, 6 at level 2, and 7 at level 3. The mean irradiated dose administered to the uninvolved liver at each dose level was 21.3, 21.6, and 18.2 Gy, respectively. There was no grade &ge, 3 gastrointestinal toxicity, two patients experienced grade 3 hyperbilirubinemia. All patients had Child-Pugh class A disease, but 3 patients developed class B disease after iA-CCRT. During a median follow-up of 13 months, the median progression-free survival (PFS) and overall survival (OS) were 10 and 22 months, respectively. Patients treated at dose level 3 showed improved PFS and OS. Conclusions: Radiation dose escalation of iA-CCRT did not cause any significant toxicities in patients with advanced HCC. Further large-scale studies with long-term follow-up are needed to determine the efficacy and feasibility of higher doses of iA-CCRT.

Objectives Non-surgical methods have high success rates for treating benign biliary strictures (BBSs), but treatment of proximal strictures is difficult. Recent studies have reported that fully covered self-expandable metal stents (FCSEMSs) are useful for treating refractory BBSs. We investigated the efficacy of a short and removable FCSEMS with an anti-migration design for treatment of proximal BBSs. Methods Fully covered self-expandable metal stents were inserted endoscopically in patients with BBSs after living donor liver transplantation (LDLT). Each FCSEMS was initially maintained for 3 months and subsequently exchanged every 3 months until the stricture resolved. Adverse events and stricture recurrence after FCSEMS removal were assessed during follow-up. Results A total of 63 patients with a median age of 57 years were enrolled in this study; 50 were male. The most common underlying disease was hepatocellular carcinoma and the previous operation was LDLT. The mean duration from surgery to diagnosis of stricture was 8.5 months, and the mean stent indwelling time was 4.2 months. The technical success and stricture resolution rate were 100%. The recurrence rate was 23.8% and the adverse event rate was 12.7%. All stents were removable, and asymptomatic stent migration was observed in four patients (6.4%). Conclusions The newly designed FCSEMS is effective in the treatment of proximal BBSs after LDLT.

This study compared the efficacy of a percutaneous transhepatic cholangioscopy (PTCS) catheter and a fully covered self-expandable metal stent (FCSEMS) for maintaining biliary tract patency after magnetic compression anastomosis (MCA).This study included patients with completely obstructed benign biliary stricture (BBS), which was resolved by MCA and subsequent insertion of a PTCS catheter or FCSEMS. We compared the restenosis-free time after removal of the PTCS catheter or FCSEMS, and the rate of complications.A total of 49 patients were analyzed. The mean ages of the patients in these groups were 50.1 and 49.6 years, respectively. The predisposing conditions causing complete BBS were liver transplantation (n = 38), abdominal surgery (n = 10) and trauma (n = 1). The mean indwelling durations were 176 and 128 days in the PTCS catheter and FCSEMS groups, respectively. The mean follow-up duration after removal of the PTCS catheter and FCSEMS were 2259 and 680.5 days, respectively. Three patients in the PTCS group and three patients in the FCSEMS group experienced stricture relapse. The mean duration between recurrence and stent removal were 924 and 265 days, respectively, and the numbers of stricture-free days did not differ significantly between the two groups. The adverse event rate did not differ significantly between the PTCS and FCSEMS groups (50% vs. 24.2%, respectively).FCSEMSs have an efficacy and safety similar to those of PTCS catheters for maintaining biliary tract patency after MCA, but are more convenient for patients.

Inspissated bile syndrome (IBS) is a relatively rare condition. Many treatment options are available, including medication, surgery, and surgical interventions, such as insertion of cholecystostomy drain, endoscopic retrograde cholangiopancreatography, internal biliary drainage, and percutaneous transhepatic biliary drainage (PTBD). We herein report the first case of IBS that was successfully treated with PTBD in a two-month-old infant in Korea. PTBD was initiated on postnatal day 72. On postnatal day 105, we confirmed complete improvement and successfully removed the catheters. This report suggests that PTBD is a viable and safe treatment option for obstructive jaundice in very young infants.

Purpose To assess the efficacy and safety of transcatheter arterial chemoembolization with drug-eluting embolic (DEE) agents for nodular hepatocellular carcinoma (HCC). Materials and Methods The study design was a prospective multicenter registry-based, single-arm clinical trial that included 152 patients. One hundred three (67.8%) had a Child–Pugh class/score of A5, 114 (75.0%) had a performance status of 0, and 77 (50.7%) had Barcelona Clinic Liver Cancer (BCLC) stage A disease. The DEE chemoembolization procedures were performed with DC Bead particles loaded with doxorubicin solution. The primary endpoint of the study was 6-month tumor response assessed per modified Response Evaluation Criteria In Solid Tumors. Secondary endpoints were treatment safety and overall survival. Results At 1-month posttreatment assessment, complete response (CR) and objective response (OR; ie, CR or partial response) rates were 40.1% and 91.4%, respectively. At 6-month assessment, 121 patients remained for analysis, and CR and OR rates were 43.0% and 55.4%, respectively. The cumulative progression-free survival (PFS) rate at 6 months was 65.0%. Child–Pugh score, tumor multiplicity, and tumor size were independent predictors of PFS ( P = .020, P = .029, and P = .001, respectively). There was no 30-day mortality. The overall 6-month survival rate was 97.4%. There were no grade 4 adverse events or laboratory changes. Serious adverse events were reported in 7.2% of patients, and persistent deterioration of liver function was observed in 3.9%. Prominent biliary injury was demonstrated in 19.7% of patients. No liver abscess was observed. Conclusions DEE chemoembolization for nodular HCC had an acceptable safety profile and acceptable 6-month tumor response and survival rates.

Background: Recently, there has been an increase in clinical success rates using nonsurgical methods to resolve anastomotic biliary strictures (ABSs) that develop after liver transplantation (LT). However, some strictures are particularly refractory and cannot be completely resolved by an endoscopic or percutaneous procedure. Consequently, the aim of this study was to examine the feasibility and efficacy of using a newly designed fully covered self-expandable metal stent (FCSEMS) to resolve refractory ABS. Methods: A total of 35 patients with an ABS that developed after LT, but could not be resolved by an endoscopic or percutaneous procedure, were included in this study. FCSEMSs were positioned endoscopically and removed after 2–3 months. After stent removal, the patients were followed to assess complications, including re-stenosis. Results: The mean period from LT to stricture was 13.7 months, and the mean duration of the stricture was 31.8 months. The type and mean number of procedures previously attempted were endoscopic retrograde cholangiopancreatography (ERCP) (9.1 ± 5.1) in 19 patients and percutaneous transhepatic biliary drainage (9.2 ± 4.8) in 16 patients. All patients had successful FCSEMS insertions and removals; the mean stent indwelling time was 3.2 months. The mean follow-up period was 18.7 months (range: 6.4–37.8 months). Stricture recurrence was observed in 6 of 29 patients (recurrence rate: 20.7%). The anastomotic stricture resolved with the FCSEMS insertion in 29 of 35 patients (clinical success rate: 82.9%). Conclusions: The newly designed FCSEMS is a potentially feasible and effective treatment for anastomotic strictures that develop after LT but are not amenable to treatment by conventional procedures.

OBJECTIVE To evaluate retrospectively the clinical effectiveness of FlightPlan for Liver (FPFL), an automated tumor-feeding artery detection software in cone-beam CT angiography (CBCTA), in identifying tumor-feeding arteries for the treatment of hepatocellular carcinoma (HCC) using three different segmentation sensitivities. MATERIALS AND METHODS The study included 50 patients with 80 HCC nodules who received transarterial chemoembolization. Standard digital subtracted angiography (DSA) and CBCTA were systematically performed and analyzed. Three settings of the FPFL software for vascular tree segmentation were tested for each tumor: the default, Group D; adjusting the proportion of segmented tumor area between 30 to 50%, Group L; and between 50 to 80%, Group H. RESULTS In total, 109 feeder vessels supplying 80 HCC nodules were identified. The negative predictive value of DSA, FPFL in groups D, L, and H was 56.8%, 87.7%, 94.2%, 98.5%, respectively. The accuracy of DSA, FPFL in groups D, L, and H was 62.6%, 86.8%, 93.4%, 95.6%, respectively. The sensitivity, negative predictive value (NPV), and accuracy of FPFL were higher in Group H than in Group D (p = 0.041, 0.034, 0.005). All three segmentation sensitivity groups showed higher specificity, positive predictive value, NPV, and accuracy of FPFL, as compared to DSA. CONCLUSION FlightPlan for Liver is a valuable tool for increasing detection of HCC tumor feeding vessels, as compared to standard DSA analysis, particularly in small HCC. Manual adjustment of segmentation sensitivity improves the accuracy of FPFL.

A 62-year-old man was admitted, and thoracic endovascular aortic repair (TEVAR) procedure was performed to treat an accidentally detected aortic aneurysm, which was 63 mm in diameter. While performing TEVAR, the passage of the stentgraft introducer system was impossible due to the prolapse of the introducer system into a wide-necked aneurysm; this aneurysm was located at the greater curvature of the proximal descending thoracic aorta. In order to advance the introducer system, a compliant balloon was inflated. Thus, we created an artificial wall in the aneurysm with this inflated balloon. Finally, we were able to advance the introducer system into the target zone. Index terms: Thoracic aortic aneurysm; Thoracic endovascular aortic repair; Wide-necked aneurysm; Proximal descending thoracic aorta; Aortic arch; Balloon-supported passage of an introducer system

Background Concurrent chemoradiation therapy (CCRT) followed by hepatic arterial infusional chemotherapy (HAIC) was reported to be effective for advanced hepatocellular carcinoma (HCC) with portal vein thrombosis. However, transarterial chemoembolization (TACE) is not preferred in this setting. The aim of this study was to assess the factors affecting survival after CCRT, including additional TACE during repeated HAIC. Methods Thirty-eight patients who underwent CCRT as the initial treatment for Barcelona Clinic Liver Cancer stage C HCC with vascular invasion between 2009 and 2016 were reviewed retrospectively. During CCRT, 5-fluorouracil (5-FU) was infused via chemoport during the first and last five days of five weeks of external beam radiation therapy. After CCRT, repeated HAIC with cisplatin and 5-FU was performed monthly. Nineteen patients (50%) underwent additional TACE between repeated HAICs. Factors related to overall survival and progression free survival (PFS) were analyzed. Results The mean age of patients was 55 years (male:female, 33:5). Underlying liver diseases were hepatitis B, hepatitis C and non-B/C in 29, 1 and 8 patients, respectively. The median radiation dose was 4500 cGy. The objective response (OR) rate at one months after CCRT was 36.8%. The median PFS was 7.4 (range, 1.8 − 32.1) months. The median overall survival was 11.6 (range 2.8-65.7) months. Achieving an OR after CCRT (hazard ratio [HR], 0.028; P

Objective This study aimed to assess the technical feasibility, procedural safety, and long-term therapeutic efficacy of a small-sized ambulatory thoracic vent (TV) device for the treatment of pneumothorax. Materials and methods From November 2012 to July 2013, 18 consecutive patients (3 females, 15 males) aged 16-64 years (mean: 34.7 ± 14.9 years, median: 29 years) were enrolled prospectively. Of these, 15 patients had spontaneous pneumothorax and 3 had iatrogenic pneumothorax. A Tru-Close TV with a small-bore (11- or 13-Fr) catheter was inserted under bi-plane fluoroscopic assistance. Results Technical success was achieved in all patients. Complete lung re-expansion was achieved at 24 hours in 88.9% of patients (16/18 patients). All patients tolerated the procedure and no major complications occurred. The patients' mean numeric pain intensity score was 2.4 (range: 0-5) in daily life activity during the TV treatment. All patients with spontaneous pneumothorax underwent outpatient follow-up. The mean time to TV removal was 4.7 (3-13) days. Early surgical conversion rate of 16.7% (3/18 patients) occurred in 2 patients with incomplete lung expansion and 1 patient with immediate pneumothorax recurrence post-TV removal; and late surgical conversion occurred in 2 of 18 patients (11.1%). The recurrence-free long-term success rate was 72.2% (13/18 patients) during a 3-year follow-up period from November 2012 to June 2016. Conclusion TV application was a simple, safe, and technically feasible procedure in an outpatient clinic, with an acceptable long-term recurrence-free rate. Thus, TV could be useful for the immediate treatment of pneumothorax.

Objective To assess the feasibility of computed tomography (CT) lymphography using ethiodized oil for sentinel node mapping in experimentally induced VX2 carcinoma in the rabbit thigh. Materials and methods This experiment received approval from the institutional animal use and care administrative advisory committee. Twenty-three rabbits with VX2 carcinoma in the thigh underwent CT before and after (1 hour, 2 hour) peritumoral injection of 2 mL ethiodized oil. After the CT examination, sentinel nodes were identified by peritumoral injection of methylene blue and subsequently removed. The retrieved sentinel and non-sentinel lymph nodes were investigated with radiographic and pathologic examinations. Based on the comparison of CT findings with those of radiographic and pathologic examinations, the diagnostic performance of CT for sentinel node identification was assessed. Results All 23 rabbits showed 53 ethiodized oil retention nodes on post-injection CT and specimen radiography, and 52 methylene blue-stained nodes at the right femoroiliac area. Of the 52 blue-stained sentinel nodes, 50 nodes demonstrated ethiodized oil retention. Thus, the sentinel node detection rate of CT was 96% (50 of 52). On pathologic examination, 28 sentinel nodes in 17 rabbits (nodes/rabbit, mean ± standard deviation, 1.7 ± 0.6) harbored metastasis. Twenty seven of the 28 metastatic sentinel nodes were found to have ethiodized oil retention. Conclusion Computed tomography lymphography using ethiodized oil may be feasible for sentinel node mapping in experimentally induced VX2 carcinoma in the rabbit thigh.

The purpose of this study was to clarify the frequency of and risk factors for liver abscess formation after transarterial chemoembolization (TACE) in patients with hepatocellular carcinoma or metastatic hepatic tumors after undergoing bilioenteric anastomosis.From January 1996 to June 2012, 25 patients (21 men, four women; age range, 34-74 years) with hepatocellular carcinoma (n = 12) or metastatic hepatic tumors (n = 13) with an underlying bilioenteric anastomosis underwent 65 TACE procedures. The incidence of liver abscess, predisposing factors (diabetes, Child-Pugh class, leukopenia, tumor number, tumor size, tumor burden, tumor type, portal vein thrombus, lipiodol dose, particulate embolization, embolization selectivity, oily portogram, antibiotic prophylaxis, and occurrence of liver abscess at initial TACE), and clinical outcome were evaluated. Statistical analysis for relations between liver abscess and predisposing factors was performed by Fisher exact test and linear-by-linear association.Liver abscess developed after 17 of 65 (26.2%) TACE procedures performed on 12 of 25 (48%) patients. Two patients died of progression of liver abscess into sepsis. Univariate and multivariate analyses showed that leukopenia (p = 0.029), occurrence of liver abscess at initial TACE (p = 0.082), and particulate embolization or oily portogram (grade 2) (p = 0.001) were associated with a higher incidence of liver abscess.The incidence of liver abscess was high among patients with bilioenteric anastomoses who underwent TACE. Leukopenia, occurrence of liver abscess at initial session of TACE, and particulate embolization or oily portogram (grade 2) were associated with the development of liver abscess.

This study was designed to evaluate the safety of chemotherapeutic infusion or chemoembolization by way of the cystic artery in patients with hepatocellular carcinoma (HCC) supplied exclusively by the cystic artery.Between Jan 2002 and Dec 2011, we performed chemotherapeutic infusion or chemoembolization using iodized oil for the treatment of 27 patients with HCC supplied exclusively by the cystic artery. Computed tomography (CT) scans, digital subtraction angiograms, and medical records were retrospectively reviewed by consensus.The cystic artery originated from the main right hepatic artery in 24 (89 %) patients, from the right anterior hepatic artery in 2 (7 %) patients, and from the left hepatic artery in 1 (4 %) patient. Selective catheterization of the cystic artery was achieved in all patients. Superselection of tumor-feeding vessels from the cystic artery was achieved in 7 patients (26 %). Chemotherapeutic infusion was performed in 18 patients (67 %), and chemoembolization was performed in 9 patients (33 %). There were no major complications and only 2 minor complications, including vasovagal syncope and nausea with vomiting. Individual tumor response supplied exclusively by the cystic artery at the follow-up enhanced CT scan were complete response (n = 16), partial response (n = 3), and stable disease (n = 8).HCC supplied exclusively by the cystic artery can be safely treated without severe complications by chemotherapeutic infusion or chemoembolization using iodized oil through the cystic artery.

The present work describes the preliminary results of a new method of minimally invasive thrombectomy in the treatment of thrombosed arteriovenous fistula (AVF) with dilated aneurysm. Data from 25 patients who were treated with this minimal venotomy technique were retrospectively reviewed. The minimal venotomy was made on the dilated fistula, and thrombectomy was performed with forceps and Fogarty catheters through the venotomy site. Technical and clinical success was achieved in all 25 patients. There were two major and two minor complications (8% each). The two major complications consisted of bleeding at the venotomy site after early suture removal.

The objective of our study was to compare the diagnostic performances of two commercial computer-aided detection (CAD) systems and a CAD system developed in our laboratory, which we refer to as an "academic CAD system," for polyp detection on CT colonography (CTC) and to assess the detection characteristics of the CAD systems.One hundred three polyps (48 polyps6 mm and 55 polypsor = 6 mm; 45 sessile, 33 flat, and 25 pedunculated polyps) were created. Each CTC data set was analyzed using two commercial CAD systems (Computer Assisted Reader [CAR] and Polyp Enhanced View [PEV]) and one Hessian matrix-based academic CAD system. Per-polyp sensitivities according to polyp size and shape were compared among the three CAD systems. The average number and causes of false-positives (FPs) were analyzed and compared.Per-polyp sensitivity for all polyps was significantly better for the academic CAD system (83.5%) than for both commercial CAD systems (64.1%) (p0.01). However, the difference in per-polyp sensitivity for polypsor = 6 mm was not significant (p0.017). According to morphology, per-polyp sensitivities as determined with the CAR, PEV, and academic CAD systems for flat, sessile, and pedunculated polyps were 51.5%, 57.6%, and 81.8%; 60.0%, 62.2%, and 84.4%; 88.0%, 76.0%, and 84.0%, respectively. The average number of FPs was not significantly different (p0.05); however, the distribution of the causes of FPs for the three systems was significantly different (p0.001).For polypsor = 6 mm, the three CAD systems showed comparable per-polyp sensitivities. Although the number of FPs was not significantly different, the distribution of the causes of FPs for each of the CAD systems was significantly different.

To determine the frequency of normal appendix visualization at low-dose (LD) unenhanced computed tomography (CT) performed with a 16- or 64-detector row scanner when images are reviewed by using the sliding slab averaging technique.The institutional review board approved the study and waived the informed consent requirement. A total of 259 patients, 37 (14.3%) of whom had previously undergone appendectomy, underwent LD unenhanced CT (mean effective dose, 1.7 mSv) performed with a 16- or 64-detector row scanner to assess urinary colic. Three readers used the sliding slab averaging technique to retrospectively review the thin-section (0.67- or 2.00-mm section thickness) images and grade the appendix as absent, unsurely or partly visualized, or clearly and entirely visualized. Interobserver agreement was measured with weighted kappa statistics. McNemar tests were used to compare sensitivity between the readers. Logistic regression analysis was performed to assess the effects of body mass index, patient sex, and type of CT scanner on appendiceal visualization.The kappa statistics for each reader pair were as follows: 0.97 for agreement between readers 1 and 2, 0.93 for agreement between readers 2 and 3, and 0.92 for agreement between readers 1 and 3. Each reader clearly identified the entire appendix in 213 (96.0%), 209 (94.1%), and 205 (92.3%) of the 222 patients without a history of appendectomy. When unsurely or partly visualized appendices were included, the frequencies increased to 99.1% (n = 220), 98.7% (n = 219), and 97.3% (n = 216), respectively, for readers 1, 2, and 3. These frequencies rarely differed between the readers. (P values ranged from .021 to greater than .99.) The three readers consistently reported that the appendix was not visualized in the 37 patients who had undergone appendectomy. None of the tested variables significantly affected appendix visualization.Most normal appendices are visualized on thin-section LD unenhanced CT images reviewed with the sliding slab averaging technique.

Transarterial chemoembolization (TACE) is a widely accepted nonsurgical modality used for the treatment of multinodular hepatocellular carcinoma (HCC). The careful selection of the candidate is important due to the risk of developing various side effects. Fever, nausea, abdominal pain, and liver enzyme elevation are commonly known side effects of TACE. Hepatic failure, ischemic cholecystitis, and cerebral embolism are also reported, although their incidence might be low. Pulmonary complication after TACE is rare, and the reported cases of lipiodol pneumonitis are even rarer. A 53-year-old man was treated with TACE for rup- tured HCC associated with hepatitis B virus infection. On day 19 after the procedure, the patient complained of dyspnea and dry cough. Chest computed tomography showed diffuse ground glass opacities in the whole- lung fields, suggesting lipiodol-induced pneumonitis. After 2 weeks of conservative management, the clinical symptoms and radiologic abnormalities improved. Reported herein is the aforementioned case of lipiodol-in- duced pnemonitis after TACE, with literature review.

Purpose: To evaluate the long term patency of transjugular intrahepatic portosystemic shunts (TIPS) and to compare the patency rate of covered and uncovered stents in TIPS. Materials and Methods: The study population included 78 patients with portal hypertension that underwent TIPS between January 1999 and July 2007 at our institution using uncovered stents in 53 patients and covered stents in 25 patients. The primary and secondary patency rates of TIPS were estimated to compare the uncovered and covered stent groups. Results: The primary and secondary patency rates of the TIPS patients were found to be 83.9% and 93.9% at the 6 month follow-up and 73.5% and 88.5% at the12 month follow-up for uncovered and covered stents, respectively. A breakdown patency rates for the 12 month follow-up revealed that the primary patency rates were 76.6% and 66.3% for uncovered and covered stents, respectively; whereas, the secondary patency rates were 94.3% and 73.8% for the uncovered and covered stents, respectively. A comparative analysis did not provide evidence to suggest that a difference exists between the patency rates of the uncovered and covered stent groups (p>0.05). Conclusion: No significant difference was found between the patency rates of the uncovered and covered stent groups. A follow-up to this study would be a more thorough randomized evaluation of the different types of covered stents to compare long-term patency rates.