Safety and efficacy of side-by-side versus stent-in-stent stenting for malignant hilar biliary obstruction: a systematic review and meta-analysis.

Objectives: Stenting of the malignant hilar biliary obstruction (MHBO) area for bile drainage is challenging. Bilateral stenting techniques of stent-in-stent (SIS) and stent-by-stent (SBS) have shown promising results. This study evaluates the efficacy of different stenting methods for MHBO. Design: A meta-analysis was performed to determine the efficacy of SIS and SBS stenting strategies for MHBO. Data sources and methods: Medical databases such as PubMed, Web of Science, Embase, and Scopus, were searched up to August 2023. We selected eligible studies reporting the data on technical and clinical success, adverse events, and incidence of re-obstruction (RO) of SBS and SIS groups in MHBO patients. We compared the outcomes of SBS and SIS groups. Results: A total of 9 studies comparing the data of 545 patients (268 in the SBS group and 277 in the SIS stenting group) were analyzed. There was no significant difference (p > 0.05) in the odds ratio (OR) of Re-obstruction (RO) 0.87 (95% confidence interval (95% CI) 0.6-1.25), technical success 0.58 (95% CI 0.16-2.11), clinical success 1.13 (95% CI 0.62-2.07), and adverse events 1.53 (95% CI 0.88-2.64). The mean difference in procedure time was -12.25 min (95% CI -18.39, -6.12), and the hazard ratio of stent patency was 1.22 (95% CI 1.01-1.47), favoring SBS, with high heterogeneity (I 2 = 94%). There was no significant difference in HR for survival 1.05 (95% CI 0.95-1.16) with high heterogeneity (I 2 = 84%). Conclusion: Compared with SIS, SBS showed better stent patency with comparable technical and clinical success and adverse events. Prospero registration: The registration number for this study on PROSPERO is CRD42024523230.

Trisectoral Metal Stenting Using Combined Stent-by-Stent and Stent-in-Stent Method for Malignant Hilar Biliary Obstruction: A Prospective Pilot Study.

BACKGROUND: Endoscopic trisectoral metal stent (MS) placement for malignant hilar biliary obstruction (MHBO) poses technical challenges, although it may prolong survival and stent patency. Combined stent-by-stent and stent-in-stent (SBSIS) methods can reduce technical difficulty. This study aimed to examine the use of the SBSIS in patients with Bismuth type III or IV MHBO. METHODS: This prospective pilot study enrolled 30 eligible patients between January 2020 and October 2022. The study outcomes included technical and clinical success, recurrent biliary obstruction (RBO), and adverse events (AE) besides RBO associated with SBSIS for MHBO. RESULTS: The technical success rate was 93.3% (28/30 patients). Clinical success was achieved in all patients with technical success. The early and late AEs rates were 6.7% (2/30) and 7.1% (2/28), respectively. The incidence of RBO was 35.7% (10/28). RBO was treated with an endoscopic transpapillary approach in eight patients and an endoscopic ultrasound-guided transmural approach in two patients. The median time to RBO was 162 days, and the median overall survival was 148 days. CONCLUSIONS: This first prospective study investigating the SBSIS method demonstrated good technical feasibility with a low AE rate. Therefore, it can be considered a better option when contemplating trisectoral MS placement for high-grade MHBO.

A case of tracheal stenosis due to anaplastic thyroid carcinoma treated using the stent-in-stent method.

Tracheal AERO stent collapse is a rare complication compared to bronchial AERO stent collapse due to differences in the nitinol framework thickness. A 58-year-old man with a bulky anaplastic thyroid carcinoma was referred to our hospital due to exacerbation of tracheal stenosis despite the administration of lenvatinib. His tracheal stenosis exhibited a severe extrinsic compression pattern with a length of 8 cm. Because tracheotomy was inappropriate, we placed an 18 × 80 mm AERO stent. Five months later, he was readmitted with severe dyspnea due to collapse of the distal portion of the stent caused by tumor growth. Because stent removal was difficult, we placed an additional AERO stent (18 × 60 mm) to cover the collapsed portion. The additional stent successfully expanded the collapse and improved his dyspnea. To our knowledge, this is the first case where a tracheal AERO stent collapse due to a poor prognosis tumor was treated with the stent-in-stent method.

The evaluation of bilateral stenting using braided or laser-cut self-expandable metallic stent for malignant hilar biliary obstruction.

OBJECTIVES: Bilateral self-expandable metallic stent (SEMS) placement for unresectable malignant hilar biliary obstruction (UMHBO) is an effective option for biliary drainage with long-term stent patency. Laser-cut and braided SEMS can be used for bilateral SEMS placement. This study aimed to clarify any differences in the clinical features and proper use of the laser-cut and braided SEMS placement using the stent-in-stent method for UMHBO. METHODS: In this study, 78 patients who underwent bilateral stent-in-stent SEMS placement for UMHBO were included. The patients were divided into the laser-cut (n = 33) and braided groups (n = 45). Both groups were compared for technical and clinical success, adverse events (AEs), time to recurrent biliary obstruction (TRBO), overall survival, and endoscopic reintervention (ERI). RESULTS: There were no significant differences in technical and clinical success rates (laser-cut vs. braided group, 97% vs. 95.6%, P = 1.0), AEs (21.2% vs. 15.6%. P = 0.56), median TRBO (242 days vs. 140 days, P = 0.36), and median overall survival (654 days vs. 675 days, P = 0.58). ERI was required in 15 patients in the laser-cut group and in 20 patients in the braided group. The technical and clinical success rates of ERI (60% vs. 85%) were not significantly different (P = 0.13); however, the median ERI procedure time was significantly longer in the laser-cut group (38 min) than in the braided group (22 min; P = 0.02). CONCLUSION: No significant difference in initial SEMS placement was noted between the laser-cut and braided groups; however, the laser-cut group required a longer ERI procedure time than that required by the braided group. The use of braided SEMS may be a convenient option for ERI.

Endoscopic Transpapillary Stenting for Malignant Hilar Biliary Stricture: Side-by-Side Placement versus Partial Stent-in-Stent Placement.

BACKGROUND/AIMS: Endoscopic uncovered metal stent (UMS) placement has been widely performed for unresectable hilar malignant biliary stricture (UHMBS). Two stenting methods are used for the two bile duct branches: side-by-side placement (SBS) and partial stent-in-stent placement (PSIS). However, it remains controversial whether SBS or PSIS is superior. This study aimed to compare SBS and PSIS in UHMBS cases with UMS placement in two branches of the IHD. METHODS: This retrospective study included 89 cases of UHMBS treated with UMS placement through the SBS or PSIS technique using endoscopic retrograde cholangiopancreatography at our institution. Patients were divided into two groups, SBS (n = 64) and PSIS (n = 25), and compared. RESULTS: Clinical success was achieved in 79.7% and 80.0% in the SBS and PSIS groups, respectively (p = 0.97). The adverse event rate was 20.3% and 12.0% in the SBS and PSIS groups, respectively (p = 0.36). The recurrent biliary obstruction (RBO) rate was 32.8% and 28.0% in the SBS and PSIS groups, respectively (p = 0.66). The median cumulative time to RBO was 224 and 178 days in the SBS and PSIS groups, respectively (p = 0.52). The median procedure time was 43 and 62 min in the SBS and PSIS groups, respectively, which was significantly longer in the PSIS group (p = 0.014). CONCLUSIONS: No significant differences were noted in the clinical success rate, adverse event rate, time to RBO, or overall survival between the SBS and PSIS groups, other than the significantly longer procedure time in the PSIS group.

Percutaneous insertion of a novel dedicated metal stent to treat malignant hilar biliary obstruction.

BACKGROUND: Percutaneous bilateral biliary stenting is an established method for the management of unresectable malignant hilar biliary obstruction. AIM: To evaluate the efficacy and safety of a novel uncovered biliary stent, specifically designed for hilar reconstruction. METHODS: This, single-center, retrospective study included 18 patients (mean age 71 ± 11 years; 61.1% male) undergoing percutaneous transhepatic Moving cell stent (MCS) placement for hilar reconstruction using the stent-in-stent technique for malignant biliary strictures, between November 2020 and July 2021. The Patients were diagnosed with cholangiocarcinoma (12/18; 66.6%), gallbladder cancer (5/18; 27.7%), and colorectal liver metastasis (1/18; 5.5%). Primary endpoints were technical (appropriate stent placement) and clinical (relief from jaundice) success. Secondary endpoints included stent patency, overall survival, complication rates and stent-related complications. RESULTS: The technical and clinical success rates were 100% (18/18 cases). According to Kaplan-Meier analysis, the estimated overall patient survival was 80.5% and 60.4% at 6 and 12 mo respectively, while stent patency was 90.9% and 68.2% at 6 mo and 12 mo respectively. The mean stent patency was 172.53 ± 56.20 d and median stent patency was 165 d (range 83-315). Laboratory tests for cholestasis significantly improved after procedure: mean total bilirubin decreased from 15.2 ± 6.0 mg/dL to 1.3 ± 0.4 mg/dL (P < 0.001); mean γGT decreased from 1389 ± 832 U/L to 114.6 ± 53.5 U/L (P < 0.001). One periprocedural complication was reported. Stent-related complications were observed in 5 patients (27.7%), including 1 occlusion (5.5%) and 1 stent migration (5.5 %). CONCLUSION: Percutaneous hilar bifurcation biliary stenting with the MCS resulted in excellent clinical and technical success rates, with acceptable complication rates. Further studies are needed to confirm these initial positive results.

Stent-in-stent technique under fluoroscopy for removal of embedded esophageal stent: a retrospective case series.

Background: Treatment of complications after esophageal stent placement and methods for removal of stents need to be improved. The purpose of this study was to evaluate the safety and efficacy of stent-in-stent (SIS) removal of esophageal stent under fluoroscopy. Methods: This study analyzed the clinical data of consecutive patients undergoing esophageal stent removal by the SIS technique under fluoroscopy. The procedure was performed under local anesthesia on conscious sedated patients. Under fluoroscopy, a second esophageal stent was released within the lumen of the first esophageal stent. The second stent was larger than the first, with both ends protruding 1-2 cm beyond the ends of the first stent. Four weeks later, both esophageal stents were removed by the SIS technique under fluoroscopy. All procedures were performed by the same interventional radiologist (with >10 years of experience). Results: A total of 25 patients were treated by the SIS removal technique. In 23 patients, the first esophageal stent was easily removed by the SIS technique; in the other 2 patients, stent fracture occurred, and some residual nitinol wire had to be removed endoscopically. No serious complications occurred in any patient. Conclusions: The SIS removal technique appears to be a safe and effective method for removal of embedded esophageal metallic stents.

Hemifacial spasm due to vertebral artery dissecting aneurysm treated with stent-in-stent placement; Pre- and post-treatment evaluation by 3D multifusion imaging using silent MR angiography.

Background: Hemifacial spasm (HFS) due to vertebral artery (VA) dissecting aneurysm (VADA) is rare and endovascular treatment has been performed in selected cases. Case Description: We encountered a case of HFS caused by VADA that was managed with endovascular stent placement and additional stent-in-stent placement. Therapeutic strategies and benefits based on pre- and post-treatment evaluation by 3D multifusion imaging using silent MRA were discussed. Conclusion: This is the first case report of stent-in-stent placement in successful treatment of HFS caused by VADA, in which relief of neurovascular contact was demonstrated by multifusion imaging.

Side-by-side versus stent-in-stent bilateral stenting for malignant hilar biliary obstruction: a meta-analysis.

Introduction: Both side-by-side (SBS) and stent-in-stent (SIS) bilateral stenting have been used for patients with malignant hilar biliary obstruction (MHBO). However, it is unclear which technique is better. Aim: This meta-analysis is conducted to investigate the clinical efficacy and safety of SBS and SIS bilateral stenting for patients with MHBO. Material and methods: Relevant studies were searched in PubMed, Embase, Cochrane Library, Wanfang, VIP, and CINK databases. The timeline for the searches was from the establishment of the database to September 2021. The relative outcomes are pooled. Results: A total of 7 studies fulfilled the inclusion criteria and entered into this meta-analysis. The pooled technical success rate was significant higher in the SIS group than that in the SBS group (p = 0.04). The pooled early complication rate was significantly lower in the SIS group than in the SBS group (p = 0.04). The pooled stent re-obstruction rate was significantly lower in the SBS group than in the SIS group (p = 0.04). The pooled stent patency duration was significantly longer in the SBS group than in the SIS group (p = 0.01). The pooled functional success rates (p = 0.79), total complication rates (p = 0.34), and overall survival duration (p = 0.27) were comparable between 2 groups. Egger test did not show any publication bias. Conclusions: When comparing the SBS and SIS bilateral stenting for patients with MHBO, although SIS technique may have the superiorities of technical success and early complication rates, the longer stent patency was achieved by the SBS technique.

Recent advances regarding endoscopic biliary drainage for unresectable malignant hilar biliary obstruction.

Biliary drainage for unresectable malignant hilar biliary obstruction (UMHBO) is still associated with a number of controversies to be resolved. The superiority of bilateral drainage in comparison to unilateral drainage has not been proven obviously yet. However, bilateral drainage is necessary to treat obstructive jaundice in some UMHBO patients, and this may be connected with preservation of the functional liver volume. The partial stent-in-stent (SIS) method and side-by-side (SBS) method developed as bilateral drainage methods. There is no significant difference in the technical or clinical success rates of the SIS and SBS methods. In addition, these methods are comparable in terms of adverse events, patency period, and survival period. On the other hand, reintervention for recurrent biliary obstruction (RBO) after the SBS method seems to be easier in comparison to cases with RBO after the SIS method; however, there is no remarkable difference in the clinical results of these procedures. Endoscopic ultrasound (EUS)-guided biliary drainage also has become an option for patients with UMHBO. Left hepatic drainage using EUS-guided hepaticogastrostomy (EUS-HGS) has become common; however, few studies have reported the results of bridging drainage for the right lobe using the EUS-HGS route or EUS-guided hepaticojejunostomy. A few studies addressed the results of newly designed stents, such as the 6-mm braided metal stent and inside stent. The development of various drainage methods and new devices is necessary for the further advancement of endoscopic biliary drainage for patients with UMHBO, further studies to evaluate those methods and devices are warranted.

Endoscopic re-intervention after stent-in-stent versus side-by-side bilateral self-expandable metallic stent deployment.

BACKGROUND AND AIM: Endoscopic bilateral self-expandable metallic stent (SEMS) placement for unresectable malignant hilar biliary obstruction (MHBO) is widely performed; however, re-intervention after recurrent biliary obstruction (RBO) is often challenging. We compared stent-in-stent (SIS) and side-by-side (SBS) SEMS placement for MHBO considering re-intervention for RBO. METHODS: One hundred five consecutive patients with MHBO who underwent endoscopic bilateral SEMS placement in our hospital and its affiliated institutions were enrolled in this study; 75 patients underwent partial SIS deployment between December 2005 and December 2012; and 30 underwent SBS deployment between January 2013 and March 2019. Initial treatments and re-interventions in each group were retrospectively evaluated. RESULTS: Technical success rate (92% vs 100%, P = 0.179), procedure duration (46 vs 35 min, P = 0.382), functional success rate (97.1% vs 100%, P = 1.00), complication rate (24.6% vs 20.0%, P = 0.797), time to RBO (260 vs 312 days; Gray test, P = 0.815), and rate of RBO (59.4% vs 70.0%, P = 0.371) were not significantly different between the SIS and SBS groups. However, bilateral re-stenting with plastic stents through SEMS was successful in 63.4% of patients in the SIS group compared with 100% of patients in the SBS group (P = 0.0013). Median time to RBO upon first re-stenting with a plastic stent was 75 days (range, 11-195 days). CONCLUSIONS: Endoscopic re-stenting after RBO was significantly more successful in the SBS group than in the SIS group. SBS method is suitable for MHBO considering revisionary stent placement.

Bilateral stenting for hilar biliary obstruction: a meta-analysis of side-by-side versus stent-in-stent.

PURPOSE: To evaluate the efficacy of stent-in-stent (SIS) and side-by-side (SBS) bilateral stenting for treating malignant hilar biliary obstruction (MHBO). MATERIAL AND METHODS: Relevant studies in Pubmed, Embase, and Cochrane Library were identified through June 2020. This meta-analysis was conducted using RevMan v5.3, using relevant endpoint data relating to clinical and technical success, complications, stent dysfunction, and overall survival (OS) rates extracted from these studies. RESULTS: We identified six relevant studies which included 315 MHBO patients treated with either SBS (n = 161) or SIS bilateral (n = 154) stenting. We saw no significant difference between these two groups with respect to clinical success (OR: 1.07; 95% CI: 0.46, 2.49, p = .87), complication (HR: 0.12; 95% CI: -0.04, 0.27, p = .15), stent dysfunction (OR: 0.68; 95% CI: 0.42, 1.10, p = .11), or OS (HR: 0.97; 95% CI: 0.82, 1.16, p = .74). However, the SBS group exhibited significantly lower technical success rates (OR: 6.55; 95% CI: 1.10, 38.83, p = .04). Significant heterogeneity was only detected for the endpoint of complication rates (I2 = 60%). CONCLUSION: These results suggest that SIS bilateral stenting yields better rates of technical success than does SBS bilateral stenting in MHBO patients.

A Case of Intraprocedural Plaque Protrusion during Carotid Artery Stenting Using the Stent-in-Stent Technique for Carotid Artery Stenosis with Unstable Plaque.

Objective: Carotid artery stenting (CAS) using the stent-in-stent technique was reported to prevent intraprocedural plaque protrusion (PP) in patients with carotid artery stenosis with unstable plaque. We report a case of intraoperative PP after CAS despite the use of stent-in-stent technique. Case Presentation: A 63-year-old man presented with rapid progression of right carotid artery stenosis with unstable plaque during follow-up and was admitted to undergo CAS. Under local anesthesia with Mo.Ma Ultra and FilterWire EZ protection, CAS was performed using the stent-in-stent technique. The first 8 mm × 29 mm Carotid Wallstent (CWS) was placed. The second CWS (6 mm × 22 mm) was placed in a stent-in-stent manner to match the stenotic lesion, and conservative postdilation was performed. Then the third CWS (6 mm × 22 mm) was added due to the presence of PP on intravascular ultrasonography (IVUS). No postoperative neurological abnormalities were found, and no new high-signal areas were observed on diffusion-weighted MRI the day after surgery. The patient was discharged without postoperative complications. No stroke and restenosis were observed at 3 months after CAS. Conclusion: PP can occur even with stent-in-stent technique, suggesting the importance of diagnosis by IVUS.

Prospective multicenter evaluation of moving cell metallic stents in endoscopic multiple stent deployment for hepatic hilar obstruction.

BACKGROUND AND AIM: Bilateral stent deployment for malignant biliary obstruction (MHBO) can be achieved using side-by-side (SBS) or stent-in-stent (SIS) procedures. Compared with SBS techniques, the procedural steps of SIS are technically complex due to the necessity of introducing the delivery system into a contralateral biliary tract through the mesh of the SEMS. To overcome this issue, a novel uncovered SEMS, the HILZO Moving Cell Stent (MCS) has been released. The present study examined the technical feasibility of treating MHBO using bilateral deployment of this novel stent without dilating the mesh of the first stent to achieve insertion of the second stent within a single session, using a prospective, multicenter setting. METHOD: The primary outcome in the present study was the technical success rate. Technical success was defined as deployment of bilateral MCSs into two or more biliary tracts using SIS without a dilation device in a single-session. RESULTS: A total of 27 patients with complications of MHBO were enrolled in this study. Bilateral SIS using two MCS was successfully performed in 23 patients without using dilation devices among 27 patients (initial technical success rate; 85.2%). Median time to recurrent biliary obstruction (TRBO) was 271 days. Stent dysfunction was observed in 12 patients (44.4%), and re-intervention was successfully performed in all patients without one patient who instead received best supportive care. CONCLUSIONS: The SIS technique using MCS without dilation of the mesh may be technically feasible and safe. In addition, this may be useful for re-intervention. Further comparative randomized trials are needed.

Endoscopic Bilateral Stent-in-Stent Versus Stent-by-Stent Deployment in Advanced Malignant Hilar Obstruction: A Meta-Analysis and Systematic Review.

BACKGROUND AND AIM: There is no clear data to compare the effectiveness and safety of bilateral stent-in-stent (SIS) or stent-by-stent (SBS) deployment for advanced malignant hilar obstruction (MHO). This meta-analysis was done to investigate clinical outcomes of these deployment methods. METHODS: We did a literature search to identify studies that reported the clinical outcomes of bilateral metal stents in patients with advanced MHO. Weighed pooled rates (WPR) along with 95% confidence interval (95% CI) were calculated in order to compare outcomes including technical and clinical success, adverse events, and stent occlusion between the two groups. We conducted a meta-analysis using a random-effects model. RESULTS: Five comparative studies with 250 patients, and 20 single-arm studies for the SIS or SBS method were eligible for the meta-analysis and systematic review. The bilateral SIS deployment had a significantly higher technical success rate than did SBS deployment (OR 6.43; 95% CI 1.08-38.09). There was no difference in the clinical success (OR 1.23; 95% CI 0.45-3.38), overall adverse events rates (OR 0.42; 95% CI 0.15-1.18), or overall occlusion rate (OR 1.55; 95% CI 0.89-2.70). As a single-armed group, WPR of technical success of the SIS and SBS groups was 96.4% and 89.6%, respectively. Clinical success was 97.5% and 98.3%. Overall, adverse events were 35.9% and 22.6%. Occlusion rates were 27.7% and 37.7%. CONCLUSIONS: Although there was a lack of quality data and heterogeneity, bilateral SIS deployment had a higher technical feasibility than did the SBS method in patients with advanced MHO, without differences in terms of clinical success, adverse events, or occlusion rates.

Stent-in-stent technique for the management of blood blister-like basilar apex aneurysms.

Blood blister-like basilar apex aneurysms are rare thin-walled vascular lesions with a poorly defined aneurysmal neck. We present two patients with ruptured blister aneurysms of the basilar apex who were treated using the stent-in-stent technique. Long-term follow-up showed persistent and complete occlusion of the aneurysms without radiographically or neurological complications. There is no optimal treatment of choice for the basilar apex blood blister-like aneurysms. Double- or triple-stent placement using the stent-in-stent technique can be a safe and feasible option for these uncommon and challenging intracranial aneurysms.

Comparison between stenting and conservative management of posterior circulation perforator aneurysms: Systematic review and case series.

PURPOSE: Posterior circulation perforator aneurysms (PCPAs) are a rare type of intracranial aneurysms whose natural history and optimal clinical management are still largely unexplored. This study aims to report our experience with treating ruptured PCPAs and to provide a systematic review of the literature to compare the two most established treatment options, endovascular stenting, and conservative management including administration of antifibrinolytic drugs and watchful waiting. METHODS: We performed a systematic review of the literature following the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Major databases were searched for case reports and case report series written in the English language between 1995 and 2020. Additionally, we retrospectively reviewed our stroke center database for cases of ruptured PCPAs between January 2014 and July 2020. Endovascular stenting and conservative treatment were compared using endpoints, including favorable outcome rate (mRS 0-2), occlusion rate, mortality rate, periinterventional complication rate, and re-hemorrhage rate. RESULTS: We identified 31 patients treated endovascularly using stents and 33 patients treated conservatively, with the administration of antifibrinolytic drugs in 3 of them. Our analysis showed no statistically significant difference between the groups, except for the occlusion rate. CONCLUSIONS: The optimal management strategy of PCPAs is still unknown, but stenting can be considered as an effective occlusion method with an acceptable complication rate. Preventive ventricular drainage may be necessary due to the high hydrocephalus rate encountered in ruptured PCPAs.

Percutaneous stent-in-stent placement with large cell-type stents for malignant hilar biliary obstruction.

BACKGROUND: To overcome the technical difficulty of bilateral stent-in-stent placement, large cell-type biliary stents have been developed. However, most of the studies using large cell-type stents were conducted with endoscopic method. PURPOSE: To evaluate the efficacy and safety of percutaneous stent placement with a stent-in-stent method using large cell-type stents in patients with malignant hilar biliary obstruction. MATERIAL AND METHODS: From December 2015 and October 2018, 51 patients with malignant hilar biliary obstruction were retrospectively studied. All of the patients underwent bilateral (n=46) or unilateral (n=5) stenting in a T, Y, or X configuration with a stent-in-stent method using large cell-type stents. Technical success, complications, successful internal drainage, stent patency, and patient survival were analyzed. RESULTS: A total of 118 stents were successfully placed in 51 patients (100.0%). Three patients had minor complications with self-limiting hemobilia. Major complications were not observed in any patient. Successful internal drainage was achieved in 45 patients (88.2%). Clinical follow-up information until death or the end of the study was available for 50 of 51 patients. The median patient survival was 285.5 days (95% confidence interval [CI] 197-374). Stent dysfunction occurred in 16 patients (35.6%) due to tumor ingrowth (n=9) or tumor ingrowth combined with biliary sludge (n=7) among the patients who achieved successful internal drainage. Median stent patency was 179 days (95% CI 104-271). CONCLUSION: Percutaneous stent-in-stent placement with large cell-type stents is technically feasible and safe, and can be an effective technique in patients with malignant hilar biliary obstruction.

Ineffective endovascular treatment of a giant internal carotid artery aneurysm.

PURPOSE: Despite a growing range of therapeutic possibilities, including various intravascular methods, treating cerebral aneurysms can be still a therapeutic challenge. A growing number of patients previously treated with older techniques require additional therapy. Treatment options as well as their efficiency may be influenced by previous procedures. CASE REPORT: We report a rare case of a giant treatment-resistant aneurysm in a 65-year-old woman. The aneurysm was first diagnosed due to visual disturbances in the right eye. Computed tomography angiography showed large (20 × 18 mm) wide neck aneurysm of the right internal carotid artery. The patient was subsequently treated with several methods including coiling with regular stent implantation, two flow diverter stent implantations, and hybrid neurosurgery. Full occlusion was not achieved after any of those procedures. After the last procedure (hybrid neurosurgery) the patient, in vegetative state, was transferred to the intensive care unit and then to the Health and Care Centre. CONCLUSIONS: Discussion focuses on endovascular treatment options after failure of previous treatment such as "stent in stent" technique. We conclude that three subsequent stent implantations are technically possible; however, subsequent procedures are associated with technical difficulties and their effectiveness is questionable. Ventriculoperitoneal shunt may influence the outcome of flow diversion therapy.