Volume changes of extremely large and giant intracranial aneurysms after treatment with flow diverter stents

Introduction

This study assessed volume changes of unruptured large and giant aneurysms (greatest diameter >20 mm) after treatment with flow diverter (FD) stents.

Methods

Clinical audit of the cases treated in a single institution, over a 5-year period. Demographic and clinical data were retrospectively collected from the hospital records. Aneurysm volumes were measured by manual outlining at sequential slices using computerised tomography (CT) or magnetic resonance (MR) angiography data.

Results

The audit included eight patients (seven females) with eight aneurysms. Four aneurysms involved the cavernous segment of the internal carotid artery (ICA), three the supraclinoid ICA and one the basilar artery. Seven patients presented with signs and symptoms of mass effect and one with seizures. All but one aneurysm was treated with a single FD stent; six aneurysms were also coiled (either before or simultaneously with FD placement). Minimum follow-up time was 6 months (mean 20 months). At follow-up, three aneurysms decreased in size, three were unchanged and two increased. Both aneurysms that increased in size showed persistent endosaccular flow at follow-up MR; in one case, failure was attributed to suboptimal position of the stent; in the other case, it was attributed to persistence of a side branch originating from the aneurysm (similar to the endoleak phenomenon of aortic aneurysms). At follow-up, five aneurysms were completely occluded; none of these increased in volume.

Conclusion

Complete occlusion of the aneurysms leads, in most cases, to its shrinkage. In cases of late aneurysm growth or regrowth, consideration should be given to possible endoleak as the cause.     

Placement of retrievable self-expandable metallic stents with barbs into patients with obstructive prostate cancer

Objectives

To evaluate the technical feasibility and clinical effectiveness of retrievable self-expandable metallic stents with barbs in patients with obstructive prostate cancer.

Methods

Retrievable self-expandable metallic stents with eight barbs each were inserted into eight consecutive patients with obstructive prostate cancer. Patient ages ranged from 55 to 76 years (mean, 69 years). All eight patients had previously received hormone therapy, and three had undergone palliative transurethral prostatectomy. Stents were removed using a 21-F stent removal set if they caused complications.

Results

Stent placement was technically successful and well tolerated in all patients. One had severe incontinence, which improved spontaneously, and two had gross haematuria, which disappeared spontaneously within 4 days. Peak urine flow rates and post-void residual urine volumes 1 month after stent placement were 5.6–10.2 ml/s (mean, 8.3 ml/s), and 5–45 ml (mean, 27 ml), respectively. During a mean follow-up of 192 days (range, 39–632 days), one patient required stent removal after 232 days because of stone formation within the stent. No further intervention was required because the mass improved after stent removal.

Conclusions

These preliminary results suggest that retrievable stents with eight barbs are both feasible to place and effective in patients with obstructive prostate cancer.

Key Points

? Retrievable metallic urethral stents can help patients with obstructive prostate cancer. ? Retrievable self-expandable stents with eight barbs are both feasible and effective. ? These stents apparently overcome the problem of stent migration. ? Removal of these stents was safe without surgery under local anaesthesia.     

Coil embolization of intracranial saccular aneurysms using the Low-profile Visualized Intraluminal Support (LVIS™) device

Introduction

The novel Low-profile Visualized Intraluminal Support (LVIS?, LVIS and LVIS Jr.) device was recently introduced for stent-supported coil embolization of intracranial aneurysms. Periprocedural and midterm follow-up results for its use in stent-supported coil embolization of unruptured aneurysms are presented herein.

Methods

In this prospective multicenter study, clinical and radiologic outcomes were analyzed for 55 patients with saccular aneurysms undergoing LVIS-assisted coil embolization between October 2012 and February 2013. Magnetic resonance angiography or digital subtraction angiography was performed to evaluate midterm follow-up results.

Results

The standard LVIS device, deployed in 27 patients, was more often used in internal carotid artery (ICA) aneurysms (n?=?19), whereas the LVIS Jr. (a lower profile stent, n?=?28) was generally reserved for anterior communicating artery (n?=?14) and middle cerebral artery (n?=?8) aneurysms. With LVIS-assisted coil embolization, successful occlusion was achieved in 45 aneurysms (81.8 %). Although no instances of navigation failure or stent malposition occurred, segmentally incomplete stent expansion was seen in five patients where the higher profile LVIS was applied to ICA including carotid siphon. Procedural morbidity was low (2/55, 3.6 %), limited to symptomatic thromboembolism. In the imaging of lesions (54/55, 98.2 %) at 6-month follow-up, only a single instances of major recanalization (1.9 %) occurred. Follow-up angiography of 30 aneurysms (54.5 %) demonstrated in-stent stenosis in 26 (86.7 %), with no instances of stent migration. Only one patient suffered late delayed infarction (modified Rankin Scale 1).

Conclusion

The LVIS device performed acceptably in stent-assisted coil embolization of non-ruptured aneurysms due to easy navigation and precise placement, although segmentally incomplete stent expansion and delayed in-stent stenosis were issues.     

Primary Stent Angioplasty of the Inferior Vena Cava After Liver Transplantation and Liver Resection

Purpose

This study evaluated technical efficacy and safety of stent angioplasty of the inferior vena cava (IVC) after liver transplantation or liver resection and analysis of changes in creatinine levels and patients’ weight.

Methods

Between October 2004 and February 2011, 16 patients (mean age, 52.6 years) with symptomatic IVC stenoses after liver transplantation (n = 10) or liver resection (n = 6) were subjected to stent angioplasty. Enrollment criteria included edema and/or ascites. The smallest diameter of the IVC, serum creatinine values, and patients’ weight were assessed before and after stent placement and respective values were compared. Technical and clinical success, patency rates, related complications, and patients’ survival were analyzed.

Results

Stent placement was technically successful in 16 patients (100 %). Clinical success was achieved in 13 patients (81.25 %), reflecting two patients with early restenosis and one patient suffering from thrombosis distal to the stent. Mean follow-up was 372 days. Primary patencies were 75 % (n = 12). Primary assisted patencies were 93.75 % (n = 15). Serum creatinine levels decreased significantly (p = 0.01) from 1.68 mg/dl before to 1.08 mg/dl after stent placement. Patients’ weight decreased (mean 2.1 %). No angioplasty-related complications occurred.

Conclusions

Stent angioplasty of the IVC is an effective and safe treatment of stenoses after liver transplantation and resection and has a positive effect on creatinine levels.     

Long-term Results of Endovascular Stent Graft Placement of Ureteroarterial Fistula

Purpose

To evaluate the safety, efficacy, and long-term results of endovascular stent graft placement for ureteroarterial fistula (UAF).

Methods

We retrospectively analyzed stent graft placement for UAF performed at our institution from 2004 to 2012. Fistula location was assessed by contrast-enhanced computed tomography (CT) and angiography, and freedom from hematuria recurrence and mortality rates were estimated.

Results

Stent graft placement for 11 UAFs was performed (4 men, mean age 72.8 ± 11.6 years). Some risk factors were present, including long-term ureteral stenting in 10 (91 %), pelvic surgery in 8 (73 %), and pelvic radiation in 5 (45 %). Contrast-enhanced CT and/or angiography revealed fistula or encasement of the artery in 6 cases (55 %). In the remaining 5 (45 %), angiography revealed no abnormality, and the suspected fistula site was at the crossing area between urinary tract and artery. All procedures were successful. However, one patient died of urosepsis 37 days after the procedure. At a mean follow-up of 548 (range 35–1,386) days, 4 patients (36 %) had recurrent hematuria, and two of them underwent additional treatment with secondary stent graft placement and surgical reconstruction. The hematuria recurrence-free rates at 1 and 2 years were 76.2 and 40.6 %, respectively. The freedom from UAF-related and overall mortality rates at 2 years were 85.7 and 54.9 %, respectively.

Conclusion

Endovascular stent graft placement for UAF is a safe and effective method to manage acute events. However, the hematuria recurrence rate remains high. A further study of long-term results in larger number of patients is necessary.     

CT Imaging Findings and Their Relevance to the Clinical Outcomes After Stent Graft Repair of Penetrating Aortic Ulcers: Six-year, Single-center Experience

Purpose

To present the computed tomographic (CT) imaging findings and their relevance to clinical outcomes related to stent graft placement in patients with penetrating aortic ulcers (PAUs).

Methods

Medical and imaging records and imaging studies were reviewed for consecutive patients who underwent stent graft repair of a PAU. The distribution and characteristics of the PAU, technical success of stent graft repair, procedure-related complications, associated aortic wall abnormalities, and outcomes of the PAUs at follow-up CT scans were evaluated.

Results

Fifteen patients underwent endovascular treatment for PAU. A total of 87% of the PAUs were in the proximal (n?=?8) or distal (n?=?5) descending thoracic aorta. There was a broad spectrum of PAU depth (mean, 7.9?±?5.6?mm; range 1.5–25.0?mm) and diameter (mean, 13.5?±?9.7?mm; range 2.2–41.0?mm). Atherosclerosis of the thoracic aorta and intramural hematoma were associated in 53 and 93% of the patients, respectively. Technical success was achieved in 100%. Two or more stent grafts were used in five patients. Endoleaks were observed in two patients within 2?weeks of the procedure, both of which resolved spontaneously. At follow-up CT scanning, regression and thrombosis of the PAUs were observed in all patients. The average patient survival was 61.8?months, with an overall mortality of 13% (2 of 15) at follow-up. Neither death was related to the endograft device or the PAU.

Conclusion

Endovascular stent graft placement was safe and effective in causing regression and thrombosis of PAUs in this small series of patients. Two or more stent grafts were used in five patients (33%) with associated long-segmental atherosclerotic changes of the thoracic aorta or intramural hematoma.     

Biodegradable biliary stent implantation in the treatment of benign bilioplastic-refractory biliary strictures: preliminary experience

Objectives

To evaluate feasibility, safety, and outcome of patients treated with biodegradable biliary stents for benign biliary stenosis refractory to other treatments.

Methods

Between March 2011 and September 2012, ten patients (seven men, three women; age 59?±?7 years) with recurrent cholangitis due to postsurgical biliary stricture, previous multiple unsuccessful (two to five) bilioplasties, and unsuitability for surgical/endoscopic repair underwent percutaneous implantation of a biodegradable biliary stent. Patients were followed-up clinically and with ultrasound at 1, 3 and 6 months, and then at 6-month intervals.

Results

Stent implantation was always feasible. No immediate major or minor complications occurred. In all patients, 48-h cholangiographic control demonstrated optimal stent positioning and stenosis resolution. In a median follow-up time of 16.5 months (25th–75th percentiles = 11–20.25 months) no further invasive treatment was needed. Three patients experienced transient episodes of cholangitis. Neither re-stenosis nor dilatation of the biliary tree was documented during follow-up. No stent was visible at the 6-month follow-up.

Conclusions

Percutaneous placement of biodegradable biliary stents represents a new option in treating benign biliary stenoses refractory to treatment with bilioplasty. This technique seems to be feasible, effective and free from major complications. Further investigations are warranted to confirm our preliminary results.

Key Points

? Percutaneous biodegradable stents can be used to treat benign biliary stenosis. ? They can be used in patients refractory to bilioplasty. ? The procedure for insertion appears free from major complication. ? Biodegradable stents may represent an alternative device to covered expandable stents.     

Malignant Hilar Biliary Obstruction: Treatment by Means of Placement of a Newly Designed Y-Shaped Branched Covered Stent

Purpose

To evaluate the technical feasibility and clinical efficacy of placement of a newly designed Y-shaped branched covered stent for palliative treatment of malignant hilar biliary obstruction.

Methods

From June 2011 to September 2014, 34 consecutive patients with malignant hilar biliary obstruction underwent percutaneous placement of a Y-shaped branched covered stent for palliative treatment. Technical and clinical success, complications, cumulative patient survival, and stent patency were evaluated.

Results

Stent placement was technically successful in all patients. All patients showed adequate biliary drainage on the follow-up cholangiogram. Mean serum bilirubin level (10.9 mg/dl) decreased significantly 1 week (5.7 mg/dl) and 1 month (2.6 mg/dl) after stent placement (p < 0.01). Complications associated with the procedure included hemobilia (n = 3) and biloma (n = 1). During the mean follow-up period of 225 (range 12–820) days, nine patients (26.5 %) developed stent occlusion caused by tumor overgrowth (n = 8) and sludge (n = 1). Two of them underwent coaxial placement of a second stent with good results. The median survival time was 281 days and median primary stent patency was 337 days. There were no significant differences in the patient survival and stent patency rates in relation to age, sex, or Bismuth type.

Conclusion

Percutaneous placement of the Y-shaped branched covered stent seems to be technically feasible and clinically effective for palliative treatment of malignant hilar biliary obstruction.

     

Treatment of elastase-induced intracranial aneurysms in New Zealand white rabbits by use of a novel neurovascular embolization stent device

Introduction

This study aims to test a novel balloon expandable stent covered with a polytetrafluoroethylene membrane (neurovascular embolization cover (NEC), NFocus Neuromedical, Palo Alto, California) regarding angiographic and histologic aneurysm occlusion. Radiopacity, stent placement, navigation, flexibility, and intimal proliferation were also evaluated.

Methods

Eight aneurysms were induced in New Zealand white rabbits. Digital subtraction angiography (DSA) was performed directly after stent placement and after 5 and 10 min. Four and 8 weeks after stent placement, an intra-arterial DSA control was performed. The animals were then sacrificed and the aneurysms histologically evaluated.

Results

The radiopaque markers were clearly visible. Although all the stents were easily navigated into the subclavian artery, the limited flexibility of the stent resulted in straightening of the vessel in four cases. As a result, exact stent placement was achieved and acutely confirmed in only two cases. However, at sacrifice, angiographic and histologic occlusion was noted at follow-up in five aneurysms.

Conclusion

In tortuous anatomy, the relative stiffness of the stent makes exact stent placement challenging. This may have been exacerbated by the movement of the vessels due to proximity to the heart in this model. Future studies should evaluate whether existing residual flow into an aneurysm lumen might lead to embolization without any additional treatment. Anticoagulation remains a very important part of aneurysm treatment with stents. The trend toward aneurysm occlusion by excluding it from the blood circulation seems a promising method in future endovascular therapy. The NEC device shows good potential.     

Outcome of mechanical thrombectomy with Solitaire stent as first-line intra-arterial treatment in intracranial internal carotid artery occlusion

Introduction

Acute stroke from occlusion of the intracranial internal carotid artery (ICA) is associated with a poor clinical outcome despite a thrombolytic treatment. The purpose of this study was to evaluate the outcome of mechanical thrombectomy using the Solitaire stent for the treatment of acute stroke patients with intracranial ICA occlusion.

Methods

A total of 104 consecutive patients with acute stroke were treated with mechanical thrombectomy using the Solitaire stent as a first-line intra-arterial treatment. We retrospectively reviewed data from 26 of these patients who presented with acute stroke attributable to intracranial ICA occlusion. Rescue treatments in cases of failed Solitaire thrombectomy included intra-arterial urokinase, angioplasty, and forced suction thrombectomy. Successful recanalization was defined as thrombolysis in cerebral ischemia grades 2b to 3. Outcome measure was the modified Rankin Scale (mRS) score of 0–2 at 3 months.

Results

Successful recanalization was achieved in 77 % (20/26) of patients. Recanalization was achieved with the Solitaire stent alone in 69 % (18/26) of patients. Ten patients (39 %) had a good clinical outcome (mRS score of 0–2) at 3 months. There was a good outcome in 50 % of patients (10/20) with recanalization and no good outcome in patients (0/6) without recanalization (P?=?0.027). None of eight patients who received rescue treatments showed a good outcome. No symptomatic intracerebral hemorrhage occurred. Mortality was 8 % (2/26) at 3 months.

Conclusion

Mechanical thrombectomy using the Solitaire stent can achieve a high rate of successful recanalization and a very low rate of symptomatic hemorrhage and thus improve a clinical outcome in patients with acute intracranial ICA occlusion.     

Percutaneous transluminal angioplasty of a non-mainstream venous route to restore an occluded hemodialysis fistula

Purpose

To report the usefulness of percutaneous transluminal angioplasty (PTA) of a non-mainstream venous route in an occluded native hemodialysis fistula when a mainstream outflow vein could not be traversed.

Materials and methods

This cohort included seven patients with an occulted hemodialysis fistula with difficulty in traversing via a mainstream route. A non-mainstream vein near the occluded portion was traversed until it connected with a proximal large-sized vein and the route was dilated using a 4- or 5-mm balloon catheter. Metallic stent placement was performed, if necessary. Technical aspects and long-term patency was evaluated.

Results

PTA could be performed in all patients; however, stent placement was required in two because of residual stenosis and clotting. The clinical success rate of fistula restoration was 100 %. Fistula dysfunction recurred in six patients 17–668 days (mean ± standard deviation 229.3 ± 225.0) later. PTA was repeated in four patients, but not in two. The mean duration of the primary patency was 336.6 ± 417.2 days (range 17–1,190) and that of the secondary patency was 897.1 ± 801.4 days (range 17–2,230).

Conclusion

PTA of a non-mainstream venous route is useful for restoring an occluded hemodialysis fistula when the mainstream outflow vein cannot be traversed.     

Iliac Artery Stent Placement Relieves Claudication in Patients with Iliac and Superficial Femoral Artery Lesions

Purpose

To evaluate the efficacy of iliac artery stent placement for relief of claudication in patients with both iliac and superficial femoral artery (SFA) lesions.

Methods

Stent placement for only iliac artery occlusive disease was performed in 94 limbs (74 patients) with both iliac and SFA occlusive disease on the same limb. All procedures were performed because intermittent claudication did not improve after continuation of antiplatelet medication therapy and home-based exercise for 3 months. Rutherford classification was 2 in 20 limbs and 3 in 74 limbs. Patients with critical limb ischemia were excluded. Median duration of follow-up was 40 months. Primary patency rates of the iliac stent, clinical improvement rates, and risk factors for requiring additional SFA procedures were evaluated.

Results

Primary patency rates of the iliac stent at 1, 3, 5, and 7 years were 97, 93, 79, and 79 %, respectively. The initial clinical improvement rate was 87 %. Continued clinical improvement rates at 1, 3, 5, and 7 years were 87, 81, 69, and 66 %, respectively. SFA Trans-Atlantic Inter-Society Consensus (TASC) II C/D lesion was a significant risk factor for requiring additional SFA procedures.

Conclusion

Intermittent claudication was relieved by iliac stent placement in most patients with both iliac and SFA lesions. Thus, the indications for treatment of the SFA intended for claudicants should be evaluated after treatment of the iliac lesion.     

Endovascular internal carotid artery trapping for ruptured blood blister-like aneurysms: long-term results from a single centre

Introduction

Endovascular internal carotid artery (ICA) trapping was performed to treat ruptured blood blister-like aneurysms (BBAs). The aim of this study was to evaluate the procedural risks and long-term follow-up results.

Methods

The records of 11 consecutive patients with BBAs who underwent endovascular ICA trapping between 2005 and 2010 were reviewed. Clinical outcomes were assessed with modified Rankin Scale (mRS) scores.

Results

Endovascular ICA trapping was performed in 11 patients as either the primary treatment (7 patients) or the secondary treatment (4 patients) after the patient underwent other treatments. Three patients underwent superficial temporal artery (STA)-middle cerebral artery (MCA) bypass when balloon test occlusion (BTO) revealed inadequate collateral circulation. In the primary ICA trapping group (seven patients), six patients had good outcomes (mRS 0 in five, mRS 1 in one), and one patient had a poor outcome (mRS 6: dead). In the secondary ICA trapping group (four patients), two patients had good outcomes (mRS 0), and two patients had poor outcomes (mRS 4, 5). All ten of the surviving patients were clinically stable during the follow-up period (mean 39 months). A radiological follow-up of nine patients (mean 22 months) demonstrated stable occlusion, with the exception of one reopening of the ICA because of coil migration. Perfusion studies of nine patients (mean: 23 months) demonstrated no perfusion decrease.

Conclusion

Endovascular ICA trapping is an effective and durable treatment for BBAs.     

Rapid, sequential bilateral acute carotid blowout syndrome

Introduction

This study aims to report the treatment and outcome of sequential bilateral acute carotid artery blowout syndrome.

Methods

From 2004 to 2010, we treated seven male patients with sequential bilateral blowout syndrome long after irradiation treatment for head and neck cancer. After first common carotid artery (CCA)-internal carotid artery (ICA) rupture, six were treated with CCA-ICA occlusion and one with graft stenting. The contralateral ICAs were normal or stenotic on angiography in all patients. After the contralateral CCA-ICA rupture, five patients received CCA-ICA occlusion, one received graft stent treatment, and one received no treatment.

Results

Five of the seven patients died soon after the final treatment. Two patients developed cerebral infarctions (one treated with bilateral stenting, one treated with occlusion), one died from extensive local infection, one died soon after a third treatment, one died of progression of the disease, and one refused a second treatment and died soon after the diagnostic angiography. Two patients survived with follow-up periods of 1 and 5 years. In all seven patients, the contralateral CCA-ICA blowout occurred within 3 months after the first ICA occlusion.

Conclusion

Bilateral ICA occlusion is an alternative management for sequential carotid artery blowout, but the mortality is high and outcome is poor. A normal angiogram cannot exclude the possibility of rapid development of a contralateral carotid artery blowout shortly after a first episode in patients who have received radiotherapy for head and neck cancer.     

Safety and Efficacy of Percutaneous Biliary Covered Stent Placement in Patients with Malignant Biliary Hilar Obstruction; Correlation with Liver Function

Purpose

To estimate the safety and efficacy of percutaneous ePTFE-covered biliary stent placement and the relationship between underlying liver function and stent patency in patients with malignant hilar obstruction.

Materials and Methods

From March 2012 to June 2015, 41 patients [22 females, 19 males; mean age 69.8 (range 34–94) years] with malignant biliary obstruction underwent percutaneous biliary stent placement (31 patients with unilateral, 10 patients with bilateral side-by-side). Cumulative patient survival and stent patency rate curves were derived using the Kaplan–Meier method. A Cox model was used to explore the relationship between liver function and patient survival, and also biliary stent patency. Pearson correlation coefficient was used to analyze the relationship between patient survival and stent patency.

Results

Technical success rate was 100 % and clinical success rate was 95 %. During follow-up, four complications occurred (two bilomas and two cases of acute cholecystitis) and were treated successfully with percutaneous drainage. No other complication occurred. Mean serum bilirubin level was 11.34 ± 7.35 mg/dL before drainage and 5.00 ± 4.83 mg/dL 2 weeks after stent placement. The median patent survival duration was 147 days (95 % CI, 69.6–224.4 days). The median stent patency duration was 101 days (95 % CI, 70.0–132.0 days). The cumulative stent patency rates at 1, 3, 6, and 12 months were 97, 57.6, 30.3, and 17.0 %, respectively. Child–Pugh score was correlated significantly with patient survival (P = 0.011) and stent patency (P = 0.007). MELD score was correlated significantly with stent patency (P = 0.044). There was a correlation between patient survival and stent patency (r = 0.778, P < 0.001).

Conclusion

Percutaneous placement of ePTFE-covered biliary stent was a safe and an effective method for malignant biliary obstruction. Underlying liver function seemed to be one of the important factors affecting patient survival and stent patency, and stent patency showed statistically significant correlation with patient survival.

     

Percutaneous Intraductal Radiofrequency Ablation is a Safe Treatment for Malignant Biliary Obstruction: Feasibility and Early Results

Purpose

Previous clinical studies have shown the safety and efficacy of this novel radiofrequency ablation catheter when used for endoscopic palliative procedures. We report a retrospective study with the results of first in man percutaneous intraductal radiofrequency ablation in patients with malignant biliary obstruction.

Methods

Thirty-nine patients with inoperable malignant biliary obstruction were included. These patients underwent intraductal biliary radiofrequency ablation of their malignant biliary strictures following external biliary decompression with an internal-external biliary drainage. Following ablation, they had a metal stent inserted.

Results

Following this intervention, there were no 30-day mortality, hemorrhage, bile duct perforation, bile leak, or pancreatitis. Of the 39 patients, 28 are alive and 10 patients are dead with a median survival of 89.5 (range 14–260) days and median stent patency of 84.5 (range 14–260) days. One patient was lost to follow-up. All but one patient had their stent patent at the time of last follow-up or death. One patient with stent blockage at 42 days postprocedure underwent percutaneous transhepatic drain insertion and restenting. Among the patients who are alive (n = 28) the median stent patency was 92 (range 14–260) days, whereas the patients who died (n = 10) had a median stent patency of 62.5 (range 38–210) days.

Conclusions

In this group of patients, it appears that this new approach is feasible and safe. Efficacy remains to be proven in future, randomized, prospective studies.     

Endovascular Treatment of Infrarenal Abdominal Aortic Lesions With or Without Common Iliac Artery Involvement

Purpose

To evaluate the results of stent placement for obstructive atherosclerotic aortic disease with or without involvement of the common iliac artery.

Materials and Methods

Forty patients had self-expanding stents primarily or after balloon dilatation in the abdominal aorta between January 2005 and May 2011. All patients had trouble walking. Follow-up examinations were performed with clinical visits; these included color Doppler ultrasonography and computed tomographic angiography.

Results

Technical, clinical, and hemodynamic success was achieved in all patients. None of the patients underwent reintervention during the follow-up period, which ranged from 3 months to 6 years (median 24 months). Nine complications occurred in six patients. Of the nine complications, four were distal thromboembolisms, which were successfully treated with catheter-directed thrombolysis or anticoagulation therapy.

Conclusion

Endovascular treatment of the obstructive aortic disease using self-expanding stents was safe and effective, with high technical success and long-term patency. Thromboembolic complications were high even though direct stenting was considered protective for thromboembolism formation. Particularly for infrarenal aortic stenosis, it can be recommended as the first-line treatment option for patients with obstructive atherosclerotic aortic disease.     

Stent placement versus angioplasty for hepatic artery stenosis after liver transplant: a meta-analysis of case series

Background

Hepatic artery stenosis (HAS) is a serious complication of liver transplantation but data on the most effective endovascular management are lacking. We aimed to compare percutaneous balloon angioplasty (PBA) with stent placement.

Methods

We searched MEDLINE, Cochrane, Web of Science, EMBASE, SCOPUS, and Biosis Previews between 1970 and December 2011 and performed meta-analysis of short-term (procedural success, complications) and long-term outcomes (liver function, arterial patency, survival, re-intervention, re-transplantation). Random effects models were used for the analysis and meta-regression performed for the year of study.

Results

A total of 263 liver transplants in 257 patients [age 43 (±8) years] underwent 147 PBAs and 116 stents. Transplanted livers were from deceased donors in 240 (91 %). Follow-up was 1 month to 4.5 years (median 17 months). PBA and stent had similar procedural success (89 % vs. 98 %), complications (16 % vs. 19 %), normal liver function tests (80 % vs. 68 %), arterial patency (76 % vs. 68 %), survival (80 % vs. 82 %), and requirement for re-intervention (22 % vs. 25 %) or re-transplantation (20 % vs. 24 %) (P non-significant). In the most recent studies re-transplantation was reported less compared to older series (P?=?0.04).

Conclusion

Both PBA and stent offer comparable results for HAS. These techniques have contributed to a recent decline in re-transplantation.

Key Points

? Interventional radiological procedures are often used to treat post-transplant hepatic artery stenosis. ? Meta-analysis shows that percutaneous balloon angioplasty and stent placement are both efficacious. ? Percutaneous balloon angioplasty and stent placement appear to have similar complication rates. ? Re-transplantation rates have declined, partly due to interventional management for arterial stenosis.     

Frequency and predictors of endoleaks and long-term patency after covered stent placement for the treatment of intracranial aneurysms: a prospective, non-randomised multicentre experience

Objective

We investigated immediate/late endoleaks and long-term patency following stent-graft placement for treatment of intracranial aneurysms located within the distal internal carotid artery (ICA) or vertebral artery (VA).

Methods

Forty-five aneurysms in 41 patients receiving covered stents in three centres were followed. Outcome measures included aneurysm occlusion rate, endoleaks, late in-stent stenosis rate, clinical improvement, neurological deficiencies and death.

Results

Total aneurysm exclusion was achieved in 69.2% (n?=?27), with 30.8% (n?=?12) experiencing immediate residual endoleaks. Angiographic follow-up (mean 43.5?±?14.3 months) revealed that 87.2% (n?=?34) were completely occluded with only 12.8% (n?=?5) showing residual endoleaks. Predictors of immediate endoleaks in our patient group were stent number (P?=?0.023) and stent diameter (P?=?0.022), while predictors of late endoleaks in our patient group were stent diameter (P?=?0.035) and stent angulation (P?=?0.021). Late in-stent stenosis rates were 18.0?±?13.3 and 29.0?±?18.5% compared with the period immediately following implantation at 2- and 6-year follow-ups respectively. Smoking (P?=?0.017) and stent angulation (P?=?0.020) were predictors of late in-stent stenosis.

Conclusion

Treating intracranial aneurysms with Willis stent-grafts has an acceptable immediate and late occlusion rate and long-term stented artery patency rate.

Key Points

? Covered stents can be a treatment option for intracranial aneurysms. ? Technical success for treating distal ICA and VA aneurysms can reach 97.6%. ? However immediate and late endoleaks occur in 30.8 and 12.8% respectively. ? The number, diameter and angulation of stents are possible predictors of endoleaks. ? Smoking and stent angulation seem to predict late in-stent stenosis.     

Modified protection using far proximal portion of self-expandable closed-cell stents for embolization of wide-necked intracranial aneurysms

Introduction

Stent-assisted embolization is sometimes limited in wide-necked aneurysms involving the acute-angled origins of tortuous branching arteries, and occasionally, Y-shaped stenting is required to remedy the sweeping effects of a broad aneurysmal neck on arterial branches. Described herein is a modified stent-assisted coil embolization technique entailing strategic placement of far proximal stent (“distal stenting”) as an alternate approach in such scenarios.

Methods

For this particular technique, stent placement is confined to a branch artery, allowing far proximal stent to cover aneurysmal neck, with no bridge to parent artery. Kinking of stents deployed in tortuous arteries is thereby avoided, and better coverage of aneurysmal neck is achieved, compared with traditional stent protection. Records of 12 consecutive patients with wide-necked aneurysms, all treated by coil embolization with distal stenting between January 2009 and February 2014, were retrieved from a prospective data repository at our institution. Outcomes were analyzed in terms of morphologic features and clinical status.

Results

This modified technique was largely applied to aneurysms of middle cerebral artery, followed by posterior communicating artery and anterior communicating artery sites. With one exception, all aneurysms treated were successfully occluded. There were no complications directly related to distal stenting. At final follow-up (mean interval, 16.8?±?9.7 months), complete aneurysmal occlusion was sustained in 81.8 %. Delayed stent migration was observed in one patient (8.3 %).

Conclusion

Our study suggests that distal stenting in wide-necked aneurysms is a reasonable alternative to traditional stent protection, despite the potential for delayed stent migration.