First-Pass Recanalization with EmboTrap II in Acute Ischemic Stroke (FREE-AIS): A Multicenter Prospective Study.

OBJECTIVE: We aimed to evaluate the efficacy of EmboTrap II in terms of first-pass recanalization and to determine whether it could yield favorable outcomes. MATERIALS AND METHODS: In this multicenter, prospective study, we consecutively enrolled patients who underwent mechanical thrombectomy using EmboTrap II as a front-line device. The primary outcome was the first pass effect (FPE) rate defined by modified Thrombolysis In Cerebral Infarction (mTICI) grade 2c or 3 by the first pass of EmboTrap II. In addition, modified FPE (mFPE; mTICI grade 2b-3 by the first pass of EmboTrap II), successful recanalization (final mTICI grade 2b-3), and clinical outcomes were assessed. We also analyzed the effect of FPE on a modified Rankin Scale (mRS) score of 0-2 at 3 months. RESULTS: Two hundred-ten patients (mean age ± standard deviation, 73.3 ± 11.4 years; male, 55.7%) were included. Ninety-nine patients (47.1%) had FPE, and mFPE was achieved in 150 (71.4%) patients. Successful recanalization was achieved in 191 (91.0%) patients. Among them, 164 (85.9%) patients underwent successful recanalization by exclusively using EmboTrap II. The time from groin puncture to FPE was 25.0 minutes (interquartile range, 17.0-35.0 minutes). Procedure-related complications were observed in seven (3.3%) patients. Symptomatic intracranial hemorrhage developed in 14 (6.7%) patients. One hundred twenty-three (58.9% of 209 completely followed) patients had an mRS score of 0-2. Sixteen (7.7% of 209) patients died during the follow-up period. Patients who had successful recanalization with FPE were four times more likely to have an mRS score of 0-2 than those who had successful recanalization without FPE (adjusted odds ratio, 4.13; 95% confidence interval, 1.59-10.8; p = 0.004). CONCLUSION: Mechanical thrombectomy using the front-line EmboTrap II is effective and safe. In particular, FPE rates were high. Achieving FPE was important for an mRS score of 0-2, even in patients with successful recanalization.

Clinical outcomes of rescue stenting for failed endovascular thrombectomy: a multicenter prospective registry.

BACKGROUND: Mechanical thrombectomy (MT) is a primary endovascular modality for acute intracranial large vessel occlusion. However, further treatment, such as rescue stenting, is occasionally necessary for refractory cases. We aimed to investigate the efficacy and safety of rescue stenting in first-line MT failure and to identify the clinical factors affecting its clinical outcome. METHODS: A multicenter prospective registry was designed for this study. We enrolled consecutive patients who underwent rescue stenting for first-line MT failure. Endovascular details and outcomes, follow-up patency of the stented artery, and clinical outcomes were summarized and compared between the favorable and unfavorable outcome groups. RESULTS: A total of 78 patients were included. Intracranial atherosclerotic stenosis was the most common etiology for rescue stenting (97.4%). Seventy-seven patients (98.7%) were successfully recanalized by rescue stenting. A favorable outcome was observed in 66.7% of patients. Symptomatic intracranial hemorrhage and mortality were observed in 5.1% and 4.0% of patients, respectively. The stented artery was patent in 82.1% of patients on follow-up angiography. In a multivariable analysis, a patent stent on follow-up angiography was an independent factor for a favorable outcome (OR 87.6; 95% CI 4.77 to 1608.9; p=0.003). Postprocedural intravenous maintenance of glycoprotein IIb/IIIa inhibitor was significantly associated with the follow-up patency of the stented artery (OR 5.72; 95% CI 1.45 to 22.6; p=0.013). CONCLUSIONS: In this multicenter prospective registry, rescue stenting for first-line MT failure was effective and safe. For a favorable outcome, follow-up patency of the stented artery was important, which was significantly associated with postprocedural maintenance of glycoprotein IIb/IIIa inhibitors.

Microsurgical efficacy and safety of a right-hemispheric approach for unruptured anterior communicating artery aneurysms.

OBJECTIVE: We investigated the effectiveness of a right hemispheric surgical approach in treating unruptured anterior communicating artery aneurysms. METHODS: Between January 2005 and June 2012, 305 patients with anterior communicating artery (Acom) aneurysms were treated using the pterional approach. Among them, 113 who underwent microsurgery with an unruptured Acom aneurysm were enrolled in this study. Every patient was evaluated with digital subtraction angiography preoperatively and CT scans were taken several times postoperatively. Surgical outcomes and complications were evaluated at discharge using the Glasgow Outcome Scale and at 6 months after surgery with CT angiography. RESULTS: Enrolled patients included 55 males and 58 females with a mean age of 56.3 years (range: 30-75 years). The mean diameter of the aneurysm was 5.8mm (range: 1.9-24.1). Left A1 dominancy was found in 71 patients (62.8%) whereas right A1 dominancy was found in 20 patients (17.7%), and right pterional craniotomies were performed in 92 patients (81.4%) while left pterional craniotomies were performed in 21 patients (18.6%). Complete clip application was achieved in 94.9% of patients (74 of 78) in right-side approach group but in only 81.3% of patients (13 of 16) in left-side approach group. Despite a left A1 dominancy and approached from the right, more than 90% of the patients had an excellent outcome at discharge (GOS 5) and more than 90% a complete aneurysm clipping at the 6-month follow-up CT angiography although it was not statistically significant. CONCLUSION: Microsurgical clipping of the unruptured Acom aneurysm through a right-side surgical approach showed favorable postoperative clinical and anatomical outcomes, especially aneurysms smaller than 10mm.

Relationship between Two Types of Coil Packing Densities Relative to Aneurysm Size.

BACKGROUND AND PURPOSE: Coil packing density (PD) can be calculated via a formula (PDF ) or software (PDS ). Two types of PD can be different from each other for same aneurysm. This study aimed to evaluate the interobserver agreement and relationships between the 2 types of PD relative to aneurysm size. METHODS: Consecutive 420 saccular aneurysms were treated with coiling. PD (PDF , [coil volume]/[volume calculated by formula] and PDS, [coil volume]/[volume measured by software]) was calculated and prospectively recorded. Interobserver agreement was evaluated between PDF and PDS . Additionally, the relationships between PDF and PDS relative to aneurysm size were subsequently analyzed. RESULTS: Interobserver agreement for PDF and PDS was excellent (Intraclass correlation coefficient, PDF ; 0.967 and PDS ; 0.998). The ratio of PDF and PDS was greater for smaller aneurysms and converged toward 1.0 as the maximum dimension (DM ) of aneurysm increased. Compared with PDS , PDF was overestimated by a mean of 28% for DM < 5 mm, by 17% for 5 mm ≤ DM < 10 mm, and by 9% for DM ≥ 10 mm (P < 0.01). CONCLUSIONS: Interobserver agreement for PDF and PDS was excellent. However, PDF was overestimated in smaller aneurysms and converged to PDS as aneurysm size increased.

Coil embolization of overwide and undertall small intracranial aneurysms with double microcatheter technique.

BACKGROUND: Overwide and undertall small intracranial aneurysms remain a challenge for coil embolization. The purpose of this study is to evaluate the feasibility and results of intrasaccular double microcatheter endovascular coil embolization of overwide and undertall small intracranial aneurysms. METHODS: Small (<7 mm), overwide (dome-to-neck ratio [DNR] ≤1.2), and undertall (ASPECT ratio ≤1.2) aneurysms which were treated with double microcatheter technique were selected. For the double microcatheter technique, two microcatheters were selected simultaneously into the aneurysm sac and coil insertion was performed alternatingly. The initial results, ASPECT, DNR ratios, complications, and follow-up results were assessed. RESULTS: Twenty small (mean, 3.8 mm), overwide (mean DNR, 1.1), and undertall (mean ASPECT, 1.0) aneurysms were treated with the double microcatheter technique. Overall, complete or near complete occlusion was achieved in 19/20 cases. This was achieved with only the double microcatheter technique in 16/20 cases (ASPECT mean, 1.0; DNR mean, 1.1). Adjuvant balloon remodeling was performed in 4/20 cases (ASPECT mean, 0.8; DNR mean, 1.1). The ASPECT ratio was significantly lower in the adjuvant balloon remodeling cases (p = 0.027). Coiling failed in one patient with both DNR and ASPECT ratio <1.0. Overall, one patient developed a focal visual field defect after the procedure. No other patients developed neurologically significant complications. CONCLUSIONS: Double microcatheter technique may be a safe and effective method for the treatment of overwide and undertall small intracranial aneurysms.

Spinous process morphometry for interspinous device implantation in Korean patients.

OBJECTIVE: To analyze the interspinous distance and the height, length, and thickness of the lumbar spinous process for interspinous device implantation in Korean patients. METHODS: Morphometric data obtained from plain radiographs of the lumbar and sacral spine were analyzed. The study included 60 matched subjects who visited an outpatient clinic for back pain. Exclusion criteria included collapsed intervertebral disc, lumbarization, and sacralization. There were 34 men and 26 women; age range was the 20s to 70s, with 10 subjects in each decade. The interspinous distance and height, length, and thickness of the lumbar spinous process were obtained on lateral radiographs using an image analysis program (M-view 5.4; Marotech). RESULTS: The largest interspinous distance was at L2-3, with a mean of 12 mm (range 6-22 mm), and the smallest distance was at L5-S1, with a mean of 8 mm (range 3-16 mm). The interspinous distance became shorter from L1-2 to L5-S1. A negative correlation was noted between age and interspinous distance in the L1-5 levels (L1-2, y=-0.11x+17.27, r2=0.34, P<0.0001; L2-3, y=-0.07x+15.68, r2=0.12, P=0.0058; L3-4, y=-0.08x+14.39, r2=0.27, P<0.0001; L4-5, y=-0.05x+11.65,r2=0.096, P=0.0158; L5-S1, y=-0.02x+9.25, r2=0.028, P=0.1982). CONCLUSIONS: There is a decreasing trend in the interspinous distance in the L1-5 levels with advancing years. Taking progressive collapse of the interspinous distance with the aging process into consideration, interspinous implants should be carefully selected in younger patients.

Characteristics and management of residual or slowly recurred intracranial aneurysms.

OBJECTIVE: Residual aneurysm from incomplete clipping or slowly recurrent aneurysm is associated with high risk of subarachnoid hemorrhage. We describe complete treatment of the lesions by surgical clipping or endovascular treatment. METHODS: We analyzed 11 patients of residual or recurrent aneurysms who had undergone surgical clipping from 1998 to 2009. Among them, 5 cases were initially clipped at our hospital. The others were referred from other hospitals after clipping. The radiologic and medical records were retrospectively analyzed. RESULTS: All patients presented with subarachnoid hemorrhage at first time, and the most frequent location of the ruptured residual or recurrent aneurysm was in the anterior communicating artery to posterior-superior direction. Distal anterior cerebral artery, posterior communicating artery, and middle cerebral artery was followed. Repositioning of clipping in eleven cases, and one endovascular treatment were performed. No residual aneurysm was found in postoperative angiography, and no complication was noted in related to the operations. CONCLUSION: These results indicate the importance of postoperative or follow up angiography and that reoperation of residual or slowly recurrent aneurysm should be tried if such lesions being found. Precise evaluation and appropriate planning including endovascular treatment should be performed for complete obliteration of the residual or recurrent aneurysm.