Long-Term Durability and Recurrence Patterns After Endovascular Treatment for Basilar Tip Aneurysms.

BACKGROUND: Treating recurrence after coil embolization of basilar tip aneurysm remains challenging even with the development of endovascular procedures. The present study evaluated long-term durability and recurrence patterns after endovascular treatment of basilar tip aneurysms. METHODS: Data of 116 consecutive patients treated with endovascular therapy at 3 regional hospitals from 2002-2019 were retrospectively analyzed. Aneurysms were ruptured in 51 cases and unruptured in 65 cases, with a mean maximal diameter of 7.8 mm (>15 mm in 14 patients) and a mean follow-up period of 5.8 ± 4.3 years. RESULTS: Recurrence was observed in 24 of the 116 patients (21%), and 14 patients were retreated. The 5-year recurrence-free survival rate was 75.3%. Cox proportional hazards analysis found that recurrence correlated significantly with maximal aneurysm diameter >10 mm (P = 0.001; hazard ratio: 3.95, 95% confidence interval: 1.76-8.90) and incomplete occlusion (P = 0.003; hazard ratio: 4.43, 95% confidence interval: 1.63-12.00). Recurrence pattern was classified into 3 types: neck type (9 patients), regrowth type (10 patients), and regrowth type of initially thrombosed aneurysms (3 patients). Rerupture occurred in neck type with de novo aneurysm formation adjacent to the neck (n = 3) and regrowth type with dome filling (n = 4). CONCLUSIONS: Recurrence after coil embolization for basilar tip aneurysms is associated with large aneurysms and incomplete occlusion at initial embolization. Understanding the patterns of recurrence is useful for predicting recurrence and selecting treatment strategies.

Angiographical Jaggy Sign of Remnant M2 Occlusion during Acute Mechanical Thrombectomy.

BACKGROUND AND PURPOSE: During mechanical thrombectomy for acute main trunk occlusion, we sometimes encounter difficult situation; 1 M2 branch of the middle cerebral artery is successfully recanalized, while the other remains occluded. In this study, we focused on the angiographical findings of remnant occlusion. METHODS: Among 83 patients who underwent mechanical thrombectomy for the acute internal carotid artery or proximal middle cerebral artery (M1) occlusion, 25 patients (30%) intraoperatively exhibited the remnant M2 occlusion, in spite of the recanalization of the other M2. We classified the angiographical findings of the remnant M2 occlusion and examined the clinical features, prognosis, and complications, in relation to additional thrombectomy. RESULTS: The remnant M2 occlusion was classified into stump type (40%, 10 cases), round deficit type (28%, 7 cases), and jaggy type (32%, 8 cases). Multivariate analysis suggested that noncardioembolic stroke may lead to jaggy type remnant occlusion with marginal significance (P = .051). Additional thrombectomy for the remnant M2 occlusion resulted in failed recanalization in 6% in the nonjaggy (stump or round deficit) type, whereas in 50% in the jaggy type groups (P = .023). Symptomatic intracranial hemorrhage occurred in 6% in the nonjaggy and 38% in the jaggy groups (P = .081), and poor outcome at discharge in 29% and in 50%, respectively. CONCLUSIONS: Angiographical jaggy sign in the remnant M2 occlusion suggests the pre-existing or procedure-related pathology, such as atherosclerosis, vasospasm, or arterial dissection. Additional thrombectomy should be carefully determined, as which might lead to adverse events and poor outcomes.

Risk Factors for Hemorrhagic and Cardioembolic Complications of Intracerebral Hemorrhage Associated with Anticoagulants.

BACKGROUND: Patients with intracerebral hemorrhage taking anticoagulants are increasingly common in Japan due to the aging population. The clinical benefit of restarting anticoagulants is established, but the optimal timing of resumption is controversial. Risk factors for hemorrhagic and cardioembolic events in the acute phase are also unknown. This study investigated hemorrhagic and cardioembolic events and risk factors in intracerebral hemorrhage patients taking anticoagulants. METHODS: The clinical data of 65 consecutive intracerebral hemorrhage patients taking anticoagulants were retrospectively reviewed. Hemorrhagic and cardioembolic complications and risk factors were analyzed. RESULTS: Lobar hemorrhage was the most frequent (21 of 65 cases, 32.3%). At discharge, 31 patients (47.7%) showed severe disability or had died. Eight (18.6%) of 43 patients who restarted anticoagulants after initial treatment developed hemorrhagic events, including recurrent intracerebral hemorrhage in 3. HAS-BLED score was 2-3 in these 3 patients. Six (15.8%) of 38 patients who took anticoagulants for cardiogenic factors suffered cardioembolism. Systemic inflammatory response syndrome was significantly more common in the cardioembolic group (66.7%) compared with the noncardioembolic group (21.9%, P < .05). CHA2DS2-VASc score was paradoxically high in the noncardioembolic group (3 versus 5, P < .05). CONCLUSION: HAS-BLED score and CHA2DS2-VASc score were not useful for risk assessment for hemorrhagic events, recurrent intracerebral hemorrhage, and cardioembolism in the acute phase. Inflammatory response might be important in the occurrence of cardioembolic events.

Predictive factors of medullary infarction after endovascular internal trapping using coils for vertebral artery dissecting aneurysms.

OBJECTIVE The first choice of treatment in cases of vertebral artery dissecting aneurysms (VADAs) is endovascular internal trapping (EIT) of the dissecting segment using coils. However, this procedure carries the risk of medullary infarction, and the risk factors for this complication are not well understood. This study investigated the risk factors causing medullary infarction. METHODS One hundred patients who underwent EIT for VADAs were included in this study. Ninety-three patients presented with subarachnoid hemorrhage. In cases involving the posterior inferior cerebellar artery (PICA), partial internal trapping targeting the ruptured site was performed to preserve the PICA. The VADAs were classified into the distal VA stump group, proximal VA stump group, and entire VA stump group, according to the location of VA segments without adequate flow-out vessels (such as the PICA [VA stump]) at risk of delayed thrombosis. The occurrence of medullary infarction was examined in each group using diffusion-weighted MRI and/or clinical symptoms. Various measurements were performed on digital subtraction angiography, and the risk factors for medullary infarction were analyzed. RESULTS Medullary infarction occurred in 30 patients, affecting the posterolateral medulla in 27 patients and the anteromedial medulla in 3 patients. Medullary infarction occurred in 3 of 47 patients (6%) in the distal VA stump group, 10 of 19 patients (53%) in the proximal VA stump group, and 17 of 34 patients (50%) in the entire VA stump group. The length of trapping was significantly longer in the infarction group than in the noninfarction group but did not differ among the 3 groups. Total length (length of trapping plus VA stump) was a risk factor for medullary infarction in the proximal VA stumps. CONCLUSIONS The primary risk factor for medullary infarction after EIT is not the length of trapping; rather, it is the anatomical location of the VADAs. The risk of medullary infarction is low in cases with distal VA stumps, but the symptoms are severe. Preservation of the origin of the anterior spinal artery can reduce the risk of medullary infarction. The risk of medullary infarction is high in cases with proximal VA stumps, but the symptoms are mild. A shorter length of trapping, although less likely to lead to complications, cannot prevent medullary infarction because the total length depends on the anatomical location of the PICA and not on the surgical technique. Reconstructive therapy should be indicated for patients with ruptured VADAs at high risk of severe ischemic complications (e.g., patients with hypoplasia of the contralateral VA or cases involving the PICA or anterior spinal artery, which are inappropriate for partial internal trapping) or for patients with unruptured VADAs.

Preoperative embolization of intracranial meningiomas using n-butyl cyanoacrylate.

INTRODUCTION: Preoperative embolization for intracranial meningioma has been controversial for several decades. This study retrospectively reviewed our experience using n-butyl cyanoacrylate (n-BCA) to identify the factors for effective devascularization and procedure-related complications. METHODS: Fifty-seven patients who underwent preoperative embolization with n-BCA were analyzed to collect the following data: age, sex, tumor size, location, pathology, and presence or absence of pial arterial supply. The predictive factors for total devascularization and complications were examined using univariate and multivariate analyses. RESULTS: Injected n-BCA penetrated into the tumor vessels in 51 cases (89%) but resulted in feeder occlusion in 6 (11%). Angiographic total devascularization was achieved in 29 cases (51%) and partial devascularization in 28 (49%). Small size, superficial location, and absence of pial supply were independent factors for total devascularization. No major complication was encountered, but asymptomatic or transient adverse events occurred in nine patients and were significantly associated with elderly patients and large tumors. CONCLUSION: Preoperative embolization for intracranial meningiomas using n-BCA can attain effective devascularization without major complications. The effect of preoperative embolization on surgical resection or patient outcome is still unknown.

Visual outcomes of endovascular and microsurgical treatment for large or giant paraclinoid aneurysms.

BACKGROUND: The optimal treatment for large or giant paraclinoid aneurysms is still controversial. The present study evaluated the results of endovascular coiling and microsurgical clipping with special reference to visual outcomes. METHODS: The clinical data and treatment outcomes of 39 cases of large (>15 mm) paraclinoid aneurysms were retrospectively reviewed. Presenting symptoms were subarachnoid hemorrhage in 16 aneurysms and visual impairment in 18. Twenty-one aneurysms were treated by endovascular therapy and 18 were treated by direct surgery. RESULTS: Maximal aneurysm diameter ≥25 mm and preoperative visual acuity <20/100 were significantly related to poor visual outcome in univariate analysis. However, preoperative visual acuity was the only significant prognostic factor in multivariate analysis (odds ratio [OR] 0.12, 95 % confidence interval [CI] 0.01-0.95, p = 0.04). Although patients treated with endovascular coiling tended to have more favorable outcome than those with surgical clipping, adjustment for other confounding factors reduced the OR of favorable outcome following each treatment modality to nearly one (OR 1.14, 95 % CI 0.17-7.46, p = 0.89). Deteriorations in the visual field showed different patterns: upper visual field deficit after endovascular coiling, and inferior nasal quadrantanopia after microsurgical clipping. CONCLUSIONS: Preoperative visual acuity was the only independent predictor of visual outcome in patients with large paraclinoid aneurysms. Although adjusted visual outcomes with microsurgical clipping and endovascular coiling were almost the same, selection of the optimal treatment for each aneurysm is essential with recognition of the potential risks and mechanisms of visual impairment.

Mattress anastomosis in micro vascular reconstruction: technical note.

BACKGROUND: Superficial temporal artery-to-middle cerebral artery (STA-MCA) anastomosis is a common procedure for neurosurgeons. The surgery necessarily requires accurate and speedy manipulation of microscope, for which a specific training is needed. Unexpected bypass occlusion sometimes happen during surgery. OBJECTIVE: Generally, conventional interrupted or continuous suture has been used for vascular anastomosis, despite various ideas have been attempted in the other surgery fields. We propose a horizontal mattress suture technique for intracranial microvascular bypass surgery. This is the first report ever published on intracranial vascular anastomosis. METHODS: We had four patients of STA-MCA bypass surgery with "mattress anastomosis" from March to May of 2012. RESULTS: During the procedure, there was no bypass occlusion and good patency was confirmed in all cases. CONCLUSION: Intimae of the recipient and the donor blood vessel contact each other precisely with this technique. Although a long-term assessment of patency is needed, it is useful for the intracranial bypass surgery.