3D exoscopic versus microscopic superficial temporal artery to middle cerebral artery bypass surgery for moyamoya disease - a comparative series.

PURPOSE: Superficial temporal artery to middle cerebral artery (STA-MCA) direct bypass surgery is the most common surgical procedure to treat moyamoya disease (MMD). Here, we aim to compare the performance of the 3D exoscope in bypass surgery with the gold standard operative microscope. METHODS: All direct STA-MCA bypass procedures performed at a single university hospital for MMD between 2015 and 2023 were considered for inclusion. Data were retrospectively collected from patient files and surgical video material. From 2020 onwards, bypass procedures were exclusively performed using a digital three-dimensional exoscope as visualization device. Results were compared with a microsurgical bypass control group (2015-2019). The primary endpoint was defined as total duration of surgery, duration of completing the vascular anastomosis (ischemia time), bypass patency, number of stiches to perform the anastomosis, added stiches after leakage testing of the anastomosis and the Glasgow outcome scale (GOS) at last follow-up as secondary outcome parameter. RESULTS: A total of 16 consecutive moyamoya patients underwent 21 STA-MCA bypass procedures. Thereof, six patients were operated using a microscope and ten patients using an exoscope (ORBEYE® n = 1; AEOS® n = 9). Total duration of surgery was comparable between devices (microscope: 313 min. ± 116 vs. exoscope: 279 min. ± 42; p = 0.647). Ischemia time also proved similar between groups (microscope: 43 min. ± 19 vs. exoscope: 41 min. ± 7; p = 0.701). No differences were noted in bypass patency rates. The number of stiches per anastomosis was similar between visualization devices (microscope: 17 ± 4 vs. exoscope: 17 ± 2; p = 0.887). In contrast, more additional stiches were needed in microscopic anastomoses after leakage testing the bypass (p = 0.035). CONCLUSION: Taking into account the small sample size, end-to-side bypass surgery for moyamoya disease using a foot switch-operated 3D exoscope was not associated with more complications and led to comparable clinical and radiological results as microscopic bypass surgery.

Long-term feasibility of the new sutureless excimer laser-assisted non-occlusive anastomosis clip in a pig model.

BACKGROUND: High flow bypass surgery can be a last resort procedure for patients suffering from complex neurovascular pathology. Temporary occlusion of a recipient artery in these patients could result in debilitating neurological deficits. We developed a sutureless, mechanical anastomotic connection device, the SELANA clip (Sutureless Excimer Laser-Assisted Non-occlusive Anastomosis clip: SEcl). In the present study, we aim to determine the long-term non-inferiority of the SEcl technique compared with historical data of the conventional ELANA anastomosis technique. METHODS: A total of 18 SEcl bypasses were created on the carotid artery in a porcine model in 6 different survival groups. Mean application times, flap retrieval rates, hemostasis, patency, flow, endothelialization, and remodeling were assessed. RESULTS: The mean application time of the SEcl anastomoses was 15.2 ± 9.6 min, which was faster compared with the conventional ELANA anastomoses. The flap retrieval rate of the SEcl anastomoses was 86% (32/37). Direct hemostasis was achieved in 89% (33/37) SEcl anastomoses. Patency in all surviving animals was 94% (17/18). Bypass flow after six months was 156.5 ± 24.7 mL/min. Full endothelialization of the SEcl pins was observed after 3 weeks. CONCLUSION: The SEcl technique is not inferior to the ELANA technique regarding patency, flap retrieval rate, flow, and endothelialization. On the basis of a significantly shorter application time and superior hemostasis, the SEcl technique could be preferable over the ELANA technique. A pilot study in patients is a logical next step based on our current results.

Additional Revascularization Using Multiple Burr Holes for PCA Involvement in Moyamoya Disease.

In specific cases of moyamoya disease (MMD), posterior cerebral artery (PCA) stenosis can develop after treatment of the anterior circulation and require additional revascularization. Here, we report two cases that underwent additional posterior indirect revascularization with multiple burr holes for PCA involvement after bilateral revascularization treatment of the anterior circulation. They presented with transient ischemic attack even after bilateral superficial temporal artery-middle cerebral artery bypass, and magnetic resonance angiography (MRA) showed that PCA stenosis had worsened. Indirect revascularization with multiple burr holes using Benz-marked skin incisions was performed. After surgery, the symptoms improved without perioperative complications, and cerebral angiography showed collateral circulation via the burr hole. Indirect revascularization for MMD is often combined with direct revascularization, and there are only a few reports on the use of multiple burr hole surgery alone. In addition, there are few reports of posterior circulation, despite the emphasis on the importance of PCA involvement in MMD. Indirect revascularization with multiple burr holes alone can be performed in multiple areas and applied to patients who cannot undergo direct revascularization using the occipital artery. The procedure is simple and less invasive than traditional direct revascularization procedures. Therefore, it can be effective, especially in pediatric cases of MMD with PCA involvement.

Does Device Selection Impact Recanalization Rate and Neurological Outcome?: An Analysis of the Save ChildS Study.

Background and Purpose- The recent Save ChildS study provides multicenter evidence for the use of mechanical thrombectomy in children with large vessel occlusion arterial ischemic stroke. However, device selection for thrombectomy may influence rates of recanalization, complications, and neurological outcomes, especially in pediatric patients of different ages. We, therefore, performed additional analyses of the Save ChildS data to investigate a possible association of different thrombectomy techniques and devices with angiographic and clinical outcome parameters. Methods- The Save ChildS cohort study (January 2000-December 2018) analyzed data from 27 European and United States stroke centers and included all pediatric patients (<18 years), diagnosed with arterial ischemic stroke who underwent endovascular recanalization. Patients were grouped into first-line contact aspiration (A Direct Aspiration First Pass Technique [ADAPT]) and non-ADAPT groups as well as different stent retriever size groups. Associations with baseline characteristics, recanalization rates (modified Treatment in Cerebral Infarction), complication rates, and neurological outcome parameters (Pediatric National Institutes of Health Stroke Scale after 24 hours and 7 days; modified Rankin Scale and Pediatric Stroke Outcome Measure at discharge, after 6 and 24 months) were investigated. Results- Seventy-three patients with a median age of 11.3 years were included. Currently available stent retrievers were used in 59 patients (80.8%), of which 4×20 mm (width×length) was the most frequently chosen size (36 patients =61%). A first-line ADAPT approach was used in 7 patients (9.6%), and 7 patients (9.6%) were treated with first-generation thrombectomy devices. In this study, a first-line ADAPT approach was neither associated with the rate of successful recanalization (ADAPT 85.7% versus 87.5% No ADAPT) nor with the complication rate or the neurological outcome. Moreover, there were no associations of stent retriever sizes with rates of recanalization, complication rates, or outcome parameters. Conclusions- Our study suggests that neurological outcomes are generally good regardless of any specific device selection and suggests that it is important to offer thrombectomy in eligible children regardless of technique or device selection. Registration- URL: https://www.drks.de/; Unique identifier: DRKS00016528.

How I do it: superficial temporal artery to middle cerebral artery bypass for treatment of giant middle cerebral artery aneurysm.

BACKGROUND: Giant middle cerebral artery aneurysms are frequently anatomically complicated. Trapping may yield poor outcome, and bypass revascularization is often necessary as an adjunctive treatment to preserve flow. METHOD: The technical nuances of superficial temporal artery to middle cerebral artery bypass are described in the setting of clip reconstruction of giant middle cerebral artery (MCA) aneurysm. In addition to an operative video, the anatomy and surgical technique are demonstrated in virtual reality to enhance the didactic clarity. CONCLUSION: Meticulous technique is paramount for successful superficial temporal artery MCA bypass. Along with clip reconstruction, it is a critical part of the treatment of complex, giant MCA aneurysms.

Feasibility of the new sutureless excimer laser-assisted non-occlusive anastomosis clip in a rabbit model.

BACKGROUND: The excimer laser-assisted non-occlusive anastomosis (ELANA) technique facilitates the construction of anastomoses without temporary occlusion of the recipient artery. Experiments aimed at simplifying the technique eventually resulted in a sutureless ELANA slide (SEsl) anastomosis. After the first clinical use, new insights lead to the application of a clip at the back of the device, the SELANA clip (SEcl). The SEcl offers a distinct advantage over the SEsl since no sealant is necessary. In this study, we determine the feasibility of the SEcl anastomosis in an in vivo rabbit model. METHODS: 15 SEcl anastomoses and 15 conventional ELANA anastomoses were created on the abdominal aorta in 5 rabbits. Mean application times, flap retrieval rates, hemostasis, and burst pressures were assessed. RESULTS: The mean application time of the SEcl anastomoses was 11.4 min versus 39.0 min for the ELANA anastomoses (mean difference, 27.6 min; 95% CI, 20.6-34.7). The flap retrieval rate of the SEcl anastomoses (14/15) was not inferior to the flap retrieval rate of the ELANA anastomoses (13/15). Direct hemostasis was achieved in 13/15 (87%) SEcl anastomoses and in 14/15 (94%) ELANA anastomoses. All SEcl anastomoses were resistant to provoked pressures until 250 mmHg. CONCLUSION: The SEcl anastomosis is technically feasible in in vivo experiments. Mean application time, flap retrieval rate, hemostasis, and burst pressure are not inferior to the conventional ELANA anastomosis. Further long term experiments should be performed to assess safety, patency, and reendothelialization.

STA-enhanced vascularized galeal flap for revascularization of moyamoya disease: technical report.

BACKGROUND: A variety of revascularization techniques have been reported for the management of moyamoya disease to prevent risks of stroke. STA (superficial temporal artery)-MCA (middle cerebral artery) microanastomosis, single or double bypass, with temporal muscle or galeal onlay graft has been the standard operative procedure. METHOD: Our rationale of revascularization surgery has been a combination of STA-MCA double bypass using the frontal and the parietal branches of STA and transfer of a highly vascularized thick galeal flap with maintained STA vasculature. CONCLUSION: This STA-enhanced vascularized galeal flap graft is extremely effective for revascularization of moyamoya disease.

Natural Y-shaped radial artery graft bypass for a complex middle cerebral artery aneurysm: A case report.

Giant thrombosed middle cerebral artery (MCA) aneurysms are difficult to treat and sometimes require complex revascularization using allografts. We describe a technical method using revascularization with a natural Y-shaped graft that provides a normal variation for a complex MCA aneurysm. A 65-year-old man with a giant thrombosed MCA aneurysm presented with right hemiparesis and aphasia. The patient had a history of clipping surgery for the ipsilateral side of the MCA aneurysm 25 years before, and a de novo aneurysm developed over the previous 18 years. For the giant thrombosed aneurysm, trapping and revascularization were performed. A natural radial artery Y-graft was used as the graft and anastomosed to both M2 trunks. The symptoms improved after surgery, and the patient was discharged 3 weeks later. This is the first report of a double-barrel bypass using a natural Y-graft. This method attained a normal variation, and the flow of the Y-graft was physiological. For the radical cure of giant thrombosed MCA aneurysms, multiple revascularizations might be required. With this natural Y-graft, complex transpositions could be avoided.

Early and midterm results of treatment of giant internal carotid artery paraclinoid aneurysms with trapping and flow diverters.

BACKGROUND: Flow diverter devices (FDD) carry risks of postoperative complications when treating aneurysms with wide necks, stenosis, and severe tortuosity of the parent vessel. In this study, we evaluated early and midterm results for the treatment of giant paraclinoid aneurysms managed by trapping and endovascular deployment of FDD. METHODS: Medical records were analyzed for patients with giant paraclinoid aneurysms treated between July 2008 and December 2017 at National Centre for Neurosurgery with either a flow diverter or by trapping the aneurysm with or without extracranial-intracranial (EC-IC) bypass surgery. We recorded age, sex, clinical presentation, treatment modality, morbidity, and mortality. Clinical outcomes were assessed using a modified Rankin scale (mRS). RESULTS: Among 29 consecutive patients, 13 were treated with FDD, and 16 patients were managed by trapping the aneurysm, where 7/16 cases had preliminary EC-IC bypass. Of 16 trapping patients, six were trapped endovascularly and ten were trapped surgically. During the follow-up period (mean 33 months, range 6-96), total exclusion of the aneurysm from the circulation was observed 100% of aneurysms in the trapping group and 84.6% in the FDD group (P = 0.192). Early postoperative morbidity was observed in three (23%) cases in the FDD group, and four (25%) in trapping group (P = 0.525). The FDD group had one (7.7%) fatal complication due to stent occlusion and severe ischemic stroke after three months postoperatively, despite appropriate antiplatelet therapy. There were no mortalities in the trapping group (P = 0.149). The rate of mRS 0-2 did not differ significantly across groups at discharge (81.3% vs. 69.2%; P = 0.667), and all patients had mRS 0-2 at follow-up (P = 1.000). CONCLUSIONS: FDD deployment for giant paraclinoid aneurysms results in comparable angiographic and clinical outcomes to aneurysm trapping. Despite implementation of modern endovascular treatment methods, aneurysm trapping remains a valuable treatment option in carefully selected patients with giant paraclinoid aneurysms.

Mechanical thrombectomy of M2 occlusions with distal access catheters using ADAPT.

BACKGROUND AND PURPOSE: The direct aspiration first pass technique (ADAPT) using distal access catheters (DAC) has proven to be an effective and safe endovascular treatment strategy of acute ischemic stroke with large vessel occlusions (LVO). However, data about direct aspiration using DAC in M2 segment occlusions is limited. We assess the safety and efficacy of DACs in acute M2 occlusions using ADAPT with large bore (5 French /6 French) aspiration catheters as the primary method for endovascular recanalization. MATERIALS AND METHODS: From January 2017 to July 2018, 52 patients with an acute ischemic stroke due to M2 occlusions underwent mechanical thrombectomy using ADAPT with DACs (SOFIA 5 French/Catalyst 6) as frontline therapy. Patient demographics, technical parameters and outcome data were recorded. RESULTS: Median National Institutes of Health Strokes Scale (NIHSS) Score was 12 at admission. Successful revascularization to mTICI 2b-3 with ADAPT alone was achieved in 45 of 52 patients (86.5%) with mTICI 3 achieved in 32 patients (61.5%). Additional stent retrievers were used in 6 patients and led to an overall successful revascularisation of 92.3% (48/52). Median NIHSS at discharge was 4. 29 of 52 (55.8%) patients had a modified Rankin Scale (mRS) Score 0-2 at three months. Symptomatic intracranial hemorrhage did not occur. CONCLUSION: DACs can safely be used for mechanical thrombectomy of acute M2 occlusions by the ADAPT approach. Their use alone can be a high efficacious treatment of distal intracranial thromboembolic occlusions.

Preclinical success but clinical failure of the sutureless excimer laser-assisted non-occlusive anastomosis (SELANA) slide.

BACKGROUND: The excimer laser-assisted non-occlusive anastomosis (ELANA) has been developed for intracranial bypass without the need for temporary recipient occlusion. We designed and tested a sutureless variant of the ELANA-the SELANA slide (SEsl). OBJECTIVE: This study aims to evaluate the SEsl preclinical results and describe its first clinical application. METHODS: First, in a cadaver study, 28 SEsl anastomoses were compared with 28 ELANA anastomoses. Second, in an acute rabbit model, 90 SEsl anastomoses were compared with 30 ELANA anastomoses. Finally, in a surviving pig model, 38 SEsl bypasses were created. To evaluate the clinical efficacy of the SEsl, we then treated one patient with a giant, right-sided middle cerebral artery (MCA) aneurysm with an intracranial-intracranial SEsl bypass and parent vessel occlusion. RESULTS: In preclinical studies, the SEsl anastomosis was shown to be equivalent or superior to the ELANA in terms of associated ease, patency, and bleeding complications. However, clinical application in rigid and arteriosclerotic receiving arteries was problematic. Although bypass creation and aneurysm occlusion were technically successful and the patient was postoperatively well, a pseudoaneurysm formed postoperatively at the internal carotid artery anastomosis and bled. Subsequent treatment failed and the patient did not survive. CONCLUSION: The SEsl showed promising preclinical results across three models. However, in its present form, it is not suitable for clinical application. TRIAL NUMBER: IRB UMCU 10/154.

Retrograde suction decompression of a large internal carotid aneurysm using a balloon guide catheter combined with a blood-returning circuit and STA-MCA bypass: a technical note.

It is difficult to treat large internal carotid aneurysms with simple surgical clipping. Here, we present a retrograde suction decompression (RSD) procedure for large internal carotid aneurysms using a balloon guide catheter combined with a blood-returning circuit and a superficial temporal artery to middle cerebral artery (STA-MCA) bypass.All patients underwent an STA-MCA bypass before the temporary occlusion of the internal carotid artery (ICA). A 6-French sheath was inserted into the common carotid artery (CCA), and a 6-French Patrive balloon catheter was placed into the ICA 5 cm past the bifurcation. Aneurysm exposure was obtained; temporary clips were placed on the proximal M1, A1, and posterior communicating (Pcom) segments; and an extension tube was then connected to the balloon catheter. A three-way stopcock was placed, and aspiration was performed through the device to collapse the aneurysm. The aspirated blood was returned to a venous line with an added heparin to prevent anemia after aspiration. During the decompression, the blood flow to the cortical area was supplied through the STA-MCA bypass. After the aneurysm collapse, the surgeon carefully dissected the perforating artery from the aneurysm dome or neck, and permanent clips were then placed on the aneurysm neck. Our procedure has several advantages, such as STA-MCA bypass without external carotid artery occlusion for preventing ischemic complications of the cortical area, anemia may be avoided because of the return of the aspirated blood, and a hybrid operation room is not required to perform this method.

Evaluation of occurring complications after flow diverter treatment of elastase-induced aneurysm in rabbits using micro-CT and MRI at 9.4 T.

INTRODUCTION: Flow diverters are increasingly being used to treat intracranial aneurysms. This study evaluates occurring complications of flow-diverting devices in the treatment of experimental aneurysms, involving the use of micro-CT and small animal MRI at 9.4 T, in correlation to angiographic and histological findings. METHODS: We previously published two preclinical studies, in which we assessed two different flow diverters in the treatment of elastase-induced aneurysms. Devices have been implanted across the aneurysm neck as well as in the abdominal aorta. From these studies, a total of 65 devices (prototype FD (n = 30) and Derivo embolization device (n = 35)) additionally underwent micro-CT and MRI after angiographic follow-up and before being histologically examined. RESULTS: The different architectures of both devices were precisely comparable due to high-resolution micro-CT imaging. Micro-CT revealed wire fractures in nine cases (30 %) only with the prototype FD. In three cases (10 %), severe wire fractures correlated with an in-stent stenosis due to intimal hyperplasia. Other complications, like distal stent occlusions and post-stent stenosis, were seen in both groups and verified with both imaging techniques. Osseous metaplasia were correlated to calcifications seen with micro-CT. MRI enabled visualization of the position of the implanted devices relative to the aneurysm and revealed incomplete aneurysm neck coverage with the prototype FD in two cases (6.7 %). CONCLUSION: Micro-CT and 9.4-T MRI are valid to discover and understand occurring complications of flow diverters in the preclinical phase and can serve as evaluation tools to minimize complication rates of endovascular devices in the future.

Anaesthesia for neuroradiology: thrombectomy: 'one small step for man, one giant leap for anaesthesia'.

PURPOSE OF REVIEW: Endovascular management of acute thrombotic strokes is a new management technique. Anaesthesia will play a key role in the management of these patients. To date there is no established method of managing these patients from an anaesthetic perspective. RECENT FINDINGS: In 2015, five landmark studies popularized intra-arterial clot retrieval for ischaemic strokes. Since then there have been a number of small studies investigating the best anaesthetic technique, taking into account patient, technical, and clinical factors. This review summarizes these studies and discusses the different anaesthetic options, with their relative merits and pitfalls. SUMMARY: There is a paucity of robust evidence for the best anaesthetic practice in this cohort of patients. Airway protection seems to be an issue in 2.5% of cases. Timing of the procedure is vital, and any delay may be detrimental to neurological outcome. In a survey of neurointerventionalists, the main concern they expressed was the potential delay to revascularization posed by anaesthesia. Patients complain of pain during mechanical clot retrieval if awake. The overall consensus seems to be favouring conscious sedation over general anaesthesia in the acute setting.

[Application of Silicone Rubber Stents in Intracranial Arterial Microanastomosis for Vessels with Intimal Dissection:A Technical Note].

Intracranial arterial microanastomosis remains an important neurosurgical technique. Intimal dissection of donor or recipient arteries can cause bypass failure. We used a silicone rubber stent while performing arterial microanastomoses, and achieved an excellent postoperative patency rate. In this study, we evaluated the efficacy of the stent in cases of extensive intimal dissection. In 5 cases involving extensive intimal dissection of vessels out of a total of 856 microanastomoses that were performed between November 2000 and August 2014, we placed a silicone rubber stent in the lumen of the recipient artery for donor to recipient suturing. Surgery was performed in 3 cases of cerebrovascular atherosclerotic disease and in 2 cases requiring cerebral revascularization for the treatment of aneurysm recurrence. In one of the 5 cases in which arterial microanastomosis was performed in the spasm period after subarachnoid hemorrhage, a patent anastomosis could not be confirmed. We observed the following advantages of silicone stent use: clear visualization of the orifice created in the vessel, avoidance of suturing or damaging the contralateral side vessel edges, and maintenance of the shape of the anastomosed vessel segment. These advantages made it easier to visualize the intima and to achieve fixation by using tacking sutures.

Evaluation of a newly designed flow diverter for the treatment of intracranial aneurysms in an elastase-induced aneurysm model, in New Zealand white rabbits.

INTRODUCTION: In this study, we analyzed angiographic and histologic aneurysm occlusion of a newly designed flow diverting device. Visibility and flexibility, as well as occlusions of side branches and neointimal proliferation were also evaluated. METHODS: Aneurysms were induced in 18 New Zealand white rabbits and treated with a braided, "closed-loop-designed" device of nitinol. Additional devices were implanted in the abdominal aorta to cover the origin of branch arteries.Angiographic follow-ups were performed immediately after placement of the device, after 3 months (n=9) and 6 months(n =9). The status of aneurysm occlusion (using a five-point scale) and the patency of branch arteries were assessed. RESULTS: Aneurysm occlusion rates were noted as grade 0 in 2 (11 %), grade I in 1 (6 %), grade II in 1 (6 %), grade III in 9(50 %), and grade IV in 5 (28 %) of 18 aneurysms, respectively, indicating a complete or near-complete occlusion of 78 % under double antiplatelet therapy. Aneurysm occlusion was significantly higher at 6 months follow-up (P =0.025). Radiopaque markers provided excellent visibility. Limited device flexibility led to incomplete aneurysm neck coverage and grade 0 occlusion rates in two cases. Distal device occlusions were found in three cases, most likely due to an extremely undersized vessel diameter in the subclavian artery.No case of branch artery occlusion was seen. Intimal proliferation and diameter stenosis were moderate. CONCLUSION: The tested flow diverter achieved near-complete and complete aneurysm occlusion under double antiplatelet therapy of elastase-induced aneurysms in 78 %, while preserving branch arteries.

Delayed ipsilateral parenchymal hemorrhage following treatment of intracranial aneurysms with flow diverter.

INTRODUCTION: The use of flow diverters (FDs) has shown promising results, particularly in the treatment of large or complex intracranial aneurysms. However, some complications can occur both during and after FD treatment, including delayed ipsilateral parenchymal hemorrhage (DIPH). The clinical presentation, etiopathogeny, and management of this complication are not well understood. We report a series of four patients with DIPH and discuss the potential mechanisms and modalities of treatment. METHODS: Four patients treated with FDs and presenting with DIPH were diagnosed in two different centers. Clinical and imaging data were reviewed before and after the procedure. Characteristics of the intraparenchymal hematomas, the modalities of treatment, and clinical course were analyzed. RESULTS: Intraparenchymal hemorrhage occurred 1 to 4 days after aneurysm treatment with FDs. All hemorrhages were situated in the ipsilateral hemisphere and were anatomically remote from the treated aneurysm. The four patients were treated with emergency surgery (hematoma evacuation). All patients had a favorable clinical outcome (mRS = 1) at midterm evaluation. Follow-up imaging showed good permeability of the FD in all subjects and complete aneurysm occlusion in all patients. CONCLUSION: From the literature review, DIPH appears to be more frequent than delayed aneurysm rupture and may be a cause of increasing concern for the use of flow diverters. However, the mechanisms of DIPH are not completely understood. Surgical evacuation of the hematoma seems to be feasible with acceptable safety and good clinical outcomes.

Stability of ischemic core volume during the initial hours of acute large vessel ischemic stroke in a subgroup of mechanically revascularized patients.

INTRODUCTION: This study aimed to relate growth of the infarct core with time to recanalization in patients receiving mechanical recanalization in whom the time of recanalization is known. METHODS: We analyzed data from patients with anterior circulation acute ischemic stroke who underwent mechanical recanalization. Demographic and angiographic characteristics, initial apparent diffusion coefficient (ADC) infarct volume, time-to-peak defect volume, revascularization grade, 24-48 h nonenhanced computed tomography (CT) infarct volume, symptom onset to recanalization time, diffusion-weighted imaging to recanalization time, and discharge National Institutes of Health Stroke Scale (NIHSS) and modified Rankin Scale (mRS) scores were compared between minimal and substantial infarct growth groups. Substantial infarct growth was defined as an increase of infarct volume >10 cm(3) assessed by subtracting initial ADC infarct core volume from infarct volume at 24-48 h CT. RESULTS: Of 25 patients, 9 had minimal infarct growth (median 0 cm(3), interquartile range (IQR) -3 to 5 cm(3)) and 16 had substantial infarct growth (median 103 cm(3), IQR 48-132 cm(3)). Patients with minimal infarct growth had a median time from symptom onset to recanalization of 329 min (IQR 314-412 min) and a median time from imaging to recanalization of 231 min (IQR 198-309 min). On univariate analysis, minimal infarct growth was related to male gender (p = 0.04), smaller initial ADC volume (p = 0.04), higher recanalization grade (p < 0.001), and lower discharge NIHSS (p = 0.04) and mRS grades (p = 0.04). CONCLUSION: There was no or minimal infarct core growth in at least one third of patients despite an exceptionally long median time from magnetic resonance imaging to recanalization of almost 4 h.

[(12)Revascularisation and aneurysms of the posterior circulation].

This is the last article, namely, the twelfth topic, in the series "personal view and historical backgrounds of operative neurosurgery." In this article, revascularisation and aneurysms of the posterior circulation are thematized. As an example for classic posterior circulation EC-IC bypass, a case of basilar stenosis is presented. The stenosis turned out to occlusion by good patency of the STA-SCA bypass, and although it initially showed clinical improvement, it manifested as severe pontine infarction several months later. Considerations on such malignant conversion are discussed together with probable prevention methods. Other revascularisation methods involving the supracerebellar transtentorial approach(SCTTA), namely, OA-SCA or OA-PCA bypass in the sitting position, are presented and their advantages and disadvantages are discussed. As for posterior circulation aneurysms, the role of SEAC and its advantages for treating basilar bifurcation aneurysms are presented and discussed. SCTTA and SAHE approach are presented as special approaches for other PCA aneurysms, and their advantages of getting the parent artery P2 for P2-P3 junction aneurysm in the latter was emphasized. The advantage of a sitting position for revascularisation or aneurysm surgeries, cleanliness of the operative field in cases of premature rupture or clipping procedure, and through the bush of lower cranial nerves are also discussed.

A controlled trial of revascularization in acute stroke.

PURPOSE: To compare safety and utility of intraarterial revascularization with use of stents to no revascularization in patients who either failed to respond to intravenous thrombolysis (IVT) or have contraindications to IVT. MATERIALS AND METHODS: The case-control study was approved by local ethics committees; all patients signed informed consent. One hundred thirty-one patients (74 men; mean age, 65.9 years ± 12.3; range, 25-86 years) with acute ischemic stroke (AIS) due to middle cerebral artery (MCA) occlusion were enrolled; 75 underwent IVT. No further recanalization therapy was performed in 26 (35%) IVT-treated patients with MCA recanalization (group 1). Patients with IVT failure after 60 minutes were allocated to endovascular treatment (group 2A) or no further therapy (group 2B). Patients with contraindication to IVT were allocated to endovascular treatment within 8 hours since AIS onset (group 3A) or to no recanalization therapy (group 3B). Neurologic deficit at admission, MCA recanalization, symptomatic intracerebral hemorrhage (SICH), and 3-month clinical outcome were evaluated. Favorable clinical outcome was defined as modified Rankin scale score 0-2 at 3 months after stroke onset. Two-sided Mann-Whitney U test, independent samples t test, Fisher exact test, multivariate logistic regression analysis of baseline variables, and complete MCA recanalization for the prediction of favorable clinical outcome were used for statistical evaluation. RESULTS: Median National Institutes of Health Stroke Scale score at admission was 13.5, 16.0, 15.5, 15.0, and 16.0 in groups 1, 2A, 2B, 3A, and 3B, respectively (P > .05); SICH occurred in one of 26 (3.8%), one of 23 (4.3%), one of 26 (3.8%), one of 31 (3.2%), and one of 25 (4.0%) patients, respectively (P > .05). MCA recanalization after endovascular treatment was achieved in 50 of 54 (92.6%) patients. Favorable outcome was significantly different between groups 2A and 2B (10 of 23 [43.5%] and four of 26 [15.4%], respectively; P = .03) and groups 3A and 3B (14 of 31 [45.2%] and two of 25 [8.0%], respectively; P = .004) and was dependent on MCA recanalization (odds ratio, 5.55; P = .006). CONCLUSION: In this controlled trial, intraarterial revascularization with stents was an effective and safe-effective treatment option in patients with acute MCA occlusion with contraindication to IVT or after IVT failure.