Cerebral Revascularization Surgery Research Articles

Indications for cerebral revascularization for moyamoya syndrome in pediatric sickle cell disease determined by Delphi methodology.

Cerebral revascularization surgery (CRS) has been used to prevent stroke in children with sickle cell disease (SCD) and cerebral vasculopathy (e.g., moyamoya syndrome). While results suggest that it may be an effective treatment, surgical indications have not been well defined. This study sought to determine indications for offering revascularization surgery in centers with established sickle cell programs in the US. Three sequential surveys utilizing the Delphi methodology were administered to neurosurgeons participating in the Stroke in Sickle Cell Revascularization Surgery study. Respondents were presented with clinical scenarios of patients with SCD and varying degrees of ischemic presentation and vasculopathy, and the group's agreement to offer surgical revascularization was measured. Consensus was defined as ≥ 75% similar responses. The response rate to all 3 surveys was 100%. Seventeen neurosurgeons from 16 different centers participated. The presence of moyamoya collaterals (MMCs) and arterial stenosis matching an ischemic distribution yielded the strongest recommendations to offer surgery. There was consensus to offer revascularization in the presence of MMCs and at least 50% arterial stenosis matching an ischemic distribution. In contrast, there was no consensus to offer revascularization with 50%-70% stenosis not matching an ischemic presentation in the absence of MMCs. The presence of the ivy sign in the distribution of the stenotic artery also contributed to the consensus to offer surgery in certain scenarios. There were several clinical scenarios that attained consensus to offer surgery; the strongest was moderate to severe arterial stenosis that matched the distribution of ischemic presentation in the presence of MMCs. Radiological findings of decreased cerebral flow or perfusion also facilitated attaining consensus to offer surgery. The findings of this study reflect expert opinion about questions that deserve prospective clinical research. Determination of indications for CRS can guide clinical practice and aid the design of prospective studies.

Impact of Cerebral Revascularization on Pial Collateral Flow in Patients With Unilateral Moyamoya Disease Using Quantitative Magnetic Resonance Angiography.

Moyamoya disease (MMD) is a chronic steno-occlusive disease of the intracranial circulation that depends on neoangiogenesis of collateral vessels to maintain cerebral perfusion and is primarily managed with cerebral revascularization surgery. A quantitative assessment of preoperative and postoperative collateral flow using quantitative magnetic resonance angiography with noninvasive optimal vessel analysis (NOVA) was used to illustrate the impact of revascularization on cerebral flow distribution. A retrospective review of patients with unilateral MMD who underwent direct, indirect, or combined direct/indirect cerebral revascularization surgery was conducted between 2011 and 2020. Using NOVA, flow was measured at the anterior cerebral artery (ACA), ACA distal to the anterior communicating artery (A2), middle cerebral artery (MCA), posterior cerebral artery (PCA), and PCA distal to the posterior communicating artery (P2). Pial flow (A2 + P2) and collateral flow (ipsilateral [A2 + P2])-(contralateral [A2 + P2]) were measured and compared before and after revascularization surgery. Total hemispheric flow (MCA + A2 + P2) with the addition of the bypass graft flow postoperatively was likewise measured. Thirty-four patients with unilateral MMD underwent cerebral revascularization. Median collateral flow significantly decreased from 68 to 39.5 mL/min (P = .007) after bypass. Hemispheres with maintained measurable bypass signal on postoperative NOVA demonstrated significant reduction in median collateral flow after bypass (P = .002). Median total hemispheric flow significantly increased from 227 mL/min to 247 mL/min (P = .007) after bypass. Only one patient suffered an ipsilateral ischemic stroke, and no patients suffered a hemorrhage during follow-up. NOVA measurements demonstrate a reduction in pial collateral flow and an increase in total hemispheric flow after bypass for MMD, likely representing a decrease in leptomeningeal collateral stress on the distal ACA and PCA territories. Further studies with these measures in larger cohorts may elucidate a role for NOVA in predicting the risk of ischemic and hemorrhagic events in MMD.

Troubleshooting the bypass: intraoperative management of initially failed anastomosis in direct cerebral revascularization surgery.

Direct cerebral revascularization is considered as one of the most technically challenging operations in neurosurgery. Technical errors are often not identified during the case, but only after the recirculation stage, making management crucial at that time of the procedure. In this study, the authors sought to describe troubleshooting of the technical errors encountered in initially failed bypass cases. A retrospective analysis describing a single-surgeon, single-institution experience between 2014 and 2021 was performed, based on operative reports and videos, including a 30-day follow-up period. Initially failed bypass was defined if the bypass was not patent or had a significant leak after recirculation, irrespective of the final result. One hundred thirty-eight bypass cases were reviewed for complex aneurysms (n = 49), moyamoya disease (n = 59), and atherosclerosis (n = 30). Fifty-one initially failed anastomoses were identified; 43 of these were the result of a technical error. Etiologies of these failed anastomoses included a clot (n = 14), vessel kinking (n = 4), spasm (n = 5), suture-related cause (n = 5), inappropriate donor or recipient (n = 3), or lack of demand (n = 8). A major leak was attributed to an uncoagulated side branch (n = 4), vessel injury due to suture/clip placement (n = 1), or inadequate suture line coverage (n = 7). Thirty-seven (86%) of 43 cases were troubleshot successfully, as salvage maneuvers included papaverine vessel massage, donor repositioning, re-anastomosis for occlusion in select cases, local hemostatic agents, and suturing or coagulating side branches in a leak. Thirty-day follow-up revealed similar rates of patency between successfully troubleshot patients (35/37) and the rest of the cases (80/87, p = 0.6). Three major patterns of a noncompatible bypass were found: a major leak, an acute occlusion, or a delayed occlusion. Based on the authors' experience, salvage strategies proved successful, showing an eventual high patency rate. The authors suggest a gradual, structured algorithm to address this stage in surgery that may contribute specifically to cerebrovascular neurosurgeons at the beginning of their careers.

Electrospun Polyurethane Vascular Grafts for Cerebral Revascularization: A Pilot Study on Rats

The current standard technique for vascular grafting in cerebral revascularization surgery employs the interposition of an autologous blood vessel. Technical complications have necessitated the development of a synthetic alternative, but classical biomaterials are not suited for small caliber vascular grafting due to the resulting neointimal hyperplasia and thrombosis. The electrospinning of polymers is a promising technique for the development of small vascular grafts. The in vivo performance and efficacy of electrospun polyurethane (ePU) grafts with an internal diameter of <1.5 mm have thus far not been evaluated. We developed a novel ePU graft, with a diameter of 1.25 mm, for implantation into the infrarenal aorta of rats. The patency rates of grafts after a 4-month period were equal to those reported in other studies using larger ePU graft diameters and equal or higher than in studies employing other biomaterials. We observed some loss in flow velocity throughout the grafts, which suggests a decreased elasticity of the graft compared to that of the native rat aorta. However, the grafts demonstrated good neo-endothelialization and minimal neointimal hyperplasia. Their porosity promoted cellular infiltration, as observed under tissue slide examination. Our results show that ePU vascular grafts with an internal diameter of <1.5 mm are promising candidates for vascular grafting in cerebral revascularization surgery.

Arterial spin labeling for moyamoya angiopathy: A preoperative and postoperative evaluation method.

Studies have shown that arterial spin labeling (ASL) effectively replaces traditional MRI perfusion imaging for detecting cerebral blood flow (CBF) in patients with Moyamoya angiopathy (MMA). However, there are few reports on the relationship between neovascularization and cerebral perfusion in patients with MMA. The aim of this study is to investigate the effects of neovascularization on cerebral perfusion with MMA after bypass surgery. We selected patients with MMA in the Department of Neurosurgery between September 2019 and August 2021 and enrolled them based on the inclusion and exclusion criteria. ASL imaging was used to monitor the baseline CBF level before surgery and determine the changes in cerebral vessels at postoperative 1 week and 6 months, respectively. The Alberta stroke grade, modified Rankin Scale (mRS), and digital subtraction angiography images were used to evaluate the effect of postoperative CBF status and prognosis. Ninety hemispheres from 51 patients were included in this study. There were no significant differences in the baseline data of the enrolled patients. At 1 week and 6 months post-surgery, the CBF state in the operation area was significantly changed compared with that at baseline (P < 0.05). The preoperative Alberta score (t = 2.714, P = 0.013) and preoperative mRS score (t = 6.678, P < 0.001) correlated with postoperative neovascularization. ASL is an effective method for detecting CBF and plays an important role in the long-term follow-up of patients with MMA. Combined cerebral revascularization significantly improves CBF in the operation area both in the short and long terms. Patients with lower preoperative Alberta scores and higher mRS scores were more likely to benefit from combined cerebral revascularization surgery. However, regardless of the type of patient, CBF reconstruction can effectively improve prognosis.

Highlight: Is smoke the signal for surgery? Should the moyamoya syndrome "puff of smoke" trigger cerebral revascularization surgery in children with sickle cell disease?

The authors declare they have no relevant conflicts of interest.

Cerebral revascularization surgery reduces cerebrovascular events in children with sickle cell disease and moyamoya syndrome: Results of the stroke in sickle cell revascularization surgery retrospective study.

Recent studies suggest that cerebral revascularization surgery may be a safe and effective therapy to reduce stroke risk in patients with sickle cell disease and moyamoya syndrome (SCD-MMS). We performed a multicenter, retrospective study of children with SCD-MMS treated with conservative management alone (conservative group)-chronic blood transfusion and/or hydroxyurea-versus conservative management plus surgical revascularization (surgery group). We monitored cerebrovascular event (CVE) rates-a composite of strokes and transient ischemic attacks. Multivariable logistic regression was used to compare CVE occurrence and multivariable Poisson regression was used to compare incidence rates between groups. Covariates in multivariable models included age at treatment start, age at moyamoya diagnosis, antiplatelet use, CVE history, and the risk period length. We identified 141 patients with SCD-MMS, 78 (55.3%) in the surgery group and 63 (44.7%) in the conservative group. Compared with the conservative group, preoperatively the surgery group had a younger age at moyamoya diagnosis, worse baseline modified Rankin scale scores, and increased prevalence of CVEs. Despite more severe pretreatment disease, the surgery group had reduced odds of new CVEs after surgery (odds ratio=0.27, 95% confidence interval [CI]=0.08-0.94, p=.040). Furthermore, comparing surgery group patients during presurgical versus postsurgical periods, CVEs odds were significantly reduced after surgery (odds ratio=0.22, 95% CI=0.08-0.58, p=.002). When added to conservative management, cerebral revascularization surgery appears to reduce the risk of CVEs in patients with SCD-MMS. A prospective study will be needed to validate these findings.

Application of intraoperative infrared thermography in bypass surgery for adult moyamoya syndrome: A preliminary study.

Cerebral revascularization surgery is the mainstay of treatment for moyamoya syndrome (MMS) today, and intraoperative determination of the patency of the revascularized vessel is a critical factor in the success of the procedure. Currently, major imaging modalities include intraoperative indocyanine green (ICG) videoangiography (ICG-VA), digital subtraction angiography (DSA), and vascular ultrasound Doppler. Infrared thermography is a modern imaging modality with non-contact devices for the acquisition and analysis of thermal data. We aimed to investigate the feasibility and advantages of infrared thermography in determining anastomotic patency during MMS surgery. Indocyanine green videoangiography and infrared thermography were performed simultaneously in 21 patients with MMS who underwent bypass surgery. The detection result of vessel patency was compared, and the feasibility and advantages of infrared thermography were assessed. The patency of the anastomosis was accurately determined in 21 patients using either ICG angiography or infrared thermography. In 20 patients, the results of infrared thermography showed that the vascular anastomosis was unobstructed, and there was an agreement with the subsequent results of ICG-VA. In one patient, we suspected inadequate patency after testing the anastomosis with infrared thermography, and the results of ICG-VA evaluation of the anastomosis confirmed that there was indeed an anastomotic obstruction. Compared with ICG-VA, infrared thermography might offer an alternative non-invasive, contrast-free option in assessing anastomosis patency compared with ICG-VA, and it is likely to become more widely used in the clinic in the near future.

The changing landscape of cerebral revascularization surgery: A United Kingdom experience.

We describe the chronological trends in cerebral revascularization surgery through a single-surgeon experience; and we review whether in the context of giant and fusiform cerebral aneurysms, flow-diverting stents have impacted on the use of cerebral revascularization surgery. We review our single institution prospectively collected database of cerebral revascularization procedures between 2006 and 2018. Comparing this to our database of flow-diverting endovascular stent procedures, we compare the treatment of fusiform and giant aneurysms. We describe patient demographics, procedural incidence, complications, and outcomes. Between 2006 and 2018, 50 cerebral revascularization procedures were performed. The incidence of cerebral revascularization surgery is declining. In the context of giant/fusiform aneurysm treatment, the decline in cerebral revascularization is accompanied by a rise in the use of flow-diverting endovascular stents. Thirty cerebral revascularizations were performed for moyamoya disease and 11 for giant/fusiform aneurysm. Four (14%) direct bypass grafts occluded without neurological sequela. Other morbidity included hydrocephalus (2%), transient ischemic attacks (2%), and ischemic stroke (2%). There was one procedure-related mortality (2%). Flow-diverting stents were inserted for seven fusiform and seven giant aneurysms. Comparing the treatment of giant/fusiform aneurysms, there was no significant difference in morbidity and mortality between cerebral revascularization and flow-diverting endovascular stents. We conclude that with the decline in the incidence of cerebral revascularization surgery, there is a need for centralization of services to allow high standards and outcomes to be maintained.

The Role of Early Superficial Temporal to Middle Cerebral Artery Bypass Revascularization Surgery in Middle Cerebral Artery‐Territory Strokes: A Systematic Review Study

Background To systematically summarize and critically review the available literature regarding the functional outcome of the urgent superficial temporal artery to the middle cerebral artery (MCA) bypass surgery in stroke patients associated with MCA lesions. Methods The current systematic review was conducted and reported using the Preferred Reporting Items for Systematic Reviews and Meta‐Analysis statement. Medline (PubMed), ISI Web of Science, Scopus, and google scholar (manually searches) were systematically searched up to August 2021. The eligibility criteria were defined as all the patients who had MCA‐territory strokes due to MCA/intradural internal carotid artery lesions that underwent same‐admission superficial temporal artery‐MCA bypass surgery. The strokes with cervical internal carotid artery and anterior cerebral artery lesions/strokes were excluded. The checklists produced by the US National Heart Lung and Blood Institute were used for quality assessment. Demographic variables, clinical findings, National Institutes of Health Stroke Scale scores, the time interval between symptoms to surgery, imaging results, endovascular treatments, surgical notes, mortality rate, follow‐up findings, modified Rankin scale scores, and all reported medical records were extracted and analyzed with SPSS software (ver. 23). P values ≤0.05 were considered meaningful. Results The initial search yielded 3050 records, and 13 articles met the inclusion criteria and entered this systematic review. A total of 165 patients were pooled for data analysis. Nine studies had data regarding neurological deficits before and after surgery. Except for 5 patients, the National Institutes of Health Stroke Scale score after the operation was the same or better than the preoperative score. Eleven out of 17 patients in 3 studies showed early neurological improvement (a decrease in National Institutes of Health Stroke Scale score of ≥4 points at 3 days) after bypass surgery. Functional outcome was stated in 10 studies. Overall, a good functional outcome (modified Rankin scale=0–2) was achieved in 9 out of 21 (42.1%) patients at discharge and in 44 out of 59 (74.5%) patients at 3 months follow‐up. Lower age was associated with favorable outcomes. Long‐term graft patency was excellent in 99.5% of patients. Postoperative hematoma and mortality (all noncranial) rates were 3% and 3.6%, respectively. Conclusion The current study suggests that early superficial temporal artery‐MCA revascularization should be considered an available option in younger patients (&lt;60‐year‐old) with MCA territory strokes who fail medical treatment.

Cerebral Bypass Using the Descending Branch of the Lateral Circumflex Femoral Artery: A Case Series.

When performing extracranial to intracranial (EC-IC) and intracranial to intracranial (IC-IC) bypass, the choice of donor vessel and interposition graft depends on several factors: vessel size and accessibility, desired blood flow augmentation, revascularization site anatomy, and pathology. The descending branch of the lateral circumflex femoral artery (DLCFA) is an attractive conduit for cerebrovascular bypass. To present our institutional experience using DLCFA grafts for cerebral revascularization. Retrospective review of perioperative data and outcomes for patients undergoing cerebrovascular bypass surgery using a DLCFA graft from 2016 to 2019. Twenty consecutive patients underwent EC-IC bypass using a DLCFA interposition graft. Bypass indications included 13 (65%) intracranial aneurysms, 4 (20%) medically refractory atherosclerotic large artery occlusions (internal carotid artery or middle cerebral artery), 2 (10%) internal carotid artery dissections, and 1 (5%) patient with moyamoya disease. Most commonly, a donor superior temporal artery was bypassed to a recipient middle cerebral artery (14 of 20; 70%). Two cases demonstrated graft spasm. Graft occlusion occurred in one patient and was asymptomatic. Perioperative bypass surgery-related ischemia occurred in 3 patients: 1 patient with insufficient bypass flow, 1 patient with graft stenosis because of an adventitial band, and 1 patient with focal status epilepticus in the bypassed territory resulting in cortical ischemia. One donor site hematoma occurred. The median (range) modified Rankin scale (mRS) score on follow-up was 1.5 (1-4) at 7.8 (1-27) months, with most patients achieving good functional outcomes (mRS ≤2). The DLCFA is a versatile graft for cerebral revascularization surgery, demonstrating good outcomes with minimal graft harvest site morbidity and an acceptable graft patency rate.

Anesthetic Management of Moyamoya Syndrome Secondary to Sickle Cell Anemia

AbstractMoyamoya disease (MMD) is caused by stenosis or occlusion of internal carotid artery in brain, thereby reducing its blood supply. To augment blood flow, brain develops abnormal anastomotic vessels with deranged carbon dioxide reactivity and tendency to bleed. Moyamoya syndrome (MMS) is the name given to MMD when the latter results from secondary to some associated disease. Occurrence of MMS secondary to sickle cell anemia (SCA) presents unique challenges to neuroanesthesiologists. Management of various physiological parameters for cerebral revascularization surgery for MMD under general anesthesia necessitates vigilant and balanced control of various physiological variables, as the manipulation of a particular physiological variable for one pathology may adversely impact the same physiological variable for the associated disease, which will result in poor outcome of the patient. Therefore, optimum outcome of MMS is determined by a watchful balancing of various physiological parameters under anesthesia.

Long-term clinical and radiographic outcomes after pial pericranial dural revascularization: a hybrid surgical technique for treatment of anterior cerebral territory ischemia in pediatric moyamoya disease.

Isolated anterior cerebral artery (ACA) territory ischemia in pediatric moyamoya disease (MMD) is rare but has been increasingly recognized, particularly in children manifesting progression of disease in a delayed fashion after middle cerebral artery revascularization surgery. Surgical treatment is complicated by limited graft choices, with the small number of case series largely focused on complex, higher-risk operations (omental flap transfers, large interhemispheric rotational grafts); direct bypass (often untenable in children due to vessel size); or, alternatively, the technically simpler method of multiple burr holes (of limited efficacy outside of infants). Faced with the problem of a growing cohort of pediatric patients with MMD that could benefit from anterior cerebral revascularization, the authors sought to develop a solution that was specifically designed for children and that would be lower risk than the more complex approaches adapted from adult populations but more effective than simple burr holes. In this study, the authors aimed to describe the long-term clinical and radiographic outcomes of a novel approach of pial pericranial dural (PiPeD) revascularization, building on the principles of pial synangiosis but unique in using the pericranium and the dura mater as the primary vascular supply, and employing a larger craniotomy with arachnoid dissection to provide robust full-territory revascularization in all ages with reduced risk relative to more complex procedures. The medical records of all pediatric patients with MMD who presented at a single center between July 2009 and August 2019 were retrospectively reviewed to identify patients with MMD with anterior cerebral territory ischemia. Clinical characteristics, surgical indications, operative techniques, and long-term clinical and radiographic follow-up data were collected and analyzed. A total of 25 operations (5.6% of total procedures) were performed in 21 patients (mean age 9.4 years [range 1-16.5 years]; 12 female and 9 male). Almost one-third of the patients had syndromic associations, with no familial cases. Complications included 1 patient (4.7%) with a superficial infection, with no postoperative strokes, hemorrhage, seizures, or deaths. Long-term follow-up was available in 18 of 21 patients (mean 24.9 months [range 4-60 months]). Radiographic engraftment was present in 90.9% (20/22 hemispheres), and no new strokes were evident on MRI on long-term follow-up, despite radiographic progression of the disease. The use of the pericranium and the dura mater for indirect revascularization provided robust vascularized graft with great flexibility in location and high potential for engraftment, which may obviate more complex and higher-risk operations for ACA territory ischemia. Long-term follow-up demonstrated that PiPeD revascularization conferred durable, long-term radiographic and clinical protection from stroke in pediatric patients with MMD. Based on the results of the current study, the PiPeD technique can be considered an additional tool to the armamentarium of indirect revascularization procedures in select pediatric patients with MMD.

Clinical Implications of the “Brush Sign” in Susceptibility-Weighted Imaging for Moyamoya Disease

Objective: Infarction is one of the most common postoperative complications after surgical revascularization for moyamoya disease (MMD). Increased conspicuity of deep medullary veins (DMVs) on susceptibility-weighted imaging (SWI), known as “brush sign,” could predict the severity of MMD. This study aimed to reveal the features of the “brush sign” in preoperative SWI and to verify its relationship to postoperative infarction. Methods: Consecutive patients with MMD who had undergone cerebral revascularization surgery were included. Routine preoperative SWI was performed. The “brush sign” was defined according to the number of the conspicuous DMVs > 5 detected on SWI. Postoperative infarctions were defined as the high-intensity signal on postoperative DWI images, with or without neurologic deficits. The modified Rankin scale (mRS) was applied to evaluate the prognosis of patients. Results: In the enrolled 100 hemispheres, 35 were presented with the “brush sign.” Patients with ischemic onset manifestation and previous infarction history tended to present with the “brush sign.” Multivariate analysis showed that the “brush sign” (OR 13.669; 95% CI, 1.747–106.967, p = 0.013) and decreased rCBF (OR 6.050; 95% CI, 1.052–34.799, p = 0.044) were independent risk factors of postoperative infarction. Besides, the “brush sign” showed a significant correlation with a higher mRS score at discharge (p = 0.047). Conclusion: The findings strongly suggest that the presence of the “brush sign” preoperatively can be a predictor of infarction after surgical revascularization for ischemic MMD. It may contribute to an improved surgical result through focused perioperative management based on appropriate surgical risk stratification.

Vessel territory mapping after cerebral revascularization surgery using selective angiographic flat detector perfusion imaging.

The technical feasibility and diagnostic potential of angiographic flat-detector perfusion imaging technique, combining digital subtraction angiography with a flat-detector computed tomography steady-state perfusion imaging, was explored in patients treated with direct or indirect revascularization surgery. This short communication is about an imaging modality with great potential for evaluation, comparison and grading of vascular perfusion territory areas and anatomical location selectively perfused by direct and indirect cerebral bypasses.

Complications of cerebral revascularization surgery

Complications of cerebral revascularization surgery

Letter to the Editor. Graft selection in cerebral revascularization surgery.

Letter to the Editor. Graft selection in cerebral revascularization surgery.

Microsurgical Techniques for Exposing the Internal Maxillary Artery in Cerebral Revascularization Surgery: A Comparative Cadaver Study

The internal maxillary artery (IMAX) is currently considered one of the main donor vessels in extracranial-to-intracranial bypass surgeries. Four main techniques for harvesting the IMAX have been described: via the anterior medial infratemporal fossa (AMITF), the middle infratemporal fossa (MITF), the anterior lateral middle fossa (ALMF), and the lateral middle fossa (LMF). The advantages and limitations of these techniques have not yet been systematically evaluated and compared. Twenty-five cadaver specimens were used to evaluate the harvesting technique. The length and the caliber of the targeted IMAX segments, as well as the depth from the operating plane to the IMAX, surgical time, and surgical area of exposure, were analyzed. The MITF technique provided the greatest operating area of exposure (mean, 3.88 ± 0.97 cm2). The LMF and MITF techniques provided the largest IMAX caliber (mean, 3.1 ± 0.4 mm and 3.0 ± 0.3 mm, respectively). The ALMF technique provided the shallowest operative depth as well as the least time of exposure (21.8 minutes). The MITF technique exposed the longest IMAX segment (mean, 18.8 ± 3.5 mm). Advantages of the AMITF and MITF techniques include anatomic simplicity, absence of skull base drilling, and greater discretion in muscle dissection. These properties can simplify the anastomosis procedure compared with the ALMF and LMF techniques. Identification of the IMAX pattern is important before selecting the approach for this bypass operation.

Surgical Designs of Revascularization for Moyamoya Disease: 15 Years of Experience in a Single Center

Cerebral revascularization surgery has been established as an effective treatment for moyamoya disease. On the other hand, harvesting grafts and tissues to nourish the scalp may increase the risk of postoperative wound-related complications. The purpose of this study was to clarify risk factors for wound-related complications after examining the relationship with the surgical design. We retrospectively analyzed 115 patients who underwent 197 revascularization procedures between October 2004 and March 2019. The design of the revascularization was classified into 6 types, then further classified according to the number of grafts harvested, resulting in 11 subtypes. Incidences of minor and major wound-related complications for the 11 different surgical designs were assessed. The risk of complications from each design was statistically examined. In addition, the yearly transition rate of complications was also investigated. Wound-related complications occurred in 38 of the 195 operations (19.5%), including 10 major events (26.3%) and 28 minor events (73.7%). Significant differences in the incidence of complications were seen according to surgical design (P < 0.05), with complications significantly more frequent for L(a) double type and L(p) double type and less frequent for L(a) single type and L(p) single type. In addition, significant differences were found in the incidence and degree of complications according to the number of grafts (0-2) (P < 0.05). The incidence of wound-related complications has clearly decreased since2015. Wound-related complications were more frequent and tended to become more severe with double-bypass procedures but were clearly improved under a plastic surgery approach.

Revascularization surgery for symptomatic non-moyamoya intracranial arterial stenosis or occlusion.

Previous trials rejected a role of extracranial-to-intracranial bypass surgery for managing symptomatic atheromatous disease. However, hemodynamic insufficiency may still be a rationale for surgery, provided the bypass can be performed with low morbidity and patency is robust. Consecutive patients undergoing bypass surgery for symptomatic non-moyamoya intracranial arterial stenosis or occlusion were retrospectively identified. The clinical course and surgical outcomes of the cohort were evaluated at 6 weeks, 6 months, and annually thereafter. From 1992 to 2017, 112 patients underwent 127 bypasses. The angiographic abnormality was arterial occlusion in 80% and stenosis in 20%. Procedures were performed to prevent future stroke (76%) and stroke reversal (24%), with revascularization using an arterial pedicle graft in 80% and venous interposition graft (VIG) in 20%. A poor outcome (bypass occlusion, new stroke, new neurological deficit, or worsening neurological deficit) occurred in 8.9% of patients, with arterial pedicle grafts (odds ratio [OR] 0.15), bypass for prophylaxis against future stroke (OR 0.11), or anterior circulation bypass (OR 0.17) identified as protective factors. Over the first 8 years following surgery the 66 cases exhibiting all three of these characteristics had minimal risk of a poor outcome (95% confidence interval 0%-6.6%). Prophylactic arterial pedicle bypass surgery for anterior circulation ischemia is associated with high graft patency and low stroke and surgical complication rates. Higher risks are associated with acute procedures, typically for posterior circulation pathology and requiring VIGs. A carefully selected subgroup of individuals with hemodynamic insufficiency and ischemic symptoms is likely to benefit from cerebral revascularization surgery.