Assessing superficial temporal artery-middle cerebral artery anastomosis patency using FLOW 800 hemodynamics.

OBJECTIVE: The objective of this study was to investigate the use of indocyanine green videoangiography with FLOW 800 hemodynamic parameters intraoperatively during superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery to predict patency prior to anastomosis performance. METHODS: A retrospective and exploratory data analysis was conducted using FLOW 800 software prior to anastomosis to assess four regions of interest (ROIs; proximal and distal recipients and adjacent and remote gyri) for four hemodynamic parameters (speed, delay, rise time, and time to peak). Medical records were used to classify patients into flow and no-flow groups based on immediate or perioperative anastomosis patency. Hemodynamic parameters were compared using univariate and multivariate analyses. Principal component analysis was used to identify high risk of no flow (HRnf) and low risk of no flow (LRnf) groups, correlated with prospective angiographic follow-ups. Machine learning models were fitted to predict patency using FLOW 800 features, and the a posteriori effect of complication risk of those features was computed. RESULTS: A total of 39 cases underwent STA-MCA bypass surgery with complete FLOW 800 data collection. Thirty-five cases demonstrated flow after anastomosis revascularization and were compared with 4 cases with no flow after revascularization. Proximal and distal recipient speeds were significantly different between the no-flow and flow groups (proximal: 238.3 ± 120.8 and 138.5 ± 93.6, respectively [p < 0.001]; distal: 241.0 ± 117.0 and 142.1 ± 103.8, respectively [p < 0.05]). Based on principal component analysis, the HRnf group (n = 10) was characterized by high-flow speed (> 75th percentile) in all ROIs, whereas the LRnf group (n = 10) had contrasting patterns. In prospective long-term follow-up, 6 of 9 cases in the HRnf group, including the original no-flow cases, had no or low flow, whereas 8 of 8 cases in the LRnf group maintained robust flow. Machine learning models predicted patency failure with a mean F1 score of 0.930 and consistently relied on proximal recipient speed as the most important feature. Computation of posterior likelihood showed a 95.29% chance of patients having long-term patency given a lower proximal speed. CONCLUSIONS: These results suggest that a high proximal speed measured in the recipient vessel prior to anastomosis can elevate the risk of perioperative no flow and long-term reduction of flow. With an increased dataset size, continued FLOW 800-based ROI metric analysis could be used to guide intraoperative anastomosis site selection prior to anastomosis and predict patency outcome.

Functional ultrasound imaging of human brain activity through an acoustically transparent cranial window.

Visualization of human brain activity is crucial for understanding normal and aberrant brain function. Currently available neural activity recording methods are highly invasive, have low sensitivity, and cannot be conducted outside of an operating room. Functional ultrasound imaging (fUSI) is an emerging technique that offers sensitive, large-scale, high-resolution neural imaging; however, fUSI cannot be performed through the adult human skull. Here, we used a polymeric skull replacement material to create an acoustic window compatible with fUSI to monitor adult human brain activity in a single individual. Using an in vitro cerebrovascular phantom to mimic brain vasculature and an in vivo rodent cranial defect model, first, we evaluated the fUSI signal intensity and signal-to-noise ratio through polymethyl methacrylate (PMMA) cranial implants of different thicknesses or a titanium mesh implant. We found that rat brain neural activity could be recorded with high sensitivity through a PMMA implant using a dedicated fUSI pulse sequence. We then designed a custom ultrasound-transparent cranial window implant for an adult patient undergoing reconstructive skull surgery after traumatic brain injury. We showed that fUSI could record brain activity in an awake human outside of the operating room. In a video game "connect the dots" task, we demonstrated mapping and decoding of task-modulated cortical activity in this individual. In a guitar-strumming task, we mapped additional task-specific cortical responses. Our proof-of-principle study shows that fUSI can be used as a high-resolution (200 µm) functional imaging modality for measuring adult human brain activity through an acoustically transparent cranial window.

Open Surgical Treatment of Middle Cerebral Artery Aneurysms: A Single-Center Series in the Endovascular Era.

OBJECTIVE: We review the outcomes of open surgical treatment of middle cerebral artery aneurysms (MCAAs) at a single center, focusing on aneurysm obliteration rates and functional outcomes at the most recent follow-up. These findings can be used for future comparisons of surgical outcomes with MCAAs. METHODS: We retrospectively reviewed cases from a prospectively maintained database of patients receiving open surgical treatment for ruptured or unruptured MCAAs between July 2014 and December 2022. We utilized patients' modified Rankin Scale (mRS) score and Glasgow Outcome Scale score as functional outcome measures. Means, standard deviations, medians, and interquartile ranges were calculated, and a student's t test or its nonparametric equivalent was used to compare subgroups. RESULTS: One hundred fifty patients (114 women, 76%; mean age 55.0 ± 14.7 years) with a total of 156 MCAAs comprised 152 cases; 85 (56%) ruptured and 71 (46%) unruptured. Bypass was performed in 34 cases (22.4%); 18 ruptured (51.4%) and 16 unruptured (48.6%). Intraoperative rupture occurred in 5 (5%) ruptured and 1 (2%) unruptured cases. Onwe hundred forty-five patients (95.4%) had aneurysm obliteration with initial surgery, with 98.4% of patients having complete occlusion at 40.2± 65.5 weeks of follow-up. Intrahospital mortality occurred in 7 (6.9%) ruptured versus 1 (2.0%) unruptured case. Fifty-two (51.5%) of the ruptured compared to 43 (86%) unruptured patients were discharged home, with the remaining patients requiring inpatient rehabilitation or long-term hospitalization. The ruptured group had a mean hospital stay of 18.4 ± 10.5 days versus. 5.7 ± 6.0 days for unruptured. Length of stay, discharge mRS/ Glasgow Outcome Scale, and mRS at 4-6 weeks favored unruptured cases (P < 0.0001-0.0336). Mean change in mRS from presentation to last follow-up favored ruptured cases (-0.7 ± 1.2 vs. -0.04 ± 1.2, P = 0.0215). CONCLUSIONS: Open surgery remains a safe and definitive treatment option for MCAAs in the endovascular era.

Neurotropism of SARS-CoV-2: A Pathological Examination of Neurosurgical Specimens.

BACKGROUND AND OBJECTIVES: Neurological manifestations may occur in more than 80% of patients hospitalized with COVID-19 infection, including severe disruptions of the central nervous system (CNS), such as strokes, encephalitis, or seizures. Although the primary pathophysiological mechanism for the effects of COVID-19 in CNS remains unknown, evidence exists for both direct injury from neuroinvasion and indirect effects from disruptions in systemic inflammatory and coagulation pathways. In this study, we analyzed CNS tissue from living patients to better understand these processes. METHODS: With institutional review board approval and patient consent, samples that would be otherwise discarded from patients with active or recent (within 6 days of surgery) COVID-19 infection undergoing neurosurgical intervention were collected and tested for the presence of SARS-CoV-2 using immunohistochemistry, in situ hybridization, electron microscopy, and reverse transcription polymerase chain reaction. RESULTS: Five patients with perioperative mild-to-moderate COVID-19 infection met inclusion criteria (2 male, 3 female; mean age 38.8 ± 13.5 years). Neurosurgical diagnoses included a glioblastoma, a ruptured arteriovenous malformation, a ruptured posterior inferior cerebellar artery aneurysm, a middle cerebral artery occlusion, and a hemorrhagic pontine cavernous malformation. Samples analyzed included the frontal lobe cortex, olfactory nerve, arteriovenous malformation/temporal lobe parenchyma, middle cerebral artery, cerebellum, and cavernous malformation/brainstem parenchyma. Testing for the presence of SARS-CoV-2 was negative in all samples. CONCLUSION: The CNS is likely not a significant viral reservoir during mild-to-moderate COVID-19 infection, although direct neuroinvasion is not definitively excluded. Additional testing to help elucidate the relative contributions of direct and indirect pathways for CNS injury from COVID is warranted.

Three-Vessel Anastomosis for Direct Multiterritory Cerebral Revascularization: Case Series.

BACKGROUND AND OBJECTIVE: Cerebral revascularization of multiple territories traditionally requires multiple constructs, serial anastomoses, or a combination of direct and indirect approaches. A novel 3-vessel anastomosis technique allows for direct, simultaneous multiterritory cerebral revascularization using a single interposition graft. We herein present our experience with this approach. METHODS: Retrospective review of perioperative data and outcomes for patients undergoing multiterritory cerebral revascularization using a 3-vessel anastomosis from 2019 to 2023. RESULTS: Five patients met inclusion criteria (median age 53 years [range 12-73]). Three patients with complex middle cerebral artery aneurysms (1 ruptured) were treated with proximal ligation or partial/complete clip trapping and multiterritory external carotid artery-M2-M2 revascularization using a saphenous vein interposition graft. Two patients with moyamoya disease, prior strokes, and predominately bilateral anterior cerebral artery hypoperfusion were treated with proximal superficial temporal artery-A3-A3 revascularization using a radial artery or radial artery fascial flow-through free flap graft. No patients experienced significant surgery-related ischemia. Bypass patency was 100%. One patient had new strokes from vasospasm after subarachnoid hemorrhage. One patient required a revision surgery for subdural hematoma evacuation and radial artery fascial flow-through free flap debridement, without affecting bypass patency or neurologic outcome. On hospital discharge, median Glasgow Outcome Scale and modified Rankin Scale scores were 4 (range 3-5) and 2 (range 0-5), respectively. On follow-up, 1 patient died from medical complications of their presenting stroke; Glasgow Outcome Scale and modified Rankin Scale scores were otherwise stable or improved. CONCLUSION: The 3-vessel anastomosis technique can be considered for simultaneous revascularization of multiple intracranial territories.

Cilostazol for the management of moyamoya disease: a systematic review of the early evidence, efficacy, safety, and future directions.

Surgical revascularization remains the standard treatment for symptomatic moyamoya disease (MMD). As with any major surgical treatment, revascularization is associated with risks and limitations, denoting the need for noninvasive treatments to improve ischemic symptoms and prevent strokes. Cilostazol is a selective phosphodiesterase III inhibitor with antiplatelet, antithrombotic, and vasodilatory effects commonly used in peripheral vascular disease. Clinical studies assessing the efficacy of cilostazol in the management of stroke and MMD were recently reported, although a comprehensive assessment of the overall evidence is lacking. A systematic scoping review was conducted to assess the early evidence on cilostazol administration in patients with MMD. The inclusion criteria encompassed original human studies primarily focused on cilostazol's safety, efficacy, or utilization in managing MMD patients. A search of the PubMed database was conducted in June 2023, yielding 5 peer-reviewed publications that satisfied the inclusion criteria and were subjected to narrative synthesis. Risk of bias assessment was not applicable due to the scoping nature of this review. East Asian studies demonstrate increasing rates of cilostazol prescriptions for patients with MMD. In a large population-based study, cilostazol was compared to other antiplatelet medications and yielded the largest decrease in mortality among patients with newly diagnosed MMD. Other studies reported significant improvements in cerebral blood flow and cognitive function, which were deemed to be independent of one another. There are limited data on the safety profile of cilostazol in the MMD population, although the evidence derived from various studies performed in the general stroke population can likely provide insights into its potential utility in MMD patients. Cilostazol targets several critical pathways involved in the pathophysiology of MMD. The evidence corroborates the potential benefits of cilostazol for the management of MMD, although these findings should be interpreted with caution due to the small number of studies and lack of randomized trials. Subgroups of patients need to be identified who can safely undergo medical management in lieu of revascularization surgery or to improve surgical outcomes. Additional studies are needed to assess the efficacy and safety of cilostazol therapy, especially in Western populations.

A window to the brain: ultrasound imaging of human neural activity through a permanent acoustic window.

Recording human brain activity is crucial for understanding normal and aberrant brain function. However, available recording methods are either highly invasive or have relatively low sensitivity. Functional ultrasound imaging (fUSI) is an emerging technique that offers sensitive, large-scale, high-resolution neural imaging. However, fUSI cannot be performed through adult human skull. Here, we use a polymeric skull replacement material to create an acoustic window allowing ultrasound to monitor brain activity in fully intact adult humans. We design the window through experiments in phantoms and rodents, then implement it in a participant undergoing reconstructive skull surgery. Subsequently, we demonstrate fully non-invasive mapping and decoding of cortical responses to finger movement, marking the first instance of high-resolution (200 µm) and large-scale (50 mmx38 mm) brain imaging through a permanent acoustic window.

Combined open revascularization and endovascular treatment of complex intracranial aneurysms: case series.

Background and purpose: The treatment of complex intracranial aneurysms can be challenging with stand-alone open or endovascular techniques, particularly after rupture. A combined open and endovascular strategy can potentially limit the risk of extensive dissections with open-only techniques, and allow for aggressive definitive endovascular treatments with minimized downstream ischemic risk. Materials and methods: Retrospective, single-institution review of consecutive patients undergoing combined open revascularization and endovascular embolization/occlusion for complex intracranial aneurysms from 1/2016 to 6/2022. Results: Ten patients (4 male [40%]; mean age 51.9 ± 8.7 years) underwent combined open revascularization and endovascular treatment of intracranial aneurysms. The majority of aneurysms, 9/10 (90%), were ruptured and 8/10 (80%) were fusiform in morphology. Aneurysms of the posterior circulation represented 8/10 (80%) of the cases (vertebral artery [VA] involving the posterior inferior cerebellar artery [PICA] origin, proximal PICA or anterior inferior cerebellar artery/PICA complex, or proximal posterior cerebral artery). Revascularization strategies included intracranial-to-intracranial (IC-IC; 7/10 [70%]) and extracranial-to-intracranial (EC-IC; 3/10 [30%]) constructs, with 100% postoperative patency. Initial endovascular procedures (consisting of aneurysm/vessel sacrifice in 9/10 patients) were performed early after surgery (0.7 ± 1.5 days). In one patient, secondary endovascular vessel sacrifice was performed after an initial sub-occlusive embolization. Treatment related strokes were diagnosed in 3/10 patients (30%), largely from involved or nearby perforators. All bypasses with follow-up were patent (median 14.0, range 4-72 months). Good outcomes (defined as a Glasgow Outcomes Scale ≥4 and modified Rankin Scale ≤2) occurred in 6/10 patients (60%). Conclusion: A variety of complex aneurysms not amenable to stand-alone open or endovascular techniques can be successfully treated with combined open and endovascular approaches. Recognition and preservation of perforators is critical to treatment success.

Surgical Outcomes Following Vestibular Schwannoma Resection in Patients over the Age of Sixty-five.

Objective Vestibular schwannoma (VS) are benign, often slow growing neoplasms. Some institutions opt for radiosurgery in symptomatic patients of advanced age versus surgical resection. The aim of the study is to analyze surgical outcomes of VS in patients over the age of 65 who were either not candidates for or refused radiosurgery. Methods This includes retrospective analysis of VS patients between 1988 and 2020. Demographics, tumor characteristics, surgical records, and clinical outcomes were recorded. Patient preference for surgery over radiosurgery was recorded in the event that patients were offered both. Facial nerve outcomes were quantified using House-Brackmann (HB) scores. Tumor growth was defined by increase in size of >2 mm. Results In total, 64 patients were included of average age 72.4 years (65-84 years). Average maximum tumor diameter was 29 mm (13-55 mm). Forty-five patients were offered surgery or GKRS, and chose surgery commonly due to radiation aversion (48.4%). Gross total resection was achieved in 39.1% ( n = 25), near total 32.8% ( n = 21), and subtotal 28.1% ( n = 18). Average hospitalization was 5 days [2-17] with 75% ( n = 48) discharged home. Postoperative HB scores were good (HB1-2) in 43.8%, moderate (HB3-4) in 32.8%, and poor (HB5-6) in 23.4%. HB scores improved to good in 51.6%, moderate in 31.3%, and remained poor in 17.1%, marking a rate of facial nerve improvement of 10.9%. Tumor control was achieved in 95.3% of cases at an average follow-up time of 37.8 months. Conclusion VS resection can be safely performed in patients over the age of 65. Advanced age should not preclude a symptomatic VS patient from being considered for surgical resection.

Vagus nerve stimulation paired with rehabilitation for stroke: Implantation experience from the VNS-REHAB trial.

OBJECTIVE: Vagus Nerve Stimulation (VNS) paired with rehabilitation delivered by the Vivistim® Paired VNS™ System was approved by the FDA in 2021 to improve motor deficits in chronic ischemic stroke survivors with moderate to severe arm and hand impairment. Vagus nerve stimulators have previously been implanted in over 125,000 patients for treatment-resistant epilepsy and the surgical procedure is generally well-tolerated and safe. In this report, we describe the Vivistim implantation procedure, perioperative management, and complications for chronic stroke survivors enrolled in the pivotal trial. METHODS: The pivotal, multisite, randomized, triple-blind, sham-controlled trial (VNS-REHAB) enrolled 108 participants. All participants were implanted with the VNS device in an outpatient procedure. Thrombolytic agents were temporarily discontinued during the perioperative period. Participants were discharged within 48 hrs and started rehabilitation therapy approximately 10 days after the Procedure. RESULTS: The rate of surgery-related adverse events was lower than previously reported for VNS implantation for epilepsy and depression. One participant had vocal cord paresis that eventually resolved. There were no serious adverse events related to device stimulation. Over 90% of participants were taking antiplatelet drugs (APD) or anticoagulants and no adverse events or serious adverse events were reported as a result of withholding these medications during the perioperative period. CONCLUSIONS: This study is the largest, randomized, controlled trial in which a VNS device was implanted in chronic stroke survivors. Results support the use of the Vivistim System in chronic stroke survivors, with a safety profile similar to VNS implantations for epilepsy and depression.

Rethinking Cerebral Bypass Surgery.

Despite the evolution of indications, cerebral bypass remains an important treatment for selected patients with moyamoya disease, steno-occlusive cerebrovascular disease, complex aneurysms, and tumors. Ongoing advancements in patient selection and recent strategic, technical, and technological innovations are facilitating more tailored constructs with lower complication rates and continue to reshape the field. The consolidation of cerebral bypass to specialized centers will likely continue as the complexity of both the pathologies requiring treatment and the revascularization constructs performed increases.

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

BACKGROUND: 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. OBJECTIVE: To present our institutional experience using DLCFA grafts for cerebral revascularization. METHODS: Retrospective review of perioperative data and outcomes for patients undergoing cerebrovascular bypass surgery using a DLCFA graft from 2016 to 2019. RESULTS: 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). CONCLUSION: 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.

A Review of Medical and Surgical Options for the Treatment of Facial Pain.

Facial pain is a common medical complaint that is easily misdiagnosed. As a result, this pain often goes mistreated. Despite this, there are a variety of pharmacologic, surgical, and neuromodulatory options for the treatment of facial pain. In this review, the authors detail the forms of facial pain and their treatment options. They discuss the common medications used in the first-line treatment of facial pain and the second-line surgical and neuromodulatory options available to patients when pharmacologic options fail.

Cerebrovascular bypass for ruptured aneurysms: A case series.

In patients with aneurysmal subarachnoid hemorrhage (aSAH) unfavorable for endovascular or traditional open surgical techniques, surgical revascularization strategies comprise one of remaining limited options. There is nonetheless a paucity of data on the safety and efficacy of bypass in aSAH. In this study, we aimed to investigate complications and outcomes in a cohort of patients with aSAH treated with bypass. A prospective single-surgeon database of consecutive patients treated for aSAH between 2013 and 2018 was retrospectively analyzed. Complications and functional status at discharge were recorded and analyzed for the patients that underwent bypass surgery. Forty patients with aSAH were treated with bypass surgery (23 extracranial-intracranial; 17 intracranial-intracranial). All-cause perioperative mortality was 13% (6 patients). At discharge and at mean 14-month follow up, respectively, 16/40 (40%) and 16/25 (64%) of patients achieved a Glasgow Outcome Score of 4-5. All-cause, in-hospital complications occurred in 28 patients (70%), of which any ischemic complication occurred in 20 patients (50%), 7 (18%) being open surgical complications. This work represents the largest modern series of bypass for aSAH to date. In cases of aSAH unfavorable for endovascular intervention or traditional open surgical techniques, bypass remains a viable option in this complex group of patients.

Gray Matter Atrophy: The Impacts of Resective Surgery and Vagus Nerve Stimulation in Drug-Resistant Epilepsy.

BACKGROUND: There is great concern for cognitive function after resective temporal lobe surgery for drug-resistant epilepsy. However, few studies have investigated postoperative anatomical changes, and the downstream effects of surgery are poorly understood. This study investigated volumetric changes after resective surgery and vagus nerve stimulation (VNS) for epilepsy. METHODS: Preoperative and latest postoperative (mean, 28 months) structural T1 magnetic resonance imaging scans were retrospectively obtained for 43 patients: 27 temporal lobe resections (TLRs), 6 extratemporal lobe resections, and 10 VNS, undergoing surgery for drug-resistant epilepsy between 2012 and 2017. Automated volumetric analyses of predefined cortical gray matter and subcortical structures were performed. Preoperative and postoperative volumes were compared, and the effects of age, gender, operation type, resection laterality, selectivity, time since surgery, and seizure outcome on volumetric changes were analyzed. RESULTS: After TLRs, there were reductions in contralateral hemispheric gray matter, temporal lobe, entorhinal cortex, parahippocampal, superior temporal, middle temporal, inferior temporal (P = 0.02), lingual, fusiform, precentral, paracentral, postcentral, pericalcarine gyri, and ipsilateral superior parietal gyrus. After VNS, there was bilateral atrophy in the thalamus, putamen, cerebellum, rostral anterior cingulate, posterior cingulate, medial orbitofrontal, paracentral, fusiform, and transverse temporal gyri. There was a significant effect of surgery type but no effect of age, gender, operation type, resection laterality, selectivity, time since surgery, and seizure outcome on contralateral hippocampal gray matter change. CONCLUSION: This is the first study to demonstrate volumetric decreases in temporal and connected regions after TLRs and VNS. These results provide interesting insight into functional network changes.

Comparative Assessment of Extracranial-to-Intracranial and Intracranial-to-Intracranial In Situ Bypass for Complex Intracranial Aneurysm Treatment Based on Rupture Status: A Case Series.

BACKGROUND: Comparative outcomes of extracranial-to-intracranial (EC-IC) and intracranial-to-intracranial (IC-IC) bypass for complex aneurysm treatment based on rupture status are not well described in the literature. In this study, we compare outcomes of EC-IC and IC-IC bypass for complex intracranial aneurysm treatment based on rupture status. METHODS: A prospective neurosurgical patient database was retrospectively reviewed. Sixty-three consecutive patients with aneurysm managed with revascularization were identified between July 2014 and December 2018. RESULTS: During the study period, 41 patients with aneurysm underwent EC-IC bypass (65%; 24 [58.5%] ruptured, 17 [41.5%] unruptured) and 22 patients with aneurysm underwent IC-IC bypass (34.9%; 13 [59.1%] ruptured, 9 [40.9%] unruptured). Graft spasm occurred in 4 patients (9.8%) in the EC-IC group (all ruptured aneurysms) and all anastomoses were patent on immediate postoperative imaging. Perioperative mortality occurred in 5 patients who underwent EC-IC bypass (12.2%; 3 ruptured, 2 unruptured) EC-IC and 2 patients who underwent IC-IC bypass (9.1%; both ruptured); (P = 0.709). Bypass-related complications occurred only in patients with ruptured aneurysm (2 [8.3%] in the EC-IC group and 0 [0%] in the IC-IC group; P = 0.285). For unruptured aneurysms, the overall complication rate was lower in IC-IC compared with the EC-IC group (P = 0.006). Modified Rankin Scale scores on discharge were significantly lower in IC-IC compared with EC-IC bypass for unruptured aneurysms (P = 0.008). There was a trend for shorter temporary occlusion and hospitalization times and overall better outcomes with IC-IC compared with EC-IC bypass. CONCLUSIONS: Although often considered riskier than EC-IC bypass, IC-IC in situ bypass showd a favorable technical and safety profile for the treatment of complex, unruptured aneurysms.

An Expedited Transition to the Back Wall Suturing for Side-to-Side In Situ Microvascular Anastomosis: A Technique Update.

BACKGROUND: The side-to-side in situ microvascular anastomosis is an important tool in the cerebrovascular neurosurgeon's armamentarium. The execution of the side-to-side anastomosis, however, can be limited by the inability to acquire sufficient visualization and approximation of the recipient and donor vessels. OBJECTIVE: To expedite the transition to the back wall suturing of the donor and recipient vessels during side-to-side in situ microvascular anastomosis. METHODS: Incorporation of the first suture throw from the outside to the inside of the vessel lumen with the initial stay suture at the proximal apex of the arteriotomy is described. The apical knot is tied between one limb of the resultant loop and the free end of the suture. The remainder of side-to-side anastomosis can then be completed in a standard fashion starting from the inside of the lumen. RESULTS: This modification allows for an expedited transition to the back wall suturing of the 2 arterial segments and avoids difficulties associated with taking the first bite from behind the knot at the proximal apex of the arteriotomy or the transfer of the needle between the approximated vessels. This updated technique is illustrated with a case example, illustration, and video. CONCLUSION: This technical modification for the side-to-side anastomosis helps optimize microsurgical efficiency by limiting needle, suture, and vessel handling after the initial suture placement, which has classically been a challenge of this bypass.

Intentional Subtotal Resection of Vestibular Schwannoma: A Reexamination.

Background Treatment of vestibular schwannomas (VS) remains controversial. Historical surgical series prioritized gross total resections (GTR); however, near total resections (NTR) and intentional subtotal resections (STR) aiming at improving cranial nerve outcomes are becoming more popular. Objective The main purpose of this article is to assess the tumor control and facial nerve outcomes in VS patients treated with STR or NTR. Methods VS patients undergoing STR or NTR at our institution between 1984 and 2016 were retrospectively reviewed. Patient demographics, extent of tumor resection, facial nerve injury, tumor recurrence, and need for Gamma Knife radiosurgery were analyzed. Facial nerve outcomes were quantified using House-Brackmann (HB) scores. Tumor regrowth was defined by the San Francisco criteria. Results Four-hundred fifty-seven VS resections were performed in a 32-year period. Sixty cases met inclusion criteria. The mean (range) follow-up duration was 30.9 (12-103) months. The STR cohort ( n = 33) demonstrated regrowth in 12 patients (36.3%) at an average of 23.6 months. The NTR cohort ( n = 27) did not experience tumor recurrence. Risk of tumor recurrence was positively correlated with preoperative tumor size ( p = 0.002), size of residual tumor ( p < 0.001), and STR ( p < 0.001). Facial nerve outcomes of HB1-2 were observed in the majority of patients in both cohorts (74.1% NTR, 56% STR), though NTR was associated with a higher likelihood of facial nerve recovery ( p = 0.003). Conclusion GTR remains the gold standard as long as facial nerve outcomes remain acceptable. NTR achieved superior tumor control and higher likelihood of facial nerve recovery compared with STR.

Bypass and Deconstructive Technique for Hunt and Hess Grade 3-5 Aneurysmal Subarachnoid Hemorrhage Deemed Unfavorable for Endovascular Treatment: Case Series of Outcomes and Comparison with Clipping.

BACKGROUND: Intracranial bypass to treat ruptured aneurysms has been well described in the literature but is largely deferred in patients with higher Hunt and Hess (H & H) grades due to complexity and length of surgery, risk of inducing vasospasm, and poor prognosis. However, there is a paucity of data and no direct comparison with more traditional open surgical techniques. This study investigated outcomes in patients with H & H grade 3-5 aneurysmal subarachnoid hemorrhage (aSAH) unfavorable for stand-alone endovascular treatment managed with bypass compared with direct surgical clipping. METHODS: A prospective database of patients treated for aSAH with H & H grade 3-5 between 2013 and 2018 was retrospectively analyzed. Complications and functional status at discharge and latest follow-up were compared between patients who underwent bypass surgery versus direct clipping. RESULTS: Twenty-three patients underwent revascularization, and 60 underwent clipping alone. There were no significant differences in all-cause 30-day mortality (15% vs. 16%; P = 0.97) or Glasgow Outcome Scale and modified Rankin Scale at discharge or median 8-month follow-up (P > 0.67). There was a higher overall stroke rate with revascularization (P = 0.004), specifically endovascular treatment-related stroke (P = 0.049), with no difference in surgical (P = 0.47) or vasospasm-related stroke (P = 0.53). There were no differences in overall complications, medical complications, seizures, reruptures, hydrocephalus, or perioperative death (P > 0.05). CONCLUSIONS: Bypass is a viable option for patients presenting with higher H & H grade aSAH deemed unfavorable for stand-alone endovascular therapy. Despite obvious differences in aneurysm complexity and a higher risk of stroke, functional outcomes with revascularization can be comparable with clipping in this high-risk patient cohort.