Risk of Cerebral Aneurysm Rupture After Liver Transplantation: Development and Validation of a Hemorrhagic Stroke Scoring Model.

BACKGROUND: Liver transplantation (LT) patients appear to be more prone to neurological events compared to individuals undergoing other types of solid-organ transplantation. The aims of the present study were to analyze the prevalence of unruptured intracranial aneurysms (UIAs) in patients undergoing liver transplantation (LT) and to examine the perioperative occurrence of subarachnoid hemorrhage (SAH). Also, it intended to systematically identify the risk factors of SAH and hemorrhagic stroke (HS) within a year after LT and to develop a scoring system which involves distinct clinical features of LT patients. METHODS: Patients who underwent LT from January 2012 to March 2022 were analyzed. All included patients underwent neurovascular imaging within 6 months before LT. We conducted an analysis of prevalence and radiological features of UIA and SAH. The clinical factors that may have an impact on HS within one year of LT were also reviewed. RESULTS: Total of 3,487 patients were enrolled in our study after applying inclusion and exclusion criteria. The prevalence of UIA was 5.4%. The incidence of SAH and HS within one year following LT was 0.5% and 1.6%, respectively. We developed a scoring system based on multivariable analysis to predict the HS within 1-year after LT. The variables were a poor admission mental status, the diagnosis of UIA, serum ammonia levels, and Model for End-stage Liver Disease (MELD) scores. Our model showed good discrimination among the development (C index, 0.727; 95% confidence interval [CI], 0.635-0.820) and validation (C index, 0.719; 95% CI, 0.598-0.801) cohorts. CONCLUSION: The incidence of UIA and SAH was very low in LT patients. A poor admission mental status, diagnosis of UIA, serum ammonia levels, and MELD scores were significantly associated with the risk of HS within one year after LT. Our scoring system showed a good discrimination to predict the HS in LT patients.

Chemical and perfusion markers as predictors of moyamoya disease progression and complication types.

To investigate the association between chemical markers (triglyceride, C-reactive protein (CRP), and inflammation markers) and perfusion markers (relative cerebral vascular reserve (rCVR)) with moyamoya disease progression and complication types. A total of 314 patients diagnosed with moyamoya disease were included. Triglyceride and CRP levels were assessed and categorized based on Korean guidelines for dyslipidemia and CDC/AHA guidelines, respectively. Perfusion markers were evaluated using Diamox SPECT. Cox proportional hazard analysis was performed to examine the relationship between these markers and disease progression, as well as complication types (ischemic stroke, hemorrhagic stroke, and rCVR deterioration). Elevated triglyceride levels (≥ 200) were significantly associated with higher likelihood of end-point events (HR: 2.292, CI 1.00-4.979, P = 0.03). Severe decreased rCVR findings on Diamox SPECT were also significantly associated with end-point events (HR: 3.431, CI 1.254-9.389, P = 0.02). Increased CRP levels and white blood cell (WBC) count were significantly associated with moyamoya disease progression. For hemorrhagic stroke, higher triglyceride levels were significantly associated with end-point events (HR: 5.180, CI 1.355-19.801, P = 0.02). For ischemic stroke, severe decreased rCVR findings on Diamox SPECT (HR: 5.939, CI 1.616-21.829, P < 0.01) and increased CRP levels (HR: 1.465, CI 1.009-2.127, P = 0.05) were significantly associated with end-point events. Elevated triglyceride, CRP, and inflammation markers, as well as decreased rCVR, are potential predictors of moyamoya disease progression and complication types. Further research is warranted to understand their role in disease pathophysiology and treatment strategies.

The Unique Relationship between Neuro-Critical Care and Critical Illness-Related Corticosteroid Insufficiency : Implications for Neurosurgeons in Neuro-Critical Care.

The brain houses vital hormonal regulatory structures such as the hypothalamus and pituitary gland, which may confer unique susceptibilities to critical illness-related corticosteroid insufficiency (CIRCI) in patients with neurological disorders. In addition, the frequent use of steroids for therapeutic purposes in various neurological conditions may lead to the development of steroid insufficiency. This abstract aims to highlight the significance of understanding these relationships in the context of patient care and management for physicians. Neurological disorders may predispose patients to CIRCI due to the role of the brain in hormonal regulation. Early recognition of CIRCI in the context of neurological diseases is essential to ensure prompt and appropriate intervention. Moreover, the frequent use of steroids for treating neurological conditions can contribute to the development of steroid insufficiency, further complicating the clinical picture. Physicians must be aware of these unique interactions and be prepared to evaluate and manage patients with CIRCI and steroid insufficiency in the context of neurological disorders. This includes timely diagnosis, appropriate steroid administration, and careful monitoring for potential adverse effects. A comprehensive understanding of the interplay between neurological disease, CIRCI, and steroid insufficiency is critical for optimizing patient care and outcomes in this complex patient population.

Aquaporin-4 Deficiency is Associated with Cognitive Impairment and Alterations in astrocyte-neuron Lactate Shuttle.

Cognitive impairment refers to notable declines in cognitive abilities including memory, language, and emotional stability leading to the inability to accomplish essential activities of daily living. Astrocytes play an important role in cognitive function, and homeostasis of the astrocyte-neuron lactate shuttle (ANLS) system is essential for maintaining cognitive functions. Aquaporin-4 (AQP-4) is a water channel expressed in astrocytes and has been shown to be associated with various brain disorders, but the direct relationship between learning, memory, and AQP-4 is unclear. We examined the relationship between AQP-4 and cognitive functions related to learning and memory. Mice with genetic deletion of AQP-4 showed significant behavioral and emotional changes including hyperactivity and instability, and impaired cognitive functions such as spatial learning and memory retention. 18 F-FDG PET imaging showed significant metabolic changes in the brains of AQP-4 knockout mice such as reductions in glucose absorption. Such metabolic changes in the brain seemed to be the direct results of changes in the expression of metabolite transporters, as the mRNA levels of multiple glucose and lactate transporters in astrocytes and neurons were significantly decreased in the cortex and hippocampus of AQP-4 knockout mice. Indeed, AQP-4 knockout mice showed significantly higher accumulation of both glucose and lactate in their brains compared with wild-type mice. Our results show that the deficiency of AQP-4 can cause problems in the metabolic function of astrocytes and lead to cognitive impairment, and that the deficiency of AQP4 in astrocyte endfeet can cause abnormalities in the ANLS system.

Nutrition Therapy for Patients With Traumatic Brain Injury: A Narrative Review.

Traumatic brain injury (TBI) is a global health and socio-economic problem, resulting in significant disability and mortality. Malnutrition is common in TBI patients and is associated with increased vulnerability to infection, higher morbidity and mortality rates, as well as longer stays in the intensive care unit and hospital. Following TBI, various pathophysiological mechanisms, such as hypermetabolism and hypercatabolism, affect patient outcomes. It is crucial to provide adequate nutrition therapy to prevent secondary brain damage and promote optimal recovery. This review includes a literature review and discusses the challenges encountered in clinical practice regarding nutrition in TBI patients. The focus is on determining energy requirements, timing and methods of nutrition delivery, promoting enteral tolerance, providing enteral nutrition to patients receiving vasopressors, and implementing trophic enteral nutrition. Enhancing our understanding of the current evidence regarding appropriate nutrition practices will contribute to improving overall outcomes for TBI patients.

Recent Updates on Controversies in Decompressive Craniectomy and Cranioplasty: Physiological Effect, Indication, Complication, and Management.

Decompressive craniectomy (DCE) and cranioplasty (CP) are surgical procedures used to manage elevated intracranial pressure (ICP) in various clinical scenarios, including ischemic stroke, hemorrhagic stroke, and traumatic brain injury. The physiological changes following DCE, such as cerebral blood flow, perfusion, brain tissue oxygenation, and autoregulation, are essential for understanding the benefits and limitations of these procedures. A comprehensive literature search was conducted to systematically review the recent updates in DCE and CP, focusing on the fundamentals of DCE for ICP reduction, indications for DCE, optimal sizes and timing for DCE and CP, the syndrome of trephined, and the debate on suboccipital CP. The review highlights the need for further research on hemodynamic and metabolic indicators following DCE, particularly in relation to the pressure reactivity index. It provides recommendations for early CP within three months of controlling increased ICP to facilitate neurological recovery. Additionally, the review emphasizes the importance of considering suboccipital CP in patients with persistent headaches, cerebrospinal fluid leakage, or cerebellar sag after suboccipital craniectomy. A better understanding of the physiological effects, indications, complications, and management strategies for DCE and CP to control elevated ICP will help optimize patient outcomes and improve the overall effectiveness of these procedures.

Optimizing Mannitol Use in Managing Increased Intracranial Pressure: A Comprehensive Review of Recent Research and Clinical Experiences.

Mannitol, derived from mannose sugar, is crucial in treating patients with elevated intracranial pressure (ICP). Its dehydrating properties at the cellular and tissue levels increase plasma osmotic pressure, which is studied for its potential to reduce ICP through osmotic diuresis. While clinical guidelines support mannitol use in these cases, the best approach for its application continues to be debated. Important aspects needing further investigation include: 1) bolus administration versus continuous infusion, 2) ICP-based dosing versus scheduled bolus, 3) identifying the optimal infusion rate, 4) determining the appropriate dosage, 5) establishing fluid replacement plans for urinary loss, and 6) selecting monitoring techniques and thresholds to assess effectiveness and ensure safety. Due to the lack of adequate high-quality prospective research data, a comprehensive review of recent studies and clinical trials is crucial. This assessment aims to bridge the knowledge gap, improve understanding of effective mannitol use in elevated ICP patients, and provide insights for future research. In conclusion, this review aspires to contribute to the ongoing discourse on mannitol application. By integrating the latest findings, this review will offer valuable insights into the function of mannitol in decreasing ICP, thereby informing better therapeutic approaches and enhancing patient outcomes.

Efficacy of Acetylcysteine and Selenium in Aneurysmal Subarachnoid Hemorrhage Patients: A Prospective, Multicenter, Single Blind Randomized Controlled Trial.

BACKGROUND: Subarachnoid hemorrhage (SAH) patients have oxidative stress results in inflammation, tissue degeneration and neuronal damage. These deleterious effects cause aggravation of the perihematomal edema (PHE), vasospasm, and even hydrocephalus. We hypothesized that antioxidants may have a neuroprotective role in acute aneurysmal SAH (aSAH) patients. METHODS: We conducted a prospective, multicenter randomized (single blind) trial between January 2017 and October 2019, investigating whether antioxidants (acetylcysteine and selenium) have the potential to improve the neurologic outcome in aSAH patients. The antioxidant patient group received antioxidants of acetylcysteine (2,000 mg/day) and selenium (1,600 µg/day) intravenously (IV) for 14 days. These drugs were administrated within 24 hours of admission. The non-antioxidant patient group received a placebo IV. RESULTS: In total, 293 patients were enrolled with 103 patients remaining after applying the inclusion and exclusion criteria. No significant differences were observed in the baseline characteristics between the antioxidant (n = 53) and non-antioxidant (n = 50) groups. Among clinical factors, the duration of intensive care unit (ICU) stay was significantly shortened in patients who received antioxidants (11.2, 95% confidence interval [CI], 9.7-14.5 vs. 8.3, 95% CI, 6.2-10.2 days, P = 0.008). However, no beneficial effects were observed on radiological outcomes. CONCLUSION: In conclusion, antioxidant treatment failed to show the reduction of PHE volume, mid-line shifting, vasospasm and hydrocephalus in acute SAH patients. A significant reduction in ICU stay was observed but need more optimal dosing schedule and precise outcome targets are required to clarify the clinical impacts of antioxidants in these patients. TRIAL REGISTRATION: Clinical Research Information Service Identifier: KCT0004628.

The Unique Relationship between Neuro-Critical Care and Critical Illness-Related Corticosteroid Insufficiency : Implications for Neurosurgeons in Neuro-Critical Care.

The brain houses vital hormonal regulatory structures such as the hypothalamus and pituitary gland, which may confer unique susceptibilities to critical illness-related corticosteroid insufficiency (CIRCI) in patients with neurological disorders. In addition, the frequent use of steroids for therapeutic purposes in various neurological conditions may lead to the development of steroid insufficiency. This abstract aims to highlight the significance of understanding these relationships in the context of patient care and management for physicians. Neurological disorders may predispose patients to CIRCI due to the role of the brain in hormonal regulation. Early recognition of CIRCI in the context of neurological diseases is essential to ensure prompt and appropriate intervention. Moreover, the frequent use of steroids for treating neurological conditions can contribute to the development of steroid insufficiency, further complicating the clinical picture. Physicians must be aware of these unique interactions and be prepared to evaluate and manage patients with CIRCI and steroid insufficiency in the context of neurological disorders. This includes timely diagnosis, appropriate steroid administration, and careful monitoring for potential adverse effects. A comprehensive understanding of the interplay between neurological disease, CIRCI, and steroid insufficiency is critical for optimizing patient care and outcomes in this complex patient population.

Survival Outcomes and Predictors for Recurrence of Surgically Treated Brain Metastasis From Non-Small Cell Lung Cancer.

BACKGROUND: There are numerous factors to consider in deciding whether to undergo surgical treatment for brain metastasis from lung cancer. Herein, we aimed to analyze the survival outcome and predictors of recurrence of surgically treated brain metastasis from non-small cell lung cancer (NSCLC). METHODS: A total of 197 patients with brain metastasis from NSCLC who underwent microsurgery were included in this study. RESULTS: A total of 114 (57.9%) male and 83 (42.1%) female patients with a median age of 59 years (range, 27-79) was included in this study. The median follow-up period was 22.7 (range, 1-126) months. The 1-year and 2-year overall survival (OS) rates of patients with brain metastasis secondary to NSCLC were 59% and 43%, respectively. The 6-month and 1-year progression-free survival (PFS) rates of local recurrence were 80% and 73%, respectively, whereas those of distant recurrence were 84% and 63%, respectively. En-bloc resection of tumor resulted in better PFS for local recurrence (1-year PFS: 79% vs. 62%, p=0.02). Ventricular opening and direct contact between the tumor and the subarachnoid space were not associated with distal recurrence and leptomeningeal seeding. The difference in PFS of local recurrence according to adjuvant resection bed irradiation was not significant. Moreover, postoperative whole-brain irradiation did not show a significant difference in PFS of distant recurrence. In multivariate analysis, only en-bloc resection was a favorable prognostic factor for local recurrence. Contrastingly, multiple metastasis was a poor prognostic factor for distant recurrence. CONCLUSION: En-bloc resection may reduce local recurrence after surgical resection. Ventricular opening and contact between the tumor and subarachnoid space did not show a statistically significant result for distant recurrence and leptomeningeal seeding. Multiple metastasis was only meaningful factor for distant recurrence.

Extraventricular Neurocytoma: Clinical Investigation of Heterogenous Prognosis.

BACKGROUND: Extraventricular neurocytoma (EVN) is an extremely rare neuronal neoplasm that arises outside the ventricle. The clinical implication of the heterogenous prognosis of this rare tumor has not yet been clarified. Herein, we analyzed our institutional series of EVN. METHODS: A total of eight consecutive cases were enrolled and investigated. The prognosis of EVN was analyzed and compared to that of central neurocytoma (CN). RESULTS: There were two male and six female patients, and the median age was 36.5 years. The median tumor size was 38 mm, and the most common location of the tumor was the frontal lobe (3, 37.5%), followed by the parietal and temporal lobes. In brain imaging, four (50%) tumors showed peritumoral edema and three (37.5%) tumors showed calcification. All patients underwent gross total resection, and two (25%) underwent adjuvant radiotherapy. The 5-year overall survival (OS) was 55.6%, and the 2-year progression-free survival (PFS) was 42.9%. The OS and PFS of EVN were poor compared to those of CN. Although EVN is a single disease entity, individual patients showed varying prognosis. One patient showed no recurrence during the 7-year follow-up period; however, another patient had a recurrence 4 months after surgery and died 2 years later. CONCLUSION: EVN may be a heterogenous disease entity. Additional cases with long-term followup are needed to develop optimal management protocols.

The Influence of Neurological Disorders Before Cardiac Myxoma Surgery on the Rate of Postoperative Recurrences: Analysis of 317 Patients in a Single Center.

BACKGROUND: Cardiac myxoma is a very rare disease for which resection is the gold standard treatment. Many neurological manifestations are associated with this disease, including embolic infarctions, arterial aneurysms, and brain metastatic myxomas, but few large-scale studies have addressed this. The aim of this study was to retrospectively analyze the incidence, type, and prognosis of these neurological disorders. METHODS: We enrolled 317 patients who underwent a cardiac myxoma resection between 2004 and 2019 at our institution. A retrospective review of medical records and radiological imaging was performed for each patient, and clinical factors were compared and analyzed with regard to clinical outcomes and the incidence of adverse events. RESULTS: Patients with a neurological disorder before surgery were found to be more likely to develop new postoperative neurological complications (P = 0.003). Patients with a neurological disorder arising at any time before or after surgery had poorer outcomes (P < 0.001). CONCLUSIONS: The clinical management of cardiac myxoma must take account of neurological sequelae independently of the surgical intervention to remove the lesion. Patients with cardiac myxoma and any neurological disorder should undergo both neurosurgical follow-up and cardiac surgical follow-up, even if myxoma removal surgery has been performed. We recommend active neuroimaging during long-term follow-up as essential in these cases.

Treatment Outcome and Risk Factors Associated with Diffuse Axonal Injury in Patients with Moderate to Severe Head Injury.

AIM: To evaluate diffuse axonal injury (DAI) patients according to DAI stage to identify risk factors that may affect clinical outcome. MATERIAL AND METHODS: A total of 992 traumatic brain injury (TBI) patients visited our hospital between 2011 and 2016. Thirtyseven patients diagnosed with DAI were enrolled in this study and stratified by DAI stage: Stage I, 20 patients (54.1%); Stage II, 4 patients (10.8%); and Stage III, 13 patients (35.1%). RESULTS: The mean age and the median follow-up period were 45.43 years and 13 months, respectively. Patient demographic data and clinical findings on admission showed no differences according to DAI stage, except for the revised trauma score (RTS) (p=0.026). In univariate analysis, stages I and II vs. III (p=0.001) and stages I vs. II and III (p=0.019), transfusion within 24 hours of visit (p=0.033), shock or cardiac arrest (p=0.006), traumatic subarachnoid hemorrhage (T-SAH) (p=0.011), and subdural hematoma (SDH) (p=0.009) were significantly correlated with Glasgow outcome score (GOS). In multivariate analysis, DAI stage I and II vs. III (p=0.005) and SDH (p=0.040) were significant. CONCLUSION: Clinically, Stage II was more correlated with Stage I, rather than stage III. Stage III showed a much poorer outcome compared to stages I and II. Magnetic resonance imaging (MRI) should be promptly performed in all TBI patients when a patient?s level of consciousness and cranialcomputed tomography (CT) does not match, as there is a possibility of stage III DAI.

Posterior Thoracic Cage Interbody Fusion Offers Solid Bone Fusion with Sagittal Alignment Preservation for Decompression and Fusion Surgery in Lower Thoracic and Thoracolumbar Spine.

OBJECTIVE: It is challenging to make solid fusion by posterior screw fixation and laminectomy with posterolateral fusion (PLF) in thoracic and thoracolumbar (TL) diseases. In this study, we report our experience and follow-up results with a new surgical technique entitled posterior thoracic cage interbody fusion (PTCIF) for thoracic and TL spine in comparison with conventional PLF. METHODS: After institutional review board approval, a total of 57 patients who underwent PTCIF (n=30) and conventional PLF (n=27) for decompression and fusion in thoracic and TL spine between 2004 and 2019 were analyzed. Clinical outcomes and radiological parameters, including bone fusion, regional Cobb angle, and proximal junctional Cobb angle, were evaluated. RESULTS: In PTCIF and conventional PLF, the mean age was 61.2 and 58.2 years (p=0.46), and the numbers of levels fused were 2.8 and 3.1 (p=0.46), respectively. Every patient showed functional improvement except one case of PTCIF. Postoperative hematoma as a perioperative complication occurred in one and three cases, respectively. The mean difference in the regional Cobb angle immediately after surgery compared with that of the last follow-up was 1.4° in PTCIF and 7.6° in conventional PLF (p=0.003), respectively. The mean durations of postoperative follow-up were 35.6 months in PTCIF and 37.3 months in conventional PLF (p=0.86). CONCLUSION: PTCIF is an effective fusion method in decompression and fixation surgery with good clinical outcomes for various spinal diseases in the thoracic and TL spine. It provides more stable bone fusion than conventional PLF by anterior column support.

Upregulation of AQP4 Improves Blood-Brain Barrier Integrity and Perihematomal Edema Following Intracerebral Hemorrhage.

In intracerebral hemorrhage (ICH), delayed secondary neural damages largely occur from perihematomal edema (PHE) resulting from the disruption of the blood-brain barrier (BBB). PHE is often considered the principal cause of morbidity and mortality in patients with ICH. Nevertheless, the main cellular mechanism as well as the specific BBB component involved in the formation of PHE after ICH remains elusive. Herein, we evaluated the role of AQP4, a water channel expressed on the astrocytes of the BBB, in the formation of PHE in ICH. The static and dynamic functions of the BBB were evaluated by analyzing the microstructure and leakage assay. Protein changes in the PHE lesion were analyzed and the control mechanism of AQP4 expression by reactive oxygen species was also investigated. Delayed PHE formation due to BBB disruption after ICH was confirmed by the decreased coverage of multiple BBB components and increased dynamic leakages. Microstructure assay showed that among the BBB components, AQP4 showed a markedly decreased expression in the PHE lesions. The decrease in AQP4 was due to microenvironmental ROS derived from the hemorrhage and was restored by treatment with ROS scavenger. AQP4-deficient mice had significantly larger PHE lesions and unfavorable survival outcomes compared with wild-type mice. Our data identify AQP4 as a specific BBB-modulating target for alleviating PHE in ICH. Further comprehensive studies are needed to form the preclinical basis for the use of AQP4 enhancers as BBB modulators for preventing delayed cerebral edema after ICH.

Reactive Oxygen Species Scavenger in Acute Intracerebral Hemorrhage Patients: A Multicenter, Randomized Controlled Trial.

[Figure: see text].

Clinical features of ischemic complications after unruptured middle cerebral artery aneurysm clipping: patients and radiologically related factors.

Postoperative ischemic complication results in neurological sequelae and longer hospitalization after unruptured middle cerebral artery (MCA) aneurysm clipping surgery. We evaluated the radiological and patient-related factors associated with ischemic complications after unruptured MCA aneurysm clipping surgery. Patient demographics, radiological findings, and intraoperative factors were compared between patients with and without postoperative ischemic complications. The clinical courses and outcomes of postoperative ischemic complications were compared according to the types of ischemic complication. Forty-two out of 2227 patients (1.9%) developed postoperative ischemic complications after MCA aneurysm clipping. Multivariate analysis revealed that diabetes mellitus (DM) was a patient-related factor. Intraarterial (IA) calcification of the distal internal carotid artery (ICA), preoperative M1 stenosis, and M1 aneurysm were radiological factors that increased the risk of postoperative ischemic complications. DM was significantly associated with divisional branch territory infarction (P = 0.04). The time to first presentation of ischemic complication was significantly longer in divisional branch territory infarction than perforator territory infarction (67.8 ± 75.9 h vs. 22 ± 20.7, P = 0.023). Twelve out of 42 patients with ischemic complications (28.6%) had unfavorable outcome (mRS > 3). Perforator territory infarction was significantly associated with an unfavorable outcome (mRS > 3, P = 0.019). IA calcification of the distal ICA, M1 stenosis and aneurysms, and DM were significantly associated with postoperative ischemic complications after unruptured MCA aneurysm clipping. Patients with DM should be closely monitored postoperatively to detect delayed occurrence of divisional branch infarction. Trial registration number: 2019-1002, Date of registration: January 1, 2005, "retrospectively registered".

Clinical Interrogation of Mandatory Insertion of Central Venous Catheter for Clipping Surgery of Unruptured Intracranial Aneurysm: A Propensity Score Matched Study.

BACKGROUND AND OBJECTIVE: Microsurgical clipping, along with endovascular treatment, has evolved in the treatment of unruptured intracranial aneurysms (UIA), and these developments have resulted in a reduction of the complication rate. We discuss the need for a central venous catheter (CVC) insertion as an anesthetic preparation for microsurgical clipping. METHODS: Between January 2019 and September 2019, 722 patients with UIA were treated at our institution. We excluded patients with a history of endovascular treatment or bypass surgery, recurrent aneurysms after coil embolization, brain tumors, or subarachnoid hemorrhages. A total of 272 patients were enrolled. Eighty-four patients underwent CVC insertion, and 188 patients underwent clipping surgery without CVC insertion. Outcome-related factors were compared between the 2 groups. We performed propensity score matching of the 2 groups to increase comparability. RESULTS: There were no significant differences in outcome, sex, aneurysm location, aneurysm multiplicity, aneurysm size, or comorbid disease between the 2 groups. The mean age at the time of surgery was higher in the non-CVC insertion group than in the CVC insertion group. There were no meaningful differences in primary outcomes, including premature rupture and intraoperative motor evoked potential/somatosensory evoked potential change, and secondary outcomes, including estimated blood loss, duration of intensive care unit stay, duration of hospitalization, and Glasgow Outcome Scale score at discharge. CONCLUSIONS: CVC insertion for clipping surgery for UIA is not mandatory. Considering the possible complications associated with CVCs, we cautiously suggest aneurysm surgery with CVC insertion in patients with serious medical comorbidities, aneurysm sizes >10 mm, and difficult proximal parent artery control.

Middle Cerebral Artery-to-Middle Cerebral Artery Bypass with Superficial Temporal Artery Interposition Graft for the Treatment of Recurrent Thrombosed Middle Cerebral Artery Aneurysm.

Microsurgical treatment of thrombosed middle cerebral artery (MCA) aneurysm is very complicated, especially in recurrent cases. A 48-year-old man presented with a recurrent thrombosed right MCA aneurysm. We performed MCA-to-MCA bypass using a superficial temporal artery (STA) interposition graft and proximal trapping. Initially, an STA-to-MCA bypass with aneurysm trapping was planned because 1 MCA branch of the superior trunk of the M2 segment needed flow replacement after aneurysm trapping. However, the blood flow from the proximal STA was insufficient because of the previous surgical trauma and redo clipping was not feasible. As the backflow from the distal STA segment was good, we used it as an interposition graft for the MCA-to-MCA bypass. The patient recovered well without any neurologic deficits. In this case, the recurrent aneurysm was a fusiform MCA-M2 segment aneurysm with clip slippage. Our initial surgical plan could not be executed. We changed our surgical plan to an MCA-interposition graft-MCA bypass considering the mobility of the M3 arteries. The options for interposition grafts included radial artery, saphenous vein, or ipsilateral or contralateral STA. The caliber discrepancy in the radial artery or saphenous vein grafts makes them less suitable. Further, harvesting the contralateral STA is time-consuming and tedious. Thus the ipsilateral STA interposition graft was used and showed promising results. We recommend this surgical technique in cases in which good STA backflow is guaranteed. In conclusion, revision surgery performed for a recurrent thrombosed MCA aneurysm with an MCA-STA interposition graft-MCA bypass with proximal trapping was successful. This technique is safe and effective for complex aneurysms with suboptimal condition of the STA, which could be due to reduced blood flow, previous surgery, or trauma.

Development and validation of a risk scoring model for postoperative adult moyamoya disease.

OBJECTIVE: The current grading system for moyamoya disease (MMD) is focused on angiographic studies with limited clinical application. The authors aimed to determine relevant factors that may impact postoperative outcome and establish a scoring system to predict the functional outcome. METHODS: Adult patients with MMD who underwent treatment between 1998 and 2016 were included. Factors such as age, sex, comorbidity, smoking, MMD family history, initial presentation, multimodal imaging modalities, and types of surgical revascularization were thoroughly reviewed. These factors were analyzed to determine possible risk factors related to unfavorable 6-month postoperative outcomes using the modified Rankin Scale (mRS) (unfavorable: mRS score ≥ 3). A scoring system was developed using these independent risk factors to predict the outcome and validated using prospectively collected data from multiple centers between 2017 and 2018. RESULTS: Of 302 patients for whom applications were submitted, 260 patients (321 hemispheres) met the diagnostic criteria. In multivariate analysis, hyperlipidemia, smoking, cerebral infarction on preoperative CT or MRI, and moderately to severely reduced regional cerebrovascular reserve results from Diamox SPECT were significantly related to unfavorable outcome. The authors developed a scoring system and stratified patients into risk groups according to their scores: low-risk (score 0-3), intermediate-risk (score 4-6), and high-risk (score 7-9) groups. This model demonstrated both good discrimination and calibration using C-statistics and the Hosmer-Lemeshow goodness-of-fit test showing 0.812 (95% CI 0.743-0.881) (p = 0.568) for the development and 0.954 (95% CI 0.896-1) (p = 0.097) for the temporal and external validation cohort. CONCLUSIONS: The authors' scoring system is readily adoptable to predict the postoperative outcome for MMD. Their data revealed the importance of smoking and hyperlipidemia, which were the only modifiable factors included in the scoring system. The authors validated their scoring system both internally and externally and maintained good performance, highlighting the system's generalizability and reliability.