The role of precentral cerebellar vein in neurosurgery: An in-depth review of anatomy, implications, and risks.

Background: The Precentral Cerebellar Vein (PCV) plays a crucial role as an anatomical landmark in neurosurgery, and the possibility of its safe sacrifice is controversial. Understanding its anatomical nuances and clinical implications is fundamental in enhancing neurosurgical practice. Methods: A systematic review following PRISMA guidelines was conducted to consolidate literature on the PCV. PubMed, Scopus, and Web of Science were systematically searched using predefined criteria. Studies providing complete research texts in English, focusing on the PCV's surgical anatomy and neurosurgical implications were included. Results: Fourteen articles met inclusion criteria, exploring the PCV's anatomical variations, trajectory, dimensions, and connections. The PCV's utility in localizing posterior fossa tumors was underscored, aiding in surgical precision. However, sacrifices of the PCV or minor veins for access to quadrigeminal areas posed postoperative risks, emphasizing the need for careful preoperative planning. Additionally, the PCV's diagnostic value in venous malformations and developmental anomalies was highlighted. Conclusions: This comprehensive review accentuates the pivotal role of the PCV in neurosurgery. While serving as a vital guide in procedures, it poses potential risks when manipulated. Understanding its multifaceted significance, from anatomy to clinical implications, is paramount for informed decision-making and minimizing complications in neurosurgical interventions.

Improved outcomes among octogenarians with ruptured aneurysms: endovascular treatment as right-of-first-refusal in the 2nd post-trial decade.

BACKGROUND: Treatment outcomes of octogenarians with aneurysmal subarachnoid hemorrhage (aSAH), are often considered poor. With ongoing advancements and experience in endovascular technology, we sought to evaluate the outcomes of octogenarians treated for aSAH in the second post-ISAT/BRAT trial decade. METHOD: A single-center database of aSAH was reviewed to identify patients aged 80 or above undergoing aneurysm treatment. Mortality and favorable neurological outcome (defined as mRS <3) were assessed among the series and compared across several subgroups. RESULTS: Octogenarian patients constituted 6% of the aSAH cohort (38/619) over the reviewed period. Twenty-one percent were high grade (Hunt-Hess IV-V). Endovascular treatment was the first-line modality in 90% of patients. During a median follow-up of 17 months, the overall mortality was 39%. Higher mortality was associated with poor Hunt-Hess grade (100% for Grade-V, 47% for III-IV, 13% for I-II, P=0.004) and non-independent baseline function status (100% mortality for non-independent vs. 28% for independent group, P=0.002). At last follow-up, 53% of patients achieved a favorable neurological outcome. The stratified rate was 80% in Hunt-Hess grade I-II and over 60% in patients with premorbid independent function status or less than 5 frailty components (P≤0.02 vs. poorer counterparts). CONCLUSION: Neurological outcomes of octogenarian patients with aSAH are improving in the second post-trial decade, particularly given the preponderance of endovascular treatment. Baseline functional status and comorbidities of octogenarians should be considered in addition to the Hunt-Hess grade in prognostication.

Sustained efficacy of angioplasty for cerebral vasospasm after aneurysmal subarachnoid hemorrhage: Risk features and device comparison.

BACKGROUND: Cerebral vasospasm is a leading source of delayed morbidity and mortality after aneurysmal subarachnoid hemorrhage (aSAH). Angioplasty may improve vasospasm, while optimal target and device selection remains controversial. This study aimed to identify features and devices associated with sustained efficacy. METHODS: We identified consecutive patients who underwent angioplasty for aSAH vasospasm. The primary outcome was a composite of adequate angioplasty (residual narrowing < 50 %) without complications. Secondary outcomes included rates of refractory/recurrent vasospasm and sustained improvement at follow-up. Associated features were identified through multivariable analysis. Outcomes were compared between balloon and Comaneci/stentriever in a propensity-score-matched cohort. RESULTS: A total of 149 vasospastic segments underwent angioplasty: 61.7 % in the proximal anterior circulation (ICA, M1, A1), 20.1 % in distal segments (A2 and M2) and 18.1 % in the posterior circulation. Adequate angioplasty was achieved without complication in 83.2 % of vessels, with a sustainable effect in 84.3 % at follow-up. Refractory/recurrent vasospasm was observed in 17.4 %, yielding a 10.1 % retreatment rate. Notably, only 35.3 % of vessels undergoing inadequate angioplasty demonstrated improvement at follow-up. Angioplasty targeting distal MCA (adjusted OR, 0.10) or BA-V4 (aOR, 0.10), and inadequate angioplasty (aOR, 0.03) were unfavorable predictors for sustained improvement. Efficacy outcomes were similar between balloon and Comaneci/stentriever in a matched subgroup analysis. CONCLUSION: Angioplasty, when achieving residual narrowing < 50 %, demonstrated sustained improvement for vasospasm. Novel devices may exhibit comparable efficacy to balloon angioplasty for selected segments.

Perioperative blood transfusion management in surgical resection of intracranial meningiomas: A meta-analysis.

Background: Gross total resection (GTR) of intracranial meningiomas is curative in most cases. However, perioperative blood transfusions may be necessary for complex skull bases and/or high-grade meningiomas. Guidelines for blood transfusions during intracranial meningioma surgery remain unclear. This scoping review aims to delineate the main characteristics of patients who underwent intracranial meningioma surgery, the prevalence of the selected patients who required blood transfusions, and common causes for transfusion. Methods: A scoping review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses-Extension for Scoping Reviews guidelines to include studies reporting eligibility, protocols, and potential complications related to blood transfusion within the perioperative management of intracranial meningiomas. Results: A total of 33 articles encompassing 3009 meningioma patients were included in the study. The most common symptom was headache (18%), and the most frequent type of meningioma was World Health Organization grade-1 meningothelial (50.4%). The lateral supraorbital approach was the most common surgical corridor (59.1%) in skull base meningiomas, and most patients underwent GTR (69%). Blood transfusion was required for 20% of patients, with a mean estimated intraoperative blood loss of 703 mL (ranging from 200 mL to 2000 mL). The main indications for blood transfusion in meningioma surgery were intraoperative blood loss (86%) and preoperative anemia (7.3%). Conclusion: This scoping found that 20% of the included patients required blood transfusion. It also points out that several factors could influence the necessity for a transfusion, encompassing surgical blood loss, pre-existing anemia, and the surgery's length. This scoping review may provide surgeons with a potential guide to inform their decision-making process regarding blood transfusions during meningioma surgeries.

Indications, operative techniques, and outcomes of occipital artery-vertebral artery bypass: an institutional series.

PURPOSE: Posterior circulation cerebral bypasses often show higher risks and lower patency. Only few reports discussed occipital artery (OA)-vertebral artery (VA) bypasses. We present our illustrative cases to address current gaps in the literature on OA-VA bypass. METHODS: A single-center retrospective review was conducted to include all institutional cases of OA-VA bypass, discussing the technique and outcomes. RESULTS: Four institutional cases undergoing a total of 5 bypasses were evaluated, including 3 males and 1 female, with median age of 65 years (range, 62-73). All patients had vertebrobasilar insufficiency (VBI) with recurrent strokes/TIAs due to intracranial atherosclerosis, leading to unilateral VA stenosis with contralateral occlusion (1, 25%), bilateral VA stenosis (1, 25%) or occlusion (1, 25%). Medical management included aspirin for all cases (100%), with clopidogrel in 3 (75%). Surgery was performed through a far lateral approach, connecting the OA to the VA-3 segment, with no inter-positional graft. One patient underwent contralateral OA-VA bypass 6 months after the prior surgery due to worsening of the contralateral VA stenosis. Bypass patency was confirmed in all cases with post-operative angiography. All patients had clinical improvement, with one case of wound dehiscence managed conservatively. All patients were alive at last follow-up (median 7.0 months; range: 1.5-18). CONCLUSION: OA-VA bypass is a challenging yet effective strategy in selected patients with VBI. Current literature lacks unique definitions of surgical indications and techniques, which we addressed in our series. Surgical education should focus on expanding the microsurgery anatomy knowledge.

Middle Meningeal Artery Embolization for "Trial-Ineligible" Chronic Subdural Hematomas.

BACKGROUND AND OBJECTIVES: The benefit of middle meningeal artery embolization (MMAE) in the treatment of chronic subdural hematoma (CSDH) has been recently demonstrated in a series of clinical trials. Whether MMAE benefits "trial-ineligible" patients remains elusive. We thus sought to explore the potential benefit of MMAE in neurologically stable (modified Rankin Scale ≤3) patients with "trial-ineligible" CSDHs because of large size: Thickness >15 mm and/or midline shift ≥5 mm. METHODS: A prospectively maintained database was reviewed to identify trial-ineligible CSDHs undergoing standalone MMAE. Surgical rescue rate, hematoma resolution, and neurological deterioration after hematoma progression were evaluated and compared with trial-eligible counterparts. Effect sizes were adjusted for demographic, clinical, and radiological features using multivariable regression. RESULTS: Of 150 standalone MMAE procedures, 92 (61%) were performed in "trial-ineligible" cases: 41% with CSDH thickness >15 mm, 21% with midline shift ≥5 mm, and 38% with both. The surgical rescue rate was 7.6% in the trial-ineligible cohort. Over a median follow-up of 62.5 days, 88.9% cases achieved satisfactory hematoma resolution (≥50% in thickness); 76% had satisfactory resolution at 90-day follow-up. Antithrombotic resumption was a risk factor for surgical rescue (adjusted odds ratio 9.64 [95% CI, 1.33-69.74]; P = .02). Surgical rescue and hematoma resolution did not significantly differ between trial-ineligible and trial-eligible cohorts (P = .87 for surgical rescue rate and P = .85 for hematoma resolution rate). CONCLUSION: This study emphasizes the considerable prevalence of potentially "trial-ineligible" patients with CSDHs because of large size that may still benefit from standalone MMAE.

Microsurgery of Cerebral Arteriovenous Malformations in a Resource-Limited Setting: The First Case-Series from Iraq.

BACKGROUND: Cerebral arteriovenous malformations (AVMs) can lead to significant morbidity and are particularly challenging to manage in resource-limited settings where endovascular treatment modalities are unaffordable for most patients. OBJECTIVE: To describe the first case series of AVM from Iraq with an analysis of the related clinicoradiologic characteristics, operative features, and outcomes. METHODS: A single-center database from October 2018 to December 2022 was reviewed to analyze the characteristics of cerebral AVMs who underwent surgical treatment in Baghdad, Iraq. We collected patient demographics, clinical, radiologic, operative, and the follow-up combined outcome results (modified Rankin Scale score and the presence of AVM remnants). RESULTS: Of the 54 AVM patients treated with microsurgery, the majority of lesions have Spetzler-Martin grade of 3 (31.5%), followed by grade 1 (29.6%). The parietal lobe was the most common location of AVM in 25.9% of the cases, and the temporal location had better outcomes. The mean duration of surgery was 8.5 hours, ranging from 3 to 14 hours, with 20.3% of cases having undergone preoperative stereotactic radiosurgery, and just one patient received preoperative embolization. Good combined outcome (modified Rankin Scale 0-2 and no AVM remnant) was associated with lower SM grades (P=0.003); location in the nondominant hemisphere (P=0.036), and noneloquent regions (P=0.006); absence of deep venous drainage (P=0.042) and no intraoperative brain swelling (P=0.004). The mortality rate in our series was 5.5%. CONCLUSIONS: Good clinicoradiologic outcomes can be achieved through microsurgery in a setting where endovascular treatment is inaccessible to patients due to limited resources.

Intracranial aneurysms and abducent nerve palsy.

Background: Cranial nerve (CN) palsy may manifest as an initial presentation of intracranial aneurysms or due to the treatment. The literature reveals a paucity of studies addressing the involvement of the 6th CN in the presentation of cerebral aneurysms. Methods: Clinical patient data, aneurysmal characteristics, and CN 6th palsy outcome were retrospectively reviewed and analyzed. Results: Out of 1311 cases analyzed, a total of 12 cases were identified as having CN 6th palsy at the presentation. Eight out of the 12 were found in the unruptured aneurysm in the cavernous segment of the internal carotid artery (ICA). The other four cases of CN 6th palsy were found in association with ruptured aneurysms located exclusively at the posterior inferior cerebellar artery (PICA). For the full functional recovery of the CN 6th palsy, there was 50% documented full recovery in the eight cases of the unruptured cavernous ICA aneurysm. On the other hand, all four patients with ruptured PICA aneurysms have a full recovery of CN 6th palsy. The duration for recovery for CN palsy ranges from 1 to 5 months. Conclusion: The association between intracranial aneurysms and CN 6th palsy at presentation may suggest distinct patterns related to aneurysmal location and size. The abducent nerve palsy can be linked to unruptured cavernous ICA and ruptured PICA aneurysms. The recovery of CN 6th palsy may be influenced by aneurysm size, rupture status, location, and treatment modality.

Medications and "Risk" of Aneurysm Rupture Based on Presentation: Setting the Record Straight.

OBJECTIVE: Studies assessing aneurysm rupture "risk" based on comparative retrospective analyses of medications taken on presentation may be subject to presentation bias. Are patients with ruptured aneurysms simply less likely to be taking medications than those with unruptured aneurysms? METHODS: A retrospective chart review was conducted among patients with treated aneurysms from June 2016 to July 2023. A step-wise comparison of demographics, clinical characteristics (rupture status), and medications taken upon presentation was performed between ruptured and unruptured cases. RESULTS: One thousand three hundred eleven patients with intracranial aneurysms were included. The majority of patients presenting with ruptured aneurysms took no medications (68%), in contrast to 22% with unruptured aneurysms (P < 0.001). The majority of patients with unruptured aneurysms took 2-5 medications (51%), in contrast to 15% of patients with ruptured aneurysms taking 2-5 medications (P < 0.001). Twelve percent of patients with unruptured aneurysms took more than 5 medications, while only 1% with ruptured aneurysms did (P < 0.001). Thirty-five different medications were associated with unruptured presentation, including all evaluated antiplatelet agents, anti-hypertensives, antacids, pulmonary inhalers, and psychiatric medications (P < 0.05); no medications were associated with rupture on presentation. CONCLUSIONS: One cannot derive conclusions about medications and "risk" of rupture based on analyses at the time of presentation. This study identifies 35 different medications that were statistically significant and associated with an unruptured presentation; it is doubtful that each is "protective" against aneurysm rupture.

A guide to interpreting systematic reviews and meta-analyses in neurosurgery and surgery.

INTRODUCTION: Systematic reviews (SRs) and meta-analyses (MAs) are methods of data analysis used to synthesize information presented in multiple publications on the same topic. A thorough understanding of the steps involved in conducting this type of research and approaches to data analysis is critical for appropriate understanding, interpretation, and application of the findings of these reviews. METHODS: We reviewed reference texts in clinical neuroepidemiology, neurostatistics and research methods and other previously related articles on meta-analyses (MAs) in surgery. Based on existing theories and models and our cumulative years of expertise in conducting MAs, we have synthesized and presented a detailed pragmatic approach to interpreting MAs in Neurosurgery. RESULTS: Herein we have briefly defined SRs sand MAs and related terminologies, succinctly outlined the essential steps to conduct and critically appraise SRs and MAs. A practical approach to interpreting MAs for neurosurgeons is described in details. Based on summary outcome measures, we have used hypothetical examples to illustrate the Interpretation of the three commonest types of MAs in neurosurgery: MAs of Binary Outcome Measures (Pairwise MAs), MAs of proportions and MAs of Continuous Variables. Furthermore, we have elucidated on the concepts of heterogeneity, modeling, certainty, and bias essential for the robust and transparent interpretation of MAs. The basics for the Interpretation of Forest plots, the preferred graphical display of data in MAs are summarized. Additionally, a condensation of the assessment of the overall quality of methodology and reporting of MA and the applicability of evidence to patient care is presented. CONCLUSION: There is a paucity of pragmatic guides to appraise MAs for surgeons who are non-statisticians. This article serves as a detailed guide for the interpretation of systematic reviews and meta-analyses with examples of applications for clinical neurosurgeons.

Impact of Embolisate Penetration, Type, and Technique on Results After Standalone Middle Meningeal Artery Embolization for Chronic Subdural Hematoma.

BACKGROUND AND OBJECTIVES: Middle meningeal artery embolization (MMAE) has emerged as a promising modality for chronic/subacute subdural hematoma treatment; however, consensus regarding embolization technique and embolisate has not been achieved. We thus sought to compare the efficacy of distinct MMAE techniques and embolisate. METHODS: An institutional registry was reviewed to identify patients undergoing standalone MMAE for symptomatic chronic/subacute subdural hematoma. Surgical rescue rate and time preceding 50% hematoma resolution were evaluated across 3 technical groups: aggressive penetration (AP), nonaggressive penetration with proximal coil embolization (NP-PC), and nonaggressive penetration alone (NP). Effect sizes were adjusted for demographic, neurological and radiological features through multivariable logistic and Cox regression. RESULTS: Among 117 procedures, 33.3% achieved AP, 36.8% had NP-PC, and 29.9% had NP. The rate of surgical rescue was 2.6% after AP, 9.3% for NP-PC, and 11.4% for NP. In patients not undergoing rescue surgery, 82.4% achieved hematoma resolution ≥50% at a median imaging follow-up of 56 days; AP or NP-PC were each statistically significantly associated with enhanced hematoma resolution as compared with NP (P = .02). Similarly, sensitivity analysis within medium-size hematoma and antiplatelet/anticoagulation-at-admission subgroups revealed a superiority of resolution after AP or NP-PC. A unique, comparative secondary analysis of liquid embolisate (Onyx vs n-butyl cyanoacrylate) revealed no impact on rate of surgical rescue or hematoma resolution. CONCLUSION: AP was associated with the lowest rate of surgical rescue, while both AP and NP-PC were associated with improved rates of hematoma resolution.

Anatomical Study of the Supratentorial Extension for the Retrolabyrinthine Presigmoid Approaches.

BACKGROUND: Supratentorial craniotomy represents the upper part of the combined trans-tentorial or the supra-infratentorial presigmoid approach. In this study, we provide qualitative and quantitative analyses for the supratentorial extension of the presigmoid retrolabyrinthine suprameatal approach (PRSA). METHODS: The infratentorial PRSA followed by the supratentorial extension craniotomy with dividing and removal of the tentorial strip were performed on both sides of 5 injected human cadaver heads (n = 10 sides). Quantitative analysis was performed for the surface area gained (surgical accessibility) by adding the supratentorial craniotomy. Qualitative analysis was performed for the parts of the brainstem, cranial nerves, and vascular structures that became accessible by adding the supratentorial craniotomy. The anatomical obstacles encountered in the added operative corridor were analyzed. RESULTS: The supratentorial extension of PRSA provides an increase in surgical accessibility of 102.65% as compared to the PRSA standalone. The mean surface area of the exposed brainstem is 197.98 (standard deviation: 76.222) and 401.209 (standard deviation: 123.96) for the infratentorial and the combined supra-infratentorial presigmoid approach, respectively. Exposure for parts of III, IV, and V cranial nerves is added after the extension, and the surface area of the outer craniotomy defect has increased by 60.32%. Parts of the basilar, anterior inferior cerebellar, and superior cerebellar arteries are accessible after the supratentorial extension. CONCLUSIONS: The supratentorial extension of PRSA allows access to the supra-trigeminal area of the pons and the lower part of the midbrain. Considering this surgical accessibility and exposure significantly assists in planning such complex approaches while targeting central skull base lesions.

Traumatic Cerebral Venous Sinus Thrombosis: Management and Outcomes.

BACKGROUND: Traumatic brain injury (TBI) with skull fractures parallel to or crossing venous sinuses is a recognized risk factor for traumatic cerebral venous sinus thrombosis (tCVST). Despite the recognition of this traumatic pathology in the literature, no consensus regarding management has been achieved. This study aimed to evaluate the impact of tCVST on TBI outcomes and related complications. METHODS: Patients within a prospective registry at a level I trauma center from 2014 to 2023 were reviewed to identify tCVST cases. The impact of tCVST presence on Glasgow Outcome Scale scores at 6 months, 30-day mortality, and hospital length of stay were evaluated in multivariable-adjusted analyses. RESULTS: Among 607 patients with TBI, 61 patients were identified with skull fractures extending to the vicinity of venous sinuses with dedicated venography. Twenty-eight of these 61 patients (44.3%) had tCVST. The majority (96.4%) of tCVST were located in a unilateral transverse or sigmoid sinus. Complete recanalization was observed in 28% of patients on follow-up imaging (7/25 with follow-up imaging). None of the 28 patients suffered attributable venous infarcts or thrombus propagation. In the adjusted analysis, there was no difference in the 30-day mortality or Glasgow Outcome Scale at 6 months between patients with and without tCVST. CONCLUSIONS: Unilateral tCVST follows a benign clinical course without associated increased mortality or morbidity. The management of tCVST should be distinct as compared to spontaneous CVST, likely without the need for anticoagulation.

Developmental Venous Anomalies.

Developmental venous anomalies (DVAs) are the most common vascular malformation detected on intracranial cross-sectional imaging. They are generally benign lesions thought to drain normal parenchyma. Spontaneous hemorrhages attributed to DVAs are rare and should be ascribed to associated cerebral cavernous malformations, flow-related shunts, or venous outflow obstruction. Contrast-enhanced MRI, susceptibility-weighted imaging, and high-field MRI are ideal tools for visualizing vessel connectivity and associated lesions. DVAs are not generally considered targets for treatment. Preservation of DVAs is an established practice in the microsurgical or radiosurgical treatment of associated lesions.

Neurosurgery and Social Media: A Bibliometric Analysis of Scientific Production from 2004 to 2023.

BACKGROUND: Neurosurgery is a rapidly advancing surgical specialty. Social media has significantly impacted the landscape of advancements in the field of neurosurgery. Research on the subject of neurosurgery and social media plays a vital role in combating disability and mortality due to neurological diseases, especially in trauma-affected individuals by increasing cooperation and sharing of clinical experiences between neurosurgeons via social media. This study aimed to evaluate the global neurosurgery and social media research performance from 2004 to 2023. METHODS: All the data for neurosurgery and social media-related research publications from 2004 to 2023 were extracted from the Web of Science database and a comprehensive analysis was performed on the R-bibliometrix package. RESULTS: An increasing number of publications with an annual growth rate of 22.04% was observed, with >91% of total articles published in the last decade. The United States, the United Kingdom, Italy, France, Canada, and India made up of more than 67% of the global contribution. Out of 1449 authors, Chaurasia B was the most productive with 14 publications and the most globally cited document was JEAN WC, 2020 with 117 citations. The University of Cambridge was the leading institutional affiliation. World Neurosurgery was the most productive with >60 articles. CONCLUSIONS: Exploring neurosurgery on social media enhances global collaboration, utilizing dynamic platforms for real-time knowledge exchange and holds immense potential for the field's global advancement.

Mapping the circle of Trolard: A holistic view of its role in neurosurgical practice, anatomical perspectives and clinical applications.

Introduction: An anatomical structure that resembles the circle of Willis, the circle of Trolard is generated in the basal cistern and travels around the midbrain in a roundabout manner, passing adjacent to the lateral side of the cerebral peduncle. Research question: The primary objective of this article is to provide neurosurgeons with a comprehensive understanding of Trolard's circle, emphasizing its anatomical features and clinical significance. Material and methods: A comprehensive evaluation of the available literature pertaining to the venous circle of Trolard was conducted by conducting searches in the PubMed, Web of Science, and Scopus databases. In the present overview, the terminologies "venous circle of Trolard," "basal venous circle," and "basal vein of Rosenthal" were employed. Results: Upon doing a comprehensive examination of the existing literature and primary sources pertaining to the venous circle of Trolard, it was discovered that an only six studies had been conducted on this particular subject matter. We made observations regarding the anatomical characteristics of the subject and engaged in a discussion regarding their prospective applications and importance within the context of neurosurgical procedures. Discussion and conclusion: The scarcity of research on these structures is attributed to the challenges associated in studying them in vivo. Through directing focus towards these structures, our aim is to stimulate further investigation into their potential involvement in a range of neurological and neurosurgical disorders.