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Rationale and Objectives: The purpose of this study was to determine the association between hemispheric synchrony in venous outflow at baseline and tissue fate after mechanical thrombectomy (MT) for acute ischemic stroke (AIS)., Materials and Methods: A two-center retrospective analysis involving AIS patients who underwent MT was performed. The four cortical veins of interest include the superficial middle cerebral vein (SMCV), sphenoparietal sinus (SS), vein of Labbé (VOL), and vein of Trolard (VOT). Baseline computed tomography perfusion data were used to compare the following outflow parameters between the hemispheres: first filling time (△FFT), time to peak (△TTP) and total filling time (△TFT). Synchronous venous outflow was defined as △FFT = 0. Multivariable regression analyses were performed to evaluate the association of venous outflow synchrony with penumbral salvage, infarct growth, and intracranial hemorrhage (ICH) after MT., Results: A total of 151 patients (71.4 ± 13.2 years, 65.6% women) were evaluated. Patients with synchronous SMCV outflow demonstrated significantly greater penumbral salvage (41.3 mL vs. 33.1 mL, P = 0.005) and lower infarct growth (9.0 mL vs. 14.4 mL, P = 0.015) compared to those with delayed SMCV outflow. Higher △FFT SMCV (β = -1.44, P = 0.013) and △TTP SMCV (β = -0.996, P = 0.003) significantly associated with lower penumbral salvage, while higher △FFT SMCV significantly associated with larger infarct growth (β = 1.09, P = 0.005) and increased risk of ICH (odds ratio [OR] = 1.519, P = 0.047)., Conclusion: Synchronous SMCV outflow is an independent predictor of favorable tissue outcome and low ICH risk, and thereby carries the potential as an auxiliary radiological marker aiding the treatment planning of AIS patients., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Association of University Radiologists. Published by Elsevier Inc. All rights reserved.)

In the transsylvian (TS) approach, as characterized by clipping surgery, the presurgical visualization of the superficial middle cerebral vein (SMCV) can help change the surgical approach to ensure safe microsurgery. Nevertheless, identifying preoperatively the venous structures that are involved in this approach is difficult. In this study, we investigated the venous structures that are involved in the TS approach using three-dimensional (3D) rotational venography (3D-RV) and evaluated the effectiveness of this method for presurgical simulation. Patients who underwent 3D-RV between August 2018 and June 2020 were involved in this retrospective study. The 3D-RV and partial maximum intensity projection images with a thickness of 5 mm were computationally reconstructed. The venous structures were subdivided into the following three portions according to the anatomic location: superficial, intermediate, and basal portions. In the superficial portion, predominant frontosylvian veins were observed on 31 (41%) sides, predominant temporosylvian veins on seven (9%) sides, and equivalent fronto- and temporosylvian veins on 28 (37%) sides. The veins in the intermediate (deep middle cerebral and uncal veins) and basal portions (frontobasal bridging veins) emptied into the SMCV on 57 (75%) and 34 (45%) sides, respectively. The 3D-RV images were highly representative of the venous structures observed during microsurgery. In this study, 3D-RV was utilized to capture the details of the venous structures from the superficial to the deep portions. Presurgical simulation of the venous structures that are involved in the TS approach using 3D-RV may increase the safety of microsurgical approaches.

Background and Purpose: Cortical venous outflow has emerged as a robust measure of collateral blood flow in acute ischemic stroke. The addition of deep venous drainage to this assessment may provide valuable information to further guide the treatment of these patients., Materials and Methods: We performed a multicenter retrospective cohort study of patients with acute ischemic stroke treated by thrombectomy between January 2013 and January 2021. The internal cerebral veins were scored on a scale of 0-2. This metric was combined with existing cortical vein opacification scores to create a comprehensive venous outflow score from 0 to 8 and stratify patients as having favorable-versus-unfavorable comprehensive venous outflow. Outcome analyses were primarily conducted using the Mann-Whitney U and χ 2 tests., Results: Six hundred seventy-eight patients met the inclusion criteria. Three hundred fifteen were stratified as having favorable comprehensive venous outflow (mean age, 73 years; range, 62-81 years; 170 men), and 363, as having unfavorable comprehensive venous outflow (mean age, 77 years; range, 67-85 years; 154 men). There were significantly higher rates of functional independence (mRS 0-2; 194/296 versus 37/352, 66% versus 11%, P  < .001) and excellent reperfusion (TICI 2c/3; 166/313 versus 142/358, 53% versus 40%, P  < .001) in patients with favorable comprehensive venous outflow. There was a significant increase in the association of mRS with the comprehensive venous outflow score compared with the cortical vein opacification score (-0.74 versus -0.67, P = .006)., Conclusions: A favorable comprehensive venous profile is strongly associated with functional independence and excellent postthrombectomy reperfusion. Future studies should focus on patients with venous outflow status that is discrepant with the eventual outcome., (© 2023 by American Journal of Neuroradiology.)

The preoperative assessment of cerebral veins is important to avoid unexpected cerebral venous infarction in the neurosurgical setting. However, information is particularly limited regarding deep Sylvian veins, which occasionally disturb surgical procedures for cerebral anterior circulation aneurysms. The predictability of detecting deep Sylvian veins and their tributaries using a modern multimodal fusion image was aimed to be evaluated. Moreover, 51 patients who underwent microsurgery for unruptured cerebral aneurysms with Sylvian fissure dissection were retrospectively reviewed. The visualization of the four components of the deep Sylvian veins in conventional computed tomography (CT) venography and multimodal fusion images was evaluated. To compare the detection accuracy among these radiological images, the sensitivity and specificity for the detection of each of the four venous structures were calculated in comparison with those of intraoperative inspections. The kappa coefficients were also measured and the inter-rater agreement for each venous structure in each radiological image was examined. In all veins, the multimodal fusion image exhibited a high detection rate without statistical difference from intraoperative inspections (P = 1.0). However, CT venography exhibited a low detection rate with a significant difference from intraoperative inspections in the common vertical trunk (P = 0.006) and attached vein (P = 0.008). The kappa coefficients of the fusion image ranged from 0.73 to 0.91 and were superior to those of CT venography for all venous structures. This is the first report to indicate the usefulness of a multimodal fusion image in evaluating deep Sylvian veins, especially for the detection of nontypical, relatively small veins with large individual variability.

(1) Background: The inferior anastomotic vein of Labbé (LV) courses on the temporal lobe, from the sylvian fissure towards the tentorium cerebelli and finishes at the transverse sinus (TS). The importance of the LV topography is related to skull base neurosurgical approaches. Based on the hypothesis of the existence of as yet unidentified anatomical possibilities of the LV, we aimed through this research to document the superficial venous topographic patterns at the lateral and inferior surfaces of the temporal lobe. (2) Methods: A retrospective cohort of 50 computed tomography angiograms (CTAs) of 32 males and 18 females was documented. (3) Results: Absent (type 0) LVs were found in 6% of cases. Anterior (temporal, squamosal-petrosal-mastoid, type 1) LVs were found in 12% of cases. LVs with a posterior, temporoparietal course (type 2) were found to be bilateral in 46% of cases and unilateral in 36% of cases. Type 3 LVs (posterior, parietooccipital) were found to be bilateral in 8% and unilateral in 32% of cases. In 24% of cases, duplicate LVs were found that were either complete or incomplete. A quadruplicate LV was found in a male case. On 78 sides, the LV drained either into a tentorial sinus or into the TS. (4) Conclusions: The anatomy of the vein of Labbé is variable in terms of its course, the number of veins and the modality of drainage; thus, it should determine personalized neurosurgical and interventional approaches. A new classification of the anatomical variations of Labbé's vein, as detected on the CTAs, is proposed here (types 0-3).

Competing Interests: None

In this third review article on the endovascular management of intracranial dural AVFs, we discuss transvenous embolization approaches. Transvenous embolization is increasingly popular and now the first-line approach for ventral dural AVFs involving the cavernous sinus and hypoglossal canal. In addition, transvenous embolization is increasingly used in lateral epidural dural AVFs in high-risk locations such as the petrous and ethmoid regions. The advantage of transvenous embolization in these locations is the ability to retrogradely embolize the draining vein and fistula while reducing the risk of ischemic cranial neuropathy or brain parenchymal infarction commonly feared from a transarterial approach. By means of coils ± ethylene-vinyl alcohol copolymer, transvenous embolization can achieve angiographic cure rates of 80%-90% in ventral locations. Potential complications include transient cranial neuropathy, neurologic deterioration due to venous outflow obstruction, and perforation while navigating pial veins. Transvenous embolization should be considered when dural AVFs arise in proximity to the vasa nervosum or extracranial-intracranial anastomoses., (© 2022 by American Journal of Neuroradiology.)

Trigeminal neuralgia (TN) is often caused by various vein forms. Herein, we report two cases of vein-related TN. In the first case, the vein of the cerebellopontine fissure (VCPF), along with the thickened surrounding arachnoid, clung to the trigeminal nerve. As the perfusion range of this vein was expected to be wide and its injury might cause extensive venous infarction, the anchor between the trigeminal nerve and the vein was carefully dissected and the vein was successfully transposed. In the second case, the involvement of the vein of the middle cerebellar peduncle (VMCP), which penetrates the nerve bundle of the trigeminal nerve, was suspected. Because vein transposition was impossible, the vein was transected at the nerve penetration site after confirming that there was sufficient collateral venous outflow. The superior petrosal vein and its tributaries are the primary causative veins of vein-related TN, and their contact patterns are infinite. Moreover, their perfusion range and the presence or absence of collateral venous outflow vary from case to case. Therefore, it is necessary to judge the perfusion range as well as collateral venous outflow based on preoperative images and intraoperative findings and to determine the appropriate treatment method for each case.

The superficial middle cerebral vein (SMCV) is one of the main factors that can impede a wide opening of the sylvian fissure. To reveal the most efficient SMCV dissection for a wide operative field while preserving the veins in the trans-sylvian approach, we retrospectively investigated the SMCVs through intraoperative video images. We characterized the SMCV as composed of the frontosylvian trunk (FST; receiving frontosylvian veins [FSVs] or parietosylvian veins [PSVs]), the temporosylvian trunk (TST; receiving temporosylvian veins [TSVs]), and the superficial middle cerebral common trunk (SMCCT; receiving both FSV/PSV and TSV), and classified the SMCVs of the 116 patients into 5 types based on the morphological classification of the SMCV. Type A SMCV (60.4%) with the SMCCT anastomosed to the frontal side had few bridging veins (BVs) between the SMCCT and the temporal side during dissection. Type B (7.8%) had the SMCCT with no anastomoses to the frontal side. In Type C (17.2%) consisting of the FST and TST and Type D (12.9%) with a merging of the vein of Trolard and Labbé posteriorly and the SMCVs dividing into the FST and the TST again proximally, there were few BVs between the FST and the TST during dissection. Finally, in Type E (1.7%) showing an undeveloped SMCV, there were no BVs between the frontal and the temporal lobes. Postoperative venous infarction occurred in 2.6%. Morphological classification of the SMCV can inform appropriate dissection line to create a wide operative field while preserving the veins in the trans-sylvian approach.

Venous sinus stenting is an accepted and minimally invasive treatment for idiopathic intracranial hypertension associated with significant venous sinus stenosis. There is inherent difficulty in navigating past the region of venous stenosis in order to safely deliver and deploy a stent. We have developed the "Cobra" technique, which allows for the safe and efficient navigation past regions of high-grade venous sinus stenosis.

Aim: To report the surgical outcomes in patients with trigeminal neuralgia (TN) who underwent microvascular decompression (MVD) with superior petrosal vein sacrification., Material and Methods: Data from 63 patients, whose information was obtained from a group of 113 patients who underwent surgery from 2008 to 2018, were reviewed retrospectively by the first author who was not part of the surgical team, and the pain conditions were evaluated objectively., Results: Following surgery, pain relief occurred in 84% of patients during the early postoperative period and in 69.8% of patients during long-term follow-up. The major offending vessel was the superior cerebellar artery., Conclusion: MVD surgery, in particular for patients with typical pain, is one of the most effective treatment strategies for TN. Superior petrosal vein sacrification is a safe method that helps neurosurgeons to visualise the surgical area and perform a better work-up. Neurosurgeons should not be afraid to carry out superior petrosal vein sacrification.

In this study, we used 45 adult cadaveric cerebral hemispheres to investigate the anatomical classification of the superficial middle cerebral vein (SMCV) based on the number of stems, course, and anastomosis at the distal portion. We classified the SMCVs into five types based on embryological concept. Type A (18 cases, 40.0%) is that the frontosylvian veins (FSVs) merge with the vein of Trolard (VT) and the vein of Labbé (VL) at the distal portion of the sylvian fissure. Type B (5 cases, 11.1%) is that the temporosylvian veins (TSVs) merge with the VT and the VL at the distal portion. Type C (13 cases, 28.9%) is that no vein merge with the VT and the VL at the distal portion. The VT merges with the SMCV from the FSV and the VL merges with the SMCV from the TSV. They course along the sylvian fissure and merge at the proximal portion. In Type D (eight cases: 17.8%), the VT and the VL merge at the distal portion, and the SMCV from the FSV and the SMCV from the TSV join their confluence without merging. Type E (one case, 2.2%) show an undeveloped SMCV. Formation rate of intravenous anastomoses or bridging veins(BVs) at the distal portion between the frontosylvian trunk (FST) and the temporosylvian trunk (TST), between the FST and the temporal lobe, and between the TST and the frontal lobe was very low, because these formation may be difficult to occur during the embryological process in which the SMCV is formed from the telencephalic vein.

Posterior fossa dural arteriovenous fistulas (dAVFs) are rare vascular malformations. They carry a significant risk of hemorrhage if associated with cortical venous reflux. A 70-year-old man presented with right-sided medullary hemorrhage with pronounced Wallenberg syndrome. Angiography demonstrated right jugular foramen dAVF with direct brainstem venous reflux (Cognard IV). It was fed from multiple branches of the external carotid artery and the vertebral artery, and draining into the ascending pontomesencephalic vein. Primary two-stage transarterial embolization was performed with near-total occlusion of the fistula to prevent it from rebleeding in the acute phase. Because of the patient's significant neurological deficit, the surgery was deferred to later and if the DAVF showed further progression. Follow-up angiography 8 months later demonstrated obvious recurrence and progression of the fistula from adjacent feeders. In the meantime, the patient had a remarkable recovery from the Wallenberg symptoms. To achieve complete occlusion of the fistula, a right far lateral approach was chosen with complete disconnection of the fistula. Postoperative angiography confirmed complete occlusion of the fistula, and the patient remained intact from the procedure.The video can be found here: https://youtu.be/DJvpa8G4olc.

Cerebral vein thrombosis is a severe complication of inflammatory bowel disease, can cause non-specific symptoms and hence lead to delay in diagnosis. We report the case of an adolescent with inflammatory bowel disease who developed extensive cerebral vein thrombosis requiring a ventriculoperitoneal shunt. Diagnosis was markedly delayed due to repeated misinterpretation of clinical signs and laboratory findings and the lack of reconsidering the working diagnosis despite the involvement of several medical subspecialties. The patient does not suffer from any neurological impairment. This case report highlights the need for clinicians to maintain vigilance for complications of chronic disease and encourages to cast doubt on the working diagnosis constantly., Competing Interests: Competing interests: None declared., (© BMJ Publishing Group Limited 2019. No commercial re-use. See rights and permissions. Published by BMJ.)

Background and Purpose- The role of recanalization of the occluded dural sinus or vein in the outcome of patients with cerebral venous thrombosis (CVT) is not established. We aimed to systematically review, in patients with CVT, (1) the recanalization rate and its association with (2) clinical outcome and (3) CVT recurrence. Methods- Systematic search in MEDLINE (Medical Literature Analysis and Retrieval System Online), Cochrane Library, and clinicaltrials.gov (inception to September 2017). We considered cohort studies reporting the recanalization rate in adult patients with CVT treated with anticoagulation. Reported rates of venous recanalization at the last follow-up, functional outcome defined using the modified Rankin scale at last follow-up dichotomized for favorable (0-1) and unfavorable (2-6) outcome, and recurrence rate of CVT according to recanalization status were extracted independently by 2 authors. Meta-analyses of proportions were performed using Freeman-Tukey double arcsine transformation. Functional outcomes according to the recanalization status were compared using meta-analysis and ordinal logistic regression. We conducted sensitivity analyses for time to assessment of recanalization and study quality. Results- Four hundred sixty-eight studies were identified, and 19 studies were included. (1) We found report of 694 patients with recanalization in the follow-up among 818 cases of CVT. The overall pooled proportion of patients achieving recanalization was 85% (95% confidence interval, 80-89; I 2 =58%). In studies with higher methodological quality, the recanalization rate was 77% (95% confidence interval, 70-82; I 2 =0%). (2) There was a significant increase in the chance of favorable outcome (modified Rankin scale, 0-1) in patients with recanalization with a pooled odds ratio of 3.3 (95% confidence interval, 1.2-8.9; I 2 =32%) in the random effects meta-analysis and a common odds ratio of 3.3 (95% confidence interval, 1.7-6.3) in the ordinal logistic regression. (3) Data on CVT recurrence according to recanalization was scarce. Conclusions- The overall rate of recanalization in patients receiving anticoagulation was 85%, but exclusion of severe patients from follow-up imaging is a plausible source of bias. Lack of venous recanalization was associated with worse clinical outcome.

OBJECTIVE Walter E. Dandy described for the first time the anatomical course of the superior petrosal vein (SPV) and its significance during surgery for trigeminal neuralgia. The patient's safety after sacrifice of this vein is a challenging question, with conflicting views in current literature. The aim of this systematic review was to analyze the current surgical considerations regarding Dandy's vein, as well as provide a concise review of the complications after its obliteration. METHODS A systematic review was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A thorough literature search was conducted on PubMed, Web of Science, and the Cochrane database; articles were selected systematically based on the PRISMA protocol and reviewed completely, and then relevant data were summarized and discussed. RESULTS A total of 35 publications pertaining to the SPV were included and reviewed. Although certain studies report almost negligible complications of SPV sectioning, there are reports demonstrating the deleterious effects of SPV obliteration when achieving adequate exposure in surgical pathologies like trigeminal neuralgia, vestibular schwannoma, and petroclival meningioma. The incidence of complications after SPV sacrifice (32/50 cases in the authors' series) is 2/32 (6.2%), and that reported in various case series varies from 0.01% to 31%. It includes hemorrhagic and nonhemorrhagic venous infarction of the cerebellum, sigmoid thrombosis, cerebellar hemorrhage, midbrain and pontine infarct, intracerebral hematoma, cerebellar and brainstem edema, acute hydrocephalus, peduncular hallucinosis, hearing loss, facial nerve palsy, coma, and even death. In many studies, the difference in incidence of complications between the SPV-sacrificed group and the SPV-preserved group was significant. CONCLUSIONS The preservation of Dandy's vein is a neurosurgical dilemma. Literature review and experiences from large series suggest that obliterating the vein of Dandy while approaching the superior cerebellopontine angle corridor may be associated with negligible complications. However, the counterview cannot be neglected in light of some series showing an up to 30% complication rate from SPV sacrifice. This review provides the insight that although the incidence of complications due to SPV obliteration is low, they can happen, and the sequelae might be worse than the natural history of the existing pathology. Therefore, SPV preservation should be attempted to optimize patient outcome.

OBJECTIVE The best management of veins encountered during the neurosurgical approach is still a matter of debate. Even if venous sacrifice were to lead to devastating consequences, under certain circumstances, it might prove to be desirable, enlarging the surgical field or increasing the extent of resection in tumor surgery. In this study, the authors present a large series of patients with vascular or oncological entities, in which they used indocyanine green videoangiography (ICG-VA) with FLOW 800 analysis to study the patient-specific venous flow characteristics and the management workflow in cases in which a venous sacrifice was necessary. METHODS Between May 2011 and December 2017, 1972 patients were admitted to the authors' division for tumor and/or neurovascular surgery. They retrospectively reviewed all cases in which ICG-VA and FLOW 800 were used intraoperatively with a specific target in the venous angiographic phase or for the management of venous sacrifice, and whose surgical videos and FLOW 800 analysis were available. RESULTS A total of 296 ICG-VA and FLOW 800 studies were performed intraoperatively. In all cases, the venous structures were clearly identifiable and were described according to the flow direction and speed. The authors therefore defined different patterns of presentation: arterialized veins, thrombosed veins, fast-draining veins with anterograde flow, slow-draining veins with anterograde flow, and slow-draining veins with retrograde flow. In 16 cases we also performed a temporary clipping test to predict the effect of the venous sacrifice by the identification of potential collateral circulation. CONCLUSIONS ICG-VA and FLOW 800 analysis can provide complete and real-time intraoperative information regarding patient-specific venous drainage pattern and can guide the decision-making process regarding venous sacrifice, with a possible impact on reduction of surgical complications.

The relevance of the cerebral venous system is often underestimated during neurosurgical procedures. Damage to this draining system can have catastrophic implications for the patient. Surgical decision-making and planning must consider each component of the venous compartment, from the medullary draining vein to the dural sinuses and extracranial veins. Intraoperative ultrasound (ioUS) permits the real-time study of venous compartments using different modalities, thus allowing complete characterization of their anatomical and functional features. The B-mode (brightness mode) offers a high-resolution anatomical representation of veins and their relationships with lesions. Doppler modalities (color, power, spectral) allow the study of blood flow and identification of vessels to distinguish their functional characteristics. Contrast-enhanced US allows one to perform real-time angiosonography showing both the functional and the anatomical aspects of vessels. In this technical report, the authors demonstrate the different applications of multimodal ioUS in neurosurgery for identifying the anatomical and functional characteristics of the venous compartment. They discuss the general principles and technical nuances of ioUS and analyze their potential implications for the study of various venous districts during neurosurgical procedures.

This paper is a narrative review of extraaxial developmental venous anomalies (eDVAs) of the brain involving dural venous flow or sinuses: persistent embryonic sinuses, sinus pericranii, enlarged emissary veins, and venous varices or aneurysmal malformations. The article highlights the natural history, anatomy, embryology, imaging, clinical implications, and neurosurgical significance of these lesions, which the authors believe represent a continuum, with different entities characterized by distinct embryopathologic features. The indications and surgical management options are discussed for these individual intracranial pathologies with relevant illustrations, and a novel classification is proposed for persistent falcine sinus (PFS). The role of neurointervention and/or microsurgery in specific cases such as sinus pericranii and enlarged emissary veins of the skull is highlighted. A better understanding of the pathophysiology and developmental anatomy of these lesions can reduce treatment morbidity and mortality. Some patients, including those with vein of Galen malformations (VOGMs), can present with the added systemic morbidity of a high-output cardiac failure. Although VOGM is the most studied and classified of the above-mentioned eDVAs, the authors believe that grouping the former with the other venous anomalies/abnormalities listed above would enable the clinician to convey the exact morphophysiological configuration of these lesions, predict their natural history with respect to evolving venous hypertension or stroke, and extrapolate invaluable insights from VOGM treatment to the treatment of other eDVAs. In recent years, many of these symptomatic venous malformations have been treated with endovascular interventions, although these techniques are still being refined. The authors highlight the broad concept of eDVAs and hope that this work will serve as a basis for future studies investigating the role of evolving focal venous hypertension/global intracranial hypertension and possibilities of fetal surgical intervention in these cases.

Rationale: Foreign bodies in the vasculature usually cause numerous problems for clinical physicians. Physician experience with diagnosing and treating non-iatrogenic foreign body migration in the venous system is insufficient., Patient Concerns: Here, we reported a 41-year-old male who had a foreign body in his left forearm following a work-related injury., Diagnoses: X-ray films indicated a 3-mm high-density shadow in the superficial soft tissue of the left forearm. During the operation, the foreign body was imaged by a C-arm fluoroscope to provide a more accurate location., Interventions: The foreign body was removed completely following a microsuture of the cephalic vein., Outcomes: The procedure was uneventful, and the patient remained asymptomatic after 6 months of clinical follow-up., Lessons: This case indicated that the foreign body in the superficial tissue needed to be accurately diagnosed and located. X-ray and C-arm fluoroscope imaging should be combined with the patient's medical history to ensure sufficient preoperative preparation.

Indocyanine green (ICG) emits fluorescence in the far-red domain under light excitation. ICG video angiography (ICG-VA) has been established as a useful method to evaluate blood flow in the operative field. We report the usefulness of ICG-VA for Sylvian fissure dissection in patients with subarachnoid hemorrhage (SAH). Subjects comprised 7 patients who underwent ICG-VA before opening the Sylvian fissure during neck clipping for ruptured cerebral aneurysm. We observed contrasted Sylvian veins before opening the Sylvian fissure using surgical microscopes. This procedure was termed "Sylvian ICG". We observed ICG fluorescence quickly in all cases. Sylvian veins that appeared unclear in the standard microscopic operative field covered with subarachnoid hemorrhage were extremely clearly depicted. These Sylvian ICG findings were helpful in identifying entry points and the dissecting course of the Sylvian fissure. At the time of clipping, no residual fluorescence from Sylvian ICG was present, and aneurysm clipping was not impeded. Sylvian ICG for SAH patients is a novel technique to facilitate dissection of the Sylvian fissure. We believe that this technique will contribute to improved safety of clipping surgery for ruptured aneurysms.

Background and Purpose: Although current guidelines advocate pretreatment with intravenous thrombolysis (IVT) in all eligible patients with acute ischemic stroke with large-vessel occlusion before mechanical thrombectomy, there are observational data questioning the efficacy of this approach. One of the main arguments in favor of IVT pretreatment is the potential for tissue-type plasminogen activator-induced successful reperfusion (SR) before the onset of endovascular procedure., Methods: We performed a systematic review and meta-analysis of randomized controlled clinical trials and observational cohorts providing rates of SR with IVT in patients with large-vessel occlusion before the initiation of mechanical thrombectomy. We also performed subgroup analyses according to study type (randomized controlled clinical trials versus observational) and according to the inclusion per protocol of patients with tandem (intracranial/extracranial) occlusions., Results: We identified 13 eligible studies (7 randomized controlled clinical trials and 6 observational cohorts), including 1561 patients with acute ischemic stroke (median National Institutes of Health Stroke Scale score, 17) with large-vessel occlusion. SR following IVT and before mechanical thrombectomy was documented in 11% (95% confidence interval, 7%-16%), with no difference among cohorts derived from randomized controlled clinical trials and observational studies. There was significant heterogeneity across included studies both in the overall analysis and among subgroups (I 2 >84%; P for Cochran Q, <0.001). Higher tissue-type plasminogen activator-induced SR rates were documented in studies reporting the exclusion of tandem occlusions (17%; 95% confidence interval, 11%-23%) compared with the rest (7%; 95% confidence interval, 4%-11%; P for subgroup differences, 0.003)., Conclusions: Pretreatment with systemic thrombolysis in patients with large-vessel occlusion eligible for mechanical thrombectomy results in SR in 1 of 10 cases, negating the need for additional endovascular reperfusion. Tandem occlusions seem to be the least responsive to IVT pretreatment., (© 2017 American Heart Association, Inc.)

Aim: Surgery for intracranial complex vascular malformations can be quite exigent and involves considerable preoperative planning. Here, we present the advantages of using three-dimensional (3D) printed models as a preoperative investigational modality., Material and Methods: 3D printed models were made from thin-slice computed tomography (CT) angiography scans of 6 patients with arteriovenous malformations over an18-month period from August 2015 to December 2016. The locations of the arteriovenous malformations were in the Sylvian fissure in 1 patient, posterior frontal region in 2 patients, subfrontal region in 1 patient, and parietal region in 2 patients. The CT angiography was performed on a 64-slice CT scanner. Thin-slice axial CT sections were acquired and a volume file was created of the arteriovenous malformation and the required skull bones. The file was then transferred to the 3D printer for creating the model., Results: The model depicted the precise nature of the compactness and location of the nidus in relationship to the skull. It was possible to clearly delineate the course, size, and number of feeding vessels and draining veins. The model made identification of the normal and abnormal vessels easier and assisted in the preparation and conduct of surgery. The model was made to scale and was placed beside the surgeon during the operation. The limitation of current technology was that the exact differentiation of arteries and veins by color coding was not possible., Conclusion: 3D printed models can be helpful in getting information regarding the architecture and character of the arteriovenous malformation. The models are cost-effective and easy to build.

Background: The superior sagittal sinus and the draining cerebral veins are often encountered during the surgery for parasagittal and falx meningiomas and during the interhemisperic transcallosal approaches. A knowledge about the variations from the normally described anatomy helps in anticipating and avoiding problems related to these structures during surgery., Aim: The normal variations in the disposition of the superior sagittal sinus and the number and direction of the draining veins in the Indian population have been studied., Settings and Design: This is an anatomical study in the fresh cadavers., Materials and Methods: Sixty fresh cadavers were examined in the autopsy theatre of the Forensic Medicine Department of the Hospital between March 2011 and February 2013., Statistical Analysis Used: Epi-Info, MS-Excel, and the Statistical Package for the Social Sciences (SPSS) were used for data analysis., Results: The position of the superior sagittal sinus was variable and was up to within 1cm on either side of the sagittal suture. The origin of the superior sagittal sinus varied from the level of foramen caecum to a little posterior from the foramen caecum. The total length of the superior sagittal sagitttal sinus varied from 321 mm to 357 mm (average length 338.77mm); vertical compartments of the sinus were found in three-fourth of the cases studied. Tributaries were found in the herringbone pattern and varied from 13 to 19 on the right and 14 to 19 on the left. The Rolandic vein was the largest draining vein in most of the cases. The superior sagittal sinus drained predominantly to the right transverse sinus in three-fourth of the cases studied. The position of the torcula was variable; often towards the right side and at a higher level. The central sulcus was 49.93 mm posterior to the coronal suture and 130.78 mm anterior to the lambdoid suture., Conclusions: This is the first study of its kind in Indian population studying the anatomical variations in the anatomy of the superior sagittal sinus that may have a significant bearing on the neurosurgical approaches adopted.

Understanding the altered physiology following cerebrospinal fluid (CSF) diversion in the setting of adult hydrocephalus is important for optimizing patient care and avoiding complications. There is mounting evidence that the cerebral venous system plays a major role in intracranial pressure (ICP) dynamics especially when one takes into account the effects of postural changes, atmospheric pressure, and gravity on the craniospinal axis as a whole. An evolved mechanism acting at the cortical bridging veins, known as the "Starling resistor," prevents overdrainage of cranial venous blood with upright positioning. This protective mechanism can become nonfunctional after CSF diversion, which can result in posture-related cerebral venous overdrainage through the cranial venous outflow tracts, leading to pathological states. This review article summarizes the relevant anatomical and physiological bases of the relationship between the craniospinal venous and CSF compartments and surveys complications that may be explained by the cerebral venous overdrainage phenomenon. It is hoped that this article adds a new dimension to our therapeutic methods, stimulates further research into this field, and ultimately improves our care of these patients.

The authors demonstrate an interhemispheric transchoroidal approach for third ventricular teratoma resection. Interhemispheric dissection exposed the corpus callosum at a length of about 2 cm. A callosotomy was made to enter into the right lateral ventricle. After septal vein ligation, dissection was made of the space between the right fornix and right internal cerebral vein (ICV); thus bilateral fornix and left ICV would be retracted to the left; right choroid plexus, right ICV to the right. By this transchoroidal approach, the foramen of Monro was extended posteriorly, providing enough of a surgical corridor to resect a posteriorly located third ventricular tumor. The video can be found here: https://youtu.be/gIzPiH3zx&#95;o .

This video demonstrates surgical techniques of the occipital transtentorial approach to a pineal region tumor without using a fixed brain retractor, which may cause functional impairment or even tissue injury to the occipital visual cortex. There are several ways to facilitate retractorless surgery through this approach. A lateral-semiprone positioning of the patient can induce gravity retraction. The brain is relaxed by draining CSF fluid through lumbar drainage or lateral ventricular tap in the case of obstructive hydrocephalus. Dynamic retraction with handheld instruments after extensive dissection of the deep venous system, including basal veins, can provide a sufficient working space. The video can be found here: https://youtu.be/kQvEHiNcRow .

Intracranial dural arteriovenous fistulas (dAVF) with cervical perimedullary drainage, Cognard V, are a surgically challenging rare entity. In this video we show the disconnection of a right tentorial Cognard V dAVF, done through a subtemporal transtentorial approach with the application of indocyanine green video angiography. A 47-year-old man presented with severe tetraparesis. Only partial embolization was possible. An osteoplastic frontotemporal craniotomy was performed to obtain a wide view along with CSF release to safely mobilize the temporal lobe. Neuronavigation was used to detect the fistula and indocyanine to detect the tentorial afferent arteries and to confirm final disconnection. The video can be found here: https://youtu.be/Yr8tAiiHNXU .

Spinal pial arteriovenous fistulas (SPAVFs) are rare lesions that present more frequently in young patients. Lesions located on radiculo-pial arteries without involvement of the anterior spinal artery are even rarer. SPAVFs may present with mass effect, venous congestion or hemorrhage. Most often, treatment is performed either by surgery or endovascularly with fluid embolic material. Use of microcoils has not been reported for this condition.We present two cases of radiculo-pial high-flow SPAVFs in two patients in their early 30 s. One patient presented with abrupt headache without proof of hemorrhage and the other one with trigeminal neuralgia resulting from dilated posterior fossa draining veins remote from the fistula. Both patients were successfully treated with endovascular shunt closure using microcoils with resolution of symptoms and disappearance of the dilated veins at follow-up.With recent advances in microcatheter technology, distal navigation and microcoil embolization offers another option for these cases that may be safer than fluid embolic material., (© The Author(s) 2015.)

Background: We present two rare cases of pineal-region meningiomas. These tumors are the first reported cases of dura-unrelated meningiomas originating from the arachnoid membrane over the vein of Galen (AMG)., Case Description: In Case 1, a 37-year-old woman presented with a progressing headache. Magnetic resonance imaging (MRI) showed a large tumor in the pineal region, displacing the vein of Galen upward. Angiography disclosed occlusion of the vein of Galen, with deep venous flow draining through the veins on the right medial surface of the occipital lobe to the superior sagittal sinus. In Case 2, a 67-year-old man presented with dizziness. MRI demonstrated a large mass in the pineal region, displacing the vein of Galen inferiorly. Angiography disclosed occlusion of the vein of Galen, with deep venous flow draining through the collateral venous channel into the transverse sinus. Both tumors were totally excised (Simpson Grade III for Case 1, Grade I for Case 2) via a left occipital transtentorial approach. No dural attachment was recognized in either case, but the tumor in Case 1 was firmly adherent to the inferior portion of the AMG, while that in Case 2 was attached to the superior portion of the AMG, but remained dissectible., Conclusions: We reported two cases of pineal-region meningiomas originating from the arachnoid membrane over the vein of Galen, resulting in meningioma without dural attachment. These tumors can be totally resected by careful dissection of the tumor from the arachnoid membrane surrounding the vein of Galen.

Clipping of a posterior projecting large posterior communicating aneurysm via transsylvian anterior temporal approach is presented. To expose and clip this large aneurysm, retraction of the temporal lobe is required via the conventional pterional approach. In this video, we demonstrate microsurgical techniques as to how to dissect and mobilize the sylvian veins as well as a bridging vein to the sphenoparietal sinus, and the middle cerebral artery branches to the frontal lobe side. After the microsurgical dissection, a wide anteriolateral temporal space is obtained without significant temporal lobe retraction. The aneurysm was completely obliterated via this approach. The video can be found here: http://youtu.be/vU9Nxm7Yn-A.

Acute thrombosis of cerebral veins and sinuses (ATCVS) is a multifactorial disease with grave consequences. Because of its rare occurrence there are no proven treatment guidelines. Sixteen patients with ATCVS were treated. The final diagnosis was confirmed by digital subtraction angiography. Sinus catheterization was performed via transfemoral venous access. Treatment included mechanical manipulation of thrombi and thrombolytic therapy. A regression of clinical symptoms with a concomitant decrease of intracranial hypertension was achieved in all patients. Long-term results were studied in eight patients: none presented clinical signs of intracranial hypertension. Endovascular transvenous recanalization is an effective treatment for acute thrombosis of cerebral veins and sinuses. Along with the local thrombolysis, significant potential in the treatment of this complex pathology lies in the transvenous endovascular techniques of mechanical thrombus extraction, especially in patients with intracranial hemorrhage for whom the use of thrombolytic agents is restricted.

Object: Pediatric patients with sickle cell anemia (SCA) carry a significant risk of developing moyamoya syndrome (MMS) and brain ischemia. The authors sought to review the safety and efficacy of pial synangiosis in the treatment of MMS in children with SCA by performing a comprehensive review of all previously reported cases in the literature., Methods: The authors retrospectively reviewed the clinical and radiographic records in 17 pediatric patients with SCA treated at the Morgan Stanley Children's Hospital of New York (MSCHONY) who developed radiological evidence of MMS and underwent pial synangiosis between 1996 and 2012. The authors then added any additional reported cases of pial synangiosis for this population in the literature for a combined analysis of clinical and radiographic outcomes., Results: The combined data consisted of 48 pial synangiosis procedures performed in 30 patients. Of these, 27 patients (90%) presented with seizure, stroke, or transient ischemic attack, whereas 3 (10%) were referred after transcranial Doppler screening. At the time of surgery, the median age was 12 years. Thirteen patients (43%) suffered an ischemic stroke while on chronic transfusion therapy. Long-term follow-up imaging (MR angiography or catheter angiography) at a mean of 25 months postoperatively was available in 39 (81%) treated hemispheres. In 34 (87%) of those hemispheres there were demonstrable collateral vessels on imaging. There were 4 neurological events in 1590 cumulative months of follow-up, or 1 event per 33 patient-years. In the patients in whom complete data were available (MSCHONY series, n = 17), the postoperative stroke rate was reduced more than 6-fold from the preoperative rate (p = 0.0003)., Conclusions: Pial synangiosis in patients with SCA, MMS, and brain ischemia appears to be a safe and effective treatment option. Transcranial Doppler and/or MRI screening in asymptomatic patients with SCA is recommended for the diagnosis of MMS.

Background: The clinical profiles of cerebellar cavernous malformations (CCMs) with and without associated developmental venous anomalies (DVAs) are not well known. The aims of this study were to analyze the clinical and radiological characteristics of CCMs and to assess the various therapeutic strategies., Methods: A consecutive series of 41 patients with identified CCMs were retrospectively reviewed. Of these, 11 patients (26.8%) were found to have associated DVAs. We compared the clinical profile of the two groups of patients (CCMs with and without DVAs). The CCMs with DVAs cases underwent radical resection of the CCMs, and the distal radicles of the DVAs that directly drain from the CCMs were coagulated and dissected at the length of the CCMs., Results: There were no statistically significant differences between the two groups with regard to age, sex, location and size of lesions, multiplicity, and surgical prognosis. The patients with CCMs with DVAs did not experience any brain swelling or hemorrhagic tendency intraoperatively. The postoperative course was uneventful for all of the 36 surgical patients with the exception of two of the patients with CCMs with associated DVAs, who suffered from serious cerebellar edema, and one of these two patients underwent an emergency suboccipital decompression craniotomy. With the exception of three patients who were lost to follow-up (mean, 22.3 months), all of the CCMs patients exhibited good long-term prognosis (modified Rankin scale values of 0-2) and no reoccurrence., Conclusions: It is not rare that associated DVAs occur in CCMs. The total removal of the CCM combined with the coagulation and dissection of the distal radicles of DVA at the length of the associated CCM may result in good long-term prognosis in patients.

The endovascular treatment of spontaneous dural cavernous sinus fistula (DAVF) can be accomplished by arterial approach, just with symptoms relief, or by numerous venous approaches through the inferior petrosal sinus, ophthalmic vein, anterior or posterior intercavernous sinus and facial vein. Our case suggests the approach to the cavernous sinus via the foramen ovale and emissary veins puncture as an alternative when there is no possibility of venous approach conventionally described. A 76-year-old woman presented with right conjunctival hyperemia, exophthalmos, intraocular pressure increasing and visual deficits in a period of six months. Angiographic diagnosis of spontaneous DAVF isolated from the cavernous sinus, Barrow Type C, with exclusive venous drainage through the superior ophthalmic vein. Endovascular treatment was performed under general anesthesia. Attempts to approach the cavernous sinus through the inferior petrosal sinus ipsilateral and contralateral intercavernous, facial vein and pterygoid plexus, as well as by dissection and direct puncture of the superior ophthalmic vein were not possible. An approach to the cavernous sinus was performed by puncturing the foramen ovale, catheterization of the emissary vein of the foramen ovale with occlusion of the fistula with microcoils. There was a symptomatic regression with gradual normalization of intraocular pressure, exophthalmos and conjunctival hyperemia in three months. The approach to the cavernous sinus through the foramen ovale and catheterization of the emissary cranial skull base vein is an exception and should be considered in cases of spontaneous and isolated DAVF not accessible by a conventional approach.

Aim: The objectives were to find the incidence and topography of the occipital emissary foramina in skulls of South Indian Region., Material and Methods: In the present study, 78 dried adult human skulls were examined. They were analyzed for the gross incidence and position of the occipital emissary foramen. The observations were made in the squamous part of the occipital bone from the posterior margin of the foramen magnum to the external occipital protuberance., Results: From our observations, the occipital emissary foramen was present in 11 (14.1%) skulls. Left sided foramen was observed in 5 cases (6.4%), right-sided foramen in 4 (5.1%) and the median foramen was seen in 2 (2.6%) of the cases., Conclusion: The occipital emissary vein is present in a small percentage (14.1%) of cases. It was also demonstrated that its location is variable as to left, right or midline. Its location was closer to the foramen magnum than to the external occipital protuberance in all the specimens. The morphology of this subject is important to the neurosurgeons and plastic surgeons. The knowledge is of importance in suboccipital craniotomies as this foramen transmits the occipital emissary vein and will keep awareness among the surgeons to avoid the excessive bleeding.

The trans-sylvian approach is one of the most frequently employed neurosurgical procedures, but it is difficult for medical students to understand the approach stereoscopically. A three-dimensional model equipped with an arachnoid membrane and sylvian vein was developed which can be repeatedly used to simulate surgery for the education of medical students and residents in the trans-sylvian approach. The model was prepared using existing models of the skull bone, brain, and cerebral artery. Polyvinylidene chloride film, commonly used as plastic wrap for food, was adopted for the arachnoid membrane, and wetted water-insoluble tissue paper for the arachnoid trabeculae. The sylvian vein was prepared by ligating woolen yarn with cotton lace thread at several sites. Students and residents performed the trans-sylvian approach under a microscope, and answered a questionnaire survey. Using this model, simulation of division of the arachnoid membrane and arachnoid trabeculae, and dissection of the sylvian vein was possible. In the questionnaire, the subjects answered 8 questions concerning understanding of the stereoscopic anatomy of the sylvian fissure, usefulness of the simulation, and interest in neurosurgical operation using the following ratings: yes, very much; yes; somewhat; not very much; or not at all. All items rated as 'yes, very much' and 'yes' accounted for more than 70% of answers. This model was useful for medical students to learn the trans-sylvian approach. In addition, repeated practice is possible using cheap materials, which is advantageous for an educational model.

A 41-year-old woman presented with progressive hemianopsia caused by compression of the lateral geniculate body by the dilated basal vein draining a contralateral frontal arteriovenous malformation (AVM). Magnetic resonance (MR) imaging revealed left frontal AVM and right lateral geniculate body compression due to the dilated basal vein. Emergent presurgical transarterial embolization and surgical removal were performed. Left hemianopsia completely recovered 3 months after surgery and MR imaging indicated improvement of the compression of the lateral geniculate body. Direct mechanical compression of the enlarged drainage vein is one of the causes of homonymous hemianopsia. Early surgical treatment is recommended to obtain a rapid recovery.

An 85-year-old woman presented with a dural arteriovenous fistula of the superior petrosal sinus manifesting as venous infarction of the cerebellum. Magnetic resonance imaging and angiography revealed right cerebellar swelling, venous engorgement, and an arteriovenous fistula in the superior petrosal sinus. Our initial attempt to obliterate the lesion through a transvenous endovascular approach failed, so we successfully treated the fistula via surgical interruption of the superior petrosal vein through a small suboccipital craniotomy. Careful examination of the pattern of venous drainage is important to determine surgical indications. This case indicates that minimally invasive open surgery can be effective even in an elderly patient.

Developmental venous anomalies (DVAs) represent a rare cause of intraparenchymal hemorrhage. This case demonstrates an unusual DVA associated with venous hypertension, arteriovenous shunting, and a ruptured transitional aneurysm. The authors describe the first use of embolization as a treatment method for an unstable ruptured transitional aneurysm associated with a DVA. This 33-year-old man suffered acute onset of headache, gait ataxia, and left hemiparesis. Computed tomography brain scans demonstrated a deep paramedian right frontal intraparenchymal hemorrhage. No cavernous malformation was apparent on MR imaging. Diagnostic angiography revealed arteriovenous shunting from the right anterior and middle cerebral arteries to a large DVA with an associated arteriovenous fistula, with a 3-mm aneurysm in the transition from pericallosal artery to the collecting vein. Both surgical and endovascular treatment options were considered. The patient underwent repeat angiography on hospital Day 7, at which time the aneurysm had increased to 5 mm, and endovascular treatment was selected. Acrylic occlusion of the aneurysm was performed and confirmed angiographically. The patient's neurological symptoms resolved throughout the hospital stay, and he remains symptom free in the 10 months since treatment. Developmental venous anomalies are not usually associated with arteriovenous shunting and aneurysms as a source of intraparenchymal hemorrhage. Endovascular occlusion of the aneurysm without blockage of physiologically necessary venous structures is a possible method of treatment for this complex mixed vascular lesion, and has proven safe and effective in this patient. To the authors' knowledge, this is the first presentation of this situation in the literature.

A 29-year-old man developed a delayed postoperative extradural hematoma after the craniotomy to treat recurrent malignant glioma and hydrocephalus. The patient became alert on the day after the operation. Computed tomography (CT) 12 hours after the operation showed no intracranial hematoma and the subgaleal drainage catheter was removed 18 hours after the operation. The patient complained of headache and went into a coma 2 hours after removal of the drain. CT demonstrated massive acute extradural hematoma with marked midline shift. Emergency craniotomy revealed that the source of the hematoma was an injured scalp artery along the route of the drainage catheter. He died of acute brain edema 9 days later. Hemostasis should be confirmed at insertion and removal of the drainage catheter.

A seven-month-old infant presented with a generalized seizure. The radiological evaluation revealed a large arteriovenous fistula in the left sylvian region. The fistula connected the left middle cerebral artery and the vein of Trolard. A giant varix was present at the venous end. The child underwent craniotomy, complete disconnection of the fistula and excision of the varix. Except for recurrent seizures, which were eventually controlled on anticonvulsants, the child's neurological development has been good on long-term follow-up of three years. Pial arteriovenous fistulae are rare intracranial vascular malformations. Though significant operative risks exist, they can be successfully managed surgically with good long-term prognosis.

Cerebral venous sinus thrombosis (CVST) usually is taken care of by medical management or neuro-interventional vascular techniques. Some cases of CVST may take a malignant course if the intracranial pressure increases excessively. This increase in pressure is because of oedema in brain tissue due to impediment in venous return and/or intracerebral haemorrhage. Neurosurgical experience has shown remarkable recovery in these moribund patients if appropriate surgical intervention is done within reasonable time. Emergent decompressive craniotomy or other neurosurgical interventions are the only appropriate treatment in these malignant forms of CVST to prevent mortality and severe morbidity.

The management of cavernous malformations of the brain is markedly influenced by the location of the lesions themselves. In the last decade, resection of cavernomas arising in the dominant insular lobe has been deemed safe only with the guidance of neuronavigation. Most navigation equipment, however, shares some minor drawbacks, including costs, longer operating time, and a variable loss of accuracy due to intraoperative brain shift. In this paper the authors present the case of a left dominant insular cavernoma that was successfully removed using a novel form of navigation that they call magnetic resonance imaging-based corticotopography. This technique, which is unaffected by the brain shift phenomenon, provided a simple and inexpensive alternative to standard neuronavigation. Selected cases of subcortical brain lesions could be conveniently approached using the same technique.

Object: Although there is general agreement on the methods of treatment for symptomatic supratentorial cerebral cavernous malformations (CMs) located in noneloquent areas, some controversy exists regarding the management of cerebral CMs that are asymptomatic and/or located in eloquent or deep areas. Moreover, recent advances in genetic findings could influence both standard clinical management and the follow-up strategy in affected individuals. Thus, the objective of this study was to develop, based on the authors' experience and a literature review, a management algorithm to deal with supratentorial cerebral CMs., Methods: The authors retrospectively reviewed the clinical data related to 118 patients who underwent surgery for symptomatic supratentorial cerebral CMs at their institution. Twenty-eight of 118 patients harbored multiple lesions, and nine of these 28 patients had a clinically positive familial history. Genetic investigations were performed in 89 patients (75%)., Conclusions: Surgery for supratentorial cerebral CMs in noneloquent locations is safe and curative. In cerebral CMs located in deep and eloquent areas and with symptoms including progressive neurological deficits, evidence of hemorrhage, and uncontrolled seizures, surgical treatment according to an integrated plan based on frameless stereotactic guidance and functional magnetic resonance imaging is recommended and results in acceptably low morbidity. The data support the need for long-term imaging follow up in all patients, careful preoperative vascular studies to detect associated venous anomalies, and the importance of genetic mutational analysis. The DNA screening protocol will change the care of family members of patients with familial forms of cerebral CMs, because affected asymptomatic family members may benefit by early detection of lesions. At the same time, the exclusion of family members who are not carriers of the mutation as members of the population at risk reduces the economic and psychological burden of clinical and instrumental monitoring.

Object: The aim of this study was to analyze cerebellar cavernous malformations (CMs) with respect to epidemiological, clinical, radiological, and therapeutic aspects., Methods: Between 1984 and 2004, 100 patients were surgically treated for intracranial CMs at the Division of Neurosurgery of Federal University of Sao Paulo. The authors reviewed the records of 10 patients whose lesions were located in the cerebellum. There were four male and six female patients (ratio 1:1.5) whose ages ranged from 14 to 45 years (mean age 33 years). Clinical presentation was sudden or acute in all cases, and neuroimaging examinations performed in all patients demonstrated signs of bleeding. The mean size of the malformations was 4.6 cm, and in all but one patient the lesions were totally removed without complications. After a mean follow-up period of 70 months, all patients were considered to be in good or excellent clinical condition., Conclusions: Cerebellar CMs should be analyzed separately from other posterior fossa CMs. These lesions can reach large sizes and cause massive hemorrhages, resulting in acute or sudden presentation. Surgery is a safe and effective option that provides a curative treatment when a complete removal is achieved.