Incidence, Pathophysiology, and Prevention Strategies for Cerebral Venous Complications after Neurologic Surgery: A Systematic Review of the Literature.

BACKGROUND: Complications arising from cerebral venous occlusion/sacrifice during neurosurgical procedures have received comparatively less attention in the neurosurgical literature. Consequently, cerebral venous complications are not given due recognition, even though most practicing neurosurgeons would agree that they are not uncommon. We present a review of complications arising from venous sacrifice/occlusion during neurosurgery and discuss strategies described in the literature to prevent such occurrences. METHODS: We conducted a systematic review of the literature to provide a synopsis of the current evidence regarding cerebral venous injury after a neurosurgical procedure. The objectives of this review were to assess the incidence of venous injuries after a neurosurgical procedure with their clinical outcome and to evaluate current strategies and technical advances for their prevention. Complications related to dural venous sinuses were not considered in this review. RESULTS: Twenty-six relevant articles were identified and reviewed. Complications from cerebral venous occlusion/sacrifice are being increasingly recognized, and venous preservation strategies are being promoted in the neurosurgical literature. Based on our review of literature, the incidence of venous injury can range from 2.6% to 30%. We discuss the pathophysiology after venous injury and factors affecting outcome after cerebral venous injury. An overview of surgical techniques described to prevent or manage venous injury during neurosurgical procedures is presented. CONCLUSIONS: The unpredictable response of the brain to venous injury causes catastrophic complications in a few patients. To avoid these complications, meticulous venous preservation should be a goal in all neurosurgical procedures. Increased recognition of cerebral venous complications over the last 2 decades has resulted in the increasing recognition among neurosurgeons that venous preservation is an essential tenet of neurosurgery.

Safety profile of superior petrosal vein (the vein of Dandy) sacrifice in neurosurgical procedures: a systematic review.

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.

Preoperative diffusion tensor imaging-fiber tracking for facial nerve identification in vestibular schwannoma: a systematic review on its evolution and current status with a pooled data analysis of surgical concordance rates.

OBJECTIVE Total tumor excision with the preservation of neurological function and quality of life is the goal of modern-day vestibular schwannoma (VS) surgery. Postoperative facial nerve (FN) paralysis is a devastating complication of VS surgery. Determining the course of the FN in relation to a VS preoperatively is invaluable to the neurosurgeon and is likely to enhance surgical safety with respect to FN function. Diffusion tensor imaging-fiber tracking (DTI-FT) technology is slowly gaining traction as a viable tool for preoperative FN visualization in patients with VS. METHODS A systematic review of the literature in the PubMed, Cochrane Library, and Web of Science databases was performed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and those studies that preoperatively localized the FN in relation to a VS using the DTI-FT technique and verified those preoperative FN tracking results by using microscopic observation and electrophysiological monitoring during microsurgery were included. A pooled analysis of studies was performed to calculate the surgical concordance rate (accuracy) of DTI-FT technology for FN localization. RESULTS Fourteen studies included 234 VS patients (male/female ratio 1:1.4, age range 17-75 years) who had undergone preoperative DTI-FT for FN identification. The mean tumor size among the studies ranged from 29 to 41.3 mm. Preoperative DTI-FT could not visualize the FN tract in 8 patients (3.4%) and its findings could not be verified in 3 patients (1.2%), were verified but discordant in 18 patients (7.6%), and were verified and concordant in 205 patients (87.1%). CONCLUSIONS Preoperative DTI-FT for FN identification is a useful adjunct in the surgical planning for large VSs (> 2.5 cm). A pooled analysis showed that DTI-FT successfully identifies the complete FN course in 96.6% of VSs (226 of 234 cases) and that FN identification by DTI-FT is accurate in 90.6% of cases (205 of 226 cases). Larger studies with DTI-FT-integrated neuronavigation are required to look at the direct benefit offered by this specific technique in preserving postoperative FN function.

Primary calvarial angiosarcoma: A case report and review of the literature.

BACKGROUND: Angiosarcomas are high-grade endothelial tumors remarkable for their rarity and malignant behavior. Primary calvarial angiosarcoma is an extremely rare entity and its behavior usually sets it apart from other angiosarcoma types. We highlight the successful management of cranial angiosarcoma using a multidisciplinary approach. CASE DESCRIPTION: We present a 16-year-old male who was first noted to have a right-sided parietal cranial mass that was biopsied in 2008. Pathology was initially thought to be Kaposiform hemangioendothelioma. The patient subsequently underwent chemotherapy with vincristine. The patient did well until early 2010, when he suffered a right-sided intraparenchymal intratumoral hemorrhage. At this time, the original pathologic diagnosis was revisited and the diagnosis was upgraded to an angiosarcoma. The patient underwent a second round of chemotherapy using vincristine, cyclophosphamide, and actinomycin. The tumor continued to progress despite this treatment and he developed extensive skull deformity. At this point more definitive surgical intervention was reconsidered. Preoperative embolization of the mass was performed followed by aggressive surgical resection of the bony disease. The patient tolerated the procedure well and was discharged 6 days postoperatively without any new deficits. The patient is currently in the process of completing radiation therapy to entire tumor bed. He has clinically done well with no neurologic deterioration and has demonstrated long-term survival (>3 years). CONCLUSION: With the combined efforts of pediatric oncology, radiation oncology, interventional neuroradiology, and neurosurgery, a survival of greater than 3 years is possible with this aggressive pathology.