1-Piece Versus 2-Piece Fronto-Temporo-Orbito-Zygomatic Craniotomy: A Narrative Overview of Evolution.

BACKGROUND: The fronto-temporo-orbito-zygomatic (FTOZ) craniotomy is a commonly utilized surgical approach for many complex skull base lesions, especially lesions traversing skull base compartments. This craniotomy has evolved over multiple stages, originating from the classic pterional craniotomy and many variations that have emerged over time. METHODS: Few clinical and anatomic studies have both shaped these craniotomies as well as provided immense information about instances in which they are most useful. We review the origin and history of the one-piece and two-piece fronto-temporo-orbito-zygomatic craniotomy and deliberate their advantages and disadvantages. RESULTS: The FTOZ craniotomy provides access to the orbit as well as to multiple compartments in the cranium (anterior, middle and upper third posterior cranial fossae); thus, offering a multi-corridor approach to complex skull base lesions. The one-piece and two-piece fronto-temporo-orbitozygomatic craniotomies are two particularly notable variations that have stood the test of time. Selection between the two variations is mostly surgeon preference and comfort with the technique; however, there are certain indications that specifically suit each approach. Additionally, a pictorial review has been crafted to clearly illustrate the cuts to be made in both methods. CONCLUSION: Understanding the evolution of this craniotomy and surgical approach provides an insight into accessing complex skull base pathologies with minimal brain retraction via safe and viable corridors.

Retrograde trans-posterior communicating artery rescue balloon angioplasty of incompletely expanded pipeline embolization device: complication management.

BACKGROUND: Pipeline embolization device (PED) deployment is a technically demanding procedure. Incomplete device expansion or deployment is one intra-operative risk, especially in patients with significant vascular tortuosity. CASE DESCRIPTION: We describe the case of a 71-year female with an unruptured left vertebral artery saccular aneurysm. Tortuosity of the arteries proximal to the aneurysm complicated deployment and the proximal end of the PED failed to expand despite several maneuvers. The inadequately expanded PED caused flow limitation in the left vertebral artery and it became imperative to achieve wall apposition of the PED. We salvaged the PED from the left vertebral artery by retrograde trans-right posterior communicating artery balloon angioplasty. CONCLUSIONS: Our case documents the successful application of the rarely used salvage strategy - anterior-to-posterior circulation retrograde rescue balloon angioplasty of an unopened PED.

Microsurgical clipping and endovascular management of unruptured anterior circulation aneurysms: how age, frailty, and comorbidity indexes influence outcomes.

OBJECTIVE: Frailty is one of the important factors in predicting the outcomes of surgery. Many surgical specialties have adopted a frailty assessment in the preoperative period for prognostication; however, there are limited data on the effects of frailty on the outcomes of cerebral aneurysms. The object of this study was to find the effect of frailty on the surgical outcomes of anterior circulation unruptured intracranial aneurysms (UIAs) and compare the frailty index with other comorbidity indexes. METHODS: A retrospective study was performed utilizing the National Inpatient Sample (NIS) database (2016-2018). The Hospital Frailty Risk Score (HFRS) was used to assess frailty. On the basis of the HFRS, the whole cohort was divided into low-risk (0-5), intermediate-risk (> 5 to 15), and high-risk (> 15) frailty groups. The analyzed outcomes were nonhome discharge, complication rate, extended length of stay, and in-hospital mortality. RESULTS: In total, 37,685 patients were included in the analysis, 5820 of whom had undergone open surgical clipping and 31,865 of whom had undergone endovascular management. Mean age was higher in the high-risk frailty group than in the low-risk group for both clipping (63 vs 55.4 years) and coiling (64.6 vs 57.9 years). The complication rate for open surgical clipping in the high-risk frailty group was 56.1% compared to 0.8% in the low-risk group. Similarly, for endovascular management, the complication rate was 60.6% in the high-risk group compared to 0.3% in the low-risk group. Nonhome discharges were more common in the high-risk group than in the low-risk group for both open clipping (87.8% vs 19.7%) and endovascular management (73.1% vs 4.4%). Mean hospital charges for clipping were $341,379 in the high-risk group compared to $116,892 in the low-risk group. Mean hospital charges for coiling were $392,861 in the high-risk frailty group and $125,336 in the low-risk group. Extended length of stay occurred more frequently in the high-risk frailty group than in the low-risk group for both clipping (82.9% vs 10.7%) and coiling (94.2% vs 12.7%). Frailty had higher area under the receiver operating characteristic curve values than those for other comorbidity indexes and age in predicting outcomes. CONCLUSIONS: Frailty affects surgical outcomes significantly and outperforms age and other comorbidity indexes in predicting outcome. It is imperative to include frailty assessment in preoperative planning.

Primary Treatment of Small to Medium (<3 cm) Sporadic Vestibular Schwannomas: A Systematic Review and Meta-Analysis on Hearing Preservation and Tumor Control Rates for Microsurgery versus Radiosurgery.

BACKGROUND: A meta-analysis of patients with sporadic vestibular schwannoma (VS) primarily treated with stereotactic radiosurgery (SRS) or microsurgery (MS) was performed, and hearing preservation outcome (HPO), tumor control (TC), and facial nerve dysfunction (FND) were analyzed. METHODS: A systematic review was conducted (Medline and Scopus database) for the period January 2010-June 2020 with appropriate MeSH. English language articles for small to medium sporadic VS (<3 cm) using SRS or MS as primary treatment modality, with minimum follow-up of 3 years, were included. Studies had to report an acceptable standardized hearing metric. RESULTS: Thirty-two studies met the inclusion criteria: 10 MS; 23 radiosurgery, and 1 comparative study included in both. HPO, at approximately 65 months follow-up, were comparable between MS group (10 studies; 809 patients) and SRS group (23 studies; 1234 patients) (56% vs. 59%; P = 0.1527). TC, at approximately 70 months follow-up, was significantly better in the MS group (9 studies; 1635 patients) versus the SRS group (19 studies; 2260 patients) (98% vs. 92%; P < 0.0001). FND, at approximately 12 months follow-up, was significantly higher in the MS group (8 studies; 1101 patients) versus the SRS group (17 studies; 2285 patients) (10% vs. 2%; P < 0.0001). CONCLUSIONS: MS and SRS are comparable primary treatments for small (<3 cm) sporadic VS with respect to HPO at 5-year follow-up in patients with serviceable hearing at presentation; approximately 50% of patients for both modalities likely lose serviceable hearing by that time point. High TC rates (>90%) were seen with both modalities; MS 98% versus SRS 92%. The posttreatment FND was significantly less with the SRS group (2%) versus the MS group (10%).

Direct thrombectomy versus bridging thrombolysis with mechanical thrombectomy in middle cerebral artery stroke: a real-world analysis through National Inpatient Sample data.

OBJECTIVE: A paradigm shift in the management of acute ischemic stroke (AIS) due to large-vessel occlusion (LVO) occurred after 2015 when 7 randomized controlled trials demonstrated better outcomes using second-generation thrombectomy devices combined with best medical management than did stand-alone intravenous thrombolysis (IVT) with tissue plasminogen activator (tPA). All recently published landmark trials were designed to study the outcome of mechanical thrombectomy (MT); therefore, the majority of the patients enrolled in these trials received intravenous tPA. Currently, initiating IVT before MT is a matter of debate. Recent trials (DIRECT-MT, DEVT) exploring this clinical question showed noninferiority of MT alone compared with the combined treatment. With this uncertainty, the authors aimed to explore real-world data through the latest National Inpatient Sample (NIS) to compare the safety and outcomes of MT alone with bridging IVT and MT in AIS due to LVO in the middle cerebral artery (MCA). METHODS: NIS data from 2017 to 2018 were analyzed to compare the outcomes and safety profiles of patients who underwent MT+IVT with those who underwent MT alone. RESULTS: A total of 2895 patients were included in the final analysis (MT, n = 1669; MT+IVT, n = 1226). The mean National Institutes of Health Stroke Scale score was 16.2 (SD 6.1) in the MT group and 16.6 (SD 5.97) in the MT+IVT group (p = 0.04). With respect to comorbidities, the two groups did not differ in rates of hypertension (p = 0.730), atrial fibrillation/flutter (p = 0.828), and smoking status (p = 0.914). The rate of diabetes mellitus was significantly higher in the MT group (28%) than in the MT+IVT group (22.1%) (p < 0.001). The frequency of intracerebral hemorrhage (ICH) in the MT group was 17.7% (n = 296) and 21.5% (n = 263) in the MT+IVT group (p = 0.012). Intraventricular hemorrhage (p = 0.875), subarachnoid hemorrhage (p = 0.99), and vasospasm (p = 0.976) did not differ significantly between the groups. The primary outcome considered was disability status between the groups; 23.8% of patients in the MT+IVT group had minimal disability versus 18.2% in the MT group (p = 0.001). The risk of progressing to severe disability from minimal disability decreased with the addition of IVT to MT (OR 0.762, 95% CI 0.637-0.912). The adjusted odds ratio for ICH in the MT+IVT group was 1.28 (95% CI 1.043-1.571, p = 0.018) and 2.676 (95% CI 1.259-5.686, p = 0.01) for access-site hemorrhages. CONCLUSIONS: In the analysis of the NIS database, the MT+IVT group had significantly higher rates of minimal disability at the time of hospital discharge versus the MT-alone group, despite a higher rate of ICH. The question of whether to treat patients with MT+IVT rather than MT alone is currently being addressed in ongoing prospective clinical trials (SWIFT-DIRECT [NCT03494920], MR CLEAN-NO IV [ISRCTN80619088], and DIRECT-SAFE [NCT03494920]). The results of these studies will contribute to greater understanding and progressive improvement in outcomes for AIS patients.

Investigating the efficacy of allograft cellular bone matrix for spinal fusion: a systematic review of the literature.

OBJECTIVE: The use of allograft cellular bone matrices (ACBMs) in spinal fusion has expanded rapidly over the last decade. Despite little objective data on its effectiveness, ACBM use has replaced the use of traditional autograft techniques, namely iliac crest bone graft (ICBG), in many centers. METHODS: In accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, a systematic review was conducted of the PubMed, Cochrane Library, Scopus, and Web of Science databases of English-language articles over the time period from January 2001 to December 2020 to objectively assess the effectiveness of ACBMs, with an emphasis on the level of industry involvement in the current body of literature. RESULTS: Limited animal studies (n = 5) demonstrate the efficacy of ACBMs in spinal fusion, with either equivalent or increased rates of fusion compared to autograft. Clinical human studies utilizing ACBMs as bone graft expanders or bone graft substitutes (n = 5 for the cervical spine and n = 8 for the lumbar spine) demonstrate the safety of ACBMs in spinal fusion, but fail to provide conclusive level I, II, or III evidence for its efficacy. Additionally, human studies are plagued with several limiting factors, such as small sample size, lack of prospective design, lack of randomization, absence of standardized assessment of fusion, and presence of industry support/relevant conflict of interest. CONCLUSIONS: There exist very few objective, unbiased human clinical studies demonstrating ACBM effectiveness or superiority in spinal fusion. Impartial, well-designed prospective studies are needed to offer evidence-based best practices to patients in this domain.

Primary Tumors of the Posterior Pituitary Gland: A Systematic Review of the Literature in Light of the New 2017 World Health Organization Classification of Pituitary Tumors.

OBJECTIVE: The rare clinical entity of primary posterior pituitary tumors (PPTs) includes pituicytomas, granular cell tumors, spine cell oncocytomas, and sellar ependymomas. The recent World Health Organization classification of PPTs based on thyroid transcription factor 1 positivity has led to more investigations into the epidemiology, clinical presentation, nature history, histologic features, and operative characteristics of these tumors. The aim of this review is to summarize the characteristics of primary PPTs. METHODS: Our summary involved an in-depth review of the literature on PPTs. Our systematic review was carried out using the PubMed database and PRISMA guidelines. RESULTS: An initial search identified 282 publications. After strict application of the inclusion criteria, we found 16 articles for case series of patients with primary PPT (N > 5), which were included in our table for literature review. An additional 10 articles were review articles on PPTs published in the last 20 years and were used as resource for our systematic review. An extensive analysis was then performed to extract relevant clinical data with respect to the clinical radiologic histopathologic profile of primary PPTs and their treatment outcome. CONCLUSIONS: Primary PPTs are a rare group of pituicyte-derived low-grade nonneuroendocrine neoplasms that arise from the sellar region. The nondescript radiographic findings and subtle endocrine abnormalities also veil their accurate diagnostic prediction. As shown through the narrative as well as the literature review, there is still a lot to be understood about PPTs. A prospective multicenter registry of these rare tumors would benefit both the neurosurgical as well as the endocrinologic knowledge base.

Cerebral Revascularization for Moyamoya Syndrome Associated with Sickle Cell Disease: A Systematic Review of the Literature on the Role of Extracranial-Intracranial Bypass in Treating Neurologic Manifestations of Pediatric Patients with Sickle Cell Disease.

Moyamoya syndrome (MMS) in patients with sickle cell disease (SCD) accentuates the risk of recurrent strokes. Chronic transfusion therapy (CTT) is an excellent option for preventing recurrent strokes in most patients with SCD. In SCD with MMS, CTT may fail as a long-term solution. Cerebral revascularization, in the form of extracranial-intracranial bypass, has been shown to prevent recurrent strokes in this cohort. We review the evolution of this paradigm shift in the management of SCD-associated MMS. A systematic review, adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses protocol, was conducted. Our primary objectives were 1) to study the evolution of cerebral revascularization techniques in management of MMS in SCD and 2) to analyze the impact of neurosurgical intervention in this high-risk population. Four patients with SCD-associated MMS, who underwent indirect cerebral revascularization at our institute were retrospectively reviewed. A summary of 13 articles chronicling the advent and subsequent evolution of cerebral revascularization as a viable treatment strategy for stroke prevention in SCD-associated MMS is presented. The literature review suggests that early detection and surgical intervention (in addition to CTT) could significantly reduce stroke recurrence and improve neurocognitive outcome. Our short series of 4 patients also had a good outcome and no recurrence of strokes postoperatively. The literature emphasizes the use of a traditional standardized protocol for early identification (transcranial Dopplers, selective magnetic resonance angiography, and CTT). Early treatment and screening that involves early magnetic resonance angiography and referral to neurosurgery for revascularization may be considered for this high-risk population.

Comparing the Biomechanical Stability of Cortical Screw Trajectory Versus Standard Pedicle Screw Trajectory for Short- and Long-Segment Posterior Fixation in 3-Column Thoracic Spinal Injury.

BACKGROUND: Information on the performance of posterior fixation with cortical screw (CS) versus pedicle screw (PS) trajectories for stabilizing thoracolumbar burst fractures is limited. Therefore, we sought to analyze stability with CS versus PS in short- and long-segment fixations using a 3-column spinal injury model. METHODS: Nondestructive flexibility tests: (1) intact, (2) intact + short fixation, (3) intact + long fixation, (4) after burst fracture, (5) short fixation + burst fracture, and (6) long fixation + burst fracture using thoracic spine segments (7 CS, 7 PS). RESULTS: With CS, the range of motion (ROM) was significantly greater with short-segment than with long-segment fixation in all directions, with and without burst fracture (P ≤ .008). With PS and burst fracture, ROM was significantly greater with short fixation during lateral bending and axial rotation (P < .006), but not during flexion-extension (P = .10). Groups with CS versus PS were not significantly different after burst fracture during flexion-extension and axial rotation, with short (P ≥ .58) or long fixation (P ≥ .17). During lateral bending, ROM was significantly greater with CS versus PS, without burst fracture (long fixation, P = .02) and with burst fracture (short and long fixation, P ≤ .001). CONCLUSIONS: CS trajectory is a valid alternative to PS trajectory for thoracic spine fixation in 3-column spinal injuries, and long-segment fixation is superior to short-segment fixation with either.

Management of Meningiomas Involving the Major Venous Sinuses: A Single-Institution Experience.

BACKGROUND: In the management of meningiomas invading the major venous sinuses, balance between tumor control and complication prevention is desirable. The aim of this study was to describe an institutional experience in management of meningiomas involving major venous sinuses. METHODS: A retrospective study was carried out over 18 years, between 1999 and 2017, in patients with meningiomas involving major venous sinuses. Clinical features, operative strategy, histology, postoperative complications, adjuvant therapy, and long-term follow-up were studied. RESULTS: The study included 84 patients. Neurologic deficits were seen in 26 (31%) patients at presentation. The recurrence rates in Simpson grade I, II, and III excision were 7.6%, 25%, and 29.4% at a mean follow-up of 45.4 months (range, 1-192 months). No intervention of the involved sinus was done in 64 (76%) cases, venotomy was done in 3 (3.5%) cases, sinus resection without graft was done in 14 (16.6%) cases, and sinus reconstruction with patch was done in 3 (3.5%) cases. There were 53 (67.0%) patients with World Health Organization grade I histology and 25 (31.6%) patients with World Health Organization grade II histology. Fifteen recurrences were treated with Gamma Knife radiosurgery. In univariate analysis using Cox proportional hazards model, World Health Organization grade (P = 0.036, hazard ratio 2.90, 95% confidence interval = 1.07-7.87) and Simpson grade (P = 0.017, hazard ratio 2.90, 95% confidence interval = 1.18-5.29) were found to be significant factors to predict tumor recurrence. CONCLUSIONS: Management of meningiomas involving major venous sinus with microsurgical techniques and adjuvant Gamma Knife radiosurgery achieves a good tumor control rate with an acceptable complication rate.

Timing of Carotid Endarterectomy for Symptomatic Carotid Stenosis: A Snapshot of Current Trends and Systematic Review of Literature on Changing Paradigm towards Early Surgery.

Carotid revascularization has been recommended as the maximally beneficial treatment for stroke prevention in patients with recently symptomatic carotid stenosis (SCS). The appropriate timing for performing carotid endarterectomy (CEA) within the first 14 d after the occurrence of the index event remains controversial. We aim to provide a snapshot of the pertinent current literature related to the timing of CEA for patients with SCS. A systematic review of literature was conducted to study the timing of CEA for SCS. The guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) were followed. A total of 63 articles were identified as relevant to this topic. A summary of 15 articles favoring urgent CEA (within 48 h) for SCS within 48 h of index event and 9 articles not favoring urgent CEA is presented. A consensus is still to be achieved on the ideal timing of CEA for SCS within the 14-d window presently prescribed. The current literature suggests that patients who undergo urgent CEA (within 48 h) after nondisabling stroke as the index event have an increased periprocedural risk as compared to those who had transient ischemic attack (TIA) as the index event. Further prospective studies and clinical trials studying this question with separate groups classified as per the index event are required to shed more light on the subject. The current literature points to a changing paradigm towards early carotid surgery, specifically targeted within 48 h if the index event is TIA, and within 7 d if the index event is stroke.

Retromastoid Approach for Posterior Fossa Skull Base Rosai-Dorfman Disease-A Rare Pathology: 3-Dimensional Operative Video.

Rosai-Dorfman disease, originally described by Juan Rosai and Ronald F. Dorfman, is a rare benign histiocytic proliferative disorder, classically presenting with massive lymphadenopathy and a self-limiting clinical course.1 Isolated intracranial skull base involvement is extremely rare and often resembles meningiomas, schwannomas, or other benign skull base lesions.2 The disease is difficult to diagnose radiographically, and tissue diagnosis with open skull base approaches has significant perioperative risks.2,3 We present the case of a 48-yr-old Caucasian male presenting with progressively worsening headaches, giddiness, hearing difficulty, and diplopia. Magnetic resonance imaging of the brain revealed T1-weighted isointense, T2-weighted hypointense, and contrast-enhancing dural-based lesion in the left cerebellopontine angle. The patient underwent maximally safe resection of the lesion through the retromastoid approach with careful preservation of the lower cranial nerve complex. The intraoperative findings of a variegated and lobulated mass adherent to the skull base, the surgical strategy of safe resection, and eventual good outcome in this patient are depicted in this 3-dimensional video presentation. The majority of patients with skull base Rosai-Dorfman disease reported in literature have had stable or regression of disease (78%) after initial conservative surgical treatment and hence aggressive surgical resection is of unproven efficacy.3 The patient has consented to depiction of his surgical video and intraoperative images in this video manuscript.

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.

A Cost-Effectiveness Analysis of the Integration of Robotic Spine Technology in Spine Surgery.

OBJECTIVE: We investigate the cost-effectiveness of adding robotic technology in spine surgery to an active neurosurgical practice. METHODS: The time of operative procedures, infection rates, revision rates, length of stay, and possible conversion of open to minimally invasive spine surgery (MIS) secondary to robotic image guidance technology were calculated using a combination of institution-specific and national data points. This cost matrix was subsequently applied to 1 year of elective clinical case volume at an academic practice with regard to payor mix, procedural mix, and procedural revenue. RESULTS: A total of 1,985 elective cases were analyzed over a 1-year period; of these, 557 thoracolumbar cases (28%) were analyzed. Fifty-eight (10.4%) were MIS fusions. Independent review determined an additional ~10% cases (50) to be candidates for MIS fusion. Furthermore, 41.4% patients had governmental insurance, while 58.6% had commercial insurance. The weighted average diagnosis-related group reimbursement for thoracolumbar procedures for the hospital system was calculated to be $25,057 for Medicare and $42,096 for commercial insurance. Time savings averaged 3.4 minutes per 1-level MIS procedure with robotic technology, resulting in annual savings of $5,713. Improved pedicle screw accuracy secondary to robotic technology would have resulted in 9.47 revisions being avoided, with cost savings of $314,661. Under appropriate payor mix components, robotic technology would have converted 31 Medicare and 18 commercial patients from open to MIS. This would have resulted in 140 fewer total hospital admission days ($251,860) and avoided 2.3 infections ($36,312). Robotic surgery resulted in immediate conservative savings estimate of $608,546 during a 1-year period at an academic center performing 557 elective thoracolumbar instrumentation cases. CONCLUSION: Application of robotic spine surgery is cost-effective, resulting in lesser revision surgery, lower infection rates, reduced length of stay, and shorter operative time. Further research is warranted, evaluating the financial impact of robotic spine surgery.

Minimally invasive spine surgery in the pediatric and adolescent population: A case series.

BACKGROUND: There is scant literature evaluating the indications, techniques, and outcomes of minimally invasive spine (MIS) surgery undertaken for pediatric and adolescent spine pathology. Our study attempts to evaluate the safe and effective use of MIS techniques in pediatric and adolescent patients and to appreciate the technical nuances of MIS surgery for this age group. METHODS: Consecutive pediatric and adolescent patients undergoing elective MIS lumbar procedures, from 2008 to 2016, were retrospectively analyzed from the practice of a single fellowship-trained academic spinal neurosurgeon. Information was retrieved regarding procedure and disease pathology. Descriptive data was obtained including age, sex, body mass index (BMI), insurance coverage, smoking status, and co-morbidities. Outcome measures were recorded including intraoperative complications, revision surgery, and return-to-function. RESULTS: Sixteen patients underwent 17 surgeries. The median BMI was 29.2 (range, 20.8-41.5). Age ranged from 12 to 19 years. Nearly 20% of the patients in our series were smokers. Most patients underwent discectomy, with L5-S1 being the most common level. One patient underwent direct pars defect repair and another underwent recurrent discectomy. More than 90% of the patients were complication-free at follow-up period of 6 months. One patient had a recurrent disc herniation and another had a superficial wound infection. Overall, 82.4% patients enjoyed full return to sports such as weight lifting, gymnastics, and contact sports. One patient required pain management to help alleviate ongoing pain. Another patient required a course of outpatient rehabilitation to help with a "foot drop." CONCLUSION: Our series illustrates the effective application of MIS techniques among carefully selected pediatric patients. Emphasis is on using a smaller (16 mm) tubular retractor and causing minimal disruption of paraspinal osseo-tendinous structures. MIS techniques can be successfully applied to the pediatric and adolescent age group.

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 functional magnetic resonance imaging in patients undergoing surgery for tumors around left (dominant) inferior frontal gyrus region.

BACKGROUND: Preoperative functional magnetic resonance imaging (fMRI) helps to preserve neurological function and ensure maximal tumor tissue excision. We studied the lateralization and localization of speech centers in select cases of tumors around the left (dominant) inferior frontal gyrus (IFG). METHODS: Twenty-three right-handed patients, harboring tumors involving the left (dominant) IFG or causing mass effect or edema extending onto the left IFG, were recruited over 17 months. Preoperatively, all patients underwent language and speech assessment followed by MRI and fMRI with paradigm (picture naming). Normative data for language fMRI was taken from the institute's imaging data bank. RESULTS: The study included 23 patients [mean age: 38.9 (±11.9) years; M: F = 16:7; 9 - normal speech, 14 - abnormal speech]. Group analysis of controls showed significant activation in the region of interest (ROI) - left Brodmann's areas (BAs) 44,45. Group analysis of patients with normal speech showed no activation in the left BAs 44,45; however, activation was noted in the immediate adjacent areas, left BAs 13,47 and contralateral prefrontal cortex. Group analysis of patients with impaired speech showed no activation in BAs 44,45 or in the immediate adjacent areas. CONCLUSIONS: Neuroplasticity in the brain may enable functional language areas to shift to adjoining or distant regions in the brain when the primary areas are involved by intrinsic tumors. This phenomenon is more likely in slow-growing compared to fast-growing tumors. Preoperative language fMRI may help us in identifying and protecting these areas during surgery.