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.

Health inequities and socioeconomic factors predicting the access to treatment for unruptured intracranial aneurysms in the USA in the last 20 years: interaction effect of race, gender, and insurance.

BACKGROUND: The literature suggests that minority racial and ethnic groups have lower treatment rates for unruptured intracranial aneurysms (UIA). It is uncertain how these disparities have changed over time. METHODS: A cross-sectional study using the National Inpatient Sample database covering 97% of the USA population was carried out. RESULTS: A total of 213 350 treated patients with UIA were included in the final analysis and compared with 173 375 treated patients with aneurysmal subarachnoid hemorrhage (aSAH) over the years 2000-2019. The mean (SD) age of the UIA and aSAH groups was 56.8 (12.6) years and 54.3 (14.1) years, respectively. In the UIA group, 60.7% were white patients, 10.2% were black patients, 8.6% were Hispanic, 2% were Asian or Pacific Islander, 0.5% were Native Americans, and 2.8% were others. The aSAH group comprised 48.5% white patients, 13.6% black patients, 11.2% Hispanics, 3.6% Asian or Pacific Islanders, 0.4% Native Americans, and 3.7% others. After adjusting for covariates, black patients (OR 0.637, 95% CI 0.625 to 0.648) and Hispanic patients (OR 0.654, 95% CI 0.641 to 0.667) had lower odds of treatment compared with white patients. Medicare patients had higher odds of treatment than private patients, while Medicaid and uninsured patients had lower odds. Interaction analysis showed that non-white/Hispanic patients with any insurance/no insurance had lower treatment odds than white patients. Multivariable regression analysis showed that the treatment odds of black patients has improved slightly over time, while the odds for Hispanic patients and other minorities have remained the same over time. CONCLUSION: This study from 2000 to 2019 shows that disparities in the treatment of UIA have persisted but have slightly improved over time for black patients while remaining constant for Hispanic patients and other minority groups.

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.

Drip and Ship versus Mothership Model in the Middle Cerebral Artery Stroke: A Propensity-Matched Real-World Analysis Through National Inpatient Sample Data.

BACKGROUND: The superiority of mechanical thrombectomy and intravenous thrombolysis versus intravenous thrombolysis alone for acute ischemic stroke caused by large vessel occlusions has been established. This treatment can be organized into 2 models: drip and ship (DS) versus mothership (MS). We analyzed the National Inpatient Sample (NIS) data to compare the outcomes between these models in real-world settings. METHODS: NIS data were queried for 2017-2018 and propensity matching was used to match the differences. Outcomes for each group (disability at discharge and procedural complications) were compared. RESULTS: A total of 1226 patients were included in analysis (DS, n = 540; MS, n = 686) and groups were matched with respect to age, gender, and comorbidities. A total of 930 patients were included in the final analysis after propensity matching (DS, n = 465, MS, n = 465). The mean age in the DS group was 68.9 years (standard deviation [SD], 14.7) and 69.4 years (SD, 14) in the MS group (P = 0.752). The mean National Institutes of Health Stroke Scale score was 16.75 (SD, 6.07) in the DS group and 16.54 (SD, 5.99) in the MS group (P = 0.478). At discharge, minimal disability was noted in 22.4% in the DS group versus 26.2% in the MS group (P = 0.293). In-hospital mortality was lower in the MS group (8.8% vs. 7.1%; P = 0.32). The intracerebral hemorrhage (ICH) and intraventricular hemorrhage (IVH) rates were higher in the DS group (ICH, 24.3% vs. 18.7%; IVH, 2.4% vs. 0.9%) (ICH, P = 0.038; IVH, P = 0.068). CONCLUSIONS: Analyzing the efficacy and safety profile of DS versus MS models with the NIS database showed a trend toward better discharge outcomes and lower mortality for the MS group, although it did not reach statistical significance.

Traumatic Subarachnoid-Pleural Fistula with Pneumocephalus.

Traumatic subarachnoid-pleural fistula is an uncommon occurrence. We present a case of a patient sustaining a subarachnoid-pleural fistula after a gunshot wound to the neck, which ultimately resulted in substantial pneumocephalus. The patient underwent successful operative repair of the fistula with notable improvement and resolution of pneumocephalus.

Multicenter Study for the Treatment of Sidewall versus Bifurcation Intracranial Aneurysms with Use of Woven EndoBridge (WEB).

Background The Woven EndoBridge (WEB) device was explicitly designed for wide-neck intracranial bifurcation aneurysms. Small-scale reports have evaluated the off-label use of WEB devices for the treatment of sidewall aneurysms, with promising outcomes. Purpose To compare the angiographic and clinical outcomes of the WEB device for the treatment of sidewall aneurysms compared with the treatment of bifurcation aneurysms. Materials and Methods A retrospective review of the WorldWideWEB Consortium, a synthesis of retrospective databases spanning from January 2011 to June 2021 at 22 academic institutions in North America, South America, and Europe, was performed to identify patients with intracranial aneurysms treated with the WEB device. Characteristics and outcomes were compared between bifurcation and sidewall aneurysms. Propensity score matching (PSM) was used to match by age, pretreatment ordinal modified Rankin Scale score, ruptured aneurysms, location of aneurysm, multiple aneurysms, prior treatment, neck, height, dome width, daughter sac, and incorporated branch. Results A total of 683 intracranial aneurysms were treated using the WEB device in 671 patients (median age, 61 years [IQR, 53-68 years]; male-to-female ratio, 1:2.5). Of those, 572 were bifurcation aneurysms and 111 were sidewall aneurysms. PSM was performed, resulting in 91 bifurcation and sidewall aneurysms pairs. No significant difference was observed in occlusion status at last follow-up, deployment success, or complication rates between the two groups. Conclusion No significantly different outcomes were observed following the off-label use of the Woven EndoBridge, or WEB, device for treatment of sidewall aneurysms compared with bifurcation aneurysms. The correct characterization of the sidewall aneurysm location, neck angle, and size is crucial for successful treatment and lower retreatment rate. © RSNA, 2022 See also the editorial by Hetts in this issue.

Extra-Arachnoidal Dissection and Limited Meatal Drilling for Excision of Giant Vestibular Schwannomas: Improved Facial Nerve Preservation.

Background: Surgical excision of giant (>4 cm size) vestibular schwannomas (VS) with preservation of facial nerve (FN) function remains a challenge. Objective: Our surgical technique using an extra-arachnoid plane of dissection and limited meatal drilling is described with the goal of improving FN preservation. Methods: Surgical results with respect to FN preservation were analyzed for two groups of giant VS patients: Group A-operated between 2002 and 2009 using "standard" surgical technique, group B-operated between 2009 and 2016 using extra-arachnoidal dissection and limited meatal drilling. All patients had a minimum follow-up of 1 year. Results: Group A: Of the 115 patients, total excision was possible in 103 (89.5%), near-total in 7 (6%), and subtotal in 5 (4.3%) patients. At a >6-month follow-up, 68 (59.1%) patients had good FN function (House-Brackmann [H&B] grades 1-2), while 21 (18.3%) patients had poor function (H&B grade 3-5). Grade 6 involvement was seen in 26 (22.6%). Five patients had lower cranial nerve impairment necessitating tracheostomy. Group B: Of the 98 patients, total excision was achieved in 70 (71.4%) patients, near-total in 9 (9.2%), and subtotal in 19 (19.4%). Four patients had repeat surgery; 14 underwent gamma-knife radiosurgery. At >6-month follow-up, 78 (79.5%) patients had good FN function (H&B grades 1-2), while 20 (20.4%) had poor function (H&B grade 3-5). Conclusions: With our 'modified' surgical technique of extra-arachnoidal dissection of VS throughout surgery and limited meatal drilling, an improved rate of functional FN preservation was observed.

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%).

"There's got to be a better way": Global Perspectives of Medicolegal Environment and Neurosurgical Socioeconomics.

Neurosurgery is considered to have one of the greatest risks of medical malpractice claims. However, medicolegal issues in neurosurgery are often disregarded and underrated worldwide. Medical errors in the neurosurgical field can be attributed to multiple factors, including highly morbid pathologies, the technical difficulty of neurosurgical procedures, and the involvement and interaction of a multidisciplinary team in the care of neurosurgical patients. Health care providers worldwide are at risk of lawsuits, sometimes even when no deviation from the standard of care had occurred in a given case. Often, governments use additional tactics to decrease the burden on compensators and extrajudicial institutions and to decrease the court's flow of irrational litigation. Continuous amendments to health care acts and newer reforms to address these issues have materialized worldwide. In the present narrative review, we have reviewed the global perspectives of medicolegal issues, with a focus on neurosurgical discipline.

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.

Venous Thromboembolism Prophylaxis in Elective Neurosurgery: A Survey of Board-Certified Neurosurgeons in the United States and Updated Literature Review.

BACKGROUND: Venous thromboembolism (VTE) remains the single most important preventable cause of morbidity and mortality following neurosurgical procedures, with an incidence of approximately 16%. In the absence of stringent guidelines, the variation in current practice patterns could be considerable and was the underlying basis for this study. OBJECTIVES: Our objective is to evaluate the modality of thromboprophylaxis used by neurosurgeons. METHODS: In line with "CHERRIES" (Checklist for Reporting Results of Internet E-Surveys) guidelines, an online survey regarding postoperative VTE prophylaxis following elective neurosurgical procedures was created using Google Forms and distributed to 1500 board-certified neurosurgeons in the United States. RESULTS: A total of 370 board-certified neurosurgeons (24.7%) responded to the survey. Sequential compression device was the only primary method of thromboprophylaxis used by 27.2% and 26.5% of respondents after elective craniotomy for tumor resection and spine surgery, respectively. Of the chemical prophylaxis, subcutaneous heparin 5000 U every 8 hours was the most commonly used medication followed by enoxaparin 40 mg daily. Most responders were comfortable starting chemical prophylaxis on postoperative day 1, followed by day 2 and day 3 in both types of surgeries. The mean postoperative time of chemical prophylaxis initiation was significantly more delayed by respondents with longer years in practice. CONCLUSIONS: This study highlights the variation in practice between neurosurgeons in managing postoperative VTE prophylaxis after elective spine and cranial surgeries. In lieu of this variation, our results showed that most neurosurgeons are comfortable starting chemical prophylaxis as soon as postoperative day 1 following both types of procedures.

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.

Spinal Fractures in Ankylosing Spondylitis: Patterns, Management, and Complications in the United States - Analysis of Latest Nationwide Inpatient Sample Data.

OBJECTIVE: Ankylosing spondylitis (AS) is a rheumatic inflammatory disease marked by chronic inflammation of the axial skeleton. This condition, particularly when severe, can lead to increased risk of vertebral fractures attributed to decreased ability of the stiffened spinal column to sustain normal loads. However, little focus has been placed on understanding the locations of spinal fractures and associated complications and assessing the correlation between these. In this review, we aim to summarize the complications and treatment patterns in the United States in AS patients with spinal fractures, using the latest Nationwide Inpatient Sample (NIS) database (2016-2018). METHODS: We analyzed the NIS data of years 2016-2018 to compare the fracture patterns and complications. RESULTS: A total of 5,385 patients were included. The mean age was 71.63 years (standard deviation [SD], 13.21), with male predominance (83.8%). The most common population is Whites (77.4%), followed by Hispanics (7.9%). The most common fracture level was thoracic level (58.3%), followed by cervical level (38%). Multiple fracture levels were found in 13.3% of the patients. Spinal cord injury (SCI) was associated with 15.8% of the patients. The cervical level had a higher proportion of SCI (26.5%), followed by thoracic level (9.2%). The mean Elixhauser comorbidity score was 4.82 (SD, 2.17). A total of 2,365 patients (43.9%) underwent surgical treatment for the fractures. The overall complication rate was 40.8%. Respiratory complications, including pneumonia and respiratory insufficiency, were the predominant complications in the overall cohort. Based on the regression analysis, there was no significant difference (p = 0.45) in the complication rates based on the levels. The presence of SCI increased the odds of having a complication by 2.164 times (95% confidence interval, 1.722-2.72; p ≤ 0.001), and an increase in Elixhauser comorbidity score predicted the complication and in-hospital mortality rate (p ≤ 0.001). CONCLUSION: AS patients with spinal fractures have higher postoperative complications than the general population. The most common fracture location was thoracic in our study, although it differs with few studies, with SCI occurring in 1/6th of the patients.

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.