M2 segment thrombectomy is not associated with increased complication risk compared to M1 segment: A meta-analysis of recent literature.

INTRODUCTION: Recent clinical comparisons of M1 and M2 segment endovascular thrombectomy have reached incongruous results in rates of complication and functional outcomes. This study aims to clarify the controversy surrounding this rapidly advancing technique through literature review and meta-analysis. METHODS: A Pubmed search was performed (January 2015-September 2019) using the following keywords: "M2 AND ("stroke" OR "occlusion") AND ("thrombectomy" OR "endovascular")". Safety and clinical outcomes were compared between segments via weighted Student's t-test, Chi-square and odds ratio while study heterogeneity was analyzed using Cochran Q and I2 tests. RESULTS: Pubmed identified 208 articles and eleven studies were included after full-text analysis, comprising 2,548 M1 and 758 M2 mechanical thrombectomy segment cases. Baseline National Institutes of Health Stroke Scale scores were comparatively lower in patients experiencing an M2 occlusion (16 ± 1.25 vs 13.6 ± 0.96, p < 0.01). Patients who underwent M2 mechanical thrombectomy were more likely to experience both good clinical outcomes (modified Rankin Scale 0-2) (48.6% vs 43.5% respectively, OR 1.24; CI 1.05-1.47, p = 0.01) and excellent clinical outcomes (modified Rankin Scale 0-1) (34.7% vs. 26.5%%, OR 1.6; CI 1.28-1.99, p < 0.01) at 90 days compared to M1 mechanical thrombectomy. Neither recanalization rates (75.3% vs 72.8%, OR 0.92, CI 0.75-1.13, p = 0.44) nor symptomatic intracranial hemorrhage rates (5.6% vs 4.9%, OR 0.92; CI 0.61-1.39, p= 0.7) were significantly different between M1 and M2 cohorts. Mortality was less frequent in the M2 cohort compared to M1 (16.3% vs 20.7%, OR 0.73; CI 0.57-0.94, p = 0.01). M1 and M2 cohorts did not differ in symptom onset-to-puncture (238.1 ± 46.7 vs 239.8 ± 43.9 min respectively, p=0.488) nor symptom onset-to recanalization times (318.7 ± 46.6 vs 317.7 ± 71.1 min respectively, p = 0.772), though mean operative duration was shorter in the M2 cohort (61.8 ± 25.5 vs 54.6 ± 24 min, p < 0.01). CONCLUSIONS: Patients who underwent M2 mechanical thrombectomy had a higher prevalence of good and excellent clinical outcomes compared to the M1 mechanical thrombectomy cohorts. Additionally, our data suggest lower mortality rates in the M2 cohort and symptomatic intracranial hemorrhage rates that are similar to the M1 cohort. Therefore, M2 segment thrombectomy likely does not pose a significantly elevated operative risk and may have a positive impact on patient outcomes.

Outcomes of treatment modalities for ruptured intracranial aneurysms based on age - A meta-analysis.

BACKGROUND: Data comparing the effect of age on outcomes of patients who underwent either endovascular coiling (EVC) or neurosurgical clipping (NSC) for ruptured intracranial aneurysms remains limited. OBJECTIVE: To better elucidate the preferred intervention for ruptured aneurysm management by presenting the results of our systematic review of the literature that evaluated the potential advantages of the two interventions between different age groups. METHODS: Systematic review of PubMed and Embase was performed (2002 - June 10, 2019) following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2013 guidelines. Median ages of EVC and NSC cohorts were 54 and 56, respectively. Ages below the median were used in our "younger" cohort; ages above the median were used in our "older" cohort. RESULTS: We reviewed 13 studies on 7,137 patients. In the younger cohort, there were 2840 (EVC: 1412, NSC: 1428) patients. In the older cohort, there were 4297 (EVC: 2552, NSC: 1745) patients. Overall, there was a significant difference in functionality between EVC (77.70%) and NSC (69.23%) (OR=1.69; 95% C.I.: 1.10-2.60, p = 0.0212). In our younger cohort, functionality was significantly different between EVC (77%) and NSC (69%) (OR=1.54; 95% C.I.: 1.29-1.84, p < 0.001). For the older cohort, there was no significant difference in functionality, complications, or efficacy. CONCLUSIONS: We have highlighted the importance of considering age prior to deciding which intervention is most appropriate for ruptured aneurysms, with higher morbidity and mortality with NSC versus EVC in the younger population.

Reconstruction of Complex Cranial and Orbit Fractures with Associated Hemorrhages: Case Report and Review of the Literature.

We present our experience following a unique case of coincident intracranial hemorrhage and comminuted fractures of both the squamous temporal bone and zygomaticofrontal orbit. Surgical techniques and outcome for this presentation have yet to be sufficiently described. A 55-year-old male presented following trauma with Glasgow Coma Scale score of 7. Radiographic evaluation revealed comminuted fractures of the squamous temporal bone with extension into the lateral orbit, along with zygomatic process fracture extending 2.5 cm medially into the orbital roof. Zygomaticofrontal orbital roof fragments reached superiorly into the middle cranial fossa and inferiorly into the orbit. Surgical intervention was deemed necessary to address underlying epidural hematoma, subarachnoid hemorrhage, correction of cranial bone defects, and decompression of the optic nerve and other intraorbital nerves. A frontotemporal approach was employed. Repair of temporal and orbital fractures was accomplished using a combination of wire mesh screws and titanium miniplates. Postoperative imaging demonstrated bony approximation and successful evacuation of traumatic hemorrhage. The patient remains functionally and neurologically intact apart from a sluggishly responsive left eye presumed to result from a left optic nerve or ciliary ganglion lesion. Although rapid reconstruction of complex cranial-orbital trauma and hematoma evacuation can permit acceptable gross functional neurological outcome following massive trauma, orbital fracture and subsequent hemorrhagic processes may be the nidus of neurological sequelae in this complex traumatic constellation. Thus, alterations in surgical approach and reconstruction are appropriate in order to maximize neurological function while supporting restoration of cosmetic space.

Does the Setting of External Ventricular Drain Placement Affect Morbidity? A Systematic Literature Review Comparing Intensive Care Unit versus Operating Room Procedures.

INTRODUCTION: External ventricular drain (EVD) placement can be performed at the bedside in the neurosurgical intensive care unit (ICU) or in the operating room (OR). Systematic review and meta-analysis may permit stronger recommendations to improve accuracy and complication rates. METHODS: Systematic review of PubMed was performed (inception-December 12, 2019) following PRISMA guidelines. RESULTS: Our search yielded 356 articles, of which 37 studies underwent full-text analysis. Nine studies met inclusion criteria. Studies were segregated into OR only (n = 3; 1011 patients), ICU only (n = 3; 325 patients), and OR + ICU (n = 3; 613 patients) cohorts. Studies were in addition divided by outcome measures, including catheter placement accuracy (ICU, 4 studies, n = 280 [68.29%] vs. OR, 2 studies, n = 198 [84.25%]); iatrogenic hemorrhagic complications (ICU, 4 studies, n = 112 [18.16%] vs. OR, 2 studies, n = 35 [17.50%]); and ventriculostomy-related infection rates (ICU, 4 studies, n = 48 [7.28%] vs. OR: 5 studies, n = 92 [8.06%]). CONCLUSIONS: There are likely specific patient populations who would benefit from EVD placement in the ICU versus OR setting. The literature comparing efficacy and morbidity between EVDs placed in the ICU and OR settings is overall inconclusive in both sample size and congruence of methodology. Agreement in outcome metrics and data reporting on this topic is necessary to synthesize high-quality evidence to form practice-changing recommendations for this debated topic.

Usefulness and Impact of Intraoperative Imaging for Glioma Resection on Patient Outcome and Extent of Resection: A Systematic Review and Meta-Analysis.

BACKGROUND: Diffusion tensor imaging (DTI), functional magnetic resonance imaging (fMRI), and intraoperative magnetic resonance imaging (iMRI) permit greater visualization and more accurate presurgical planning. Meta-analysis of these techniques for maximizing resection, postoperative functionality, and survival may further validate purported strengths of these techniques compared with standard neuronavigation. METHODS: A systematic search of the PubMed database was conducted in line with the PRISMA guidelines for meta-analysis with the following keywords: "Diffusion tensor imaging" OR "intraoperative MRI" OR "functional MRI" AND "glioma surgery resection outcome." Articles found to meet inclusion criteria were segregated and analyzed and resulting data were compared with standard neuronavigation (control cohort). RESULTS: A total of 435 articles were identified, with 29 distinct studies meeting inclusion criteria, including DTI (n = 3), fMRI (n = 5), and iMRI (n = 21). Nine studies directly compared results with standard navigation. Mean gross total resection (GTR) rates were not different among cases using DTI, fMRI, iMRI, or traditional neuronavigation (P = 0.136). On controlling for covariates, more patients received GTR in the advanced imaging cohort, although statistically insignificant (46.5% [95% confidence interval, 38.0%-55.0%] vs. 30.4% [95% confidence interval, 11.6%-49.1%]; P = 0.127; partial η2 = 0.217). Patients undergoing advanced imaging showed attenuated incidence of postsurgical permanent neurologic deficits, although also statistically insignificant (11.3% vs. 13.8%; P = 0.838). CONCLUSIONS: Current data are overall insufficient to support the notion that advanced imaging techniques are superior, either as a combined cohort or individually, in achieving GTR, improved symptom resolution, or survival compared with traditional neuronavigation.

A Successful Outcome Despite Delayed Intervention for Cauda Equina Syndrome in a Young Patient with a Posterior Epidural Disc Extrusion.

Epidural disc extrusion is extremely rare and may cause cauda equina syndrome. This is a surgical emergency and needs rapid decompression. Although cauda equina is commonly caused by disc herniation, this is an unusual presentation with epidural disc extrusion. We present a very rare case of Cauda Equina syndrome, resulting from an epidural disc extrusion at L3-L4 level. Patient care and progress notes were reviewed along with pre-, post-, and intra-operative radiological imaging. Here, a 19-year-old male with a past medical history of type I diabetes mellitus, fell asleep on a chair at home in an unusual position and was unable to walk on awakening. The patient developed progressive neurological deficits including bilateral foot drop along with bowel and bladder dysfunction. In addition, he experienced paresthesia and severe lower back pain unresponsive to steroids. Pre-operative magnetic resonance imaging (MRI) demonstrated a herniated disk epidurally with disc extrusion and mass effect and compression at the L3-L4 level, wrapping around the posterior aspect of the dura. A diagnosis of cauda equina syndrome was made and surgical decompression was performed. Using microsurgical technique and fluoroscopic guidance, a bilateral laminectomy of L3 was achieved with bilateral partial laminectomy of L4, with bilateral foraminotomy of L4. After removal of the lamina, a mass was immediately visualized in the posterior epidural space. Further dissection of the substance and following it posteriorly, identified the mass as a portion of the extruded disc. Post-operatively, the patient experienced rapid recovery. In conclusion, this case demonstrates that a disc extrusion can occur within the epidural space and can cause cauda equina syndrome. As this presentation is unusual, surgeons must be aware that they may encounter disc mass in unexpected locations, in a clinically delayed setting, long after the initial onset of symptoms.

Immunological, vascular, metabolic, and autonomic changes seen with aging possible implications for poor outcomes in the elderly following decompressive hemicraniectomy for malignant MCA stroke: a critical review.

INTRODUCTION: Stroke is one of the leading causes of mortality and morbidity worldwide and requires rapid and intensive treatment to prevent adverse outcomes. Decompressive hemicraniectomy stands as the gold standard for surgical resolution of the intracranial swelling which accompanies cerebral infarction; however, the benefits of this procedure are not as well achieved in the elderly (age >65 years) compared to the younger population. EVIDENCE ACQUISITION: This is a critical review performed on all available literature relating to middle cerebral artery (MCA) stroke in the elderly with emphasis on articles examining causality of adverse outcomes in this group over younger populations. Utilizing PRISMA guidelines, we initially identified 1462 articles. EVIDENCE SYNTHESIS: After screening, four clear areas of physiological change associated with aging were identified and expounded upon as they relate to MCA stroke. These four areas include: immunological, autonomic, mitochondrial, and vascular changes. Elderly patients have a decreased and declining capacity to regulate the inflammation that develops postinfarction and this contributes to adverse outcomes from a neurological stand point. Additionally, aging decreases the ability of elderly patients to regulate their autonomic system resulting in aberrant blood pressures systemically post infarction. With age, the mitochondrial response to ischemia is exaggerated and causes greater local damage in elderly patients compared to younger populations. Finally, there are numerous vascular changes that occur with age including accumulation of homocysteine and atherosclerosis which together contributed to decreased structural integrity of the vasculature in the elderly and render decreased support to the recovery process post infarction. CONCLUSIONS: We conclude that physiological changes inherent in the aging process serve to intensify adverse outcomes that are commonly associated with strokes in the elderly. Identification and subsequent minimization of these risk factors could allow for more effective management of elderly patients, post stroke, and promote better clinical outcomes.

Virtual Reality-Based Simulators for Cranial Tumor Surgery: A Systematic Review.

BACKGROUND: Virtual reality (VR) simulators have become useful tools in various fields of medicine. Prominent uses of VR technologies include assessment of physician skills and presurgical planning. VR has shown effectiveness in multiple surgical specialties, yet its use in neurosurgery remains limited. OBJECTIVE: To examine all current literature on VR-based simulation for presurgical planning and training in cranial tumor surgeries and to assess the quality of these studies. METHODS: PubMed and Embase were systematically searched to identify studies that used VR for presurgical planning and/or studies that investigated the use of VR as a training tool from inception to May 25, 2017. RESULTS: The initial search identified 1662 articles. Thirty-seven full-text articles were assessed for inclusion. Nine studies were included. These studies were subdivided into presurgical planning and training using VR. CONCLUSIONS: Prospects for VR are bright when surgical planning and skills training are considered. In terms of surgical planning, VR has noted and documented usefulness in the planning of cranial surgeries. Further, VR has been central to establishing reproducible benchmarks of performance in relation to cranial tumor resection, which are helpful not only in showing face and construct validity but also in enhancing neurosurgical training in a way not previously examined. Although additional studies are needed to better delineate the precise role of VR in each of these capacities, these studies stand to show the usefulness of VR in the neurosurgery and highlight the need for further investigation.

In vitro testing of current spread during ventricular catheter coagulation using diathermy. Technical note.

The authors report on the development of an anterior cerebral artery pseudoaneurysm that hemorrhaged after monopolar coagulation for a ventricular catheter lodged in the interhemispheric fissure. After observing this complication, the authors developed a simple bench test that can be performed by any neurosurgeon to determine the safest coagulation parameters for any given diathermy unit. A modified grounding pad was placed in a beaker of a protein solution consisting of egg whites. Ventricular catheters were then placed in the solution, and a monopolar diathermy current was applied to a metal stylet at various wattages and for different durations of time. Inducing coagulation at 40 W with a diathermy unit produced flames emanating from around the pores of the catheter tip. Flash flames were also observed at 35 W, forming a coagulum of egg white for a distance of up to 1 cm from the catheter tip. All heat was dissipated through the holes of the first 16 mm of the catheter. At 20 W the flame was minimal and coagulation appeared adequate, whereas at 15 W only bubbles were seen around the tip together with suboptimal coagulum formation. This technique is a simple and effective means of determining the optimal setting for monopolar diathermy and can be used to figure the optimal catheter coagulation wattage for a given diathermy unit. Considering the results of this study, the authors have lowered the current for coagulation in ventricular catheters to 20 W.

The Art of Mimicry: Anterior Clinoid Dural-Based Cavernous Hemangioma Mistaken for a Meningioma.

BACKGROUND: Cavernous hemangiomas account for 5%-13% of central nervous system vascular lesions. They are usually found intra-axially but rarely involve extra-axial structures, most commonly the middle cranial fossa. A cavernous hemangioma manifesting as a clinoid meningioma is extremely rare. CASE DESCRIPTION: A 36-year-old man presented with an asymptomatic intracranial mass found incidentally after a motor vehicle accident. Preoperative magnetic resonance imaging revealed a well-defined dural-based lesion arising from the right anterior clinoid process that was nearly homogeneously enhancing. The radiologic diagnosis was meningioma. The mass was resected via a right pterional craniotomy with microsurgical technique. Complete resection of the mass was performed with no complications and no significant bleeding. Contrasting with the radiologic and gross tumor appearance, histopathologic examination revealed dilated vascular spaces, sclerotic vessels without intervening neural tissue, and intravascular thrombi suggesting slow blood flow-all consistent with cavernous hemangioma. CONCLUSIONS: Anterior clinoid dural-based cavernous hemangiomas are extremely rare. Although preoperative diagnosis is difficult using imaging, this etiology should be considered for any dural-based middle fossa lesion, owing to the tendency for these lesions to bleed heavily during resection in some instances.

A Unique Case of Carotid Splaying by a Cervical Vagal Neurofibroma and the Role of Neuroradiology in Surgical Management.

Carotid splaying, also known as the Lyre sign, is a widening of the carotid bifurcation due to the displacement of the internal carotid artery and the external carotid artery just distal to the point of divergence. This phenomenon is classically exhibited by highly vascularized carotid body tumors and, in rare cases, by cervical sympathetic chain schwannomas. Demonstration of the Lyre sign by a cervical vagal neurofibroma, however, is a unique occurrence that has not been previously documented in the literature. Neurofibromas are slow growing, poorly vascularized soft tissue masses and are a hallmark of the autosomal dominant genetic disorder, neurofibromatosis type 1 (NF-1). While targeted genetic therapies are evolving, management is currently dependent on a case-by-case resection of tumors with specific indications for chemo and radiation therapy. These resections rely on magnetic resonance imaging (MRI) to visualize tumor location and infiltration, but even in the setting of an established NF-1 diagnosis, additional imaging can be beneficial in ruling out more precarious tumors and optimizing surgical outcomes. In this case, a 25-year-old female with known NF-1 presented with an enlarging cervical mass that demonstrated splaying of the left internal and external carotid arteries on MRI. Due to the typical association of the Lyre sign with carotid body tumors, magnetic resonance angiography (MRA) was crucial in guiding surgical decision making. Carotid body tumors are highly vascularized, may compress carotid branches, and carry a high risk of intraoperative bleeding. They are best visualized with MRA, which assesses carotid splaying and patency, and demonstrates vascular blushing within the tumor.  This patient's MRA demonstrated the Lyre sign, patency of all carotid vessels, and a lack of vascularity within the mass, thus lowering suspicion for a carotid body tumor. Intraoperative use of imaging results facilitated a successful resection of a soft tissue tumor with minimal blood loss and no complications. Postoperative histologic examination confirmed a neurofibroma and definitively ruled out a carotid body tumor. This case highlights the importance of utilizing MRA whenever carotid splaying is seen on MRI and supports the consideration of neurofibromas in the differential for this finding.

Predictors of Outcomes in Traumatic Brain Injury.

INTRODUCTION: The purpose of this study was to retrospectively evaluate patients treated for traumatic brain injuries (TBI) to determine how multiple organ trauma (MOT) and lung injuries sustained at the time of initial injury affect outcome. METHODS: A single institution retrospective review of all patients diagnosed with TBI at a level I trauma center from 2000 to 2014 was conducted. Clinical outcome was based on Glasgow Outcome Scale at hospital discharge. Lung injury was defined as the presence of pulmonary contusions, pneumothorax, hemothorax, rib fractures, or diaphragmatic rupture proven by x-ray or computed tomography scan. MOT was defined as trauma to one body region with an Abbreviated Injury Scale (AIS) score ≥3 plus trauma to 2 additional body regions with AIS scores ≥1. Regression analysis was conducted with SPSS 21. RESULTS: There were 409 patients reviewed. The majority of patients were male (73%), average age was 46 years (range, 16-94 years), average Glasgow Coma Scale (GCS) score was 7, and 71% had a severe TBI (GCS ≤8). Thirty percent of patients had poor outcome (Glasgow Outcome Scale = 1-2) Regression analysis indicated age (odds ratio [OR] 1.03, P < 0.001), initial GCS (OR 0.88, P < 0.001), Injury Severity Score (OR 1.03, P = 0.021), and head AIS ≥5 (OR 0.55, P = 0.019) were significant independent predictors of poor outcome. Sex, MOT, lung injury, and lung injury severity were not significant predictors of outcome. CONCLUSIONS: Age, GCS, Injury Severity Score, and critical head injuries (AIS ≥5) were significant tools in predicting outcome in this patient cohort. MOT and traumatic lung injury may cause significant damage to a patient suffering from a severe TBI, but these injuries do not predict mortality in this patient population.

Is There a Genetic Correlation between Multiple Sclerosis and Cerebral Aneurysms?

BACKGROUND: Multiple sclerosis (MS) is a common autoimmune and neurodegenerative disease of the central nervous system characterized by inflammatory demyelination, axonal degeneration, and neuronal loss. The exact pathogenesis of MS remains uncertain; however, studies have shown that the development of MS is influenced by genetic and environmental factors. Cerebral aneurysms (CAs) are life-threatening lesions of cerebral vessels characterized by a bulge in the intracranial arterial wall that spontaneously ruptures. It has been hypothesized that patients with MS are at increased risk of developing cerebral aneurysms. This hypothesis can be supported by analyzing the pathogenesis and genetics of the development of MS and CA. To our knowledge, no previous studies have shown an association between MS and CA. CASE DESCRIPTION: In this report, we performed middle cerebral artery aneurysm clipping for two patients with MS who were referred to our clinic for CA in the bifurcation of middle cerebral artery that was found incidentally on magnetic resonance imaging. We aim to identify any genetic correlation between MS and CA pathogenesis. CONCLUSION: This report suggests a possible genetic association between MS and CAs. The strongest evidence of association was found for the TNFRSF1A gene, a proinflammatory gene that is involved in mitogen-activated protein kinase (MAPK) and NF-Kappa B signaling pathways, and has been identified as a candidate gene in the development of MS. MAPKs were also found to be elevated in CAs.

Extremely rare glioblastoma multiforme of the conus medullaris with holocord and brain stem metastases, leading to cranial nerve deficit and respiratory failure: a case report and review of the literature.

BACKGROUND: Spinal glioblastoma multiforme (GBM) is an uncommon entity and metastases are extremely rare. Glioblastoma multiforme of the conus medullaris is a rare and highly aggressive entity that can quickly progress to a dismal state. Proper diagnosis via histopathologic and immunochemical staining with close clinical and radiological follow-up is important for the management of this very aggressive tumor. CASE DESCRIPTION: The authors report the clinical features, histopathologic and immunochemical staining characteristics, as well as the radiographic evidence of a case of primary GBM of the conus medullaris with metastases to the whole spinal cord and brain in a 20-year-old man who presented with low back pain and bilateral lower extremity weakness and numbness. Review of the pathology slides using histopathologic and immunochemical staining showed GBM. Serial magnetic resonance scans, performed after the initial surgery, demonstrated enlargement of the primary GBM in the conus medullaris with metastases to the thoracic and cervical spinal cord as well as to the brain. CONCLUSIONS: Glioblastoma multiforme of the conus medullaris with such clinical findings is extremely rare. We analyze similar cases in the literature and discuss the importance of monitoring the progression of such an entity as well as the need for aggressive management of the different complications as they arise to maintain a good quality of life.

Posterior Reversible Encephalopathy Syndrome Secondary to CSF Leak and Intracranial Hypotension: A Case Report and Literature Review.

Posterior Reversible Encephalopathy Syndrome (PRES) is a clinical neuroradiological condition characterized by insidious onset of neurological symptoms associated with radiological findings indicating posterior leukoencephalopathy. PRES secondary to cerebrospinal fluid (CSF) leak leading to intracranial hypotension is not well recognized etiology of this condition. Herein, we report a case of PRES that occurred in the setting of CSF leak due to inadvertent dural puncture. Patient underwent suturing of the dural defect. Subsequently, his symptoms resolved and a repeated brain MRI showed resolution of brain lesions. The pathophysiology and mechanistic model for developing PRES in the setting of intracranial hypotension were discussed. We further highlighted the importance of tight blood pressure control in patients with CSF leak and suspected intracranial hypotension because they are more vulnerable to develop PRES with normal or slightly elevated bleed pressure values.

Surgical outcomes after posterior fossa decompression with and without duraplasty in Chiari malformation-I.

INTRODUCTION: Chiari malformation-I (CM) is one of the most controversial entities in the contemporary neurosurgical literature. Posterior fossa decompression (PFD) is the preferred treatment for CM with and without syringomyelia. A variety of surgical techniques for PFD have been advocated in the literature. The aim of this study was to evaluate our results of surgically treated patients for CM-I with and without syringomyelia; using extradural dura-splitting and intradural intraarachnoid techniques. METHODS: A retrospective review of the medical records of all the patients undergoing PFD was conducted. Symptomatic patients with tonsillar herniation≥3-mm below the foramen magnum on neuroimaging, and CSF flow void study demonstrating restricted or no CSF flow at the craniocervical junction, were offered surgical treatment. In patients without syringomyelia, extradural decompression with thinning of the sclerotic tissue at the cervicomedullary junction and splitting of outer dural layer was performed. In patients with syringomyelia, the dura was opened and an expansile duraplasty was performed. RESULTS: The mean age of 8 males and 34 females was 33.8 years (range, 16-58 years). Headache (39/41; 95%), and/or tingling and numbness (17/41; 42%) were the most common presenting symptoms. The syrinx was associated with CM-I in 5/41 (12%) patients. PFD without durotomy was performed in 29/41 (73%) patients. The mean duration of preoperative symptoms was significantly longer in duraplasty group (4.6 versus 1.7 years, P=0.005, OR=0.48, CI=0.29-0.8). The use of duraplasty was significantly associated with presence of complications (P=0.004, OR=0.5, CI=0.3-0.8) and longer duration of hospital stay (P=0.03, OR=2.7, CI=1.1-6.8). The overall complication rate was 6/41(15%) patients. The overall improvement rate was evident in 84% (36/41); 12% (5/41) were stable; and 5% (2/41) had worsening of symptoms. The history of prior CM decompression was associated with unfavorable outcomes (P=0.04, OR=14, CI=1.06-184). One patient experienced recurrence one year after the PFD with duraplasty. CONCLUSION: The present study reports favorable surgical outcomes with extra-dural decompression of the posterior fossa in patients CM-I without syringomyelia. For patients with syringomyelia and history of prior PFD, intradural intra-arachnoid decompression is required. The prior history of decompression was associated with unfavorable outcomes. The use of duraplasty was associated with longer duration of hospital stay and higher complication rate. Further large cohort prospective study is needed to provide any recommendation on the indication of intra or extradural decompression for a given CM-I patient.

External lumbar drain: A pragmatic test for prediction of shunt outcomes in idiopathic normal pressure hydrocephalus.

BACKGROUND: The consensus on most reliable supplemental test to predict the shunt responsiveness in patients with idiopathic normal pressure hydrocephalus (iNPH) is lacking. The aim of this study is to discuss the utility of external lumbar drain (ELD) in evaluation of shunt responsiveness for iNPH patients. METHODS: A retrospective review of 66 patients with iNPH was conducted. All patients underwent 4-day ELD trial. ELD-positive patients were offered ventriculoperitoneal shunt (VPS) surgery. The primary outcome evaluation parameters were gait and mini mental status examination (MMSE) assessment. The family and patient perception of improvement was accounted for in the outcome evaluation. RESULTS: There were 38 male and 28 female with mean age of 74 years (range 45-88 years). ELD trial was positive in 86% (57/66) of patients. No major complications were encountered with the ELD trial. A total of 60 patients (57 ELD-positive, 3 ELD-negative) underwent VPS insertion. The negative ELD trial (P = 0.006) was associated with poor outcomes following shunt insertion. The positive ELD trial predicted shunt responsiveness in 96% patients (P < 0.0001, OR = 96.2, CI = 11.6-795.3). A receiver operating characteristic (ROC) curve analysis revealed that the ELD trial is reasonably accurate in differentiating shunt responder from non-responder in iNPH patients (area under curve = 0.8 ± 0.14, P = 0.02, CI = 0.52-1.0). The mean follow-up period was 12-months (range 0.3-3 years). The significant overall improvement after VPS was seen in 92% (55/60). The improvement was sustained in 76% of patients at mean 3-year follow-up. The number of comorbid conditions (P = 0.034, OR = 4.15, CI = 1.2-9.04), and a history of cerebrovascular accident (CVA) (P = 0.035, OR = 4.4, CI = 1.9-14.6) were the predictors of poor outcome following shunt surgery. CONCLUSION: The positive ELD test predicted shunt responsiveness in 96% of patients. With adequate technique, maximal results with minimal complications can be anticipated. The number of comorbidities, history of CVA and negative ELD test were significantly associated with poor shunt outcomes.