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.

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.

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.

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.

Jacques Jean Lhermitte and the syndrome of peduncular hallucinosis.

Jacques Jean Lhermitte (1877-1959) was among the most accomplished neurologists of the 20th century. In addition to working as a clinician and instructor, he authored more than 800 papers and 16 books on neurology, neuropathology, psychiatry, and mystical phenomena. In addition to the well-known "Lhermitte's sign," an electrical shock-like sensation caused by spinal cord irritation in demyelinating disease, Lhermitte was a pioneer in the study of the relationship between the physical substance of the brain and the experience of the mind. A fascinating example of this is the syndrome of peduncular hallucinosis, characterized by vivid visual hallucinations occurring in fully lucid patients. This syndrome, which was initially described as the result of a midbrain insult, also may occur with injury to the thalamus or pons. It has been reported as a presenting symptom of various tumors and as a complication of neurosurgical procedures. Here, the authors review the life of Lhermitte and provide a historical review of the syndrome of peduncular hallucinosis.

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

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

A comparison of the techniques of direct pars interarticularis repairs for spondylolysis and low-grade spondylolisthesis: a meta-analysis.

OBJECTIVE Spondylosis with or without spondylolisthesis that does not respond to conservative management has an excellent outcome with direct pars interarticularis repair. Direct repair preserves the segmental spinal motion. A number of operative techniques for direct repair are practiced; however, the procedure of choice is not clearly defined. The present study aims to clarify the advantages and disadvantages of the different operative techniques and their outcomes. METHODS A meta-analysis was conducted in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. The following databases were searched: PubMed, Cochrane Library, Web of Science, and CINAHL ( Cumulative Index to Nursing and Allied Health Literature). Studies of patients with spondylolysis with or without low-grade spondylolisthesis who underwent direct repair were included. The patients were divided into 4 groups based on the operative technique used: the Buck repair group, Scott repair group, Morscher repair group, and pedicle screw-based repair group. The pooled data were analyzed using the DerSimonian and Laird random-effects model. Tests for bias and heterogeneity were performed. The I2 statistic was calculated, and the results were analyzed. Statistical analysis was performed using StatsDirect version 2. RESULTS Forty-six studies consisting of 900 patients were included in the study. The majority of the patients were in their 2nd decade of life. The Buck group included 19 studies with 305 patients; the Scott group had 8 studies with 162 patients. The Morscher method included 5 studies with 193 patients, and the pedicle group included 14 studies with 240 patients. The overall pooled fusion, complication, and outcome rates were calculated. The pooled rates for fusion for the Buck, Scott, Morscher, and pedicle screw groups were 83.53%, 81.57%, 77.72%, and 90.21%, respectively. The pooled complication rates for the Buck, Scott, Morscher, and pedicle screw groups were 13.41%, 22.35%, 27.42%, and 12.8%, respectively, and the pooled positive outcome rates for the Buck, Scott, Morscher, and pedicle screw groups were 84.33%, 82.49%, 80.30%, and 80.1%, respectively. The pedicle group had the best fusion rate and lowest complication rate. CONCLUSIONS The pedicle screw-based direct pars repair for spondylolysis and low-grade spondylolisthesis is the best choice of procedure, with the highest fusion and lowest complication rates, followed by the Buck repair. The Morscher and Scott repairs were associated with a high rate of complication and lower rates of fusion.

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.

Pattern of reporting and practices for the management of traumatic brain injury: An overview of published literature from India.

BACKGROUND: Published literature regarding the demographics and mechanism of injury for traumatic brain injury (TBI) in India has not been analyzed in an organized sample. OBJECTIVES: The objective of this systematic review was to organize the published literature from India related to TBI and analyze it in a very specific sample to identify the specific patterns of injury and associated mortality. MATERIALS AND METHODS: A search strategy with specific inclusion criteria was performed in PubMed, Cochrane, Web of Science, and the World Health Organisation (WHO) Global Health Library. The process included an additional search within the indexed literature and the website-based population survey reports. RESULTS: Our review identified 72 studies from 300 potentially relevant articles based on the broad criteria that defined the demographics of the patients suffering from TBI and the details of trauma sustained, including the mechanism of injury as well as its diagnosis, management, and outcome. Changes in demographic patterns, the patterns of the body regions involved, the associated injuries, the clinical presentation, the follow-up status of patients suffering from TBI, who may or may not have shown clinical improvement, the overall outcome, as well as the mortality and disability status reported in the literature were analyzed. A high incidence of TBI in the productive population is of serious concern. Extremes of ages are more vulnerable to severe injury and a poor outcome. CONCLUSION: Quantitative analysis of injuries and outcomes of TBI victims shows a bigger health impact in the economically active population and in patients in the extremes of age groups.

Intraventricular gliosarcoma with dual sarcomatous differentiation: A unique case.

Gliosarcoma, a variant of isocitrate dehydrogenase-wildtype glioblastoma, is largely a lobar surfacing neoplasm often with dural attachment. In this biphasic neoplasm, the sarcomatous component usually takes the form of fibrosarcoma or malignant fibrous histiocytoma. Heterologous sarcomatous differentiation is a rare phenomenon. Here, we present a case of gliosarcoma with liposarcomatous and myosarcomatous differentiation in a 68-year-old man which was purely intraventricular. This is the first report of such a morphologic pattern in this location. Varied histological components with their immunohistochemical profile are discussed. Of note was the presence of a p53 negative giant cell glioblastoma component, as was the expression in the rest of the tumor.

Resection of posterior clinoid meningioma through retrosigmoid approach: concepts and nuances.

Meningiomas arising from the posterior clinoid process pose a great surgical challenge because of their location and propensity to cause critical neurovascular compression. The authors' patient was a 66-year-old female who had a large posterior clinoid meningioma with significant brainstem compression that was operated on through the retrosigmoid approach. This 3D surgical video emphasizes the various technical concepts that are important to preserving compressed neural and vascular structures during the surgery. It would also be interesting to note the extent of visualization around the posterior clinoid region gained through a retrosigmoid corridor. The video can be found here: https://youtu.be/CBmT_0ov0YA .

The 21st-century challenge to neurocritical care: the rise of the superbug Acinetobacter baumannii. A meta-analysis of the role of intrathecal or intraventricular antimicrobial therapy in reduction of mortality.

OBJECTIVE Neurosurgical infections due to multidrug-resistant organisms have become a nightmare that neurosurgeons are facing in the 21st century. This is the dawn of the so-called postantibiotic era. There is an urgent need to review and evaluate ways to reduce the high mortality rates due to these infections. The present study evaluates the efficacy of combined intravenous plus intrathecal or intraventricular (IV + IT) therapy versus only intravenous (IV) therapy in treating postneurosurgical Acinetobacter baumannii infections. METHODS The authors performed a meta-analysis of all peer-reviewed studies from the PubMed, Cochrane Library database, ScienceDirect, and EMBASE in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Five studies were finally included in the present analysis: 126 patients were studied who had postneurosurgical A. baumannii infection. The Cochrane collaboration tool was used to evaluate risk of bias, and a test of heterogeneity was performed. The I2 statistic was calculated. The patients were divided into 2 groups: the IV group received only intravenous therapy and the IV + IT group received both intravenous and intrathecal or intraventricular antimicrobial therapy. The outcome was mortality attributed specifically to A. baumannii infection in postneurosurgical cases. The pooled data were analyzed using the Cochran-Mantel-Haenszel method in a fixed-effects model. RESULTS The total number of patients in the IV-only group was 73, and the number of patients in the IV + IT group was 53. The mean duration of intravenous therapy was 27 days. The mean duration of intrathecal colistin was 21 days. The intravenous dose of colistin ranged from 3.75 to 8.8 MIU per day. The dose of intrathecal colistin ranged between 125,000 and 250,000 IU per day. The overall calculated odds ratio for mortality for the IV + IT group after pooling the data was 0.16 (95% CI 0.06-0.40, p < 0.0001). The patients who received IV + IT therapy had an 84% lower risk of dying due to the infection compared with those who received only IV therapy. CONCLUSIONS There is an 84% lower risk of mortality in patients who have been treated with combined intrathecal or intraventricular plus intravenous antimicrobial therapy versus those who have been treated with intravenous therapy alone. The intrathecal or intraventricular route should be strongly considered when dealing with postneurosurgical multidrug-resistant A. baumannii infections.

Unusual Occurrence of Multifocal Desmoplastic Infantile Astrocytoma: A Case Report and Review of the Literature.

Desmoplastic infantile gliomas are rare, benign tumors of the early infancy period. Two histological subtypes - desmoplastic infantile astrocytoma (DIA) and desmoplastic infantile ganglioglioma - have been described. The characteristic features of DIAs are lobar location, glial histology, and excellent prognosis after complete surgical excision. DIAs usually present as solitary, cortical-surfacing, solid-cystic neoplasms; however, atypical, aggressive, and multifocal variants of DIA have been reported in the literature. These rare DIAs presenting with multiple lesions pose a diagnostic as well as a therapeutic dilemma. We report an unusual case of an 8-month-old female infant diagnosed with multifocal (cranial and spinal) DIA and obstructive hydrocephalus and discuss the radiological and histological features of this rare variant of DIA. The patient underwent ventriculoperitoneal shunt placement to relieve the hydrocephalus, excisional biopsy from a surfacing lesion in the right frontal lobe, and multiple cycles of chemotherapy; however, the lesions continued to progress, and the patient is likely to have an unfavorable outcome.

Giant Hypothalamic Hamartoma in an Infant: A Case Report and Review of the Literature.

Giant hypothalamic hamartomas (GHH) are extremely rare lesions in infants and usually intrinsically epileptogenic. We present the case of a 10-month-old girl child presenting with drug-resistant seizures and a giant hypothalamic lesion that was confirmed as hamartoma on histopathology. Surgical decompression and disconnection from the hypothalamus was performed with the intent of controlling her seizures. Unfortunately, the patient developed right middle cerebral artery and posterior cerebral artery territory infarction, possibly due to vasospasm or thrombosis of the vessels. The patient had a stormy postoperative course but has recovered well neurologically at the 18-month follow-up. Histopathological examination revealed abnormal clusters of NeuN-positive neurons, which was confirmatory of hypothalamic hamartoma. A review of the published literature on infantile GHH, its management and the postoperative complications is undertaken in this short report.

Tuberculous brain abscesses in immunocompetent patients: A decade long experience with nine patients.

OBJECTIVE: To describe the clinical presentation, radiological findings, management details, and outcome in nine cases of tuberculous brain abscess (TBA). MATERIALS AND METHODS: Nine patients (5 females, 4 males) harboring a TBA, as defined by the Whitener's criteria, were managed over a span of one and a half decade by the authors. All, except one patient, underwent contrast-enhanced magnetic resonance imaging scans, followed by surgical excision of the abscesses due to the failure of complete resolution of the lesion after its drainage using a burr-hole. RESULTS: The infra-tentorial location (n = 4) in TBAs was as common as the supra-tentorial location (n = 4). All large TBAs (more than 3 cm in diameter) failed to resolve after tapping of the purulent material and required surgical excision for a favorable long-term outcome. Two patients expired, while seven patients survived with Karnofsky Performance scale of 90 for 3, 80 for 3, and 70 for 1 patient. The follow-up ranged from 2 to 12 years (mean = 5.7 years). CONCLUSION: TBAs should be considered in the list of differential diagnoses for pyogenic abscesses, especially in developing countries, as it is difficult to differentiate between them on the basis of clinical or radiological findings. Hence, all pus samples should be sent for Ziehl-Neelsen staining and culture for Mycobacterium tuberculosis. Surgically excised and pathologically evaluated specimens remain the gold-standard for diagnosing TBAs. Larger abscesses warrant surgical excision, while concomitantly associated smaller lesions tend to resolve with prolonged antituberculous therapy.

Spontaneous hemorrhages in pediatric supratentorial pilocytic astrocytomas. Malignant presentation of a benign entity.

BACKGROUND: Hemorrhage as a presenting feature in pilocytic astrocytoma is an extremely rare phenomenon. When seen in children, most of such tumors exist in the cerebellum. Rarely, a supratentorial pilocytic astrocytoma can present with bleeding. RESULTS: We present similar two cases and discuss the pathophysiology of such hemorrhage and histopathological changes in thinned hyalinised vessels of this tumor. CONCLUSION: The presence of calcifications in the peri-hemorrhagic areas and the presence of mass effect disproportionate to the size of the bleeding are harbingers of the presence of a benign neoplasm that may have bled.

Centrifugal opening of dura for total extirpation of large convexity meningiomas: modifying the "classic" technique to prevent injury to the adjacent brain and veins.

BACKGROUND: Traditionally, the dura is opened along the margin of a convexity meningioma, jeopardizing the adjacent herniating brain and compressed veins in case of large meningioma. In this work, we describe a technique to open the dura centrifugally over convexity meningiomas. METHODS: Fifteen cases of large convexity meningiomas were operated on using the new technique. In our technique, the involved dura over large convexity meningiomas was opened in a centrifugal manner just short of the tumor-brain interface. The tumor was decompressed while preserving the arachnoid. The involved dura, along with the cuff of adjoining normal dura, was cut after tumor excision. RESULTS: Gross total excision could be achieved in all cases without any added deficits. There was arachnoid breach in three patients with insignificant venous injury in one. The preoperative symptoms improved in all. CONCLUSIONS: In this technique, the dura provides a natural barrier to protect the adjacent compressed brain and veins, thus avoiding handling the compressed adjacent neurovascular structures during surgery for large convexity meningioma without compromising the extent of resection.

Multiple intradural spinal metastases of esthesioneuroblastoma: A case report.

Spinal metastases from esthesioneuroblastoma (ENB) might have variable presentations. Discrete lesions, even when multiple, warrant radical excision, followed by radiotherapy. The authors present a case of anterior skull base ENB, metastasizing to spine at muliple levels. Clinical and radiological pictures are described with intraoperative findings.

Unusual imaging finding of a "fluid-fluid" level in a neurenteric cyst at anterior margin of the cervico-medullary junction.

Intracranial neurenteric cysts are rare. Diagnosis can only be established on histopathology with the demonstration of mucin-secreting cells in cyst wall. We report a midline, ventral, cystic lesion at the cervico-medullary junction, with the unusual radiological finding of a "fluid-fluid" level. Intraoperatively, the cyst contained fluid along with pus-like material with white flakes and specks of calcification, suggesting a dermoid cyst. However, histopathology confirmed the diagnosis of neurenteric cyst. The patient was managed with right lateral inferior suboccipital approach and near-total excision of the lesion.

Factors influencing feasibility of direct posterior reduction in irreducible traumatic atlantoaxial dislocation secondary to isolated odontoid fracture.

INTRODUCTION: Direct posterior reduction by intraoperative manipulation of joints for irreducible traumatic atlantoaxial dislocation (IrTAAD) has gained acceptance in the recent past. However, factors determining its feasibility have not been elucidated. Our study aims to examine the clinico-radiological factors predicting feasibility of direct posterior reduction in IrTAAD secondary to isolated odontoid fracture, in an attempt to differentiate the "truly irreducible" from those "deemed irreducible." MATERIALS AND METHODS: The onset and progression of neck pain and myelopathy was studied in 6 patients of IrTAAD with fracture odontoid, which failed to reduce despite traction. The dynamic X-rays and computed tomography (CT) scans of craniovertebral junction, along with the vertebral artery angiogram were studied to look for the slightest mobility, interface of fractured fragments, malunion, callous, and relationship of the C1-2 facets and vertebral artery. RESULTS: All 6 patients had progressive worsening of neck pain. Three patients had progressive myelopathy. Three patients presented 6 months after trauma. Radiology showed type-II fracture with IrTAAD (anterolisthesis in 5 and retrolisthesis with lateral dislocation in 1) and locked facets in all. X-rays showed doubtful callous formation in 3 patients and CT confirmed non-union. Three patients showed angular movement on dynamic X-rays despite irreducibility and locked facets. Angiogram showed thrombosis of vertebral artery in one patient. Intraoperative reduction could be achieved in all 6 patients with good clinico-radiological outcome. CONCLUSION: Worsening pain, progression of myelopathy, some movement on dynamic X-rays, a malunion ruled out on CT scan, and the presence of locked facets make direct posterior reduction feasible in patients with IrTAAD. The difficulty increases in remote fractures due to fibrosis around the dislocated joints. The role of the CT angiogram, in defining the relationship of Vertebral artery (VA) to the dislocated facets, and in determining the extent of VA injury, is vital. Preoperative detection of VA injury reduces the chance of intraoperative reduction, especially if only unilateral joint approach is planned.