A computed tomography (CT)-based morphometric study of various skull base parameters and their anatomical relationships relevant to endoscopic endonasal skull base surgery.

Background: Endoscopic skull base surgery requires a thorough understanding of skull base anatomy. Orientation to regional anatomy to avoid complications like internal carotid artery injury can be assisted by knowledge of certain bony landmarks. These landmarks are themselves highly variable structures. This study focuses on the radiological morphometric characterization of these landmarks, which can be of great assistance to surgeons for better planning of endoscopic skull base approaches. Methods: Computed tomography scans of patients without skull base pathologies were analyzed retrospectively for the following parameters - Vidian canal (VC) length, VC and foramen rotundum (FR) distance from midline, the angle between the axis of VC and petrous internal carotid artery (pICA) and between VC and palatovaginal canal, the horizontal, vertical and direct distances between VC and FR and the patterns of sphenoid sinus (SS) pneumatization. Results: The VC-pICA angle was more obtuse and VC and FR were placed farther off the midline on the left as compared to the right side. Similarly, the distances between VC and FR were more on the left side. The VC length and distance of VC and FR from the midline were longer in males than in females. The VC-pICA angle was more obtuse in females. The post-sellar variant was the predominant pneumatization pattern seen (57.9%), and the incidence of lateral recess pneumatization was 15%. Conclusion: The results of our study can be utilized for a better understanding of the anatomy of the skull base. In skull base pathologies with distorted anatomical landmarks, a basic understanding of their interrelations can be used to have a better anatomical orientation. All these measures can help in avoiding complications and make extended endoscopic approaches safe.

The Displacement Patterns of Petrous Internal Carotid Artery and Its Morphometric Relations with Vidian Canal in Petroclival Chondrosarcomas Relevant to Extended Endoscopic Endonasal Approaches: A Radiological Study.

BACKGROUND: Extended endoscopic endonasal approaches (EEAs) to petroclival chondrosarcomas (PCs) require a thorough understanding of skullbase anatomy, especially the anatomy of petrous internal carotid artery (pICA), as ICA injury is the most dreaded complication of extended EEAs. We conducted this study to determine the displacement patterns of pICA in patients with PCs. METHODS: Contrast enhanced computed tomography scan and angiography images of patients with PCs were analyzed for following parameters-antero-posterior, cranio-caudal, medio-lateral, and direct distances between anterior genu of petrous internal carotid artery (AGpICA) and posterior end of Vidian canal (pVC). pICA encasement/narrowing by tumor was noted on magnetic resonance imaging. RESULTS: We studied 11 patients with histopathologically proven PCs. pICA encasement/narrowing and pVC destruction were observed in one patient each. The mean antero-posterior and cranio-caudal distances on tumor side/normal side were 7.7 ± 1.9/6.4 ± 1.0 mm & 4.5 ± 1.5/3.4 ± 0.9 mm, respectively. The overall displacement was posterior & superior. Medio-lateral displacement was seen in 4 patients (lateral in 3 and medial in 1). In rest, AGpICA was centered on pVC. The mean direct distance was 9.4 ± 2.5 mm. In 3 patients with displacement seen in all three axes, direct distance was measured by the "cuboid method." Overall, posterior-superior-lateral, posterior-superior, and anterior-inferior were the common displacement patterns of AGpICA relative to pVC. CONCLUSIONS: The displacement patterns of AGpICA in PCs are variable. An individualized approach with meticulous analysis of preoperative imaging can help in determining the relation between AGpICA and pVC. This detailed morphometric information can facilitate better orientation to altered anatomy, which can be helpful in preventing pICA injury during extended EEAs.

Papillary Tumors of Pineal Region: A Single-Center Experience in Management of 11 Cases.

BACKGROUND: Papillary tumors of pineal region (PTPR) comprise a very rare subset of pineal region tumors that have been recently described. Literature on the management and outcome of PTPR is scarce owing to the rarity of these tumors. To address this lacuna, we analyzed our experience in management of PTPR. METHODS: We retrospectively analyzed the outcome of 11 patients with histopathologically proven PTPR who underwent surgical excision at our center. RESULTS: Mean patient age was 33.3 years (range, 12-45 years), and male-to-female ratio was 1.75:1. Headache was the most common presentation followed by visual disturbances, altered sensorium, Perinaud syndrome, and seizures. Cerebrospinal fluid diversion was required in 6 patients. Krause approach was the most common approach used for tumor excision (9/11 cases). There was no perioperative mortality. Two patients were lost to follow-up. In the remaining 9 patients, the average follow-up period was 45 months (range, 12-79 months). On first postoperative magnetic resonance imaging, 8 patients showed no evidence of residual tumor (gross total resection), while 1 patient had small residual tumor (near-total resection) that remained stable during follow-up. Four patients underwent adjuvant chemoradiotherapy. None of the patients developed recurrence during follow-up. CONCLUSIONS: PTPR are a rare subgroup of pineal region tumors with distinct cells of origin but presentation similar to other pineal region tumors. Surgical resection constitutes the mainstay of management, and the extent of resection appears to be the most important determinant of prognosis. The role of adjuvant therapy still needs to be determined.

Non-chordomatous clival bony tumors: A rare experience and systematic literature review.

BACKGROUND: Non-chordomatous bony tumors of the clivus are extremely rare. Site, extent, and aggressiveness of tumor limits the extent of resection. It poses challenge to the neurosurgeons due to the complexity of anatomy. There is paucity of literature exclusively on non-chordomatous bone tumors of the clivus in young adults. OBJECTIVES: To analyze the clinical presentation, imaging findings, surgical approach, complications, and outcome of primary clival bony tumors in young adults. METHODS: We retrospectively reviewed children and young adults with primary clival bony tumors excluding chordoma who underwent surgical resection between years 2010 and 2023 in our center. We analyzed the demographic details, imaging findings, operative variables, perioperative complications, length of stay, complications, and outcome at latest follow-up. RESULTS: The mean age was 17.5 ± 1.73 years (range 16 to 19 years). Headache was the presenting complaint in all four patients (100%). The mean duration of symptom was 7.25 ± 3.2 months (range 5 to 12 months). The tumor was localized in clivus in all four patients (100%). The mean length of stay in hospital was 30.5 ± 13.48 days (range 11 to 40 days). All patients underwent surgical treatment. Surgical approaches used were anterior approach in four patients (100%). Gross total excision was performed in one patient (25%), sub-total excision was performed in two patients (50%), and tumor decompression was performed in one patient (25%). Of these, three were designated as having benign tumors and one had a malignant tumor. There was no perioperative mortality. There was one mortality (25%) on 2 months follow-up due to tumor progression. Three patients (75%) had improved symptomatically at latest follow-up. Two patients (50%) received adjuvant chemoradiotherapy. The mean follow-up was 38 ± 39.29 months (range 2 to 72 months). CONCLUSION: Non-chordomatous bony tumors of the clivus are rare and often underestimated. Surgery is the treatment of choice. Tumor consistency and adhesion to critical neurovascular structures precludes gross total resection. Various approaches are in the armamentarium. Approach to be decided based on the expertise of the neurosurgeon to achieve safe maximal resection. Multidisciplinary approach is mandatory for streamlined management. Adjuvant therapy is decided based on the residual tumor following surgery.

Posterior pedicle inferior turbinate flap for recurrent cerebrospinal fluid leak following endoscopic transsphenoidal surgery.

BACKGROUND: Adequate reconstruction of skull base following endoscopic transsphenoidal surgery is the most crucial step in reducing postoperative morbidity and mortality. Although, the success rate of traditional nasoseptal flap is very high, specific surgical scenarios preclude its use. A variety of vascularised endonasal and tunnelled scalp flaps have been described in the literature to address such situations. Posterior pedicle inferior turbinate flap (PPITF) is one such locally available vascularised flap. METHODS: Two patients with recurrent CSF leak following endoscopic transsphenoidal resection of pituitary adenoma were included. The nasoseptal flap was not available in both patients due to previous surgery. Hence, a PPITF based on the posterolateral nasal artery, a branch of sphenopalatine artery, was harvested and used for skull base reconstruction. RESULTS: In both patients, CSF leak subsided in the immediate postoperative period. In one patient, sensorium improved and was subsequently discharged in stable condition. Other patient succumbed to meningitis in the postoperative period. CONCLUSIONS: The PPITF is a valuable alternative to the conventional nasoseptal flap when the latter is not available and it is very important for an endoscopic skull base surgeon to be familiar with the technique of harvesting and using the PPITF.

Tadpole Sign in Filum Terminale Paragangliomas.

Two normotensive male patients came with complaints of low back pain. Contrast-enhanced magnetic resonance imaging of the lumbosacral spine revealed an enhancing intradural extramedullary lesion (at the L4-L5 vertebral level in the first patient and at the L2-L3 vertebral level in the second patient). The tumor resembled the head and caudal blood vessels the tail of a tadpole, thereby giving the "tadpole sign." This sign is an important radiologic and histopathologic correlate, which is helpful in preoperative diagnosis of spinal paraganglioma.

Comparison of Infection Rates Following Immediate and Delayed Cranioplasty for Postcraniotomy Surgical Site Infections: Results of a Meta-Analysis.

Postoperative surgical site infections (SSIs) in neurosurgery are rare. However, they pose a formidable challenge to the treating neurosurgeon and substantially worsen patient outcomes. These infections require prompt intervention in the form of débridement, including removal of craniotomy bone. Reconstruction of the craniotomy defect can be performed along with the débridement or can be performed at a later time. Although there have been concerns about performing cranioplasty at the same time as débridement, recent studies have advocated performance of cranioplasty at the same time as the débridement, as it avoids the morbidity associated with having a craniectomy defect and avoids the need for another surgical procedure. We conducted a literature review and meta-analysis to examine the data on immediate cranioplasties and delayed cranioplasties performed for postcraniotomy SSIs. We analyzed 15 articles with a total of 353 patients. Our analysis revealed that the pooled proportion of treatment failure was 10.4% (95% confidence interval [CI] 5.9%-17.8%) when an immediate cranioplasty was done and 16.1% (95% CI 7.2%-32.1%) when delayed cranioplasty was done. The pooled proportion of treatment failure was 12% (95% CI 5.9%-22.9%) when the same bone was used for cranioplasty and was 8% (95% CI 3%-20%) when prosthetic material such as titanium was used for cranial vault reconstruction. Thus, the rate of treatment failure was less when an immediate single-stage cranioplasty was done compared with a delayed cranioplasty following SSIs.

Single-Stage Posterior Only Approach for Unilateral Atlantoaxial Spondyloptosis with type-II odontoid Fracture in Pediatric Patients.

Objective: When there is a complete slippage of facet joints of C1 over C2 such that there is no contact between the articulating surfaces of C1 and C2, the condition is known as atlantoaxial spondyloptosis (AAS). AAS represents an extremely rare manifestation of atlantoaxial instability. This study was performed to highlight the presentation, radiological features, and management of unilateral AAS in pediatric patients. Material and Methods: We retrospectively identified four pediatric patients with AAS from our hospital records in the last 6 years (2014-2019). Results: Among the four patients with unilateral AAS, three were posttraumic and one was diagnosed with craniovertebral junction tuberculosis (CVJ TB). All the patients had a varying degree of spastic quadriparesis on presentation. One patient with CVJ TB presented with neck tilt. All patients with traumatic unilateral AAS were associated with an odontoid fracture. These patients underwent C1-C2 fixation with complete reduction of spondyloptosis using the techniques of joint manipulation and joint remodeling with a posterior only approach. Complete reduction of AAS in patients with trauma was also associated with the realignment of the odontoid fracture. All patients improved neurologically after surgery and achieved excellent correction of the deformity on a follow-up imaging. Conclusion: Pediatric unilateral AAS is an extremely rare phenomenon. A single-stage posterior approach with C1-C2 fixation is a feasible technique for the treatment of this seemingly difficult to correct deformity in pediatric patients and the clinical outcomes are excellent.

Management of Pediatric and Adolescent Traumatic Thoracolumbar Spondyloptosis.

Background: Complete subluxation of >100% of one vertebral body with respect to the adjacent vertebra is defined as spondyloptosis. It is the severest form of injury caused by high-energy trauma. Pediatric patients with a traumatic spine injury, particularly spondyloptosis are surgically demanding as reduction and achieving realignment of the spinal column requires diligent planning and execution. Objective: To enlighten readers about this rare but severest form of thoracolumbar spine injury and its management. Methods: Retrospective analysis of patients treated here with spondyloptosis between 2008 and 2016 was done. Results: Seven children, ranging from 9 to 18 years (mean years) age were included in the study. Five patients had spondyloptosis at thoracolumbar junction and one each in the lumbar and thoracic spine. All patients underwent single-stage posterior surgical reduction and fixation except one patient who refused surgery. Intraoperatively, cord transection was seen in five patients while dura was intact in one patient. The mean follow-up period was 17 months (1-36 months) during which one patient expired due to complications arising from bedsores. All patients remained American Spinal Injury Association (ASIA) A neurologically. Conclusions: Traumatic spondyloptosis is a challenging proposition to treat and the aim of surgery is to stabilize the spine. Rehabilitation remains the most crucial but the neglected part and dearth of proper rehabilitation centers inflict high mortality and morbidity in developing countries.

Intraventricular Pilocytic Astrocytoma: A Single Centre Experience.

Background: Intraventricular pilocytic astrocytomas are a rare occurrence, accounting for approximately 4% -15.6% of all pilocytic astrocytomas .The aim of the study was to describe the radiology, surgical management and outcome in 15 patients with histopathologically proven intraventricular pilocytic astrocytoma(IVPA). Objective: To study the clinical presentation radiology and operative challenges in rare intra ventricular pilocytic astrocytomas. Materials and Methods: Between January 2010 and August 2018, 15 patients with histopathologically proven IVPA were identified. The radiological images were obtained from PACS. Patient and surgical details were obtained from the computerized discharge summary, OT records and operative notes, whereas follow up was obtained from the record section. Results: Headache with progressive loss of vision was the most common presentation. Duration of symptoms varied from 4 months to 2 years (mean 9. 88 months). Except one patient, all patients with preoperative CT scan revealed calcifications in the lesion, with extensive calcification in 3 patients. All the tumors were predominantly hypointense on T1WI and iso to hyperintense on T2WI. Lesion in all patients showed heterogenous contrast enhancement on post gadolinium images. Mean blood loss in the series was 1969 ml (range 250 ml- 4500 ml).There was one death in this series due to meningitis and septic shock. Conclusion: IVPAs are rare tumors and are difficult to diagnose in the preoperative period based on the radiologic profile alone. These tumors can be extremely vascular with potential for massive blood loss. These tumors can be associated with extensive calcification and the calcified tumors have less bleeding as expected.

Suprameatal Extension of Retrosigmoid Approach in Microvascular Decompression for Trigeminal Neuralgia with Petrous Endostosis: Case Report and Literature Review.

Petrous endostosis or prominent suprameatal tubercle is a rare entity which may prevent adequate microscopic exposure of the trigeminal nerve root entry zone during microvascular decompression (MVD) for trigeminal neuralgia. We present a rare case of trigeminal neuralgia (TN) with petrous endostosis, which was managed adequately by partial removal of the prominent suprameatal tubercle to improve the obscured site of neurovascular conflict and enabled complete MVD. Through this manuscript, we additionally discuss the nuances involved in this extension of the standard retrosigmoid approach in light of the published literature. Petrous endostosis encountered during MVD for TN can impose an operative challenge. Suprameatal extension of the standard retrosigmoid approach improves exposure at the site of neurovascular conflict but requires utmost care and attention to avoid complications. We emphasize recognizing this anatomical variation in the preoperative period to predict an operative difficulty, ensure appropriate patient counselling, and avoiding surgical complications.

Use of Intraoperative Imaging to Preserve C1-C2 Mobility in Complex Atlas-Hangman Fractures.

Background: Combination fractures of the C1-C2 complex especially atlas and hangman are relatively uncommon and management usually compromises C1-C2 mobility. Objective: To evaluate the treatment of combined C1- hangman's fracture with and without intraoperative O- arm based navigation system, and its outcome in terms of preserving C1-C2 mobility. Methods: This was a case series of patients with combined C1 and hangman's fracture, managed at a tertiary care hospital during February 2009 to December 2016. Neurological function assessed with American Spine Injury Association (ASIA) impairment scale. Radiological fusion of the operated segment assessed with computed tomographic scan, criteria used for successful fusion included formation of callus across the fracture. Preservation of rotational motion between C1 and C2 was assessed by cervical flexion rotation (CFR) test. Results: We included 10 patients (male/female: 9/1; mean 47.7 ± 17.5 years) in our study. Operative intervention was performed in 9 patients. We used intraoperative computed tomogram (CT) scan with navigation in 5 patients. The mean follow-up period was 28.7 months (range 6 to 70 months). Neurological recovery occurred in all 4 patients with preoperative neurological deficits. Radiological fusion occurred in all cases. Rotation at C1-2 was preserved in all 5 cases operated under O-arm guidance and in one patient with type 1 fracture who was managed conservatively. Conclusions: The goals in treating these complex fractures are to achieve early maximum stability and preserving maximum range of motion. These are often competing phenomena, which can be achieved by using intra operative CT scan and navigation system.

Successful multimodality management of extrarenal extracranial malignant rhabdoid tumour of the left sciatic nerve mimicking a neurofibroma.

Extrarenal extracranial malignant rhabdoid tumour (MRT) is a rare and highly aggressive tumour representing <1% of paediatric soft tissue malignancies. Only a few cases of MRT of the thigh arising from the sciatic nerve have been reported in medical literature to date. A 5-year-old girl presented with progressively increasing painless lump in the posterior aspect of the left thigh. A contrast-enhanced magnetic resonance imaging (MRI) of the left thigh showed a 4.7 × 5 × 10.5 cm well-marginated, lobulated, homogeneously enhancing lesion in the posterior compartment of the left thigh along the course of the sciatic nerve. She underwent en bloc excision of the left sciatic nerve tumour and end-to-end anastomosis of the left sciatic nerve with a right sural nerve graft. Histopathological and immunohistochemical examination of the surgical specimen revealed a malignant rhabdoid tumour. INI-1 immunoexpression was lost in the tumour cells. The metastatic workup was essentially normal. Subsequently, she received post-operative radiotherapy to the tumour bed (50.4 Gray in 28 fractions over 5.5 weeks) followed by six cycles of multiagent chemotherapy with ICE (Ifosfamide, Carboplatin, and Etoposide) regimen. On the last follow-up visit, 20 months after surgery, she was in complete clinical and radiological response. Aggressive multimodality management comprising radical resection of tumour, post-operative radiotherapy to the tumour bed, and multiagent chemotherapy with ICE regimen can lead to favourable outcomes in patients with this rare tumour.

Management of Myelopathy due to Anterior Soft-Tissue Compression in Vertebral Hemangioma.

OBJECTIVE: Vertebral hemangiomas are benign but highly vascular lesions and are one of the most common lesions of the vertebral column. Anterior soft-tissue compression of spinal cord due to vertebral body hemangioma is challenging to manage. Our objective was to assess long-term clinical and radiologic effects of direct transpedicular absolute alcohol embolization, laminectomy, and short-segment instrumented fusion on resolution of extraosseous epidural soft tissue and improvement in myelopathy in cases of vertebral hemangioma causing anterior soft-tissue compression. MATERIALS AND METHODS: This was a retrospective analysis that included patients with single-level vertebral hemangioma with anterior intraspinal soft-tissue growth causing spinal cord compression and clinical features of myelopathy between June 2007 and June 2019 at authors' institute. Transpedicular vertebral body injection of absolute alcohol, laminectomy, and pedicle screw rod instrumentation was performed in all patients. Clinicoradiologic outcomes of surgery were noted. We proposed a grading system for the extent of anterior extraosseous epidural soft-tissue compression. RESULTS: In total, 14 patients were included in study. Their mean age was 28.4 ± 14.4 years. Mean follow-up duration was 67.5 ± 36.2 months. All patients had preoperative radiologic grade 4 compression. Postoperative radiologic grading improved to grade 1 in 4 (28.6%), grade 2 in 8 (57.1%), and grade 3 in 2 (14.3%). All the patients improved neurologically after surgery. Eleven patients improved to American Spinal Injury Association (ASIA) grade E, 2 improved to ASIA D, and 1 improved to ASIA C at the last follow-up visit. CONCLUSIONS: Vertebral hemangiomas with anterior extraosseous epidural extension causing spinal canal compromise and myelopathy can be managed with direct transpedicular ethanol embolization, laminectomy, and short-segment instrumented fusion with resolution of the extraosseous soft tissue and improvement in myelopathy. The procedure is relatively simple, cost effective, and has a good outcome.

Transpedicular Approach for Corpectomy and Circumferential Arthrodesis in Traumatic Lumbar Vertebral Body Burst Fractures: A Retrospective Analysis of Outcome in 35 Patients.

BACKGROUND: Traumatic vertebral burst fractures can be surgically approached via different approaches (anterior/posterior, or combined). Transpedicular approach (TA) is a posterior approach that has the advantage of achieving circumferential arthrodesis via single posterior only approach. The purpose of this study was to analyze our experience with TA in management of traumatic lumbar burst fractures (TLBFs). MATERIALS AND METHODS: All consecutive patients with TLBFs managed with TA over 5 years duration were included in this retrospective study. Correction of kyphotic deformity and change in neurological status were analyzed to assess outcome. Cobb's angle and ASIA grade were used for this purpose. RESULTS: There were 21 males and 14 females. Eight patients had complete (ASIA-A) while 22 had incomplete injury. All patients had a TLICS score >=4. The mean preoperative Cobb's angle was 13.97° that improved to -3.57° postoperatively (mean kyphosis correction-17.54°). None of the patients developed iatrogenic nerve root injury. There was no perioperative mortality. The mean cobb's angle was 1.23° at 39.1 months follow-up. Eight patients developed cage subsidence but none required revision surgery. Postoperatively, 27 (77.1%) patients showed neurological improvement and none deteriorated. The median ASIA score improved from 3 to 5. A fusion rate of 91.4% was observed at last follow-up. CONCLUSIONS: The advantages of TA including sense of familiarity with posterior approach amongst spine surgeons, lesser approach-related morbidity, and results comparable to anterior/combined approaches, make TA an attractive option for managing TLBFs. Although technically difficult, it can be successfully used for circumferential arthrodesis in lumbar region without sacrificing nerve roots.

Evolution to Pedicle Reformation Technique in Surgical Management of Hangman's Fracture.

BACKGROUND: Opinions vary regarding optimal treatment of unstable hangman's fractures. Recent technological advances have allowed short segment, motion preserving fixation, even in complex cases. The aim of the study was to demonstrate C1-C2 motion-preserving short-segment fusion in hangman's fracture and the evolution of technique from pedicle realignment to pedicle reformation in complex fractures with resorbed/destroyed C2 pedicles. METHODS: This was a retrospective study. Patients operated by a single surgeon at a tertiary level center from 2012 to 2018 were included. The type of fracture, operating time, and blood loss was recorded. Neurologic deficits were recorded using the American Spinal Injury Association scale with regular clinicoradiologic follow-up. RESULTS: Nine patients (8 male), with a mean age of 36 ± 16.9 years were included. In the initial 7 patients, C2 pedicle screw, C3-C4 lateral mass screw, and rod fixation was done. The last 2 patients were complex neglected injuries, with 1 having severe angulation and displacement and the other having spondyloptosis with C2 body placed anterior to C4 body. In both these patients, direct C2 body screw were placed and pedicle reconstruction was done. Mean follow up was 41.4 ± 29.8 months. All 5 patients with preoperative neurologic deficits had improvement in power. C1-C2 joint motion was preserved in all. All patients had bony fusion. CONCLUSIONS: Preservation of motion at the C1-C2 joint should be the goal in all surgically managed hangman's fracture patients. The technique of C2 pedicle reconstruction can be utilized for the same in old neglected hangman's fractures.

C19MC amplification and expression of Lin28A and Olig2 in the classification of embryonal tumors of the central nervous system: A 14-year retrospective study from a tertiary care center.

INTRODUCTION: CNS embryonal tumors (CET) other than medulloblastomas (MB) and atypical teratoid/rhabdoid tumors (AT/RTs), previously designated as 'central nervous system primitive neuroectodermal tumors' ('CNS PNETs'), are a heterogenous subset of tumors with poorly defined diagnostic criteria. Other than the subset of embryonal tumor with multilayered rosettes (ETMR) defined by C19MC amplification, most CETs are diagnosed by exclusion of other molecularly defined entities and histological mimics including MB, AT/RTs, and high-grade gliomas, and termed as CET, not otherwise specified (NOS) in the 2016 WHO classification. AIM: To reclassify 'CNS PNETs' as per WHO 2016, and estimate the true proportion of CET, NOS in a tertiary healthcare setting, and to evaluate the diagnostic utility of C19MC amplification, Lin28A and Olig2 expression in the subclassification of CETs. METHODS: Previously diagnosed cases of 'CNS PNETs' (2002-2016) were first evaluated by immunohistochemistry (IHC) for MIC2, RelaA, L1CAM, IDH1R132H, H3K27M, H3G34R, H3G34V, INI1, and BRG1 proteins and by fluorescence in-situ hybridization (FISH) for EWSR1 translocation to exclude histological mimics. The selected CETs (case cohort) and 79 histological mimics (comparison cohort) comprising of MB, AT/RT, pineal parenchymal tumors, Ewing sarcoma, esthesioneuroblastoma, intraocular medulloepithelioma, and H3G34R mutant high-grade glioma were subject to IHC for Olig2 and Lin28A, and FISH for C19MC amplification. RESULTS: Twenty-two cases of 'CNS PNETs' were retrieved, all of which were negative for the first panel of markers and showed retained INI-1/BRG1 expression. Three of them (3/22, 13.6%) showed C19MC amplification (ETMR, C19MC-altered) with ETMR histology, Lin28A positivity, and Olig2 negativity. Among the remaining 19 CETs, one showed medulloepithelioma histology (Medulloepithelioma, NOS) and remaining were non-descript small round cell tumors (CET, NOS), all negative for Lin28A. Olig2 was positive in only 3 CETs (13.6%), all being CET, NOS. All tumors in the comparison cohort were negative for C19MC amplification, Lin28A and Olig2 except for 27% of ATRTs that were Lin28A positive. CONCLUSION: ETMR, C19MC-altered constitute less than 14% of CETs, with majority remaining uncharacterized as CET, NOS. Lin28A is 100% sensitive for the detection of C19MC amplification; however, its specificity is limited by its expression in ATRTs. Olig2 expression is seen only in a small subset of CET, NOS and is of limited diagnostic utility.

Long-Term Outcome of Surgical Management in Symptomatic Pediatric Vertebral Hemangiomas Presenting With Myelopathy.

BACKGROUND: Vertebral hemangiomas are benign, highly vascular lesions of the vertebra, rarely seen in the pediatric age group. OBJECTIVE: To analyze the long-term (>3 yr) outcome of patients of pediatric vertebral hemangioma presenting with myelopathy and to describe our surgical strategy to treat such cases. METHODS: All patients up to 18 yr of age with a symptomatic vertebral hemangioma treated at our hospital from May 2003 to August 2016, with at least 3-yr follow-up were included. Functional clinical outcomes were measured using American Spinal Injury Association (ASIA) score. RESULTS: There were 7 male and 7 female patients. All hemangiomas were located in the thoracic spine with single-level involvement. Upper thoracic spine involvement was more common (12 cases: 85.71%) than lower thoracic spine involvement (2 cases: 14.29%). All patients had features of myelopathy. The mean age was 14.57 yr, ranging from 10 to 18 yr. The mean follow-up was 62.21 mo, ranging from 36 to 90 mo. All patients had improvement in motor strength of both lower limbs postoperatively. Local pain, which was present in 1 patient, resolved, and the bladder symptoms present in 5 patients also resolved. CONCLUSION: Our experience in treating symptomatic pediatric vertebral hemangiomas, along with the long-term follow-up data, suggests that good postoperative results can be achieved with minimal complications in carefully selected patients.

Parietal transventricular approach for medial temporal glioma: A technical report.

BACKGROUND: Medial temporal lobectomy (MTLy) poses a surgical challenge due to convoluted anatomy of medial temporal lobe (MTL). Various approaches have been described to access MTL for removing various pathologies. We, hereby, describe the parietal transventricular approach for removing a concurrent medial temporal glioma in a patient with recurrent parietal glioma. CASE DESCRIPTION: A 40-year-old female operated and diagnosed case of the right parietal anaplastic astrocytoma presented to us with a recurrence in parietal region. In addition, a fresh lesion was observed in the right MTL suggestive of a separate temporal glioma. The patient underwent excision of both parietal and temporal gliomas through the parietal approach only. Complete excision of parietal recurrence and near-total excision of medial temporal glioma was achieved. CONCLUSION: The parietal approach can be used for excision of medial temporal lesions, especially those involving or extending into its posterior limits. In the presence of concurrent parietal and MTL lesions, both lesions can be removed through a single parietal approach rather than a separate approach for MTLy. It offers additional advantages of the preservation of optic radiations as well as the temporal neocortex. The visual orientation of MTL structures is different when viewed from the parietal approach as compared to the temporal approaches. The parietal approach provides in line orientation of medial temporal structures contrary to the perpendicular orientation visualized in temporal approaches. An understanding of MTL anatomy as viewed from a parietal vantage point and its three-dimensional conceptualization is very important to successfully remove lesions of MTL through the parietal approach.

Intracranial Meningeal Hemangiopericytomas: An Analysis of Factors Affecting Outcome in 39 Cases Managed with Multimodality Treatment.

AIM: To retrospectively evaluate the outcome of patients with intracranial meningeal hemangiopericytomas (MHPCs) and to analyze various factors for recurrence and survival in these patients. MATERIALS AND METHODS: We retrospectively reviewed the clinical data of 39 patients undergoing microsurgical resection for MHPCs at our institute from 2009 to 2015. RESULTS: Gross total excision (GTE) was achieved in 27 (69.2%) patients, whereas 12 (30.8%) underwent subtotal excision (STE). A total of 25 patients received radiotherapy (RT) (Conventional RT-15; GKT-10), 21 patients had a low grade tumor, while 18 had an anaplastic variant. Twenty patients (51.3%) developed recurrences and the average recurrence-free survival (RFS) was 56 months (range: 12-180 months). Eight patients (20.5%) died during the study period. The average overall survival (OS) was 77.2 months (range: 36-192 months). Two patients (5.1%) developed systemic metastases during follow-up. Patient age was not found to affect RFS or OS. GTE was associated with prolonged RFS and OS but the impact was not statistically significant (P-values = 0.160 and 0.414, respectively). Low tumor grade was associated with statistically significant longer RFS as well as OS (P-values = 0.049 and 0.013, respectively). Addition of adjuvant RT was associated with statistically significant prolongation of RFS (P value = 0.016); however, it was not associated with statistically significant OS benefits (P-value = 0.758). CONCLUSIONS: Our study suggests that a greater extent of excision, lower tumor grade, and addition of adjuvant RT have a positive impact on both RFS and OS; however, low grade and adjuvant RT were the only factors associated with statistically significant prolongation of RFS and only tumor grade was associated with statistically significant OS benefits.