Occipital Interhemispheric Transtentorial Approach for Tumors of Posterior Third Ventricular Region: Review of Surgical Results.

Background: Controversies exist regarding the ideal surgical approach for tumors in posterior third ventricular region (PTV). Objective: To evaluate the results of occipital interhemispheric transtentorial (OITT) approach for tumors in PTV. Materials And Methods: Thirty-three patients underwent surgery via OITT approach for PTV tumors at Sri Sathya Sai Institute of Higher Medical Sciences during the study period of 5 years (June 2011-May 2016). Ideal trajectory for OITT approach was determined by neuronavigation. Endoscope was used for removing any residual lesion at the blind spots. Results: Postoperative magnetic resonance imaging (MRI) performed in all the patients revealed gross total or near-total (>95%) excision of tumor in 31 patients (93.9%). Preoperative neurological deficits improved either completely or significantly following excision of the tumor in 73.3% (11/15) of the patients. Outcome was good (modified Rankin scale ≤2) at discharge in 93.9% (31/33) and at a final follow-up of 3 months or more in 96.8% (30/31) of the patients. None of the patients died during the postoperative period. Complications included upgaze palsy (transient- 6.1% [2/33], persisting- 3% [1/33]), visual field defects (transient- 3% [1/33], persisting- 3% [1/33]), transient third nerve paresis (1/33-3%), transient hemiparesis (1/33-3%), operative site hematoma (1/33-3%), small posterior cerebral artery (PCA) territory infarct (1/33-3%), and small venous infarct (1/33-3%). At least one follow-up MRI could be performed in 23 patients. Final follow-up MRI revealed no recurrence or increase in the size of the residual lesion compared to postoperative images in 20 patients (20/23-87%) and large recurrence in 3 patients (3/23-13%) with high-grade lesions. Conclusion: Gross total/near-total excision can be performed in majority of the PTV tumors through OITT approach with minimal morbidity and mortality.

Outcome of Surgery for Congenital Craniovertebral Junction Anomalies with Atlantoaxial Dislocation/Basilar Invagination: A Retrospective Study of 94 Patients.

OBJECTIVE: To evaluate the results of surgery for congenital craniovertebral junction (CVJ) anomalies with atlantoaxial dislocation (AAD)/basilar invagination (BI) and compare the results of transoral odontoidectomy and posterior fusion (TOO+PF) with only posterior fusion (PF) in patients with irreducible AAD/BI. METHODS AND RESULTS: All 94 patients with congenital CVJ anomalies with AAD/BI operated on during the 3-year study period (June 2013-May 2016) were included. Of these patients, 55 had irreducible AAD/BI and the remaining 39 had reducible AAD/BI. TOO+PF was restricted to patients (34/94; 36.2%) with irreducible AAD/BI when reduction and realignment by intraoperative C1-C2 facet joint manipulation were considered technically difficult and risky. The remaining patients with irreducible AAD/BI and all the patients with reducible AAD/BI (60/94; 63.8%) were managed with only posterior fusion. Poor preoperative Nurick grade, preoperative dyspnea/lower cranial nerve deficits, and syringomyelia were associated with significantly higher incidence of postoperative pulmonary complications. Follow-up ≥3 months (final follow-up) was available for 87 patients. Good outcome (Nurick grade 0-3) at final follow-up was noted in 90% (45/50) of the patients with irreducible AAD/BI and 91.9% (34/37) of the patients with reducible AAD/BI. Preoperative poor Nurick grade (4-5) was the only factor associated with poor outcome. No significant difference in perioperative complications, outcome, and fusion was noted between patients who underwent TOO+PF or only PF for irreducible AAD/BI. CONCLUSIONS: Many of the patients with congenital AAD/BI showed remarkable recovery after surgery. Preoperative poor Nurick grade (4-5) is associated with poor outcome. TOO+PF is a safe alternative treatment option for irreducible AAD/BI when only PF techniques are technically difficult/risky.

Fatal holocord recurrence of a pregnancy-related, low-grade spinal ependymoma: case report and review of an unusual clinical phenomenon.

INTRODUCTION: Pregnancy-related spinal tumors (PRSTs) are unusual tumors that present during pregnancy or within a year after delivery. We describe a fatal holocord recurrence of a spinal ependymoma, which, to the best of our knowledge, is one of the most extensive PRSTs reported thus far. CASE PRESENTATION: A 21-year-old primigravida presented at 6 months of gestation with urinary incontinence for 2 months and spastic paraparesis for 1 month. MRI showed a conus intramedullary lesion from T10 to 12. Near-total resection of the lesion was performed. The histopathological diagnosis was that of a cellular ependymoma (WHO grade II). The patient presented 6 months later with progressive quadriparesis and breathing difficulty. MRI demonstrated holocord recurrence of the tumor with edema extending to the pontomedullary junction. The patient succumbed to respiratory failure before decompression of the tumor could be performed. DISCUSSION: This case highlights an unusual clinical course of a pregnancy-related, low-grade spinal ependymoma. The possible hormonal and genetic mechanisms underlying the aggressive involvement of the entire spinal cord by the recurrent tumor are discussed in the light of a literature review. Future studies may shed light on the possibility of utilizing these mechanisms as therapeutic targets to alter the clinical course of aggressive spinal ependymomas.

Far lateral approach without occipital condylar resection for intradural ventral/ventrolateral foramen magnum tumors and aneurysms of V4 segment of vertebral artery: Review of surgical results.

BACKGROUND: Controversies exist regarding the need and extent of condylar resection for safe surgical management of intradural ventral/ventrolateral foramen magnum (VFM) tumors and aneurysms of V4 segment of vertebral artery (VA) by far lateral approach. This retrospective study was conducted to evaluate the results of basic far lateral approach(retrocondylar approach) without upfront occipital condylar resection. METHODS AND RESULTS: Twenty one patients underwent surgery via far lateral approach for intradural VFM tumors and aneurysms of V4 segment of VA at Sri Sathya Sai Institute of Higher Medical Sciences during 9 years(2008-2016) study period. Eight patients had VA aneurysms and 13 patients had intradural VFM tumors. After basic far lateral approach(retrocondylar approach), dura was opened and checked if the exposure was adequate for safe surgery. Retrocondylar approach provided adequate exposure for all these lesions and resection of occipital condyle/jugular tubercle was not required in any of these cases. Skeletonization or transposition of VA was not done in any of these cases. Gross total resection of the tumor could be done in 9 patients(9/13-69.2 %) and near total excision (>95 %) in 4 patients (4/13-30.8 %). Seven of the 8 VA aneurysms were successfully clipped. Outcome at a final follow up of 3 months or more was good(mRS<2) in 19 patients(19/21-90.5 %) and poor in 2 patients. Complications included lower cranial nerve deficits [transient-2/21(9.5 %), persisting-2/21(9.5 %)], motor deficits(2/21-9.5%), seventh nerve paresis(1/21-4.8%), sixth nerve paresis(2/21-9.5%) and pseudomeningocele(1/21-4.8%). CONCLUSION: Basic far lateral (retrocondylar) approach provides excellent exposure for majority of VFM tumors and aneurysms of V4 segment of VA. Condylar resection(transcondylar approach), drilling of jugular tubercle (transtubercular approach), skeletonization/transposition of VA might not be required for safe surgical management of majority of these lesions.

Outcome of Microsurgical Clipping for Multiple Versus Single Intracranial Aneurysms: A Single-Institution Retrospective Comparative Cohort Study.

OBJECTIVE: To evaluate the results of microsurgical clipping for single intracranial aneurysm (SIA) and multiple intracranial aneurysms (MIA) and compare the outcomes. METHODS: All patients who underwent surgery for intracranial aneurysm (IA) at our institution over a 3-year period (June 2013 to May 2016) were included in this study. RESULTS: A total of 157 patients with 225 IAs were included. Forty-one of these patients had MIA (109 IAs, mean, 2.7 ± 1.2; range, 2-7), and remaining 116 had SIA. In the patients with MIA, all aneurysms were secured during the same admission whenever possible. Depending on the locations of the IAs and condition of brain during surgery (tense/lax), all aneurysms were secured on same day (in a single session, single or multiple craniotomy in 28 patients) or on different days (multiple sessions in 13 patients). Postoperative control angiography (DSA) before discharge could be done for 216 aneurysms (MIA, n = 105; SIA, n = 111). Successful occlusion of the aneurysm from circulation was noted in 96.2% (101/105) of MIA and 93.7% (104/111) of SIA. Follow-up of 6 months or longer was available for 146 patients. A modified Rankin Scale score ≤2 was considered a good outcome. Univariate analysis of the entire group revealed no significant difference in clinical outcomes between patients with SIA and MIA both at discharge (good outcome: MIA, 82.9%; SIA, 93.1%; P = 0.068) and at a final follow-up of ≥6 months (good outcome: MIA, 87.2%; SIA, 94.4%; P = 0.164). Clipping for MIA was not associated with poor outcome in multivariate analysis. CONCLUSIONS: Comparable clinical outcomes and high rates of complete aneurysm occlusion following microsurgical clipping can be expected in patients with SIA and patients with MIA.

Microsurgery for Spetzler-Martin Grade I-III Arteriovenous Malformations: Analysis of Surgical Results and Correlation of Lawton-Young Supplementary Grade and Supplemented Spetzler-Martin Score with Functional Outcome.

OBJECTIVE: To analyze the results of microsurgery for Spetzler-Martin (SM) grade I-III AVMs and evaluate the correlation of the Lawton-Young (LY) supplementary grade, supplemented Spetzler-Martin (SM-Supp/combined) score with the functional outcome. METHODS: A total of 42 patients with SM grade I-III AVMs who had undergone surgery at our institute during a 3-year period (June 2013 to May 2016) were included in the present study. RESULTS: All 42 patients had undergone primary surgery without previous embolization. Three patients (7.1%) had died due to surgical site hematoma in the postoperative period. One patient was lost to follow-up. The mean follow-up period for the remaining patients was 27 ± 14 months (range, 12-62 months). At the final follow-up examination of ≥12 months (FFU), 92.7% of the patients had a good outcome (modified Rankin scale [mRS] score ≤1), with an improved or unchanged mRS score in 87.8%. An AVM size >3 cm, diffuse AVM, SM grade III, and SM-Supp score >5 were associated with worsened mRS score at discharge and FFU. Higher LY grade (IV and V), eloquent AVM location, deep venous drainage, age >40 years, and unruptured presentation were not associated with worsened mRS score at both discharge and FFU. Of the 20 ARUBA-eligible patients, 19 (95%) had good outcomes. Postoperative angiograms for 39 patients revealed complete excision of the AVM in 37 (94.9%) and a residual AVM in 2 (5.1%). CONCLUSIONS: High cure rates and excellent clinical outcomes can be expected with microsurgery for most patients with SM grade I-III AVMs. An AVM size >3 cm, diffuse AVM nidus, SM grade III, and SM-Supp score >5 are associated with postoperative worsening of functional scores in patients with SM grade I-III AVMs.

Sellar-Suprasellar Paraganglioma: Report of 2 Cases and Review of Literature.

BACKGROUND: Intracranial paragangliomas are infrequent and those occurring in the sellar-suprasellar region are rare, with only 31 cases described in literature. CASE DESCRIPTION: We describe 2 cases of sellar-suprasellar paragangliomas in the light of a literature review. The first patient was a 13-year-old boy who presented with an intensely enhancing lesion in the sellar-suprasellar region with multiple flow voids within. Resection of the lesion was limited to a biopsy in view of its hypervascular nature. A second attempt at resection following partial embolization of the lesion was also unsuccessful. The tumor showed progressive reduction in size following radiotherapy. The second case was a 20-year-old man who presented with a similar tumor in the same location. He also had a probable metastatic deposit in the foramen of Magendie. An attempted surgical resection of the suprasellar lesion was abandoned after a biopsy. The patient improved symptomatically after radiotherapy. CONCLUSIONS: We report 2 cases of paraganglioma occurring in a rare location. Presence of flow voids within tumors in the sellar-suprasellar location should alert the surgeon to this entity. The hypervascular nature of these tumors may limit the extent of resection. In cases of inadequate tumor decompression, or if there is evidence of growth of residual tumor, radiotherapy can help to stabilize the disease.

Adenosine-Induced transient asystole during surgical treatment of basilar artery aneurysms.

AIM: To evaluate the safety and efficacy of adenosine-induced transient asystole (AITA) during surgery for basilar artery aneurysms. MATERIALS AND METHODS: All the patients with basilar artery aneurysms operated using AITA at our institute during two years period (August 2013-July 2015) were included in this study. RESULTS: Adenosine was used in 11 patients with 13 basilar artery aneurysms. Seven of these aneurysms were basilar bifurcation aneurysms, four were basilar-superior cerebellar artery junction aneurysms, and two were distal basilar trunk aneurysms. The indications for AITA were narrow corridor for placement of temporary clip in 11 aneurysms, intraop rupture in 1 aneurysm, and circumferential dissection of a large aneurysm in 1. The mean dose of adenosine used for inducing asystole was 19.4 mg (range: 15-30 mg) and the mean total dose of adenosine used was 40.6 mg (range: 18-90 mg). A mean of 2 (range: 1-5) AITAs were required during surgical treatment of these aneurysms. The mean duration of a systole was 27 s (range: 9-76 s). There were no complications related to AITA in these patients except for transient rebound hypertension in one patient. Check angiogram revealed complete obliteration of 11 aneurysms and small residual neck in 2 aneurysms. Modified Rankin Scale at three months of follow-up was 0 in seven patients, 1 in two patients, 4 in one patient, and 6 in one patient. CONCLUSION: AITA during surgical management of basilar artery aneurysms is a safe and effective technique and has an important role during surgery for these aneurysms.

Intradural "limited drill" technique of anterior clinoidectomy and optic canal unroofing for microneurosurgical management of ophthalmic segment and PCOM aneurysms-review of surgical results.

To evaluate the safety and efficacy of intradural "limited drill" technique (ILDT) of anterior clinoidectomy (AC) and optic canal unroofing (OCU) for microneurosurgical management of ophthalmic segment and posterior communicating artery (PCOM) aneurysms. All the patients with ophthalmic segment and PCOM aneurysms who underwent AC and OCU by ILDT for microneurosurgical management of ophthalmic segment and PCOM aneurysms during 4-year period (2013-2016) at our Institute were included in this study. In ILDT of AC and OCU, the use of power drill is restricted to AC only and OCU is done exclusively with 1-mm Kerrison punch. AC and OCU by ILDT were done in 24 patients with 29 ophthalmic segment and 7 PCOM aneurysms. AC and OCU by ILDT helped in mobilization of optic nerve/internal carotid artery (ICA) and provided excellent exposure for all these aneurysms. There was no injury to ICA or optic nerve during drilling. AC and OCU facilitated clip ligation of 34 of these aneurysms. Remaining 2 aneurysms were considered not suitable for clipping. Check angiogram done for 33 aneurysms revealed complete obliteration of 26 aneurysms, very small residual neck in 5 aneurysms, and small residual aneurysm in 2 aneurysms. Deterioration in vision was noted in 1 patient (4.1%). In 6 patients with preoperative visual deficits, significant improvement in vision was noted in 4 patients (4/6-66.6%) after surgery. Good outcome (MRS < 2) was noted in 91.6% (22/24) of these patients. ILDT is a safe and effective technique of AC and OCU which provide good exposure for ophthalmic segment and PCOM aneurysms.

Aggressive Primary Pediatric Intracranial Malignant Melanoma: Sphinx of the Tissue Diagnosis.

It is often intriguing to suspect and confirm the diagnosis of primary malignant melanoma (PMM) in the brain without any evidence of neurocutaneous melanosis. We report a 16-year-old male patient with malignant melanoma which intraoperatively was small sized, soft, fleshy, hemorrhagic in appearance resembling hematoma. Interestingly, the histopathology showed prominent papillary architecture with a differential diagnosis of papillary meningioma and ependymoma and perplexed the tissue diagnosis. This case is discussed in light of very uncommon occurrence of intracranial PMM in pediatric age group, enigmatic histological features, and aggressive nature of lesion with rapid progression despite complete excision following radiation therapy.

Safety and Accuracy of Anatomic and Lateral Fluoroscopic-Guided Placement of C2 Pars/Pedicle Screws and C1 Lateral Mass Screws, and Freehand Placement of C2 Laminar Screws.

OBJECTIVE: To evaluate the safety and accuracy of anatomic- and lateral fluoroscopic-guided placement of C2 pars/pedicle, C1 lateral mass screws, and freehand placement of C2 laminar screws. METHODS: All the patients who underwent posterior cervical/occipitocervical fixation that involved the placement of C1/C2 screws during a 5-year period (2011-2015) at our institute were included in this study. RESULTS: C1/C2 screws were placed in a total of 94 patients during this period. A total of 97 C1 lateral mass, 49 C2 pars, 24 C2 pedicle, and 82 C2 laminar screws were placed in these patients. C1 lateral mass screws and C2 pars/pedicle screws were placed under anatomic and lateral fluoroscopic guidance. C2 laminar screws were placed by a freehand technique. The mean length (range) of various C2 screws was 16.4 ± 2.6 mm (12-22 mm) for pars screws, 18.8 ± 2.7 mm (14-24 mm) for pedicle screws, and 25.6 ± 3.4 mm (18-32 mm) for laminar screws. Postoperative CT imaging done in all patients before discharge revealed malposition of 2 laminar screws with breach of the inner cortex. The position of the remaining C1/C2 screws was perfect. The superior and medial angulation of the pars screws and superior angulation of the pedicle screws as measured in postoperative CT images were found to significantly deviate from the angles described in the literature. There was no mortality, vertebral artery injury, or neurologic injury related to C1/C2 screw placement in this series. CONCLUSIONS: Anatomic and lateral fluoroscopic-guided placement of C2 pars/pedicle screws and C1 lateral mass screws and freehand placement of C2 laminar screws is extremely safe.

Management Issues in a Case of Congenital Craniovertebral Junction Anomaly with Aberrant Retropharyngeal Midline Course of Bilateral Cervical Internal Carotid Arteries at C1-C2.

BACKGROUND: Aberrant medial retropharyngeal prevertebral course of the internal carotid arteries (ICAs) is extremely uncommon. In oropharyngeal surgeries, like transoral odontoidectomy (TOO), this unrecognized aberrant retropharyngeal course of ICAs can result in devastating complications secondary to inadvertent injury of ICAs. We describe this aberrant course of ICAs in a patient with a craniovertebral junction (CVJ) anomaly with a dysmorphic C1 lateral mass on one side and discuss in detail various management issues in this complex case. CASE DESCRIPTION: A 44-year-old patient presented with neck pain, paresthesia in all 4 limbs, and quadriparesis. Computed tomography (CT) of the CVJ revealed os odontoideum, basilar invagination, atlantoaxial dislocation (AAD), severe malalignment of the C1-C2 facets, and an unusually thin (dysmorphic) left C1 lateral mass. Computed tomographic angiography revealed an aberrant medial retropharyngeal course of the bilateral cervical ICAs with near midline location at the level of C1 and C2. Transoral odontoidectomy (TOO) was not considered safe in view of potential injury to medially located ICAs. Normal spinal alignment with reduction of BI and AAD was achieved by C1-C2 joint distraction with placement of a spacer only in the right C1-C2 joint space followed by occipitocervical fusion. The patient experienced complete recovery after surgery with improvement of power in all 4 limbs to 5/5. CONCLUSIONS: Identification of this rare aberrant prevertebral course of ICAs in a patient with a CVJ anomaly is critical because it precludes TOO as a treatment option. Correction of BI and AAD is possible even with a unilateral C1-C2 joint spacer when placement of a joint spacer on the other side is not technically feasible.

Clinicopathological and imaging features of lipoastrocytoma: Case report.

Lipidized tumors of the central nervous system are very uncommon, with only a few cases described. We report a case of a 25-year-old woman with a tumor involving the left premotor area. She underwent gross total excision. Histologically, the tumor was composed of glial fibrillary acidic protein-positive glial cells with areas of lipidization. A diagnosis of lipoastrocytoma was rendered. At three-year follow-up she was doing well, supporting the presumed favorable prognosis of these uncommon tumors. Absence of xanthochromic appearance, mitotic activity, necrosis and poor reticulin activity are the differentiating features from the pleomorphic xanthoastrocytoma. We highlighted that these tumors involve the adult and pediatric population and distribute in both supratentorial and infratentorial compartments as well as in the spinal cord.

Routine placement of subdural drain after burr hole evacuation of chronic and subacute subdural hematoma: a contrarian evidence based approach.

The objective of this paper was to evaluate whether available evidence supporting placement of subdural drain placement after evacuation of chronic subdural haematoma (CSDH) is applicable to a cohort of patients managed by us. In this observational cohort study, clinical follow-up was obtained in 166 patients who underwent burr hole evacuation of CSDH without placement of subdural drain followed by 3 days of bed rest. The primary outcome studied was recurrence requiring reoperation. Factors predicting recurrence were also analysed. We compared the patient characteristics and management protocols in our cohort with that in reports supporting drain placement to determine whether such evidence is relevant to our patient group. The mean age of our patients was 58 ± 17 years (range, 1 to 89 years). Sixteen of the 166 (9.6%) patients presented with symptomatic recurrence. The median time to reoperation for recurrence (15 of 16 patients) after the primary procedure was 17 days (range, 2 to 68 days). Antiplatelet and anticoagulant therapy was the only factor that was significantly associated with recurrence (p = 0.01). There were no infective or non-infective complications in our patient cohort. Our patient cohort and outcomes differed from those reporting drain placements in the following parameters: they were a decade younger, all patients received bed rest for 3 days after surgery and the recurrence rate was similar to that reported in the drained groups but significantly less than that reported in the non-drained groups. Routine placement of drain following burr hole evacuation of CSDH should only be done after careful comparison of the patient cohort under consideration and those reporting superior outcomes with drains. Evidence-based medicine supports such an approach.

A points-based algorithm for prognosticating clinical outcome of Chiari malformation Type I with syringomyelia: results from a predictive model analysis of 82 surgically managed adult patients.

OBJECTIVE Although various predictors of postoperative outcome have been previously identified in patients with Chiari malformation Type I (CMI) with syringomyelia, there is no known algorithm for predicting a multifactorial outcome measure in this widely studied disorder. Using one of the largest preoperative variable arrays used so far in CMI research, the authors attempted to generate a formula for predicting postoperative outcome. METHODS Data from the clinical records of 82 symptomatic adult patients with CMI and altered hindbrain CSF flow who were managed with foramen magnum decompression, C-1 laminectomy, and duraplasty over an 8-year period were collected and analyzed. Various preoperative clinical and radiological variables in the 57 patients who formed the study cohort were assessed in a bivariate analysis to determine their ability to predict clinical outcome (as measured on the Chicago Chiari Outcome Scale [CCOS]) and the resolution of syrinx at the last follow-up. The variables that were significant in the bivariate analysis were further analyzed in a multiple linear regression analysis. Different regression models were tested, and the model with the best prediction of CCOS was identified and internally validated in a subcohort of 25 patients. RESULTS There was no correlation between CCOS score and syrinx resolution (p = 0.24) at a mean ± SD follow-up of 40.29 ± 10.36 months. Multiple linear regression analysis revealed that the presence of gait instability, obex position, and the M-line-fourth ventricle vertex (FVV) distance correlated with CCOS score, while the presence of motor deficits was associated with poor syrinx resolution (p ≤ 0.05). The algorithm generated from the regression model demonstrated good diagnostic accuracy (area under curve 0.81), with a score of more than 128 points demonstrating 100% specificity for clinical improvement (CCOS score of 11 or greater). The model had excellent reliability (κ = 0.85) and was validated with fair accuracy in the validation cohort (area under the curve 0.75). CONCLUSIONS The presence of gait imbalance and motor deficits independently predict worse clinical and radiological outcomes, respectively, after decompressive surgery for CMI with altered hindbrain CSF flow. Caudal displacement of the obex and a shorter M-line-FVV distance correlated with good CCOS scores, indicating that patients with a greater degree of hindbrain pathology respond better to surgery. The proposed points-based algorithm has good predictive value for postoperative multifactorial outcome in these patients.

Cervical En-Plaque Extradural Meningioma Involving Brachial Plexus.

BACKGROUND: Meningioma is one of the commonest spinal tumors, with a predilection for intradural occurrence. Its occurrence as an extradural, en plaque variety with extension into the brachial plexus is unusual. CASE DESCRIPTION: A 50-year-old male patient presented with progressive spastic quadriparesis. Magnetic resonance imaging showed an en plaque, epidural soft tissue tumor at C5-C7 levels on the right side with extraforaminal extension into the paraspinal region and the brachial plexus laterally. The patient underwent a C5-7 laminectomy and partial excision of the tumor. Histopathology was reported as psammomatous meningioma (World Health Organization grade I). CONCLUSIONS: An extradural spinal meningioma should be considered in the differential diagnosis of an exclusively extradural spinal tumor. Its occurrence as an en plaque variety is uncommon. We report an unusual case of the en plaque form of extradural cervical meningioma with diffuse involvement of the brachial plexus.

Pituitary apoplexy presenting as a peripheral rim enhancing parasellar mass lesion with dural enhancement along the tentorium.

Pituitary apoplexy is a potentially life-threatening clinical condition caused by rapid enlargement of a pituitary adenoma because of haemorrhage or infarction. The clinical features are typically acute in onset. We report an interesting case of 25-year-old man with complaints of sudden onset of headache and ophthalmoplegia in the right eye one month previously. He had ptosis and complete ophthalmoplegia in the right eye with visual acuity 6/24 and 6/12. Imaging showed a peripheral rim-enhancing mass lesion in the right parasellar and cavernous sinus with a dural tail. He underwent craniotomy and subtotal excision of the lesion. Histopathology was reported as pituitary apoplexy. Hormonal analysis was within normal limits. At two years of follow-up he had complete resolution of ophthalmoplegia and improvement in his vision. It is very uncommon to see pituitary apoplexy evolved in right parasellar region presenting as peripheral rim-enhancing mass lesion.

Giant multi-compartmental suprasellar Rathke's cleft cyst with restriction on diffusion weighted images.

Rathke's cleft cysts are congenital lesions seen in sellar-suprasellar regions. We report a case of giant Rathke cyst in a 43-year-old patient with multi-compartmental involvement who presented with seizures with almost normal visual acuity. We discuss radiological and pathological features of various differential diagnoses for the giant suprasellar Rathke's cyst.

Three-dimensional computed tomography angiographic study of the vertebral artery in patients with congenital craniovertebral junction anomalies.

PURPOSE: To describe vertebral artery (VA) course at the C0-C1-C2 complex in patients with congenital bony craniovertebral junction (CVJ) anomalies. METHODS: We studied the course of 169 VAs in 86 patients with congenital bony CVJ anomalies [basilar invagination (42), os odontoideum (33), and irreducible atlantoaxial dislocation (11)]. Occipitalized atlas occurred in 41 patients (30 complete and 11 partial). Using axial, coronal and sagittal three-dimensional computed tomography (3D-CT) angiograms, we traced the VA bilaterally at the CVJ and correlated the course to the presence or absence of occipitalization of the atlas. RESULTS: Of the 73 arteries associated with occipitalization of atlas, all had an abnormal course-58 (78.4 %) coursed through a canal within the C0-C1 fused complex and 15 (20.3 %) coursed below the C1 posterior arch, and it was absent unilaterally in one patient. There were 96 arteries associated with a non-occipitalized atlas and only 15 (15.3 %) were abnormal-eight coursed below the C1 posterior arch, four coursed above the C1 arch in the absence of a C1 foramen transversarium, one passed through a canal in C0-C1 and two arteries were absent unilaterally. Sixty vertebral arteries (34 on the right and 26 on the left side) had a redundant loop situated at a distance of ≥5 mm from the C1 lateral mass in patients with os odontoideum and irreducible atlantoaxial dislocation. CONCLUSIONS: In occipitalization of the atlas, the VA course is usually abnormal-typically passing through a canal within the C0-C1 fused complex or below the C1 arch. A redundant VA loop is more likely to be seen in os odontoideum and irreducible atlantoaxial dislocation. Careful study of the vertebral artery course with 3D CT angiography is mandatory while contemplating CVJ realignment surgery in congenital anomalies of the CVJ.