Intracranial nonvestibular neurinomas: Young neurosurgeons' experience.

BACKGROUND AND OBJECTIVES: Neurinoma arising from other than nonvestibular cranial nerves is less prevalent. Here we present our experiences regarding the clinical profile, investigations, microneurosurgical management, and the outcome of nonvestibular cranial nerve neurinomas. MATERIALS AND METHODS: From January 2005 to December 2011, the recorded documents of operated nonvestibular intracranial neurinomas were retrospectively studied for clinical profile, investigations, microneurosurgical management, complications, follow-up, and outcomes. RESULTS: The average follow-up was 24.5 months. Total number of cases was 30, with age ranging from 9 to 60 years. Sixteen cases were males and 14 were females. Nonvestibular cranial nerve schwannomas most commonly originated from trigeminal nerve followed by glossopharyngeal+/vagus nerve. There were three abducent nerve schwannomas that are very rare. There was no trochlear nerve schwannoma. Two glossopharyngeal+/vagus nerve schwannomas extended into the neck through jugular foramen and one extended into the upper cervical spinal canal. Involved nerve dysfunction was a common clinical feature except in trigeminal neurinomas where facial pain was a common feature. Aiming for no new neurodeficit, total resection of the tumor was done in 24 cases, and near-total resection or gross total resection or subtotal resection was done in 6 cases. Preoperative symptoms improved or disappeared in 25 cases. New persistent deficit occurred in 3 cases. Two patients died postoperatively. There was no recurrence of tumor till the last follow-up. CONCLUSION: Nonvestibular schwannomas are far less common, but curable benign lesions. Surgical approach to the skull base and craniovertebral junction is a often complex and lengthy procedure associated with chances of significant morbidity. But early diagnosis, proper investigations, and evaluation, along with appropriate decision making and surgical planning with microsurgical techniques are the essential factors that can result in optimum outcome.

Endoscopic endonasal transsphenoidal exposure of circle of Willis (CW); can it be applied in vascular neurosurgery in the near future? A cadaveric study of 26 cases.

AIM: Endonasal transsphenoidal approaches are getting rapidly popular in removing many midline skullbase lesions from crista galli to foramen magnum. For safe removal of these lesions, familiarity with endoscopic endonasal anatomy of circle of Willis is very important. Furthermore, for safe development of this approach in vascular neurosurgery in the near future, endoscopic endonasal exposure of circle of Willis is a fundamental step. The goals in this study were to dissect the circle of Willis completely through the endoscopic endonasal approach and to become more familiar with the views and skills associated with the technique by using fresh cadaveric specimens. MATERIAL AND METHODS: After obtaining ethical clearance, 26 fresh cadaver heads were used without any preparation. Using a neuroendoscope, complete exposure of the circle of Willis was done endonasaly, and various observations including relation of circle of Willis was recorded. RESULTS: Complete exposure of the circle of Willis was made through an endonasal approach in all cases without injuring surrounding structures. CONCLUSION: Endoscopic endonasal extended transsphenoidal exposure of CW can make the surgeon more efficient in removing midline skullbase lesions with safe handling of different parts of circle of Willis and it may help in development of endonasal endoscopic vascular neurosurgery in the near future.

Pathological findings in cystic craniopharyngiomas after stereotactic intracavitary irradiation with yttrium-90 isotope.

Histopathological, ultrastructural and polyacrylamide gel electrophoretic examinations were carried out on biopsy, cyst fluid, surgical pathology and autopsy specimens obtained from 7 cystic craniopharyngioma cases before and after yttrium-90 silicate colloid (90Y) irradiation. Light microscopy revealed that the lining epithelial tumor cell layer of the cyst wall was destroyed, and scar tissue containing large amount of hyaline degenerated collagen bundles replaced it. Proliferative postirradiation vasculopathy was also demonstrated in the cyst wall following 90Y installation. Electrophoretic property of cyst fluid was similar to the normal human serum. Considering that scar tissue has a certain propensity to shrink, the fibrosis in the cyst wall together with destruction of neoplastic epithelium and vascular changes might explain diminished fluid production and cyst volume reduction after 90Y treatment.