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Central neurocytomas are rare intraventricular neoplasms of the central nervous system, compromising 0.25-0.5% of brain tumors. The diagnosis and management of these tumors remains controversial since most clinical series are small. Typically, patients with central neurocytomas have a favorable prognosis, but in some cases the clinical course is more aggressive. Although histological features of anaplasia do not predict biologic behavior, proliferation markers including MIB-1 might be more useful in predicting relapse. The most important therapeutic modality is surgery, and a safe maximal resection confers the best long-term outcome. In cases of a subtotal resection,'standard external beam radiation can be added or radiation can be delayed until tumor progression occurs. Smaller residual tumor volumes or recurrences can be treated with more conformal radiation or focused radiosurgery. Re-operation for recurrence should be considered if the procedure can be safely performed. Chemotherapy may be useful for recurrent central neurocytomas that cannot be resected and have been radiated, although long-term responses have not been reported for chemotherapy. Overall, this paper reviews the findings of the larger studies and highlights some of the important case reports that contribute to the current management of central neurocytomas.

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Two related inhibitors were flexibly docked into different conformers of aldose reductase. Although the overall binding topologies were roughly matched, significant deviations are observed in the subsequently determined crystal structures. Flexible redocking into the crystallographically observed protein conformers achieves, however, perfect binding‐position predictions.

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Release of tethered spinal cord by sectioning of the filum terminale carries a risk of injuring neighboring motor and sensory nerve roots involved in bowel and bladder control. Therefore, intraoperative neurophysiological monitoring techniques have been developed to prevent neurological complications postoperatively. We performed a retrospective chart review of 63 patients who had undergone tethered cord release. We excluded adult patients, those lost to follow-up and patients with either a myelomeningocele and/or lipoma. This limited our study to 25 pediatric patients, aged 4 months to 12 years, who underwent tethered cord release for either a thickened filum terminale and/or a low-lying conus. For intraoperative monitoring, we utilized electrical stimulation of the filum terminale, lumbosacral nerve roots and electromyography recordings. Ventral nerve roots were identified and their electrical thresholds obtained. The mean was 0.32 V, the mode 0.1 V and the range 0.05– 1.0 V. These values were compared to electrical thresholds obtained by stimulation of the filum terminale. The mean was 26.1 V, the mode 20.0 V and the range 8–100 V. In over 70% of patients, muscle activation via the filum required 100 times the voltage needed to activate a motor root. This motor root to filum threshold of 1:100 was useful in identifying the filum. Clinical outcome showed no significant worsening with respect to bowel and bladder control or pain and motor indices. Significant bowel and bladder improvement was seen in 4 out of 25 patients, motor improvement in 9 out of 25 patients and improvement of pain in 4 out of 25 patients. Three patients developed postoperative urinary tract infections, but no cerebrospinal fluid leaks or pseudomeningoceles were encountered. These results suggest that patients with a thickened filum or low-lying conus can safely undergo tethered cord release. Intraoperative neurophysiological monitoring provides a helpful adjunct to distinguish nerve roots from the filum. A ratio, rather than an absolute number, is beneficial in distinguishing motor roots from the filum and eliminates variability due to patients’ individual differences in electrical thresholds.

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