The Tissue Bank began collecting tissue from neurosurgical operations in 1978 and has established an organized repository of characterized tissues that have been collected and maintained in a manner useful for a wide range of studies. Copies of each patient’s consent to donate their tissue for research are maintained in a secure area of the Tissue Bank. Clinical data from each case are logged into a secured computer data base. Tissue received into the Tissue Bank is catalogued and referenced by a consecutive numbering system in order to maintain patients’ confidentiality.