Utilization of frozen sections in the evaluation of chronic epilepsy-related cases

The role of frozen section consultation in the evaluation of chronic epilepsy-associated surgical excisions of brain tissue has not been previously examined. The study retrospectively reviews 335 cases in which a frozen section consultation was obtained in the setting of a resection for chronic epilepsy. In most cases (n = 323), 3 or fewer frozen sections were performed. The most commonly identified pathologies on final diagnosis included tumor or tumorlike lesions (79.1% of cases) and focal cortical dysplasia (20.9% of cases). Frozen section diagnoses discrepant with final diagnoses due to sampling error or misinterpretation were noted in 39 cases and most commonly involved a diagnosis of gliosis or tumor in the setting of a focal cortical dysplasia or diagnosis of gliosis in the setting of a low-grade tumor. In conclusion, frozen section consultation may be particularly useful in the evaluation of neoplasms arising in the setting of chronic epilepsy. Some epilepsy-associated pathology, such as focal cortical dysplasia, may be difficult to diagnose at the time of frozen section and such cases may not be an ideal target for intraoperative frozen section consultation.