Histological findings in cerebellar tonsils of patients with Chiari type I malformation.
OBJECTIVES: Cerebellar tonsillectomy is often performed for relief of symptoms associated with Chiari type I malformation (CMI). Nonetheless, the idea of removing supposedly healthy central nervous tissue has been a source of concern for neurosurgeons. The aim of this paper is to determine the histological changes in the cerebellar tonsils of patients with a wide range of symptoms and conditions related to CMI. MATERIALS AND METHODS: The cerebellar tonsils of 43 pediatric patients with CMI were sent to pathology for histological examination. CONCLUSION: The cerebellar tonsils in a great majority of CMI patients can be abnormal. We suggest that the reported histological findings are secondary to injury and ischemia.