Breaking Barriers for Cerebrospinal Fluid Flow in Chiari Malformation Type I: “What and How Much Is Enough?” A Retrospective Analysis of 74 Cases

Abstract

Introduction: Chiari malformation type I is a collection of hindbrain abnormalities, for which natural history of the disease process is not clear. The challenge is to identify which patients will benefit most from posterior fossa decompression. Objectives: To identify important surgical implications that most likely benefit patients with Chiari malformation type I by analyzing and reviewing various operative interventions in these patients with appropriate symptoms and then following their course. Subjects & Methods: Retrospective analysis of 74 operated Chiari malformation type I with syrinx adult patients was done. Results: No definite pattern of progression in natural history of disease was noted. Most of the patients who were symptomatically stable for months to years presented with recent rapid progression. The most common symptom was suboccipital pain. The most common finding was lower extremity weakness. On clinical presentation basis, patients were divided into three categories: foramen magnum compression syndrome, central cord syndrome, and cerebellar syndrome. Most patients in our study fall in first category. Foramen magnum decompression with atlas posterior arch removal and sometimes partial C2 laminectomy depending on extent of tonsillar descent as well as augmentation duraplasty was done in most patients. Improvement was seen in foramen magnum compression syndrome group more significantly. Conclusions: Individualized surgical techniques for breaking the barriers of cerebrospinal fluid (CSF) flow in Chiari malformation type I with syrinx to restore normal CSF dynamics across craniocervical junction provide the pragmatic solution. The trend is toward balance between optimum wide decompression as compared with long craniocaudal decompression and preserving normal integrity.