Association of Posterior Fossa Morphometric Analyses with Cerebrospinal Fluid Flow Parameters in Patients with Chiari Malformation Type 1.

Abstract

Objectives: Chiari malformation (CM) is a congenital condition characterized by herniating cerebellar tonsils (HCTs) into the spinal canal. Although mostly managed through posterior decompression surgery, there is a lack of consensus about the need for surgery in asymptomatic patients or those with mild clinical findings. This study aimed to evaluate cerebrospinal fluid (CSF) flow parameters in patients with CM type 1 (CM-1) and compare them with posterior cranial fossa (PCF) morphometric measurements to use these measurements for predicting disease progression.

Design: Retrospective analysis.

Setting: Department of Neurosurgery, Ankara Diskapi Yildirim Beyazit Training and Research Hospital, Health Sciences University Participants: Adult patients ( n  = 95; mean age = 40.8 ± 13.8 years; 76 females) diagnosed with CM-1 between January 2017 and October 2018.

Main outcome measures: Symptoms at presentation, CSF flow score, PCF morphometric measurements-measured using brain and spinal cord magnetic resonance imaging and computed tomography.

Results: Coughing headache, presence of additional pathology (syringomyelia), PCF volume and height, Boogard's angle, foramen magnum surface area, HCT length, and HCT surface area (HCTSA) were significant factors affecting CSF flow. Further, multivariate regression analysis revealed that the HCT length and HCTSA, the presence of additional pathology, and Boogard's angle were independent predictors of CSF flow scores.

Conclusion: The morphometric measures, HCT length, HCTSA, and Boogard's angle, and the presence of additional pathology are important predictive factors for reduced CSF flow at the craniovertebral junction in patients with CM-1. These factors can help clinicians predict the disease's clinical progression and plan surgical treatment.