Moving Beyond Morphometrics and Alignment: Prospective Longitudinal Study on Cognition, Quality of Life, and...

Chiari type I malformation (CMI) has been implicated to cause cognitive impairment. Unusual for a craniovertebral junction (CVJ) anomaly, this phenomenon is postulated to be related to microstructural changes across the brain. However, this has not been confirmed in a longitudinal study, in bony CVJ anomalies, or in the context of quality of life (QOL). This study aimed to analyze cognition, QOL, and diffusion tensor imaging (DTI) metrics before and after surgery for congenital CVJ anomalies and evaluate their correlations with conventional clinico-radiological factors.

Fifty-seven patients with congenital CVJ anomalies-CMI, atlantoaxial dislocation (AAD), and basilar invagination (BI)-were evaluated in this prospective longitudinal study over 3 years with a neuropsychological battery, QOL and functional scores, and DTI metrics. A total of 43 patients (23 with CMI; 20 with AAD or BI) with 1-year postsurgical data were included in the final analysis.

Cognitive dysfunction in one or more domains was noted in 15 (65%) of the patients with CMI and 16 (80%) of the patients with AAD/BI. Memory and visual motor perception were the most-affected domains in both the cohorts. At the 1-year follow-up, the proportion of patients demonstrating an overall cognitive dysfunction did not change significantly ( P > .05). All patients demonstrated significant postoperative improvement in functional and QOL scores at follow-up. DTI metrics improved in many regions postoperatively, but did not correlate with functional or cognitive changes ( P > .05).

Cognition is affected in a majority of patients with CMI, AAD, or BI. These patients experience good functional and QOL outcomes after surgery but most of them continue to exhibit cognitive impairment. DTI metrics improve after surgery, but do not correlate with cognitive changes. These findings underline the multidimensional nature of the pathology of these anomalies that complicate achieving the concept of a "successful" surgery.