Dural Arteriovenous Fistula and Foix-Alajouanine Syndrome: Assessment of Functional Scores with Review of Pathogenesis.

OBJECTIVE: To assess the use of functional scores in the evaluation of patients with dural arteriovenous fistula and Foix-Alajouanine syndrome.

METHODS: We systematically surveyed the literature to identify relevant patients. Aminoff-Logue Scale (ALS) and modified Rankin Scale (mRS) scores were ascertained and combined to form a novel functional score, the Aminoff-Rankin Composite (ARC) score. We compared functional scores between surgery and embolization groups and ran one-sided point-biserial analyses to test our expectation that positive correlations exist between functional scores and treatment outcomes. Finally, we reviewed the pathogenesis of dural arteriovenous fistula formation.

RESULTS: The quantitative synthesis included 18 patients. Surgery alone was performed in 11 patients (61.11%); 7 patients underwent embolization alone (38.89%). There were no significant differences in functional scores or symptom outcomes when we compared surgery to embolization. The pre-intervention ALS gait, mRS, and ARC scores were correlated with improved symptoms (rpb = 0.43, P = 0.04; rpb = 0.47, P = 0.02; rpb = 0.48, P = 0.04, respectively). In patients whose symptoms were improved, post-intervention ALS gait and micturition scores (2.55 vs. 4.43, P = 0.02 and 1.09 vs. 2.71, P = 0.01, respectively) and post-intervention ARC scores (6.66 vs. 11.57, P = 0.01) were on average lower than in patients whose symptoms were unimproved.

CONCLUSIONS: We believe that patients with dAVF and Foix-Alajouanine syndrome present with worse function (higher functional scores) as a result of an acute myelopathic episode, and that if diagnosed and treated appropriately, will experience some level of symptom improvement that is evidenced by reduced post-intervention functional scores.