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

Abstract

To assess the use of functional scores in the evaluation of patients with dural arteriovenous fistula and Foix-Alajouanine syndrome. 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. The quantitative synthesis included 18 patients. Surgery alone was performed in 11 patients (61.11%); 7patientsunderwent 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. 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.