Surgical management of dissociated vertical deviation associated with A-pattern strabismus

IntroductionDissociated vertical deviation (DVD), pattern strabismus, and oblique muscle dysfunction frequently coexist, and the recognition of bilaterality, symmetry, and lateral incomitance is important in selecting appropriate surgical management. In this study, we compare 3 different surgical approaches in patients with DVD associated with A-pattern strabismus.MethodsThis was a retrospective review of 40 consecutive patients with DVD and A-pattern strabismus who underwent strabismus surgery. Bilateral superior rectus muscle recession was performed in 9 patients, bilateral superior rectus recession and superior oblique posterior tenectomy were performed in 14 patients, and bilateral superior oblique temporal tenotomy and inferior oblique recession were performed in 17 patients.ResultsBilateral superior rectus muscle recession corrected 7Δ ± 2Δ of A pattern, 10Δ ± 3Δ of vertical deviation and 4Δ ± 2Δ of DVD asymmetry. Bilateral superior rectus muscle recession combined with superior oblique posterior tenectomy corrected 17Δ ± 3Δ of A pattern, 10Δ ± 2Δ of vertical deviation, and 4Δ ± 2Δ of asymmetry. Bilateral superior oblique muscle temporal tenotomy combined with inferior oblique recession corrected 30Δ ± 4Δ of A pattern, 9Δ ± 3Δ of vertical deviation, and 2Δ ± 2Δ of asymmetry.ConclusionsIn patients with DVD and A patterns, the size of the A pattern and the symmetry of the DVD are of major importance for surgeons determining appropriate procedures. Bilateral superior rectus muscle recession corrects small amounts of A pattern. Larger amounts of A pattern require additional superior oblique weakening or weakening of all four oblique muscles. superior rectus muscle recession is warranted if the asymmetry is larger than 5Δ.