Clinical Features of Surgery Candidates for Different Types of Extraocular Muscle Palsy

Introduction: Clinical manifestations of cranial nerve palsies are of great importance, and surgeons should consider them before planning surgical protocol. Materials and Methods: This retrospective study was conducted on preoperative hospital records of 598 Iranian patients with different types of extraocular muscle palsy, including third (90 patients), fourth (501 patients), and fifth (7 patients) nerve palsy at Farabi Hospital, Tehran Province, Iran. Results: In terms of fourth nerve palsy, the mean spherical equivalent (SE) in the right and left eye was 0.23±1.51 and 0.19±1.45 diopter, respectively. Also, the mean angle of vertical deviation was 15.54±8.85 Δ at near and 15.66±8.93 Δ at far. In patients with third nerve palsy, the mean SE in the right and left eye was -0.02±2.08 and 0.08±1.95 diopter, respectively. Also, the mean angle of vertical deviation was 17.8±17.4 Δ at near and 17.8±17.5 Δ at far. In terms of six nerve palsy, the mean SE in the right and left eye was -1.27±3.37 and -1.08±2.52 diopter, respectively. Also, the mean angle of esotropia was 32.4±7.7 Δ at near and 33±6.7 Δ at far. The frequency of amblyopia in patients with third, fourth, and sixth nerve palsies was 21 patients (23.3%), 70(14%), and 4(57.1%), respectively. Conclusion: The clinical characteristics of patients with different types of EOM palsy are remarkably different, which can be attributed to the different properties of these kinds of deviations.