Superior Oblique Muscle Palsy: Clinical Characteristics and Surgical Approach in 1057 Patients
Babak Masoomian1 *, Mohammad Reza Akbari2 , Mottahareh Sadeghi2 , Arash Mirmohammadsadeghi2
- Frabi Eye Hospital. Tehran University of medical sciences
- Farabi eye hospital. Tehran university of medical sciences
Abstract: To evaluate the clinical findings of patients with superior oblique muscle palsy (SOP) who had surgery.
Methods: This historical cohort study was performed on 1057 SOP patients managed with surgery in Farabi Eye Hospital from January 2011 to February 2021. We collected data from the medical documents, including best-corrected distance visual acuity (CDVA), refraction, laterality, angle of deviation in different gazes, abnormal head posture (AHP), and the number and type of surgeries.
Results: The mean age of patients was 21.7 ± 14.8 (range, 1-82) years [557 males (52.7%) and 500 females (47.3%)]. Unilateral SOP was found in 990 (91.8%) patients with a mean age of 21.8 ± 14.8 (range 2 to 84) years. Unilateral SOP was congenital in 715 (72.2%) and acquired in 275 (27.8%) cases (P<.001) [471 (47.6%) right eye and 519 (52.4%) left eye (P=0.127)]. Bilateral SOP was detected in 67 (6.3%) patients with a mean age of 19.4 ± 15.6 (range 1-73) years which 18 (27%) cases had masked type. The mean angle of vertical deviation in primary position at far in unilateral and bilateral patients was 15.6± 8.2 and 14.3 ± 9.1, respectively (P<.001). In unilateral cases, AHP was detected in 847 (85.5%) patients and 12 (1.2%) had paradoxical head posture. Amblyopia was found in 89(9.9%) unilateral and 7(10.3%) bilateral cases. Solitary inferior oblique myectomy, was the most common surgery in both unilateral (n=756, 77.1%) and bilateral (n=35, 52.2%) patients. The second surgery was performed for 84 (8.6%) unilateral and 33(49.3%) bilateral cases (P<0.001). The CDVA difference between eyes, the prevalence of amblyopia, and the mean angle of horizontal deviation at near and far in patients needing two or more-times surgery was significantly higher than in cases managed with one surgery (all P<0.05).
Conclusion: Congenital SOP was two and half times as frequent as acquired SOP. About 90% of unilateral and 50% of bilateral patients managed with one surgery. Amblyopia and significant horizontal deviation were the most important factors for reoperation.
