Unilateral or Bilateral Superior Oblique Muscle Palsy in Ocular Torticollis? A case report

Purpose: To report a case of ocular torticollis successfully treated by bilateral inferior oblique weakening surgery. Methods: Interventional case report. Results: A 4-year-old boy presented to our clinic with left head tilt over a prolonged period. He had received rehabilitation for torticollis for 1 year; however,the head tilt persisted. Cycloplegic refraction was +0.50D in both eyes without astigmatism. Bare visual acuity was 25/25 in both eyes. Right hypertropia was observed in the primary position. Ocular examination demonstrated right superior oblique palsy and right inferior oblique overactivity. Large right hypertropia (15 prism diopters) was observed on right head tilt testing. Further, slight V-pattern strabismus and bilateral fundus extorsion were found. Asymmetric bilateral superior oblique palsy with secondary inferior oblique overaction was initially diagnosed. The patient subsequently underwent right eye inferior oblique myectomy and left eye inferior oblique marginal myotomy. The preoperative abnormal head position was greatly improved following surgical intervention. However, left superior oblique muscle palsy with left inferior oblique muscle overactivity progressively worsened 6 months after surgery. Conclusion: Ocular torticollis is defined as an eye-related condition leading to abnormal head posture. The commonest causes of ocular torticollis are superior oblique palsies, either unilateral or bilateral. Bilateral superior oblique palsies can be so asymmetric that the lesser affected eye is almost masked preoperatively. Accurate diagnosis is dependent on careful physical examination, such as the head tilt test and ocular examination, and evaluation for signs of ＂V patten＂ strabismus or fundus extorsion. With accurate diagnosis, ocular torticollis can be curatively treated with extraocular muscle surgery.