Long Term Outcome of Surgery for Vertical Strabismus Secondary to 4th Nerve Palsy
Alina V. Dumitrescu; Scott A. Larson; Arlene V. Drack; Richard J. Olson; Pavlina S. Kemp; William E. Scott
University of Iowa
Iowa City, IA
Introduction: Patients with vertical strabismus due to 4th nerve palsy require surgical correction for diplopia and abnormal head postures. This study evaluates our long term outcome in surgical treatment of this condition.
Methods: Retrospective chart review 1995 – 2015. Patients with surgically treated 4th nerve palsy and at least 5 years of follow up were included. Criteria for surgical success: elimination of abnormal head position if present preoperatively, elimination of diplopia and fusion of the Worth 4-dot +/- using a small amount of prism (< 5 PD).
Results: 68 charts meet the inclusion criteria.
• 32/68 (62%) meet the success criteria
• 26/68 (38%) unsatisfactory results and require a reoperation during the follow up period
• 15/26 (58%) undercorrections (residual vertical deviation, late recurrent vertical deviation and/or residual torsion)
• 8/26 (31%) masked bilateral SOP
• 3/26 (12%) overcorrections
• 8/26 (31%) were performed within 12 months after the surgery due to immediate unsatisfactory result – 6/8 of masked bilateral cases and 2/15 undercorrections
• 18/26 (69%) experienced late overcorrections (3/18) or recurrence (13/18) and underwent additional surgery 2 to 10 years later. 2/8 cases of masked bilateral had small deviation immediate postop that worsen over time
• 3rd surgery – 4 patients, for residual vertical strabismus and torsion (all bilateral cases)
• 4th surgery – 2 patients, same reasons
Discussion: Long term follow up reveals the late overcorrections and recurrent cases
Conclusion: • Good results immediate postoperative did not correlate with long term result in 17/64 (26.5%) of the patients
• 62% of the patients had a long term satisfactory outcome after one surgery.
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2. Scott WE, Kraft SP. Classification and surgical treatment of superior oblique palsies: I. Unilateral superior oblique palsies. Trans New Orleans Acad Ophthalmol. 1986;34:15–38. [PubMed]
3. von Noorden GK, Murray E, Wong SY. Superior oblique paralysis. A review of 270 cases. Arch Ophthalmol. 1986 Dec;104(12):1771–1776. [PubMed]