Incomitant Exotropia After Nasal Polyp Surgery.

Area of Science:

• Ophthalmology
• Neurosurgery

Background:

• Incomitant exotropia is a known ocular complication following intranasal surgery.
• This report details the etiology of exotropia in a patient post-nasal polyp surgery.

Observation:

• A 50-year-old male presented with diplopia and right eye outward deviation one month after nasal polyp surgery.
• Examination revealed significant exotropia (XT 45° Hirschberg, >95 ∆BI Krimsky) and limited right eye adduction.
• Head MRI showed right medial recti atrophy (2.2 mm) without rupture.

Findings:

• The patient underwent vertical muscle transposition surgery due to medial recti atrophy.
• Post-operatively, diplopia decreased, and exotropia improved (XT 30° Hirschberg, 65°∆BI Krimsky).

Implications:

• Unlike typical cases, this exotropia was not caused by extraocular muscle rupture.
• Abnormalities in muscle vascularization, evidenced by medial recti atrophy, are suspected causes.
• This suggests a need to consider vascular factors in managing post-intranasal surgery incomitant exotropia.