A Case of Medial Rectus Muscle Injury after Functional Endoscopic Sinus Polypectomy and Ethmoidectomy

ABSTRACT

PURPOSE: To report appropriate treatment of medial rectus muscle injury after functional endoscopic sinus polypectomy and ethmoidectomy METHODS: The author experienced the right medial rectus muscle injury after functional endoscopic polypectomy and ethmoidectomy in a 42-year-old man who complained of decreased visual acuity, ocular pain, binocular diplopia, and exophthalmos in the right eye at the first postoperative day. His best corrected visual acuity of right eye was 0.3, Intraocular pressure was 26 mmHg, and pupillary light reflex was decreased. On exophthalmometry, the right eye was more exophthalmic by 3 mm than the left eye. After steroid therapy and befunolol eyedrops instillation, the visual acuity was improved to 0.8 and intraocular pressure was decreased to 18 mmHg. There was severe limitation of medial gaze and about 65 prism diopters of right exodeviation in red filter test. In computerized tomography, bony defect in the right orbital medial wall and defect in the right medial rectus muscle were confirmed. On the third postoperative day, silastic sheet was applied in dehiscent medial wall under endoscopic examination in otorhinolaryngologic outpatient department. Because exodeviation and diplopia had not improved, on the 61th postoperative day, right lateral rectus muscle recession 12 mm was carried out, and then, on the 88th postoperative day, Hummelsheim operation on right eye was done. RESULTS: Right exodeviation was decreased by about 40 prism diopters after right lateral rectus muscle recession 12 mm. and then, after Hummelsheim operation, he had right exodeviation 20 prism diopters of and less binocular diplopia. We prescribed 10 prism diopters of prism lens in each eye, but he complained of decreased visual acuity and cosmetic problem. So, we prescribed 5 prism diopters of prism lens in each eye. At the last follow-up he is satisfied with his visual acuity and cosmetic aspect.