To report visual acuity outcomes and potential complications in patients undergoing endoscopic transnasal orbital decompression in the setting of acutely deteriorating sight secondary to dysthyroid optic neuropathy (DON) unresponsive to corticosteroid therapy. No previous reports describe vision outcomes in this specific patient population undergoing urgent endoscopic decompression.

Retrospective case review at a tertiary-care academic hospital. Four patients with DON were identified that underwent urgent endoscopic orbital decompression for acutely deteriorating vision. Three patients underwent a later decompression of the other orbit, yielding seven decompressions in total for acutely deteriorating vision. Operative technique entailed inferior and medial wall decompressions. The posterior limit of medial wall decompression was within the sphenoid, just anterior to the annulus of Zinn to fully decompress the optic nerve. Primary outcome was visual acuity.

In all seven decompressions, visual acuity improved substantially. In 5/7 eyes, preoperative vision was severely impaired at 20/150 or worse. Two eyes had mild and moderate impairment at 20/50 and 20/100. Post-operatively, the moderately and severely impaired eyes improved to 20/60 or better. No complications were encountered.

Transnasal endoscopic orbital decompression is a safe, effective treatment for acutely worsening visual loss from DON. All cases demonstrated significant objective improvement in visual acuity. Given the need for later contralateral decompression in 3 patients, consideration should be given to performing bilateral orbital decompressions at the time of surgery.