Case report: unilateral mydriasis following nasal cautery.

We report a case of unilateral mydriasis following nasal electrocautery presumed to be the result of retrograde flow of adrenaline and/or xylometazoline hydrochloride (Otrivine) through the nasolacrimal duct into the eye. We review the literature and highlight the importance of correct interpretation of finding a dilated pupil post-operatively. To our knowledge. we report the first such case involving xylometazoline hydrochloride and also following nasal electrocautery. Unilateral mydriasis is alarming after nasal surgery but must be interpreted with caution. During minimally invasive procedures it is likely to be due to the effects of topical medication to the nose rather than surgical trauma.