To evaluate the outcomes of endonasal or external dacryocystorhinostomy in patients who underwent radioiodine therapy due to thyroid cancer.

We reviewed retrospectively clinical and microbiological records of patients who had endonasal or external dacryocystorhinostomy after taking radioiodine therapy for thyroid cancer between January 2006 and December 2012.

Twenty-three female adult patients with an average age of 50 years (range, 25 to 72 years) were identified. Seven patients underwent unilateral surgery and 16 had bilateral surgery. Among 39 eyes, 1 eye had combined nasal septoplasty, 3 eyes had external dacryocystorhinostomy and 36 eyes had endonasal dacryocystorhinostomy. Dacryocystorhinostomy was performed within 12 months after the last ¹³¹I dose in 3 cases and 2 (5%) presented with the symptom of epiphora. The major cause of symptomatic recurrence was restenosis of the lacrimal nasal mucosa due to the formation of scar tissue, thus, the patients underwent revision surgeries. The remaining 37 of the 39 eyes (95%) showed improvement of symptoms.

Most patients who underwent dacryocystorhinostomy after ¹³¹I therapy due to thyroid cancer showed successful outcomes, especially after more than 1 year post-operatively. The major cause of nasolacrimal duct obstruction was a scar tissue formation in the nasal cavity mucosa.