Obstrução de vias lacrimais associada ao tratamento radioiodoterápico de carcinoma de tireoide

Abstract

Purpose: To report the finding of nasolacrimal drainage system obstruction associated with radio iodine therapy and to review clinical data and the surgical treatment outcome of this rare complication. Methods: We retrospectively analyzed ophthalmological data of patients with history of thyroid carcinoma that underwent radioactive iodine I-131 therapy and were referred to lacrimal surgery. Results: 17 patients with thyroid cancer treated with thyroidectomy and radioactive iodine I-131 therapy presented symptomatic nasolacrimal duct obstruction after 13.2 months following cancer treatment. 11 patients presented bilateral epiphora, 8 had lacrimal sac mucocele. Age range was 30 to 80 years, 10 patients had less than or equal to 49 years. The mean cumulative dose of radioiodine was 571mCi (range: 200-1200 mCi). Nasal obstruction symptoms and increased salivary glands were also present in 53% of patients. All subjects underwent dacryocystorhinostomy. Dilation of the lacrimal sac and increased intraoperative bleeding was also observed in 3 younger patients. Complete epiphora and dacryocystitis resolution after surgery occurred in 82.4%, and partial in 17.6% (3 patients that still presented unilateral relapse after correction of bilateral obstruction). Mean follow-up was 6 months (range: 2-24 months). Conclusions: Cumulative high dose of radioidine, nasal and salivary gland dysfunction are associated with lacrimal drainage obstruction. We observed a great percentage of younger patients presenting dacryocystitis when compared to the idiopathic dacryostenosis. Radioactive iodine uptake by nasolacrimal duct mucosa with subsequent inflammation, edema and fibrosis seems to have a relationship tolacrimal duct obstruction. The knowledge of this complication is important for the study and proper management of these patients.