Radioactive Iodine Treatment for Thyroid Cancer Complicated by Lacrimal Sac Retention of Iodine

Patients with intermediate-risk thyroid cancers may undergo treatment with radioactive iodine-131 (I-131). They often undergo a pretreatment diagnostic iodine scan that typically shows areas of physiological uptake in the stomach, bladder, parotid glands as well as thyroid-remnant uptake and sites of metastatic disease. A 48-year-old woman with intermediate-risk papillary thyroid cancer with metastases to lateral compartment lymph nodes was found to have increased retention of iodine in the medial portion of her left orbit on the diagnostic scan. This was suggestive of preexisting nasolacrimal duct stenosis leading to retention of secretions in the lacrimal sac, raising concerns that the I-131 used in treatment would have delayed clearance that could further damage her lacrimal sac and eye. In consultation with ophthalmology, the patient received pretreatment azelastine and prednisolone drops and underwent treatment with radioactive iodine followed by saline lacrimal irrigation. Though she had subsequent eye pain and swelling necessitating repeated irrigation, the patient was able to undergo treatment for her papillary thyroid cancer and retained full function of her eye. This case highlights an approach that could be used for patients with nasolacrimal duct stenosis in whom radioactive iodine treatment is deemed beneficial.