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Nasolacrimal Duct Obstruction on 131I SPECT/CT: Atypical False-positive Paranasal Radioiodine Uptake as a Complication of Single-dose RAI Treatment


  • Nuh Filizoğlu
  • Kevser Öksüzoğlu
  • Salih Özgüven
  • Onur Buğdaycı
  • Tanju Yusuf Erdil

Received Date: 10.03.2021 Accepted Date: 08.07.2021 Mol Imaging Radionucl Ther 2022;31(3):234-236 PMID: 36268911

Nasolacrimal duct obstruction (NLDO) is a rare complication after radioiodine therapy and may cause false positive 131I uptake at the point of obstruction in 131I whole body scan. Here, we report a 59-year-old female patient with papillary thyroid cancer treated with total thyroidectomy followed by 131I therapy. 131I whole body scan revealed focal uptake in the head. Single photon emission computed tomography/computed tomography (CT) showed focal uptake at the right proximal nasolacrimal duct. The ophthalmologic examination and the diagnostic maxillofacial CT confirmed the diagnosis of NLDO.

Keywords: 131I, radioiodine therapy, nasolacrimal duct obstruction, thyroid cancer


Informed Consent: Informed consent form was obtained.

Peer-review: Externally peer-reviewed.

Authorship Contributions

Surgical and Medical Practices: N.F., K.Ö., S.Ö., O.B., T.Y.E., Concept: N.F., T.Y.E., Design: N.F., T.Y.E., Data Collection or Processing: N.F., K.Ö., Analysis or Interpretation: N.F., T.Y.E., Literature Search: N.F., T.Y.E., Writing: N.F., S.Ö.

Conflict of Interest: No conflict of interest was declared by the authors.

Financial Disclosure: The authors declared that this study received no financial support.


  1. Ali MJ. Iodine-131 Therapy and nasolacrimal duct obstructions: what we know and what we need to know. Ophthalmic Plast Reconstr Surg 2016;32:243-248.
  2. Burns JA, Morgenstern KE, Cahill KV, Foster JA, Jhiang SM, Kloos RT. Nasolacrimal obstruction secondary to I(131) therapy. Ophthalmic Plast Reconstr Surg 2004;20:126-129.
  3. Fard-Esfahani A, Mirshekarpour H, Fallahi B, Eftekhari M, Saghari M, Beiki D, Ansari-Gilani K, Takavar A. The effect of high-dose radioiodine treatment on lacrimal gland function in patients with differentiated thyroid carcinoma. Clin Nucl Med 2007;32:696-699.
  4. Morgenstern KE, Vadysirisack DD, Zhang Z, Cahill KV, Foster JA, Burns JA, Kloos RT, Jhiang SM. Expression of sodium iodide symporter in the lacrimal drainage system: implication for the mechanism underlying nasolacrimal duct obstruction in I(131)-treated patients. Ophthalmic Plast Reconstr Surg 2005;21:337-344.
  5. Yuoness S, Rachinsky I, Driedger AA, Belhocine TZ. Differentiated thyroid cancer with epiphora: detection of nasolacrimal duct obstruction on I-131 SPECT/CT. Clin Nucl Med 2011;36:1149-1152.
  6. Fard-Esfahani A, Farzanefar S, Fallahi B, Beiki D, Saghari M, Emami-Ardekani A, Majdi M, Eftekhari M. Nasolacrimal duct obstruction as a complication of iodine-131 therapy in patients with thyroid cancer. Nucl Med Commun 2012;33:1077-1080.
  7. Brockmann H, Wilhelm K, Joe A, Palmedo H, Biersack HJ. Nasolacrimal drainage obstruction after radioiodine therapy: case report and a review of the literature. Clin Nucl Med 2005;30:543-545.
  8. Ali MJ, Vyakaranam AR, Rao JE, Prasad G, Reddy PV. Iodine-131 therapy and lacrimal drainage system toxicity: nasal localization studies using whole body nuclear scintigraphy and SPECT-CT. Ophthalmic Plast Reconstr Surg 2017;33:13-16.