Artificial Tears to Prevent Nasolacrimal Duct Obstruction in Patients Treated With Radioactive Iodine for Thyroid Cancer

October 26, 2025 updated by: Rachel Sobel, Vanderbilt University Medical Center

The Use of Artificial Tears to Prevent Nasolacrimal Duct Obstruction in Patients Who Are Treated With Radioactive Iodine for Thyroid Cancer

The association of radioiodine therapy for the treatment of thyroid cancer with nasolacrimal duct obstruction has been well documented in the medical literature. Prior case reports have documented radioactive iodine detection in the tears of patients following radioiodine therapy. It is possible that radioactive uptake by the cells in the lacrimal sac and nasolacrimal duct lead to inflammation, fibrosis, and obstruction of the tear duct over time. A recent study has shown that the administration of artificial tears decreases the level of detectable radioiodine in the tears of patients undergoing radioiodine therapy for thyroid cancer. The purpose of this study will be to assess whether administering tears after radioactive iodine therapy for thyroid cancer decreases the incidence of nasolacrimal duct obstruction in the two years following radioactive iodine treatment.

Study Overview

Status

Recruiting

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Estimated)

100

Phase

  • Phase 3

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

Yes

Description

Inclusion Criteria:

  1. Radio-iodine therapy for thyroid cancer
  2. Radioiodine therapy ≥150 mCi
  3. Age 18 or older

Exclusion Criteria:

  1. Use of eye drops, other than artificial tears
  2. History of periocular trauma with tear duct involvement/lacrimal gland trauma
  3. History of lacrimal drainage disease: canaliculitis, dacryocystitis
  4. Prior radiotherapy
  5. Current or prior use of chemotherapy drugs (i.e. 5-fluorouracil, docetaxel)
  6. Medical conditions that predispose to NLD stenosis (i.e. sarcoidosis, granulomatosis with polyangiitis, chronic lymphocytic leukemia)
  7. Nasolacrimal duct obstruction at baseline

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Prevention
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Experimental Arm (Artificial Tears)

Participants in this arm will receive artificial tears to be administered in the 4 days immediately following radioactive iodine therapy. The schedule of administration will be as follows:

Day 1 (day of radioactive iodine therapy): Every 15 minutes for 2 hours, then every 30 minutes for at least 4 hours or until bedtime at night Day 2: Once every 1 hour for 12 hours Day 3: Four times (approximately morning, lunch, dinner, and evening) Day 4: Two times (morning and evening)
Drug: Artificial Tears Methylcellulose
Participants will self-administer the artificial tears according to the schedule.
No Intervention: No Intervention (No Artificial Tears)
Participants in this arm will not administer artificial tears in the 4 days immediately following radioactive iodine therapy.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Incidence of Post-Radiotherapy Nasolacrimal Duct Obstruction (NLDO)
Time Frame: 2 years
The rate of patients that developed NLDO after radioactive iodine therapy in each experimental group as determined by tear duct irrigation by an ophthalmologist.
2 years

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Vanderbilt University Medical Center

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

August 21, 2023

Primary Completion (Estimated)

December 31, 2027

Study Completion (Estimated)

December 31, 2027

Study Registration Dates

First Submitted

August 13, 2023

First Submitted That Met QC Criteria

August 13, 2023

First Posted (Actual)

August 21, 2023

Study Record Updates

Last Update Posted (Estimated)

October 28, 2025

Last Update Submitted That Met QC Criteria

October 26, 2025

Last Verified

October 1, 2025

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 230845

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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