The Role of Radioactive Iodine in Thyrotoxicosis Patients

Aims: The primary objective of this study is to investigate the treatment of Graves' Disease (GD) with radioactive iodine (131I-NaI), presenting the clinical symptoms suffered from patients, and evaluating the level of triiodothyronine (T3), thyroxine (T4) and thyroid-stimulating hormone (TSH) before and after the therapy procedure.
Study Design: This project is considered as a retrospective project, non-randomized, observational clinical case series. Clinical symptoms produced by GD were stratified according to patients’ gender and age, and a comparison between T3, T4 and TSH was done before and after the radioiodine therapy.
Place and Duration of Study: This study was conducted under supervision of the Department of Nuclear Medicine, King Abdulaziz University Hospital (KAUH) and the Department of Diagnostic Radiology (KAU), Jeddah, KSA, from November 2012 to May 2013.
Methodology: The records of patients with clinical diagnosis of Thyrotoxicosis who were registered in the nuclear medicine department during academic year 2012-2013 to perform thyroid scan retrospectively were analyzed. Data from 21 patients was collected before and after the administration of radioiodine therapeutic activity. Thyroid scintigraphy and thyroid functional tests (TFT) were conducted on all patients enrolled in the present study.
Results: The most common clinical symptoms produced by GD were tachycardia, weight loss, excessive sweating and tremors. A total of 90% of the patients were under anti-thyroid drug medication before taking radioiodine therapy while 10% were not. TFT results showed that 95% of patients presented abnormal thyroid function. Aside from excessive sweating, no significant association between age and clinical symptoms was observed. A significant increase in TSH level and decrease in T3 and T4 was observed at three-months after therapy procedure. Within six months post-therapy, 60% of patients showed clinical symptoms of hypothyroidism, 30% presented TFT results compatible with normal thyroid function, and only 10% showed no response to treatment.
Conclusion: Radioactive iodine is an excellent alternative for GD treatment compared to other therapeutic approaches, presenting less complication than surgery procedure and reverse possibility when patients are treated with anti-thyroid drug medication.