PT - JOURNAL ARTICLE AU - Michael Oeverhaus AU - Jana Koenen AU - Nikolaos Bechrakis AU - Mareile Stöhr AU - Ken Herrmann AU - Wolfgang Peter Fendler AU - Anja Eckstein AU - Manuel Weber TI - Radioiodine ablation of thyroid remnants in patients with Graves’ orbitopathy AID - 10.2967/jnumed.122.264660 DP - 2022 Nov 01 TA - Journal of Nuclear Medicine PG - jnumed.122.264660 4099 - http://jnm.snmjournals.org/content/early/2022/11/23/jnumed.122.264660.short 4100 - http://jnm.snmjournals.org/content/early/2022/11/23/jnumed.122.264660.full AB - Purpose: To assess response following ablation of thyroid remnants (ATR) with radioactive iodine therapy (RAIT) in patients with unstable Graves’ orbitopathy (GO) after (subtotal) thyroidectomy. Methods: 30 patients with mild (n = 4, 13%), moderate-to-severe (n = 25, 83%) and very severe GO (n = 1, 3%) were analyzed in this retrospective study. Primary endpoint was the improvement of GO-related symptoms as assessed by CAS, NOSPECS, and soft-tissue inflammation score 3 and 12 months after ATR. Ablation success was defined by a decrease in 99mTechnetium-uptake (TcTU) on thyroid scintigraphy, remnant volume, and TSH-receptor antibody levels (TRAb) 3 months after ATR. Results: Twelve months after ATR CAS, NOSPECS, and soft-tissue inflammation scores showed a significant decrease from 2.8 to 1.3 (P = <0.0001), 5.9 to 4.9 (P = 0.007), and 4.7 to 2.1 (P = 0.0001), respectively. After 3 months 27/30 (90 %) patients had inactive GO and 29/30 (97 %) after 12 months. No new activation of GO occurred. Remnant volume (1.4 vs. 0.4ml, P = <0.0001), mean TRAb titer (19.02 IU/l vs. 13.37 IU/l, P = <0.0001), and TcTU (0.5% vs. 0.1%; n = 12; P = 0.04) decreased significantly until 3 months after ATR. Discussion: RAIT after Thyroidectomy can successfully ablate residual thyroid remnants leading to an improvement of GO, reduction of inflammatory activity and stabilization of thyroid function.