Dixon-T2WI magnetic resonance imaging at 3 tesla outperforms conventional imaging for thyroid eye disease.

OBJECTIVES: To determine the diagnostic performances of a single Dixon-T2-weighted imaging (WI) sequence compared to a conventional protocol including T1-, T2-, and fat-suppressed T2-weighted MRI at 3 T when assessing thyroid eye disease (TED). MATERIALS AND METHODS: This IRB-approved prospective single-center study enrolled participants presenting with confirmed TED from April 2015 to October 2019. They underwent an MRI, including a conventional protocol and a Dixon-T2WI sequence. Two neuroradiologists, blinded to all data, read both datasets independently and randomly. They assessed the presence of extraocular muscle (EOM) inflammation, enlargement, fatty degeneration, or fibrosis as well as the presence of artifacts. The Wilcoxon signed-rank test was used. RESULTS: Two hundred six participants were enrolled (135/206 [66%] women, 71/206 [34%] men, age 52.3 ± 13.2 years). Dixon-T2WI was significantly more likely to detect at least one inflamed EOM as compared to the conventional set (248/412 [60%] versus 228/412 [55%] eyes; (p = 0.02). Dixon-T2WI was more sensitive and specific than the conventional set for assessing muscular inflammation (100% versus 94.7% and 71.2% versus 68.5%, respectively). Dixon-T2WI was significantly less likely to show major or minor artifacts as compared to fat-suppressed T2WI (20/412 [5%] versus 109/412 [27%] eyes, p < 0.001, and 175/412 [42%] versus 257/412 [62%] eyes, p < 0.001). Confidence was significantly higher with Dixon-T2WI than with the conventional set (2.35 versus 2.24, p = 0.003). CONCLUSION: Dixon-T2WI showed higher sensitivity and specificity and showed fewer artifacts than a conventional protocol when assessing thyroid eye disease, in addition to higher self-reported confidence. KEY POINTS: • Dixon-T2WI has better sensitivity and specificity than a conventional protocol for assessing inflamed extraocular muscles in patients with thyroid eye disease. • Dixon-T2WI shows significantly fewer artifacts than fat-suppressed T2WI. • Dixon-T2WI is faster and is associated with significantly higher self-reported reader confidence as compared to a conventional protocol when assessing inflammatory extraocular muscles.

Efficacy of rituximab in patients with Graves' orbitopathy: a retrospective multicenter nationwide study.

PURPOSE: The clinical utility of rituximab (RTX) in Graves' orbitopathy (GO) treatment remains controversial since the discrepant results from 2 prospective randomized studies (Stan M et al. J Clin Endocrinol Metab 2015; Salvi M et al. J Clin Endocrinol Metab 2015). The aim of this study was to assess in real life the characteristics and the clinical outcomes of patients with GO treated with RTX in cases of corticosteroid resistance or corticosteroid dependence. METHODS: Multicenter French retrospective study including patients with moderate-to-severe GO requiring second-line treatment with RTX. Patients were classified according to three main baseline characteristics: clinical inflammation (CAS ≥ 3), oculomotor limitation, and visual dysfunction. Patients were considered as responders if, at 24 weeks (week 24), at least 1 of these 3 parameters improved with no worsening elsewhere. RESULTS: Forty patients were included (65% smokers, 38% dysthyroidism). Thirty-two patients were treated with RTX alone (one patient excluded owing to side effects): 64.5% had favorable responses at week 24 and significant reduction in baseline CAS (3.29 ± 1.6) at 12 weeks (1.93 ± 1.1; P < 0.001) and at week 24 (1.59 ± 1.1; P < 0.001); reduction in anti-TSH receptor antibodies at week 24 (P < 0.01); and significant improvement of visual acuity (P = 0.04) and ocular hypertonia (P = 0.04) at week 12, but no improvement in oculomotor dysfunction. Eight patients needed emergency treatment with concomitant RTX and orbital decompression, with favorable outcome for 5 patients. Predictive factors for a poor response to RTX were low baseline CAS, smoker, and baseline ocular hypertonia. All patients reported good tolerance except one serious side effect (a cytokine release syndrome). CONCLUSIONS: The efficiency results of RTX in reducing CAS in this cohort are just between those of Stan and Salvi. This could be explained by our delay before treatment initiation, quicker than Stan but longer than Salvi. RTX appears to be effective as a second-line treatment for the inflammatory component of GO, especially if the disease is highly active and recent.