Investigative Radiology

Krittayaphong, Rungroj; Saiviroonporn, Pairash; Zhang, Shuo; Viprakasit, Vip; Tanapibunpon, Prajak; Yindeengam, Ahthit; Komoltri, Chulaluk

doi: 10.1097/rli.0000000000001261pmid: 41261381

Objectives: Accurate detection and quantification of liver iron overload (LIO) in patients with thalassemia is crucial for guiding iron chelation therapy and preventing iron-related organ damage. While conventional multiecho gradient-echo (GRE) based MR at 1.5T is the clinical standard, with increasing availability of 3.0T systems, clinically reliable alternatives are needed. The ultra-short echo time (UTE) MRI sequence may offer improved assessment of LIO on 3.0T. The objective of this study was to evaluate 3.0T UTE for assessing LIO in thalassemia patients and directly compared with the standard 1.5T GRE as reference, particularly at severe overload with lower R2* values. Materials and Methods: Patients with thalassemia referred for liver iron assessment by MRI were prospectively enrolled. Each participant underwent liver iron quantification using both 1.5T GRE and 3.0T UTE sequences. For the latter, 4 different acquisition protocols were assessed: 7-echo free breathing (3.0T UTE 7E FB), 7-echo breath-hold (3.0T UTE 7E BH), 15-echo free breathing (3.0T UTE 15E FB), and 15-echo breath-hold (3.0T UTE 15E BH). The correlation between 1.5T GRE and each UTE sequence was analyzed. The agreement was further assessed using Bland-Altman analysis. Results: Sixty-three patients were enrolled; 5 were excluded due to unmeasurably high liver iron concentration (LIC) by 1.5T MRI. The remaining 58 patients had a mean age of 34.3 ± 16.1 years; 24 (41.4%) were male, and 42 (72.4%) had thalassemia major. Regular transfusions were noted in 31 (53.4%). All 3.0T UTE sequences demonstrated excellent correlation with 1.5T GRE (R 2, 0.9701-0.9827). Bland-Altman analysis indicated minimal bias and narrow limits of agreement. The 3.0T UTE 15E BH protocol yielded the strongest performance. Conclusions: 3.0T UTE MRI sequences provide clinically feasible and accurate assessment of liver iron overload in thalassemia patients across a broad range of LIC values from 1.3 to 39.5 mg/g. These findings support the clinical utility of 3.0T UTE MRI for LIO detection and therapeutic decision-making in this population.