A Siemens Single-Shot T1 Mapping Sequence as an Alternative to MOLLI.

Abstract

Background: Native T1 mapping has become an essential tool for quantitative myocardial tissue characterization in cardiac magnetic resonance (CMR). However, widely used techniques such as Modified Look-Locker Inversion Recovery (MOLLI) remain limited by their proprietary nature and limited accessibility, particularly in resource-constrained settings.

Aim: This study aimed to develop and validate a more accessible Single-Shot T1 mapping technique as a practical alternative to MOLLI, and to assess its agreement and diagnostic performance against a reference standard (Circle Cardiovascular Imaging, CVI⁴²).

Methods: A retrospective study was conducted on 40 subjects (25 healthy controls and 15 patients with cardiac pathologies) who underwent 3T CMR imaging. Native T1 values were acquired using a modified Single-Shot inversion recovery scheme (3(3)3(3)5). Quantitative analysis was performed using custom MATLAB-based post-processing and compared with reference measurements obtained using CVI⁴² software. Agreement was assessed using Bland-Altman analysis, while group differences were evaluated using independent t-tests.

Results: Pathological subjects demonstrated significantly elevated native T1 values compared to healthy controls (1566 ± 65 ms vs. 1079 ± 80 ms, p < 0.001). The proposed method showed strong agreement with the reference standard, with a mean difference of 5.7 ms and no statistically significant bias. Additionally, the Single-Shot approach exhibited significantly reduced inter-subject variability compared to CVI⁴²-based measurements.

Conclusion: The proposed Single-Shot T1 mapping technique provides a reliable, reproducible, and accessible alternative to MOLLI, with comparable accuracy and improved numerical stability. This approach may expand access to advanced myocardial tissue characterization, particularly in low-resource settings.