Free-breathing pediatric cardiac dark-blood imaging with reverse double inversion-recovery and single-shot deep learning reconstruction.

BACKGROUND

Dark-blood T2-weighted fast spin-echo (DB-FSE) is sensitive to motion, leading to signal dropout artifacts and ghosting artifacts in free-breathing pediatric cardiac imaging, which severely impairs its diagnostic quality. Here, we aimed to fulfill high-resolution motion-robust edema assessment during free-breathing by combining reverse double inversion recovery (RDIR) and single-shot DB-FSE based on artificial intelligence (AI)-assisted compressed sensing (ACS) reconstruction.

METHODS

This prospective study included 20 healthy children and 47 pediatric patients. Three imaging techniques were compared: routine multi-shot DB-FSE based on double inversion recovery (MS-DIR), multi-shot DB-FSE based on RDIR (MS-RDIR), and single-shot DB-FSE based on RDIR (SS-RDIR) with ACS reconstruction. These methods were compared via quantitative metrics, including total acquisition time, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR), and qualitative metrics, including myocardial visibility, ghosting artifacts, and overall quality.

RESULTS

In healthy children, the total acquisition time (seconds) of SS-RDIR (64.8±21.8) was significantly less than those of MS-DIR (222.5±69.3, P<0.001) and MS-RDIR (234.0±64.1, P<0.001). The SNR and CNR were comparable (P=0.094 for SNR and P=0.054 for CNR). Ghosting artifacts were significantly reduced in SS-RDIR (4.70±0.18) compared to MS-DIR (3.95±0.28, P<0.001) and MS-RDIR (3.97±0.31, P<0.001), whereas overall quality was improved in SS-RDIR (4.42±0.19) compared to MS-DIR (3.87±0.27, P=0.004) and MS-RDIR (3.95±0.34, P=0.010). In patients, SS-RDIR significantly reduced the total acquisition time compared to MS-DIR (62.1±24.0 216.6±74.2, P<0.001) and MS-RDIR (229.8±79.2, P<0.001), with comparable SNR (P=0.065) and CNR (P=0.089). SS-RDIR also showed less severe ghosting artifacts (4.94±0.11) compared to MS-DIR (3.77±0.29, P<0.001) and MS-RDIR (3.78±0.34, P<0.001), and better quality (3.96±0.52) than MS-DIR (3.61±0.40, P=0.023).

CONCLUSIONS

SS-RDIR with ACS reconstruction offers substantially shorter scan time and superior image quality than traditional multi-shot techniques. This approach enhances clinical workflow and patient comfort, facilitating a broader application of DB-FSE in pediatric cardiac imaging.