Superior dorsal nigral hyperintensity depiction at 7 T MRI using CLEAR-DESS improves diagnosis performance of Parkinson’s disease

This study aimed to compare the qualitative and quantitative measurement of dorsal nigral hyperintensity (DNH) and its diagnostic efficacy for Parkinson’s disease (PD) between 7 T MRI sequences: the combined liquid and blood vessel attenuation with refined double echo steady state (CLEAR-DESS) and susceptibility-weighted imaging (SWI). Following sequence simulation and optimization, a prospective study enrolled 33 PD patients and 52 healthy controls, all undergoing 7 T MRI with CLEAR-DESS and SWI. Four blinded observers qualitatively assessed image quality and DNH visibility, while two independent readers performed quantitative analyses of signal-to-noise (SNR) and contrast-to-noise ratios (CNR). Excellent inter-observer agreement was noted for both qualitative assessments. Diagnostic performance at the DNH level showed CLEAR-DESS (4 observers; AUC: 0.90–0.96; sensitivity: 85%–96%; specificity: 88%–94%) significantly outperformed SWI (4 observers; AUC: 0.73-0.85; sensitivity: 65%–70%; specificity: 74%–89%). Similarly, at the patient level, CLEAR-DESS (4 observers; AUC: 0.91–0.96; sensitivity: 91%–94%; specificity: 88%–100%) surpassed SWI (4 observers; AUC: 0.79–0.87; sensitivity: 80%–89%; specificity: 60%–79%). CLEAR-DESS also showed significantly better DNH visualization slices, SNR, and CNR than SWI (all p < 0.001). The 7T CLEAR-DESS sequence provides superior DNH visualization and PD diagnostic performance compared to SWI, indicating its potential as a preferred choice for DNH evaluation.