Novel near-infrared spectroscopy–intravascular ultrasound-based deep-learning methodology for accurate coronary computed tomography plaque quantification and characterization

AIMS: Coronary computed tomography angiography (CCTA) is inferior to intravascular imaging in detecting plaque morphology and quantifying plaque burden. We aim to, for the first time, train a deep-learning (DL) methodology for accurate plaque quantification and characterization in CCTA using near-infrared spectroscopy–intravascular ultrasound (NIRS–IVUS). METHODS AND RESULTS: Seventy patients were prospectively recruited who underwent CCTA and NIRS–IVUS imaging. Corresponding cross sections were matched using an in-house developed software, and the estimations of NIRS–IVUS for the lumen, vessel wall borders, and plaque composition were used to train a convolutional neural network in 138 vessels. The performance was evaluated in 48 vessels and compared against the estimations of NIRS–IVUS and the conventional CCTA expert analysis. Sixty-four patients (186 vessels, 22 012 matched cross sections) were included. Deep-learning methodology provided estimations that were closer to NIRS–IVUS compared with the conventional approach for the total atheroma volume (Δ(DL-NIRS–IVUS): −37.8 ± 89.0 vs. Δ(Conv-NIRS–IVUS): 243.3 ± 183.7 mm3, variance ratio: 4.262, P < 0.001) and percentage atheroma volume (−3.34 ± 5.77 vs. 17.20 ± 7.20%, variance ratio: 1.578, P < 0.001). The DL methodology detected lesions more accurately than the conventional approach (Area under the curve (AUC): 0.77 vs. 0.67, P < 0.001) and quantified minimum lumen area (Δ(DL-NIRS–IVUS): −0.35 ± 1.81 vs. Δ(Conv-NIRS–IVUS): 1.37 ± 2.32 mm(2), variance ratio: 1.634, P < 0.001), maximum plaque burden (4.33 ± 11.83% vs. 5.77 ± 16.58%, variance ratio: 2.071, P = 0.004), and calcific burden (−51.2 ± 115.1 vs. −54.3 ± 144.4, variance ratio: 2.308, P < 0.001) more accurately than conventional approach. The DL methodology was able to segment a vessel on CCTA in 0.3 s. CONCLUSIONS: The DL methodology developed for CCTA analysis from co-registered NIRS–IVUS and CCTA data enables rapid and accurate assessment of lesion morphology and is superior to expert analysts (Clinicaltrials.gov: NCT03556644).