US Contrast Agent Arrival Time Difference Ratio for Benign versus Malignant Subpleural Pulmonary Lesions

Area of Science:

• Medical Imaging
• Pulmonology
• Diagnostic Ultrasound

Background:

• Ultrasound (US) is valuable for diagnosing subpleural pulmonary lesions (SPLs).
• Existing US indicators for SPLs have limitations in differentiating benign from malignant cases.
• Contrast-enhanced (CE) US offers potential for improved diagnostic accuracy.

Purpose of the Study:

• To propose and validate a novel contrast-enhanced (CE) US indicator for the differential diagnosis of benign and malignant subpleural pulmonary lesions (SPLs).
• To compare the diagnostic performance of the new CE US indicator against existing criteria.

Main Methods:

• A prospective study enrolled 902 participants with SPLs, divided into developmental and validation cohorts.
• Five CE US indicators were evaluated, with the arrival time (AT) difference ratio selected as optimal.
• The AT difference ratio's performance was compared to existing criteria using the area under the receiver operating characteristic curve (AUC) in the validation cohort.

Main Results:

• The AT difference ratio demonstrated high diagnostic accuracy for differentiating benign and malignant SPLs across all lesion sizes.
• In the validation cohort, the AT difference ratio achieved AUCs of 0.91 (overall), 0.97 (large lesions), and 0.77 (small lesions).
• These AUCs were significantly higher than those obtained using existing CE US diagnostic criteria.

Conclusions:

• The US contrast agent arrival time difference ratio is a superior indicator for differentiating benign and malignant subpleural lesions.
• This novel indicator offers improved diagnostic performance compared to current CE US criteria.
• The findings support the clinical utility of the AT difference ratio in the evaluation of SPLs.