Optical imaging as an adjunct to sonograph in differentiating benign from malignant breast lesions

The role of near infrared (NIR) diffusive light imaging as an adjunct to ul trasound in differentiating benign from malignant lesions was evaluated in 27 mammography patients with infiltrating ductal carcinomas, apocrine metap lasia, fibroadenomas, radial scar and ductal hyperplasia, cysts, and normal tissues. Conventional ultrasound/mammography images were graded based on B I-RADS assessment categories. The spatial NIR measurements were made at wav elengths of 750 and 830 nm. Functional images, such as relative changes of deoxyhemoglobin (deoxyHb) and total blood concentration, were estimated fro m the dual wavelength measurements. Maximum relative deoxyHb and blood conc entration changes were measured, and spatial correlation of masses in relat ive deoxyHb and blood concentration images for each breast were calculated. For the five biopsy proven benign lesions, ultrasound/mammography diagnose s were suspicious for malignancy (four cases) and highly suspicious for mal ignancy (one case). Four lesions showed less than 1.0 V maximum deoxyHb and less than 1.5 V maximum blood concentration levels on average and spatial image correlation showed no correlated masses in both deoxyHb and blood con centration images. For the four biopsy proven malignant lesions, ultrasound /mammography diagnoses were highly suspicious for malignancy. Maximum deoxy Hb and blood concentration changes were greater than 2.9 V on average excep t one lesion which showed smaller deoxyHb signal (maximum 0.85 V) but the d eoxyHb mass and blood concentration mass were highly correlated. (C) 2000 S ociety of Photo-Optical Instrumentation Engineers. [S1083-3668(00)00502-5].