Precision of automatic measurements of pigmented skin lesion parameters with a MelaFind (TM) multispectral digital dermoscope

The purpose of this study was to assess the precision of automatic computer ized measurement of parameters that may be useful in the differentiation of malignant melanoma from benign pigmented skin lesions, and also to determi ne the feasibility of quantitative monitoring of skin lesions over time. Te n independent sequences of images were acquired with a MelaFind multispectr al digital dermoscope for each of 12 benign or malignant pigmented skin les ions. The sequences of images were processed automatically to provide 10 in dependent measurements of the Various parameters for each lesion. Parameter s included lesion area, greatest 'diameter', perimeter, reflectance and asy mmetry. The precision of each parameter determination was computed from the mean and standard deviation of the 10 measurements of that parameter. The relative errors in determining the lesion area,'diameter' and perimeter wer e found to be 6%, 3% and 4%, respectively. Other lesion parameters that are used in differentiating melanomas from benign skin lesions were also analy sed as a function of wavelength. In the blue band (about 430 nm) the relati ve error was about 7% for the mean lesion reflectance and about 7% for the asymmetry parameter. These results demonstrate the feasibility of using Mel aFind for objective quantitative monitoring of changes in pigmented skin le sions over time. As suggested by some studies, such information is useful i n the early detection of malignant melanoma. The results show that paramete rs obtained automatically from MelaFind images are sufficiently precise to allow pertinent parameters to be used to classify pigmented skin lesions. ( C) 2000 Lippincott Williams & Wilkins.