Colposcope device and method for measuring areas of cervical lesions

摘要

The area of a three-dimensional lesion on a cervix is determined from a two-dimensional image thereof produced by a digital colposcope. A stored reference cervix reflectance map including slant angles and corresponding gray scale intensity levels represents a reference cervix, and is obtained using a shape-assuming target including thereon an array of circular spots of a first reflectivity and a stiff target having thereon a first circular spot of the first reflectivity and a second circular spot of a second reflectivity. An identical stiff target is placed on the cervix, and a two-dimensional image of the lesion and the stiff target is obtained from the digital colposcope. Resulting intensities of the two-dimensional image are calibrated to the gray scale of a standard target reflectance map, and the calibrated intensities of the two-dimensional image are correlated to the intensities of the reference cervix reflectance map to determine slant angles of predetermined points of the cervix. Pixel dimensions of each pixel in the lesion then are corrected in accordance with the slant angles. The lesion area is computed by summing the areas of the pixels with corrected dimensions.