Optical diagnosis of cervical intraepithelial neoplasm (CIN) using polarization-sensitive optical coherence tomography

We present a polarization-sensitive optical coherence tomography (PS-OCT) technique that can quantify the polarization changes (the degrees of circular polarization, DOCP) caused by the scattering changes induced by cervical intraepithelial neoplasia (CIN). The axial and lateral resolutions of our PS-OCT system are 13 microm and 15 microm, respectively. Uterine cervical conization tissue samples from 18 patients were examined, and 71 areas were imaged for in vitro studies; about 2-4 areas per sample were imaged and processed for diagnosis. The scanned areas had a size of 2 mm (axial) X 2 mm (lateral) X 4 mm (transversal). We quantified the slope of the axial decay of the DOCP signal near the cervical epithelium by a linear fitting procedure. The excised samples were then investigated by two pathologists, and their histological findings were later compared with the PS-OCT results. Our results show that the sensitivity and specificity are 94.7% and 71.2%, respectively.