Objective: Determine the sensitivity and specificity of optical coherence tomography (OCT) as an adjunct to colposcopy in the detection of cervical intraepithelial neoplasia (CIN) grade 2 or higher in a real-time clinical evaluation.

Background: Optical coherence tomography (OCT) uses infrared light similar to ultrasound pulse-echo imaging. Image resolution is optimal in the 1-to-3-mm range. This study is the third in our series of OCT investigations and our first real-time clinical trial. The study was conducted at the Peking University Shenzhen Hospital, Shenzhen, China.

Methods: Nonpregnant women 18 years or older with abnormal cervical cytologic findings or a positive high-risk human papillomavirus test result were recruited. Women were assessed; and diagnoses, recorded by cervical quadrant first with colposcopy, followed by colposcopic directed OCT. A biopsy of the abnormal areas was performed. In normal quadrants, biopsy specimens were obtained at the 2-, 4-, 8-, and 10-o'clock positions at the squamocolumnar junction depending on the quadrant. An endocervical curettage was also done. Individual OCT diagnoses were paired with colposcopic impressions and biopsy specimens to assess its role as a paired secondary screen. Data were analyzed using generalized estimating equations to control for correlation within a woman.

Results: One thousand two hundred thirty-seven paired diagnoses from 299 women were analyzed. Median age was 36 years. Ninety-six women (8%) had a diagnosis of CIN 2 or higher. Evaluation by quadrant showed that the sensitivity for CIN 2 or higher decreased by adding OCT to colposcopy, but the specificity increased from 83% to 93%.

Conclusions: We continue to try to improve sensitivity by improving the near-infrared light source, decreasing the scan time to 8 frames per second, and using a larger diameter (5 mm) fiberoptic probe with a newly designed application specific probe sheath.