The results of a pilot study of 21 patients conducted at Mercy Medical Center demonstrated that use of NBI resulted in the diagnosis of pathologically-proven endometriosis among 4 patients whose lesions were missed with visible white light only examination. In addition, the number of confirmed endometriosis lesions increased with the use of NBI in addition to white light. The study also suggested that NBI may assist in discriminating endometriosis from other lesions, thus reducing false positives: one patient had no lesions detected with NBI and the lesions biopsied based on visible white light examination were not endometriosis at pathologic examination.