In vivo evaluation of endometrium through dual-modality intrauterine endoscopy

Female infertilities are highly associated with poor endometrial receptivity. A receptive endometrium is generally characterized by the normal uterine cavity, intact endometrial surface, appropriate endometrial thickness, and echo pattern. Acquiring comprehensive structural information is the prerequisite of endometrium assessment, which is beyond the ability of any single-modality imaging method. In this paper, we introduce a custom-made intrauterine dual-modality (OCT/ultrasound) endoscopic imaging system and achieve in vivo imaging of rabbit uteri, for the first time to our knowledge. The endometrial features of the injured uteri in both ultrasonic and OCT images are consistent with their corresponding pathology. The quantified parameters, including uterine thickness and endometrial surface roughness, show the correlation with the endometrial injury degree but with poor performance for injury classification. The combination of these parameters was proved to assess the degrees of endometrial injury more accurately. Our work shows the potential of the dual-modality system to be translated into a clinical tool, providing multiple quantitative imaging information and helping evaluate the endometrial receptivity and diagnose infertility.