Journal of Fertilization: In Vitro - IVF-Worldwide, Reproductive Medicine, Genetics & Stem Cell Biol
Open Access

Abstract

Synchrotron Imaging of Ovaries Ex Vivo

Upekha Basnayaka, Dean Chapman, Gregg Adams DVM, Tomasz Wysokinski, George Belev, Rani Kanthan, Rajni Chibbar, Robert Lewis, Naoto Yagi, Kentaro Uesugi, Masato Hoshino and Angela Baerwald

Background: Conventional 2-dimensional ultrasonography is limited in its ability to detect ovarian microanatomy. The objective of this study was to determine if biomedical synchrotron techniques would be effective for imaging ovarian microanatomy, including ovarian follicles, corpora lutea, and the oocyte.

Methods: A prospective, observational study was conducted at the Canadian Light Source to compare ovarian imaging ex vivo using propagation-based computed tomography (PB-CT) synchrotron imaging, ultrasonography, and histology. Bovine (n=4) and human (n=4) ovaries were imaged fresh or formalin-fixed. The effectiveness of Talbot grating interferometry computed tomography (TGI-CT) synchrotron imaging to image preserved bovine (n=1) and human (n=1) ovaries were evaluated at the SPring-8 synchrotron, Japan.

Results: All antral follicles ≥ 2 mm and corpora lutea detected with ultrasonography were identified with PBCT. Mean follicle and luteal diameters did not differ among PB-CT, ultrasonography, and histology. The smallest follicle detected was superior with PB-CT (0.9 ± 0.4 mm) than ultrasonography (2.2 ± 0.2 mm, P<0.05). PB-CT, but not ultrasonography, allowed the detection of follicle wall cell layers (P<0.05). TGI-CT provided greater contrast for evaluating follicles, corpora lutea, and vasculature than PB-CT and ultrasonography. High contrast spherical structures resembling cumulus-oocyte complexes were detected with PB-CT and TGI-CT; oocytes were only detected with TGI-CT.

Conclusion: PB-CT was as effective as ultrasonography for measuring follicle and luteal diameters and superior to ultrasonography for visualizing follicles <2 mm, follicle wall cell layers, and cumulus-oocyte complexes. TGI-CT appears to provide the greatest resolution for imaging ovarian anatomy compared to ultrasonography and PB-CT. Phase contrast CT Synchrotron can be used as a model for developing high-resolution tools for imaging human ovaries.