Monitoring of bone repair process by in-line phase-contrast CT: evaluation of osteoporotic bone repair in mice

Abstract

In-line phase-contrast CT (IPCT) provides high sensitivity to analyze biological tissue structure. Here, we applied IPCT combined with a single-distance phase retrieval to quantify the bone repair process in mice.Female mice underwent ovariectomy or sham-operated at 10 weeks of age. Two weeks later, a 0.5-mm hole was created at a tibial diaphysis, and the ovariectomized mice were subdivided into OVX and OVX/EET groups. The OVX/EET mice received the 14,15-epoxyeicosatrienoic acid. In-vivo IPCT was performed on postoperative days 3, 7 and 11 in SPring-8 radiation facility.No between-group difference was found in bone repair until postoperative day 7. On the day 11, however, mineral density histogram shows the peak at a lower value in OVX than in sham. Bone volume fraction and mean mineral density were significantly higher in OVX/EET than in OVX, showing the improved bone repair. Thus, IPCT may have the potential to evaluate bone repair dynamics.