An animal model of obstructive sleep apnea in rabbit.

OBJECTIVES/HYPOTHESIS An animal model of obstructive sleep apnea (OSA) may help to investigate the pathophysiology of this disorder and develop appropriate treatments. We investigated the feasibility of a rabbit model of OSA. STUDY DESIGN Animal study. METHODS Twelve New Zealand white rabbits were injected at the base of their tongues under endoscopic guidance with liquid silicone (experimental group, n = 6) or normal saline (control group, n = 6). Polysomnography was performed before and after injection. The development of OSA and changes in sleep parameters were compared between the two groups. RESULTS Before injection, all rabbits showed normal breathing during sleep without hypopnea. In the silicone group, the rabbits had a mean of 29.9 ± 6.9 hypopneas/hour and a mean of 10.4 ± 3.1 apneas/hour 1 month after silicone injection and 28.4 ± 6.9 hypopneas/hour and 10.0 ± 3.3 apneas/hour 3 months after silicone injection (P < 0.05). Mean total sleep time decreased from 260.3 ± 70.2 minutes at baseline to 152.5 ± 38.8 minutes 1 month and 206.8 ± 60.3 minutes 3 months after injection, with a decrease in stage II sleep. In the saline group, however, there were no breathing events during sleep. CONCLUSIONS These results show that silicone injections into the tongue base of rabbits can result in OSA.