An animal model of recurrent vertigo caused by labyrinthine fistula

RAO Xiuli; YIN Shihua; HOU Tao; ZHU Ziang; LONG Ji

doi:10.3969/j.issn.1672-2922.2016.01.024

Abstract：Objective To produce a model of recurrent vertigo caused by labyrinthine fistula using guinea pigs that can be used to study mechanisms of vestibular compensation in recurrent vertigo. Methods Thirty adult guinea pigs were randomly divided into three groups to receive unilateral labyrinthectomy (group A), labyrinthine fistula simulation and pneu-matic otoscopy treatment (group B) or labyrinthine fistula simulation only (group C). The treatment in group B involved ap-plying pressure to the external auditory canal once a day. Imbalance indicators were observed and recorded at postoperative 0h, 24h, 48h, 1w, 2w and 3w respectively, including frequency of spontaneous nystagmus, head deviation and imbalance be-havior scores. Results Imbalance indicators in group B were significantly different compared with other groups at all same time points, except 0h. Within the same group, imbalances symptoms gradually reduced over time and eventually disap-peared, although the change in group B was not as dramatic as in the other two groups. At 48 hours after surgery, spontane-ous nystagmus had stopped in all three groups, although nystagmus was still detectable in group B upon applying pressure in the external auditory canal of the operation ear (5-6 beats/15 seconds). Two weeks after surgery, imbalance symptoms in groups A and C were no more present, but head deviation and other imbalance symptoms could still be observed in group B, with continued nystagmus (5-6 beats/15 seconds) on external auditory canal pressure, which persisted until three weeks af-ter surgery. Conclusion 1. Labyrinthine fistula simulation with ear canal pressure via pneumatic otoscopy can be used to produce a model of vertigo in guinea pigs. 2. Recurrent/persistent vertigo can be produced in this model of vertigo.