Involvement of the anterior semicircular canal in posttraumatic benign paroxysmal positioning vertigo.

OBJECTIVE

To study the involvement of the different semicircular canals in posttraumatic benign paroxysmal positioning vertigo (BPPV) with special reference to the anterior canal (AC).

STUDY

DESIGN

Retrospective review.

SETTING

Tertiary referral center.

PATIENTS: Seventy-four BPPV patients.

INTERVENTIONS: Neurotologic assessment with video-oculography; treatment of BPPV with the canalith repositioning procedure appropriate for the affected semicircular canal.

MAIN OUTCOME MEASURES: Number of patients with AC, posterior canal (PC), horizontal canal (HC), and multiple-canal involvement in posttraumatic versus idiopathic BPPV.

RESULTS

85.1% of patients were classified as idiopathic BPPV, whereas 14.9% had a history of posttraumatic BPPV. The prevalence of AC BPPV was significantly higher in the posttraumatic group (27.3%) compared with that in the idiopathic group (3.2%; Fisher's exact test: p = 0.021). Multiple-canal (combined) BPPV was observed more frequently after head trauma (27.3%) compared with the idiopathic form of the disorder (1.6%; p = 0.009). In particular, the risk for combined AC/PC BPPV was greater in posttraumatic than idiopathic cases (odds ratio, 13.78; 95% confidence interval, 1.13-167.8). No significant differences were observed for the involvement of the PC and HC between the two groups. Two cases of combined AC/PC BPPV are presented with particular respect to the underlying trauma mechanism.

CONCLUSION

Head trauma is a risk factor for AC and combined BPPV, in particular AC/PC BPPV. Involvement of the AC should especially be considered in patients who experienced head trauma resulting in a nonupright position of the body.