Benign paroxysmal positional vertigo (BPPV) is believed to occur when dislodged otoconia from the utricle migrate into the semicircular canals. The condition resolves spontaneously or with canalith repositioning procedures in most cases. However, a subset of patients exhibits refractory BPPV that does not respond to conservative treatment, in which case, surgical intervention may need to be considered. We report a case in which a favorable clinical outcome was obtained following left posterior semicircular canal plugging performed in a patient who presented with refractory bilateral posterior canal BPPV that developed following a traffic accident.
The patient was a 75-year-old woman who began suffering from vertigo after she sustained injuries in a motorcycle accident at the age of 73 years. She was diagnosed as having BPPV at a local clinic and underwent repeated canalith repositioning procedures and pharmacotherapy, but failed to show symptomatic improvement. Therefore, two years later, she was referred to our department. Although the recurrent right posterior canal BPPV improved with continued conservative treatment, the left-sided BPPV remained refractory, with persistent severe nystagmus despite repeated repositioning maneuvers. Therefore, we performed left posterior semicircular canal plugging. Postoperatively, the rotational vertigo and nystagmus that could be elicited by the left Dix–Hallpike maneuver resolved completely, accompanied by marked improvement in the subjective symptoms. Video head impulse testing demonstrated a reduction in the vestibulo-ocular reflex gain of the left posterior semicircular canal and the appearance of persistent compensatory eye movements, confirming effective occlusion of the target canal. No postoperative alterations were observed in the functioning of the ipsilateral anterior or lateral semicircular canals.
Semicircular canal plugging is a safe and effective therapeutic option for patients with intractable BPPV who are unresponsive to conservative treatment. Further studies are warranted to elucidate the physiological changes in vestibular function that occur following this procedure.
