Related Experiment Video
Updated: Jan 31, 2026

Testing of all Six Semicircular Canals with Video Head Impulse Test Systems
Published on: April 18, 2019
Pulsatile nystagmus secondary to semicircular canal dehiscence
Mohamed Hawwas1, Emily Young2, Virangna Taneja3
1Department of Surgery, Ministry of Health-Dakahlia Directorate, Mansoura, Egypt.
Abstract:
We report the case of a 69-year-old man with a history of mastoidectomy for cholesteatoma, who developed spontaneous spinning vertigo on debridement of his cavity. Subsequent CT confirmed a lateral semicircular canal fistula, which was surgically closed with mastoid cavity obliteration. Following surgery, he developed a spontaneous, pulse-synchronous horizontal pendular nystagmus. We discuss the pathophysiology of this rare clinical sign.
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