Persistent Upbeat Positional Nystagmus in a Patient with Bilateral Posterior Canal Benign Paroxysmal Positional Vertigo

<div>Video-oculographic recording of upbeat nystagmus (maximum slow phase velocity about 9.0°/s) in a straight supine position during the head roll test. A: the moment of the straight supine position and B: the moment of turning the head position from straight to the left ear-down supine position.</div>

Case Reports in Otolaryngology

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Figure 1

Figure 1: Persistent Upbeat Positional Nystagmus in a Patient with Bilateral Posterior Canal Benign Paroxysmal Positional Vertigo 