Subtle Torsional Pendular Nystagmus in Oculopalatal Tremor (OPT) (Figure 1)

This is a 50-year-old woman who presented with imbalance, and MRI demonstrated a right cerebellar cavernous malformation. She underwent surgery to resect the malformation, and post-operatively experienced right hemiparesis and ataxia. Six months after the surgery, balance worsened and vision became "blurry" despite normal afferent function. Exam demonstrated mild torsional pendular nystagmus OU and subtle rhythmic twitching of the right mentalis (not seen in the video). Palatal tremor was also seen, synchronous with the facial muscle twitching. When the patient was asked to gently close her eyes, vertical ocular oscillations (again synchronous with the palatal tremor) were apparent. Even when nystagmus due to oculopalatal tremor (OPT) is subtle or absent, eyelid closure will usually bring out (e.g., palatal tremor without nystagmus is usually seen with progressive ataxia and palatal tremor [PAPT], although rhythmic oscillations can still be brought out with gentle eyelid closure) or accentuate vertical ocular oscillations, a finding that is sometimes referred to as ocular synchrony. MRI T2/FLAIR sequences demonstrated a hyperintense left inferior olivary nucleus (figure), consistent with the theory of olivary hypertrophy, which is thought to generate OPT. ; When pendular nystagmus of unclear origin is appreciated, regardless of whether it is subtle, monocular, disjunctive, dissociated or conjugate, the examiner must have a suspicion for OPT and view the palate at rest. ; [[Number of Figures and legend for each: 1, MRI FLAIR sequence demonstrating a hyperintensity of the left inferior olivary nucleus.; Number of Videos and legend for each: 1, This is a patient with oculopalatal tremor, with subtle nystagmus that increased with eyelid closure. ]] Find case video, CLICK HERE: https://collections.lib.utah.edu/details?id=1279194