Objective: Ocular palatal tremor typically develops following a lesion in the dentato-rubro-olivary pathway (DROP) which is also known as Guillain-Mollaret triangle (GMT). We here describe a variant of this syndrome in which facial muscle twitches are also present.Ocular palatal tremor typically develops following a lesion in the dentato-rubro-olivary pathway (DROP) which is also known as Guillain-Mollaret triangle (GMT). We here describe a variant of this syndrome in which facial muscle twitches are also present.

Background: Guillain-Mollaret triangle connects deep cerebellar nuclei to inferior olive and back, the fibers pass by the red nucleus.
Interruption in the continuity of Guillain-Mollaret triangle results in pseudohypertrophy and spontaneous rhythmic discharges from the inferior olive, Correlating with coarse oscillations of eye and palate.

Method: Ocular palatal tremor uniquely manifested in conjunction with facial twitches in six studied patients. We assessed their eye, palate movements and facial muscle twitches.

Results: Among six patients with ocular palatal tremor, 2 had left eyelid twitches, one had left eyebrow twitches, 2 had lower lip and face twitches, one had neck twitches. All of them had coarse quasi-sinusoidal eye oscillations and palate oscillations. Difference in semiology between ocular palatal tremor and facial muscle twitches suggested that facial muscle twitches were not compensatory or secondary to the eye oscillations.

Conclusion: We describe a variant of ocular palatal tremor with facial muscle twitches. Of note, all the involved facial muscles have an embryological origin in the second pharyngeal pouch however they don’t share the same anatomical correlate in the mature brain. We speculate the etiology of this phenomenon in the maladaptive state of the brain.

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