Late attacks of paroxysmal ocular tilt reaction.

A 54-year-old patient had a right mesodiencephalic hemorrhage in 1992, with residual double vision until 2000. He was symptom-free until 2010, when he developed fluctuating diplopia. We observed paroxysmal attacks of a right ocular tilt reaction (OTR) (video at Neurology.org), whereas in the interval he had a left OTR. MRI showed a calcification of the preexisting lesion (figure). The attacks are apparently caused by an excitation of the right interstitial nucleus of Cajal (INC), as supported by the effectiveness of carbamazepine (100mg b.i.d.). The delayed onset can be explained by a reorganization of the excitatory and inhibitory synapses found in the INC.