Preliminary report: saccade analysis in acute Graves' ophthalmopathy.

A prospective study on the saccadic properties of 10 patients with acute Graves' ophthalmopathy (GO) compared to 10 healthy individuals was performed using the induction scleral search coil. No significant changes were observed among six patients with moderate disease. In four patients suffering from optic nerve compression, however, a substantial decrease of saccadic velocity and related parameters was detected. The absence of saccadic changes in earlier moderate stages of GO seems to be based on adaptation of the central saccadic generator. The velocity reduction in connection with a marked elevation of intraorbital pressure could be indicative of paretic motoneuron disturbances.