OBJECTIVE: To investigate horizontal saccade changes according to disease stage in patients with progressive supranuclear palsy (PSP). METHODS: We studied visually and memory guided saccades (VGS and MGS) in 36 PSP patients at various disease stages, and compared results with those in 66 Parkinson's disease (PD) patients and 58 age-matched normal controls. RESULTS: Both vertical and horizontal saccades were affected in PSP patients, usually manifesting as "slow saccades" but sometimes as a sequence of small amplitude saccades with relatively well preserved velocities. Disease progression caused saccade amplitude reduction in PSP but not PD patients. In contrast, VGS and MGS latencies were comparable between PSP and PD patients, as were the frequencies of saccades to cue, suggesting that voluntary initiation and inhibitory control of saccades are similar in both disorders. Hypermetria was rarely observed in PSP patients with cerebellar ataxia (PSPc patients). CONCLUSIONS: The progressively reduced accuracy of horizontal saccades in PSP suggests a brainstem oculomotor pathology that includes the superior colliculus and/or paramedian pontine reticular formation. In contrast, the functioning of the oculomotor system above the brainstem was similar between PSP and PD patients. SIGNIFICANCE: These findings may reflect a brainstem oculomotor pathology.
OBJECTIVE: To investigate horizontal saccade changes according to disease stage in patients with progressive supranuclear palsy (PSP). METHODS: We studied visually and memory guided saccades (VGS and MGS) in 36 PSPpatients at various disease stages, and compared results with those in 66 Parkinson's disease (PD) patients and 58 age-matched normal controls. RESULTS: Both vertical and horizontal saccades were affected in PSPpatients, usually manifesting as "slow saccades" but sometimes as a sequence of small amplitude saccades with relatively well preserved velocities. Disease progression caused saccade amplitude reduction in PSP but not PDpatients. In contrast, VGS and MGS latencies were comparable between PSP and PDpatients, as were the frequencies of saccades to cue, suggesting that voluntary initiation and inhibitory control of saccades are similar in both disorders. Hypermetria was rarely observed in PSPpatients with cerebellar ataxia (PSPc patients). CONCLUSIONS: The progressively reduced accuracy of horizontal saccades in PSP suggests a brainstem oculomotor pathology that includes the superior colliculus and/or paramedian pontine reticular formation. In contrast, the functioning of the oculomotor system above the brainstem was similar between PSP and PDpatients. SIGNIFICANCE: These findings may reflect a brainstem oculomotor pathology.
Authors: Jessica Wunderlich; Anna Behler; Jens Dreyhaupt; Albert C Ludolph; Elmar H Pinkhardt; Jan Kassubek Journal: J Neurol Date: 2021-03-21 Impact factor: 4.849