Double saccadic pulses and macrosaccadic oscillations from a focal brainstem lesion.
Double saccadic pulses (DSP) are saccadic intrusions that consist of an initial saccade away from a fixation followed immediately by a return saccade back to the fixation. DSP have been reported in patients with presumed multiple sclerosis and metabolic encephalopathy. However, DSP have not been described in a circumscribed brain lesion. We report a man who developed almost continuous DSP with intervening macrosaccadic oscillations from a circumscribed lesion in the dorsal pontine tegmentum which extended up to the midbrain level and spared the nucleus raphe interpositus where the pause cells reside. Damage to the projections from the superior colliculus to omnipause neurons and resultant dysfunction of omnipause neuron may be a mechanism of saccadic intrusions and oscillations observed in our patient with a circumscribed brainstem lesion.
Kim
Ji Soo
JS
Department of Neurology, College of Medicine, Seoul National University, Republic of Korea. jisookim@snu.ac.kr
Choi
Kwang-Dong
KD
Oh
Sun-Young
SY
Jeong
Seong-Hae
SH
Oh
Young-Mi
YM
Kim
Hyo-Jung
HJ
Park
Seong-Ho
SH
Ahn
Jin Young
JY
D000328:Adult; D001930:Brain Injuries / Q000150:complications* / Q000473:pathology*; D001933:Brain Stem / Q000473:pathology* / Q000503:physiopathology; D004585:Electrooculography / Q000379:methods; D005403:Fixation, Ocular / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D015835:Ocular Motility Disorders / Q000209:etiology*