The Late Blink Reflex Response in Patients with Thalamic Hemorrhage.
- Author:
Jong Moo PARK
1
;
Ho Jin KIM
;
Chang Ho YUN
;
Yong Seok LEE
;
Jae Kyu ROH
;
Kwang Woo LEE
Author Information
1. Department of Neurology, College of Medicine, Seoul National University, Seoul, Korea.
- Publication Type:Original Article
- Keywords:
Blink reflex;
reflex, Thalamic hemorrhage;
R2 Response;
Crossed cortical acilitation Address for correspondence
- MeSH:
Blinking*;
Brain Stem;
Follow-Up Studies;
Hemorrhage*;
Humans;
Interneurons
- From:Journal of the Korean Neurological Association
1999;17(5):661-667
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
BACKGROUND: This study was designed to understand the possible pathways of R2 responses by testing the blink reflex in patients with a thalamic hemorrhage. METHOD: Blink reflexes were obtained in 11 patients with a thalamic hemorrhage. The mean interval of the first test of the thalamic hemorrhage was 21.7(24.4days, and follow-up tests were performed in 5 patients about 10 months later. RESULTS: All subjects showed normal R1 responses on affected or normal sides. However, R2 responses were abnormal in 9 patients (81.8%). R2 responses were not recorded in 4, and prolonged in 3. Two patients showed both absent and prolonged R2 responses. The abnormal R2 responses were grouped as follows. First, R2 was abnormal bilaterally by the stimulation on the affected side (afferent type, N=4). Second, R2 was abnormal bilaterally by the stimulation on the affected side and abnormal contralaterally by the stimulation on the normal side (mixed type, N=2). Third, R2 was abnormal contralaterally by the stimulation on the affected side (undetermined type, N=2). One showed abnormal R2 bilaterally by the stimulation on the affected and normal side (coma type). On follow-up tests, all showed normalized R2 responses. CONCLUSIONS: Thalamic hemorrhages caused various abnormal R2 responses in blink reflexes, which were normalized in several months. It is suggested that the abnormal R2 responses of thalamic hemorrhage result from the removal of crossed cortical facilitation on brainstem interneurons rather than an interrupted central pathway of the R2 response.
