Visual dysfunction of superior colliculus and lateral geniculate nucleus in idiopathic blepharospasm.
Brainstem
Dystonia
Eye-blinking
Human vision
Neuroimaging
Journal
Journal of the neurological sciences
ISSN: 1878-5883
Titre abrégé: J Neurol Sci
Pays: Netherlands
ID NLM: 0375403
Informations de publication
Date de publication:
15 Oct 2024
15 Oct 2024
Historique:
received:
30
04
2024
revised:
06
09
2024
accepted:
13
10
2024
medline:
20
10
2024
pubmed:
20
10
2024
entrez:
19
10
2024
Statut:
aheadofprint
Résumé
The etiology and pathophysiology of idiopathic blepharospasm (BP) are still largely unknown. It has been hypothesized that BP is the consequence of a dysfunction of the basal ganglia loop, although cortical areas, cerebellum, and other brainstem structures may be involved. There is some evidence that the superior colliculus (SC), a sensorimotor brainstem structure, is involved in another adult-onset focal dystonia, the cervical dystonia. To date, there is no data concerning the implication of the SC in BP. Our study aims to investigate the role of the SC in people with idiopathic BP compared to controls using fMRI and a visual stimulation paradigm based on luminance contrast variations. People with idiopathic BP and controls underwent brain fMRI using a standardized protocol, allowing modulation of visual activity in the SC, the lateral geniculate nucleus (LGN), and the primary visual cortex (V1), at increasing luminance levels (1 %, 3 %, 5 %, 9 %). Ten BP women and ten sex- and age-matched controls were enrolled. Compared to controls, the BP group showed no modulation of visual responses at all luminance levels (p < 0.05) in both SC and LGN. In BP, BOLD responses in V1 were significantly lower at 5 % (p = 0.001), and 9 % (p = 0.002) luminance level. Our findings support the concept of SC and LGN dysfunction in idiopathic BP. Brain fMRI, targeting these sub-cortical visual structures, could play a future important role both as a biomarker and in our understanding of the pathophysiology of adult-onset focal dystonias.
Sections du résumé
BACKGROUND
BACKGROUND
The etiology and pathophysiology of idiopathic blepharospasm (BP) are still largely unknown. It has been hypothesized that BP is the consequence of a dysfunction of the basal ganglia loop, although cortical areas, cerebellum, and other brainstem structures may be involved. There is some evidence that the superior colliculus (SC), a sensorimotor brainstem structure, is involved in another adult-onset focal dystonia, the cervical dystonia. To date, there is no data concerning the implication of the SC in BP.
OBJECTIVES
OBJECTIVE
Our study aims to investigate the role of the SC in people with idiopathic BP compared to controls using fMRI and a visual stimulation paradigm based on luminance contrast variations.
METHODS
METHODS
People with idiopathic BP and controls underwent brain fMRI using a standardized protocol, allowing modulation of visual activity in the SC, the lateral geniculate nucleus (LGN), and the primary visual cortex (V1), at increasing luminance levels (1 %, 3 %, 5 %, 9 %).
RESULTS
RESULTS
Ten BP women and ten sex- and age-matched controls were enrolled. Compared to controls, the BP group showed no modulation of visual responses at all luminance levels (p < 0.05) in both SC and LGN. In BP, BOLD responses in V1 were significantly lower at 5 % (p = 0.001), and 9 % (p = 0.002) luminance level.
CONCLUSIONS
CONCLUSIONS
Our findings support the concept of SC and LGN dysfunction in idiopathic BP. Brain fMRI, targeting these sub-cortical visual structures, could play a future important role both as a biomarker and in our understanding of the pathophysiology of adult-onset focal dystonias.
Identifiants
pubmed: 39426359
pii: S0022-510X(24)00408-8
doi: 10.1016/j.jns.2024.123272
pii:
doi:
Types de publication
Journal Article
Langues
eng
Sous-ensembles de citation
IM
Pagination
123272Informations de copyright
Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.
Déclaration de conflit d'intérêts
Declaration of competing interest None.