Contributions
Abstract: P1105
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - Neuropsychology
Background: Cerebellar damages occur early in multiple sclerosis (MS) and could be responsible for cognitive impairment. However, symptoms are difficult to evaluate at this stage of the disease. Eyetracking is a reliable and simple mean to evaluate both subtle cerebellar symptoms and cognitive impairment associated with morphological alterations in the cerebellum.
Objectives: To compare cognitive pattern and posterior cerebellar grey matter (GM) damages in patients with and without cerebellar symptoms as determined by saccadic abnormalities, within the first year after a clinically isolated syndrome (CIS), and healthy subjects (HS).
Methods: Twenty-eight patients and 12 HS underwent an eyetracking protocol. Cerebellar impairment was defined by registration of saccadic intrusions and/or at least 10% of dysmetria at oculomotor (OM) recording. Visually-guided (VGS), memory-guided (MGS) and antisaccade (AS) paradigms were used to assess respectively attention, working memory and inhibition and compared to classical neuropsychological assessment. GM volume in posterior cerebellar lobules (VI to VIIIb) was estimated using 3T magnetic resonance imaging including 3D T1 weighted images.
Results: Sixteen patients fulfilled saccadic criteria for cerebellar impairment. Patients with cerebellar symptoms (PwC) performed worse on memory-guided saccade latencies and error rate and had impaired working memory, executive functions and information processing speed (IPS) z scores compared to patients without cerebellar symptoms (PwNC). IPS was correlated with AS error rate in all patients and VGS error rate and MGS final eye position ratio in cerebellar patients. PwNC had increased GM volume than HS and PwC in most of the cerebellar posterior lobules. Left Crus I GM volume was correlated with visually guided saccades gain (R=0.69; p=0.003) only in PwC subgroup.
Conclusion: Eyetracking and especially memory-guided saccade paradigm is a sensitive and reliable tool to assess cognitive dysfunctions in early MS and differentiates cerebellar from non-cerebellar patients. In CIS patients, cerebellar symptoms provide a specific cognitive profile with more working memory, executive functions and IPS impairment. GM alterations seemed more pronounced in PwC than in PwNC suggesting a potential susceptibility to early neurodegeneration.
Disclosure: Pr Brochet, Dr Ruet and Dr Ouallet or their intitution received reserach grants and/or consulting fees from Biogen-Idec, Bayer-Healthcare, Novartis, Genzyme, Roche, Medday, Merck-Serono and Teva
A. Moroso received research grant from the Fondation pour la Recherche Médicale (DEA20140630564)
Abstract: P1105
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - Neuropsychology
Background: Cerebellar damages occur early in multiple sclerosis (MS) and could be responsible for cognitive impairment. However, symptoms are difficult to evaluate at this stage of the disease. Eyetracking is a reliable and simple mean to evaluate both subtle cerebellar symptoms and cognitive impairment associated with morphological alterations in the cerebellum.
Objectives: To compare cognitive pattern and posterior cerebellar grey matter (GM) damages in patients with and without cerebellar symptoms as determined by saccadic abnormalities, within the first year after a clinically isolated syndrome (CIS), and healthy subjects (HS).
Methods: Twenty-eight patients and 12 HS underwent an eyetracking protocol. Cerebellar impairment was defined by registration of saccadic intrusions and/or at least 10% of dysmetria at oculomotor (OM) recording. Visually-guided (VGS), memory-guided (MGS) and antisaccade (AS) paradigms were used to assess respectively attention, working memory and inhibition and compared to classical neuropsychological assessment. GM volume in posterior cerebellar lobules (VI to VIIIb) was estimated using 3T magnetic resonance imaging including 3D T1 weighted images.
Results: Sixteen patients fulfilled saccadic criteria for cerebellar impairment. Patients with cerebellar symptoms (PwC) performed worse on memory-guided saccade latencies and error rate and had impaired working memory, executive functions and information processing speed (IPS) z scores compared to patients without cerebellar symptoms (PwNC). IPS was correlated with AS error rate in all patients and VGS error rate and MGS final eye position ratio in cerebellar patients. PwNC had increased GM volume than HS and PwC in most of the cerebellar posterior lobules. Left Crus I GM volume was correlated with visually guided saccades gain (R=0.69; p=0.003) only in PwC subgroup.
Conclusion: Eyetracking and especially memory-guided saccade paradigm is a sensitive and reliable tool to assess cognitive dysfunctions in early MS and differentiates cerebellar from non-cerebellar patients. In CIS patients, cerebellar symptoms provide a specific cognitive profile with more working memory, executive functions and IPS impairment. GM alterations seemed more pronounced in PwC than in PwNC suggesting a potential susceptibility to early neurodegeneration.
Disclosure: Pr Brochet, Dr Ruet and Dr Ouallet or their intitution received reserach grants and/or consulting fees from Biogen-Idec, Bayer-Healthcare, Novartis, Genzyme, Roche, Medday, Merck-Serono and Teva
A. Moroso received research grant from the Fondation pour la Recherche Médicale (DEA20140630564)