Contributions
Abstract: P533
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - Imaging
Background: Multiple sclerosis (MS) causes deficits in information processing speed and memory that have been related to brain atrophy - both overall and in specific regions such as the subcortical nuclei of the medial temporal lobe (MTL) and deep grey matter (DGM). Hemispheric specialization is a well-established attribute of the human brain, but little attention has been paid to hemispheric differences in these regional volumes and how they might relate to patients" cognitive performance on tests differing in verbal vs visual-spatial demand.
Methods: Patients with MS (N=66) were compared with healthy controls (N=31) in terms of their performance on computerized versions of the Symbol Digit Modalities Test, Rey Auditory Verbal Learning Test, and Brief Visual Memory Test; and their left and right volumes for several brain regions: MTL - including the hippocampus, amygdala, and nucleus accumbens; DGM - including the thalamus, pallidum, putamen, and caudate; cortical gray matter; cerebral white matter; and cerebellum. Patients and controls were right handed and were well matched in terms of age, gender, and education. The patient sample included individuals with relapsing (N=25), primary progressive (N=22), and secondary progressive MS (N=19). Length of diagnosis ranged from 1 to 33 year (M=10.7) and disability ratings from 1 to 8.5 (Md=4.75). Regional brain volumes were based on automated segmentation using FreeSurfer applied to MR scans at 3 T and normalized on the basis of intracranial volume.
Results: Patients had significantly lower scores than controls on all cognitive measures and on all but three lateralized regional volumes (left thalamus, left and right hippocampus). Also, with only a few exceptions, patients" performance on each cognitive measure was significantly correlated with both their left- and right-side regional volumes. However, closer examination of these correlations revealed the relationship was often stronger (DR2 ≥ .05) for the right volume than for the corresponding left volume (chi2 = 6.1, df =2, p = .047), regardless of the cognitive test. This was especially true for the regions composing the MTL and DGM.
Conclusion: This asymmetry may indicate a difference in the cognitively-relevant impact of MS on a variety of subcortical nuclei. Its occurrence across a variety of cognitive measures also suggests that the tests used to evaluate cognitive deficits in MS may be insufficiently sensitive to lateralized cognitive dysfunction.
Disclosure:
This work was partially funded by grant RG 4495-A-4 from the National MS Society Scott Belliston, DO: has a fellowship grant from the National MS Society.
Peter Adany, PhD: Nothing to disclose
Phil Lee, PhD: Nothing to disclose
Doug Denney, PhD: Nothing to disclose
Abbey Hughes, PhD: Nothing to disclose
In-Young Choi, PhD: Nothing to disclose
Sharon Lynch, MD: has received grant/research support from Actelion, Bayer, Biogen Idec, Cephalon, Cognition, Eli Lilly, EMD Serono, Genzyme, Novartis, Ono Pharma, Pfizer, Receptos, Genentech, Roche, Sanofi Aventis, Sun Pharma, and Teva Neuroscience.
Abstract: P533
Type: Poster
Abstract Category: Pathology and pathogenesis of MS - Imaging
Background: Multiple sclerosis (MS) causes deficits in information processing speed and memory that have been related to brain atrophy - both overall and in specific regions such as the subcortical nuclei of the medial temporal lobe (MTL) and deep grey matter (DGM). Hemispheric specialization is a well-established attribute of the human brain, but little attention has been paid to hemispheric differences in these regional volumes and how they might relate to patients" cognitive performance on tests differing in verbal vs visual-spatial demand.
Methods: Patients with MS (N=66) were compared with healthy controls (N=31) in terms of their performance on computerized versions of the Symbol Digit Modalities Test, Rey Auditory Verbal Learning Test, and Brief Visual Memory Test; and their left and right volumes for several brain regions: MTL - including the hippocampus, amygdala, and nucleus accumbens; DGM - including the thalamus, pallidum, putamen, and caudate; cortical gray matter; cerebral white matter; and cerebellum. Patients and controls were right handed and were well matched in terms of age, gender, and education. The patient sample included individuals with relapsing (N=25), primary progressive (N=22), and secondary progressive MS (N=19). Length of diagnosis ranged from 1 to 33 year (M=10.7) and disability ratings from 1 to 8.5 (Md=4.75). Regional brain volumes were based on automated segmentation using FreeSurfer applied to MR scans at 3 T and normalized on the basis of intracranial volume.
Results: Patients had significantly lower scores than controls on all cognitive measures and on all but three lateralized regional volumes (left thalamus, left and right hippocampus). Also, with only a few exceptions, patients" performance on each cognitive measure was significantly correlated with both their left- and right-side regional volumes. However, closer examination of these correlations revealed the relationship was often stronger (DR2 ≥ .05) for the right volume than for the corresponding left volume (chi2 = 6.1, df =2, p = .047), regardless of the cognitive test. This was especially true for the regions composing the MTL and DGM.
Conclusion: This asymmetry may indicate a difference in the cognitively-relevant impact of MS on a variety of subcortical nuclei. Its occurrence across a variety of cognitive measures also suggests that the tests used to evaluate cognitive deficits in MS may be insufficiently sensitive to lateralized cognitive dysfunction.
Disclosure:
This work was partially funded by grant RG 4495-A-4 from the National MS Society Scott Belliston, DO: has a fellowship grant from the National MS Society.
Peter Adany, PhD: Nothing to disclose
Phil Lee, PhD: Nothing to disclose
Doug Denney, PhD: Nothing to disclose
Abbey Hughes, PhD: Nothing to disclose
In-Young Choi, PhD: Nothing to disclose
Sharon Lynch, MD: has received grant/research support from Actelion, Bayer, Biogen Idec, Cephalon, Cognition, Eli Lilly, EMD Serono, Genzyme, Novartis, Ono Pharma, Pfizer, Receptos, Genentech, Roche, Sanofi Aventis, Sun Pharma, and Teva Neuroscience.