Jean-Michel Lemée1, Eva Chinier2, Pauline Ali3, Matthieu Labriffe4, Aram Ter Minassian5, Mickael Dinomais3. 1. Département de neurochirurgie, CHU Angers, 49933 Angers, France. Electronic address: lemee.jmichel@wanadoo.fr. 2. Département de médecine physique et de réadaptions, CHU Angers-Capucins, 49933 Angers, France. 3. Département de médecine physique et de réadaptions, CHU Angers-Capucins, 49933 Angers, France; EA7315, laboratoire Angevin de recherche en ingénierie des systèmes (LARIS), université d'Angers, 49000 Angers, France. 4. Département de radiologie, CHU Angers, 49933 Angers, France. 5. EA7315, laboratoire Angevin de recherche en ingénierie des systèmes (LARIS), université d'Angers, 49000 Angers, France; Pôle d'anesthésie réanimation, CHU Angers, 49933 Angers, France.
Abstract
OBJECTIVE: To evaluate the relationship between neural (re)organization of the somatosensory cortex and impairment of sensory function (2-point discrimination [2PD]) in individuals with unilateral cerebral palsy. METHODS: We included 21 individuals with unilateral cerebral palsy. 2PD thresholds were evaluated on thumb pads, and activation of the somatosensory cortex was recorded by functional MRI (fMRI) during passive movements of the affected hand. A lateralization index (LI) was calculated for the primary sensory (S1) and secondary sensory (S2) cortices and the correlation between the LI and 2PD thresholds was analysed. RESULTS: We found a significant negative correlation between the 2PD thresholds and the S2 LI (r=-0.5, one-tailed P-value=0.01) and a trend towards a negative correlation with the S1 LI (r=-0.4, one-tailed P-value=0.05). CONCLUSION: High levels of activation in the contralesional hemisphere were associated with high levels of sensory impairment in individuals with unilateral cerebral palsy. The interhemispheric (re)organization of the somatosensory system may not effectively compensate for somatosensory impairment.
OBJECTIVE: To evaluate the relationship between neural (re)organization of the somatosensory cortex and impairment of sensory function (2-point discrimination [2PD]) in individuals with unilateral cerebral palsy. METHODS: We included 21 individuals with unilateral cerebral palsy. 2PD thresholds were evaluated on thumb pads, and activation of the somatosensory cortex was recorded by functional MRI (fMRI) during passive movements of the affected hand. A lateralization index (LI) was calculated for the primary sensory (S1) and secondary sensory (S2) cortices and the correlation between the LI and 2PD thresholds was analysed. RESULTS: We found a significant negative correlation between the 2PD thresholds and the S2 LI (r=-0.5, one-tailed P-value=0.01) and a trend towards a negative correlation with the S1 LI (r=-0.4, one-tailed P-value=0.05). CONCLUSION: High levels of activation in the contralesional hemisphere were associated with high levels of sensory impairment in individuals with unilateral cerebral palsy. The interhemispheric (re)organization of the somatosensory system may not effectively compensate for somatosensory impairment.