Network Effects of Brain Lesions Causing Central Poststroke Pain

Area of Science:

• Neuroscience
• Neurology
• Medical Imaging

Background:

• Central poststroke pain (CPSP) is a debilitating condition resulting from stroke-induced brain lesions.
• The underlying neural mechanisms and specific brain networks involved in CPSP remain incompletely understood.
• Identifying these networks is crucial for developing effective therapeutic strategies.

Purpose of the Study:

• To determine if lesions causing CPSP exhibit a unique brain connectivity profile.
• To investigate the association between these specific connections and metabolic changes in the brain.
• To assess if this identified network aligns with established neuromodulation targets for pain management.

Main Methods:

• Utilized two independent lesion datasets, including subcortical and thalamic lesions with metabolic imaging (18F-FDG PET-CT).
• Assessed functional connectivity using a normative connectome (n=1,000) to identify lesion-specific connections.
• Explored therapeutic relevance by comparing the network with brain stimulation data and prospectively targeting it with repetitive transcranial magnetic stimulation (rTMS).

Main Results:

• Lesions causing CPSP demonstrated a consistent, specific pattern of brain connectivity across both datasets (spatial r=0.82).
• Connectivity differences correlated significantly with postlesion metabolism (r=-0.48).
• The identified pain network aligned with variability in pain improvement from existing neuromodulation targets and rTMS treatment (p<0.05), with 6/7 patients showing CPSP improvement after prospective rTMS targeting.

Conclusions:

• Lesions associated with central poststroke pain are linked to a distinct brain network.
• This network exhibits characteristic metabolic abnormalities and represents a promising target for neuromodulation therapies.
• Repetitive transcranial magnetic stimulation (rTMS) applied to this network shows significant potential for alleviating CPSP.