Insights in Structural and Functional Cortical Connectivity in Neuropathic and Non-Neuropathic Pain
Poster No:
2525
Submission Type:
Abstract Submission
Authors:
Noah Lee1, Martin Cole2, Jennifer Gewandter2, John Markman2, Paul Geha2
Institutions:
1Yale University, New Haven, CT, 2University of Rochester Medical Center, Rochester, NY
First Author:
Co-Author(s):
Introduction:
Chronic back pain (CBP) represents a pervasive and debilitating health issue with substantial societal and economic implications.1 It is estimated that up to 80% of individuals will experience back pain at some point in their lives, and a significant subset of these individuals will go on to develop chronic, persistent symptoms.2 Continuing advancements in neuroimaging techniques have provided a unique opportunity to investigate the interplay between altered brain connectivity and the manifestation of chronic pain states. As neuroimaging studies have shown differences in connectivity measures between neuropathic and non-neuropathic pain, we hope to investigate structural and functional connectivity differences in neuropathic (i.e., back pain with sciatica) and non-neuropathic CBP.
Methods:
We included 49 patients (age: 50 ± 16; female: 49%) with chronic back pain (> 1 year) along with 35 healthy controls (age: 49 ± 16; female: 74%) in this analysis. Out of the chronic back pain patients, 22 (age: 48 ± 17; female: 59%) of them were classified as neuropathic using the Standardized Evaluation of Pain (StEP) test, while 27 (age: 53 ± 16; female: 41%) of them were not. We collected diffusion-weighted, T1w, and rs-fMRI images from all subjects. All data were processed with the Surface-Based Connectivity Integration (SBCI) Pipeline and were confined to the cortex.3 We examined group differences using ANCOVA corrected for age, sex, and BMI. Measures of connectivity tested included white matter-based structural connectivity (tractography, volume of tracts intersecting with cortical surface), seed-based connectivity using the accumbens and thalamus as seeds, coupling of structural-functional connectivity, and connectopy of primary somatosensory area S1.
Results:
Contrary to our hypothesis of presumed differences between neuropathic and non-neuropathic CBP, ANCOVA did not yield any significant results (after correcting for multiple comparisons) using our connectivity measures. We therefore grouped the two CBP phenotypes and compared them to healthy controls. This approach uncovered significant (cluster corrected p-value: 0.03) group differences in the gradient of connectivity between S1 and primary sensory-motor areas and parts of the supplementary motor area (Fig.1).
Conclusions:
Clinical phenotypes do not appear to affect cortical connectivity in sub-groups of CBP. Nevertheless, we did identify differences in connectopy between CBP patients and healthy controls that are not yet reported in the literature. Further analysis will incorporate subcortical areas in our global measures of connectivity.
Modeling and Analysis Methods:
Connectivity (eg. functional, effective, structural) 2
Perception, Attention and Motor Behavior:
Perception: Pain and Visceral 1
Keywords:
FUNCTIONAL MRI
Pain
STRUCTURAL MRI
WHITE MATTER IMAGING - DTI, HARDI, DSI, ETC
1|2Indicates the priority used for review
Provide references using author date format
2. Hoy, D. et al. (2010). The Epidemiology of low back pain. Best practice & research. Clinical Rheumatology, 24(6), 769–781. https://doi.org/10.1016/j.berh.2010.10.002
3. Cole, M. et al. (2021). Surface-Based Connectivity Integration: An atlas-free approach to jointly study functional and structural connectivity. Human brain mapping, 42(11), 3481–3499. https://doi.org/10.1002/hbm.25447