Abstract
Neuroimaging studies have documented brain structural alterations induced by chronic pain, particularly in gray matter volume. However, the effects of trigeminal neuralgia (TN), a severe paroxysmal pain disorder, on cortical morphology are not yet known. In this study, we recruited 30 TN patients and 30 age-, and gender-matched healthy controls (HCs). Using Computational Anatomy Toolbox (CAT12), we calculated and compared group differences in cortical thickness, gyrification, and sulcal depth with two-sample t tests (p < 0.05, multiple comparison corrected). Relationships between altered cortical characteristics and pain intensity were investigated with correlation analysis. Compared to HCs, TN patients exhibited significantly decreased cortical thickness in the left inferior frontal, and left medial orbitofrontal cortex; decreased gyrification in the left superior frontal cortex; and decreased sulcal depth in the bilateral superior frontal (extending to anterior cingulate) cortex. In addition, we found significantly negative correlations between the mean cortical thickness in left medial orbitofrontal cortex and pain intensity, and between the mean gyrification in left superior frontal cortex and pain intensity. Chronic pain may be associated with abnormal cortical thickness, gyrification and sulcal depth in trigeminal neuralgia. These morphological changes might contribute to understand the underlying neurobiological mechanism of trigeminal neuralgia.
Highlights
Neuroimaging studies have documented brain structural alterations induced by chronic pain, in gray matter volume
Based on the voxel-based morphometry (VBM), Obermann et al.[7] found decreased gray matter volume in trigeminal neuralgia (TN) patients, which were mainly located in the dorsolateral prefrontal cortex, anterior cingulate cortex (ACC), primary/secondary somatosensory and orbitofrontal cortices, thalamus, insula, and cerebellum compared with controls
We found no significant differences between the TN and healthy controls (HCs) groups in age, gender, education and total intracranial volume (Table 1)
Summary
Neuroimaging studies have documented brain structural alterations induced by chronic pain, in gray matter volume. Chronic pain may be associated with abnormal cortical thickness, gyrification and sulcal depth in trigeminal neuralgia. These morphological changes might contribute to understand the underlying neurobiological mechanism of trigeminal neuralgia. Based on the voxel-based morphometry (VBM), Obermann et al.[7] found decreased gray matter volume in TN patients, which were mainly located in the dorsolateral prefrontal cortex, anterior cingulate cortex (ACC), primary/secondary somatosensory and orbitofrontal cortices, thalamus, insula, and cerebellum compared with controls. Gyrification and sulcal depth, another two morphological characteristics, that are thought to be parallel to cortical thickness[19,20], have fewer been investigated in TN patients, except one study of Wang et al.[21], which reported significant reductions of local gyrification index in the left insular cortex. The exploration of cortical morphology might provide more accurate and reliable information about underling neurophysiological mechanisms related to chronic pain
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
