PO-15 | Disclosing somatosensory system alterations in trigeminal neuralgia

Gianfranco De Stefano, Daniel Litewczuk, Enrico Evangelisti, Giuseppe Di Pietro, Pietro Falco, Eleonora Galosi, Caterina Leone, Francesca Caramia, Andrea Truini, Giulia Di Stefano | Department of Human Neuroscience, Sapienza University of Rome, Italy

Background: Trigeminal neuralgia (TN) is a unique neuropathic pain condition in which standard neurological examination and conventional neurophysiological testing typically fail to detect alterations in the somatosensory system. This study aimed to investigate morphological changes within the central somatosensory system of TN patients using high-resolution MRI, and to explore associations with clinical characteristics.

Methods: We prospectively enrolled consecutive patients with a confirmed diagnosis of TN who presented at the Center for Neuropathic Pain, Sapienza University. Clinical data were systematically collected through structured interviews. All participants underwent 3T MRI scanning, including high-resolution T1-weighted MPRAGE sequences. Cortical thickness analysis was conducted using the FreeSurfer software suite. Multiple comparisons were corrected using a cluster-wise Monte Carlo simulation approach, with a corrected p-value of ≤0.05 considered statistically significant.

Results: A total of 65 TN patients and 22 healthy controls were included. Compared to controls, TN patients exhibited significantly reduced cortical thickness in several key regions of the somatosensory network, notably in the primary somatosensory cortex contralateral to the side of pain.

Conclusion: High-resolution structural MRI can detect subtle morphological alterations in the somatosensory system of patients with TN, potentially providing objective evidence of central nervous system damage in this condition.