Abnormal Regional Brain Functional Activity and Brain Network Connectivity in Primary Trigeminal Neuralgia Patients:...

Area of Science:

• Neuroscience
• Medical Imaging
• Neurology

Background:

• Primary trigeminal neuralgia (PTN) is a debilitating condition characterized by facial pain.
• Understanding the central nervous system mechanisms underlying PTN is crucial for developing effective treatments.

Purpose of the Study:

• To systematically identify core regions of altered brain activity and functional connectivity in PTN using resting-state functional magnetic resonance imaging (rs-fMRI).
• To integrate findings from multiple rs-fMRI metrics to provide a comprehensive understanding of PTN pathophysiology.

Main Methods:

• A systematic literature search was conducted across PubMed, Web of Science, and EMBASE for rs-fMRI studies comparing PTN patients with healthy controls.
• Activation Likelihood Estimation (ALE) meta-analyses were performed for Amplitude of Low-Frequency Fluctuation (ALFF/fALFF), Regional Homogeneity (ReHo), and Degree Centrality (DC).
• Seed-based functional connectivity analyses were also included.

Main Results:

• ALE analysis revealed distinct spatial patterns for different metrics, with limited overlap.
• Hypoactivity was consistently found in the left medial prefrontal cortex (ALFF/fALFF).
• Hyperactivity was observed in the posterior cerebellar lobe and temporal pole (ReHo and DC).
• Seed-based connectivity analyses showed no convergent findings, and limbic system activation was heterogeneous.

Conclusions:

• PTN involves complex, multidimensional brain remodeling rather than a single pain center dysfunction.
• Different rs-fMRI metrics offer complementary insights into PTN pathophysiology.
• Findings support targeted interventions and emphasize the need for differentiating neurophysiological metrics and clinical subtypes in future research.