Abstract PR286

Abstract

Background & Objectives: Postherpetic neuralgia (PHN) patients suffer debilitating chronic pain, hyperalgesia, allodynia as well as emotional disorders such as depression, anxiety and insomnia. Knowledge regarding abnormal brain activity in PHN patients is still needed. Understanding the brain activity of PHN patients may be useful for clinical strategies. To identify regional brain activity change in resting-state PHN patients as compared to healthy controls by using regional homogeneity (ReHo) and fractional aptitude of low-frequency fluctuation (fALFF) methods. Correlations between spontaneous pain intensity and ReHo or fALFF were analyzed too. Materials & Methods: ReHo, fALFF change was detected in 19 PHN patients and 35 healthy controls, and their correlations to PHN pain intensity was assessed in PHN group. Results: PHN patients exhibited significantly abnormal ReHo and fALFF intensity in several regions (see the image below), mainly in the brainstem, thalamus, limbic system, temporal lobe, prefrontal lobe and cerebellum compared with healthy controls. Correlation analysis showed that most of the ReHo values of the aforementioned brain regions correlated well with VAS values. But little correlation was found between fALFF and VAS.Conclusion: For PHN patients, the local brain activity abnormity was not restricted to pain matrix. Besides regions related to pain perception, areas in charge of affective processes, emotional activity and pain modulation also showed abnormal local brain activity in a resting state, which may suggest complicated supraspinal function and plasticity change in PHN patients. ReHo was more closely correlated with pain intensity of PHN patients than fALFF. This work indicates that besides physical and emotional pain perception, mood disorder and pain modulation as reflections for PHN patients, and supports the potential use of therapeutic interventions that not only restrict to pain alleviation, but also attempt to ameliorate the cognitive and emotional comorbidities. Disclosure of Interest: None declared