Jian Jiang,1,2,* Xiaoyan Hou,1,* Lili Gu,3 Xian Liu,1 Huiting Lv,1 Jiaxin Xiong,1 Hongmei Kuang,1,2 Xiaofeng Jiang,1 Shunda Hong1,2 

1Department of Radiology, The First Affiliated Hospital, Nanchang University, Nanchang, People’s Republic of China; 2Jiangxi Medical Imaging Research Institute, Nanchang, People’s Republic of China; 3Department of Pain, The First Affiliated Hospital, Nanchang University, Nanchang, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Shunda Hong, Department of Radiology, The First Affiliated Hospital, Nanchang University, 17 Yongwaizheng Street, Nanchang, Jiangxi, 330006, People’s Republic of China, Tel/Fax +86-791-88693825, Email dyfy05441@ncu.edu.cn

Purpose: This study aimed to explore the abnormal changes in short- and long-range functional connectivity density (FCD) in patients with herpes zoster (HZ) and postherpetic neuralgia (PHN).
Patients and Methods: Twenty HZ patients, 22 PHN patients, and 19 well-matched healthy controls (HCs) underwent resting-state functional magnetic resonance imaging scans. We used FCD mapping, a data-driven graph theory method, to investigate local and global functional connectivity patterns. Both short- and long-range FCD were calculated and compared among the PHN, HZ, and HC groups. Then, the abnormal regions were used to calculate seed-based functional connectivity. Finally, correlation analyses were performed between the altered FCD values and clinical datas.
Results: Compared with HCs, HZ patients showed significantly increased long-range FCD of the bilateral cerebellum, thalamus, parahippocampal gyrus, superior temporal gyrus and lingual gyrus. HZ patients also displayed significantly decreased short-range FCD of the bilateral posterior cingulate gyrus, median cingulate/paracingulate gyri, and left precuneus. Compared with HCs, PHN patients displayed significantly decreased long-range FCD of the bilateral superior frontal gyrus and decreased short-range FCD in the bilateral posterior cingulate gyrus, median cingulate/paracingulate gyri, and precuneus. However, there was no significant difference in either long-range or short-range FCD between the PHN and HZ patients. Long-range FCD deficit areas and the right insula showed altered functional connectivity in PHN patients. Furthermore, pain duration in patients with PHN was correlated with abnormal long-range FCD.
Conclusion: Herpes zoster pain widely affects intra- and inter-regional functional connectivity, leading to disrupted short-range FCD and increased long-range FCD during different stages of the disease. Long-term chronic pain in PHN patients may impair the pain emotion regulation pathway. These findings could improve our understanding of the pathophysiological mechanisms of HZ and PHN and offer neuroimaging markers for HZ and PHN.

Keywords: functional connectivity density, herpes zoster, postherpetic neuralgia, pain, functional magnetic resonance imaging