Guang Yang,1,* Qingyu Li,2,3,* Meiwen Tian,4,* Meimei Liu,4 Tinghui Zhang,4 Wenjun Guo,4 Qiang Li1 

1School of Microelectronics, Tianjin University, Tianjin, 300072, People’s Republic of China; 2Department of Cataract, Tianjin Eye Hospital, Tianjin, 300020, People’s Republic of China; 3Tianjin Key Lab of Ophthalmology and Visual Science, Tianjin, 300020, People’s Republic of China; 4Shenzhen Eye Hospital, Shenzhen Eye Medical Center, Southern Medical University, Shenzhen, 518040, People’s Republic of China

*These authors contributed equally to this work

Correspondence: Qiang Li, School of Microelectronics, Tianjin University, Tianjin, 300072, People’s Republic of China, Tel +8613820512683, Email liqiang@tju.edu.cn Wenjun Guo, Shenzhen Eye Hospital, Shenzhen Eye Medical Center, Southern Medical University, Shenzhen, 518040, People’s Republic of China, Tel +8613697406246, Email 402385889@qq.com

Purpose: Pterygium surgery is a common ophthalmological procedure, where effective management of postoperative pain is essential for ensuring patient satisfaction. This study aimed to investigate the risk factors for postoperative pain among Chinese patients undergoing pterygium excision surgery.
Patients and Methods: A total of 145 pterygium patients who underwent surgery from June 2020 to March 2021 at Shenzhen Eye Hospital were included. Anxiety levels were assessed using the Self-Rating Anxiety Scale before surgery, and pain levels were evaluated using the Numeric Rating Scale at various postoperative time points. Generalized linear model analysis was conducted with postoperative time-weighted average pain scores as the dependent variable and various potential risk factors as independent variables. These included traditional factors such as smoking history, alcohol history, ocular surgery history, and anxiety score as well as novel parameters like pterygium neck width, single- or double-headed pterygium, surgical corneal wound area, pterygium onset or recurrence, operating surgeon, congestion, pterygium invasion into the cornea, duration, graft conjunctival area, and preoperative pain score. We introduced the Shapley Additive exPlanations method to elucidate the contribution of these variables to time-weighted average pain scores.
Results: Among the 145 patients, 96 reported postoperative pain. No statistically significant differences were observed in baseline characteristics—such as age, sex, history of systemic diseases, smoking, alcohol use, and prior eye surgeries—between patients who experienced postoperative pain and those who did not. Anxiety scores, surgeon, pterygium neck widths, and preoperative pain scores were found to be significant risk factors for pain scores (p < 0.05).
Conclusion: Preoperative anxiety scores were positively correlated with pain scores. Significant differences in postoperative pain scores were observed among patients who underwent operations by different surgeons. Patients with wider pterygium neck widths experienced more severe postoperative pain. Higher preoperative pain scores were associated with more severe postoperative pain.

Keywords: pain management, preoperative anxiety, preoperative pain score