The aim of our present study is to evaluate the efficacy of
pranoprofen eye drops as
pain relief during sequential second-eye
cataract surgery and to investigate the possible mechanism. Seventy-six patients scheduled for bilateral sequential
cataract surgery were randomly assigned to two groups: (1) treatment group (administered
pranoprofen eye drops), or (2) control group (administered
artificial tears). Preoperative anxiety and intraoperative
pain were assessed.
Monocyte chemoattractant protein 1 (MCP-1) in the aqueous humor was measured with a
suspension cytokine array. An extracapsular lens extraction model was established in the Wistar rat and the MCP-1 concentrations were measured with an
enzyme-linked
immunosorbent assay. We found that in the control group, the
pain scores were significantly higher during second-eye surgery than during first-eye surgery (both scores P < 0.001). In the treatment group, there was no significant difference in the
pain scores during first-eye and second-eye surgery (both scores P > 0.1). The
pain during second-eye surgery was significantly lower in the treatment group than in the control group (both scores P < 0.01). And in the 1-week and 6-week interval subgroups, the
pain scores during second-eye surgery were significantly lower in the treatment group than the control group (P = 0.047 and P = 0.035, respectively). While the second-eye MCP-1 level was significantly lower after a 1-week interval in the treatment group than in the control group (P = 0.012), but did not differ significantly after a 6-week interval (P > 0.1). A parallel trend in the MCP-1 concentration was detected in the rat model. In conclusion, the preoperative administration of
pranoprofen eye drops reduced the perceived
pain during second-eye
cataract surgery, especially when performed after 1-week and 6-week intervals between the first-eye and second-eye surgery. MCP-1, a
pain-related
cytokine, was associated with the
pain-relief mechanism of
pranoprofen when second-eye surgery was performed 1 week after second-eye surgery.