Anterior Chamber Paracentesis Offers a Less Painful Experience During Intravitreal Anti-vascular Endothelial Growth Factor Administration: An Intraindividual Study

Introduction: In order to improve comfort and compliance to treatment of the patient during the intravitreal injections (IVIs), relieving pain may help and provide getting better results. The purpose of the study was to evaluate the efficacy of anterior chamber paracentesis on pain perception and the factors related to pain perception during intravitreal injection procedures. Material and methods: This prospective randomized study includes 212 eyes of 106 patients scheduled for bilateral IVI of ranibizumab 0.5 mg/0.05 cc under topical anesthesia. All patients underwent full ophthalmologic examination, including intraocular pressure (IOP), anterior chamber depth (ACD), and axial length (AL) measurements. Group 1 received IVI following anterior chamber paracentesis (ACP) and group 2 received IVI without ACP. Intraocular pressure was measured five minutes and 30 minutes after the procedure. Pain perception was assessed by visual analogue scale (VAS) grading from 0 to 10. Results: Mean VAS score for groups 1 and 2 was recorded as 0.51±1.00 and 1.32±1.50, respectively. Correlation analysis revealed a positive correlation between VAS score and history of previous IVI, preinjection IOP values, and an inverse correlation with the presence of reflux in both groups, in addition to inverse correlation with ACD in group 2. Conclusions: ACP may offer a comfortable, effective, and less painful alternative to prevent the acute rise in IOP after IVI, especially in patients with small anterior chambers, small vitreous volumes, with a history of multiple injections, and in patients with advanced glaucomatous optic neuropathy.