Safety and efficacy of various topical anesthesia for intravitreal injection: a randomized controlled trial

This study aimed to determine the efficacy of various types of topical anesthesia prior intravitreal injection in an effort to lessen adverse effects such as pain and subconjunctival bleeding.

This randomized controlled study included 239 patients. All patients were randomly assigned to either receive: (1) Lidocaine gel 3% (Anaesthetic BL 3% gel), (2) Lidocaine gel 10% (Anaesthetic BL 10% gel), (3) Oxybuprocaine 0.4% eye drops (Localin), (4) Tetracaine HCl 1%, eye drops (Tetracaine) (5) A combined Oxybuprocaine 0.4% eye drops (Localin) and an ice patch. Patients' discomfort, itching, burning and pain (using Visual Analog Scale), and bleeding size (using images) were measured one and ten minutes post-injection. Tolerability was calculated by averaging patients' pain, discomfort, itching, and burning scores.

In the one- and ten-minute post-injection analyses, the groups receiving Tetracaine (0.60 ± 0.63, 0.50 ± 0.61) and the combined Oxybuprocaine and ice patch anesthesia (0.55 ± 0.66, 0.38 ± 0.58) had the lowest mean tolerability scores. In most parameters (discomfort burning, and pain scores) the Tetracaine and the combined Oxybuprocaine and ice patch anesthesia demonstrated the lowest mean scores. All subjective criteria assessed by the surgeon immediately following the injection were not found to be significantly different at any group, such as movements during injection (p = 0.19), complaints during injection (p = 0.56), complaints following injection (p = 0.21). Bleeding size (area or circumference) was not statistical different between groups.

This study demonstrated a considerable reduction in pain and overall tolerability with Tetracaine or a combination of ice patch and Oxybuprocaine anesthesia. These findings may lessen patients' discomfort and improve their tolerance.