Chloroprocaine 3% Gel as a Novel Ocular Topical Anesthetic: Results from a Multicenter, Randomized Clinical Trial in Patients Undergoing Cataract Surgery.

Purpose: To compare the efficacy and safety of a novel ophthalmic anesthetic, chloroprocaine 3% gel to tetracaine 0.5% eye drops in patients undergoing cataract surgery with phacoemulsification. Methods: This was a prospective, randomized, multicenter, active-controlled, masked-observer, parallel group competitive equivalence study. The study comprised 338 patients having routine cataract extraction by clear corneal phacoemulsification, randomized to receive 3 drops of chloroprocaine gel (n = 166) or tetracaine eye drops (n = 172) before surgery. The primary objective of the study was to assess the equivalence of chloroprocaine gel to tetracaine eye drops as proportion of patients with successful ocular surface anesthesia, without any supplementation just before intraocular lens implantation. Safety measurements were pain, irritation, burning, stinging, photophobia, and foreign body sensation, graded by the patient and objective ocular signs. Results: Equivalence was demonstrated, with a somewhat higher success rate of chloroprocaine gel: 152/166 (92.0%) chloroprocaine versus 153/172 (90.5%) tetracaine patients achieved ocular surface anesthesia with no supplementation. Difference in proportions was 1.5% confidence interval [95% CI: (-3.6 to 6.6)] and 90% CI fell within (-10 to 10). Mean onset of anesthesia was 1.35 ± 0.87 min for chloroprocaine and 1.57 ± 1.85 for tetracaine (P = 0.083). Mean duration of anesthesia was 21.57 ± 12.26 min for chloroprocaine and 22.04 ± 12.58 for tetracaine (P = 0.574). No treatment emergent adverse events related to chloroprocaine were reported and no relevant findings related to local tolerance or vital signs were observed in both arms. Conclusions: Results obtained from the present cataract study demonstrated that chloroprocaine 3% ophthalmic gel is safe and effective, representing a valid alternative in ocular topical anesthesia. Clinical Trial Registration number: NCT04685538.

Patient and surgeon comfort in vitreoretinal surgery performed with Sub-Tenon's Anaesthesia.

Background. Since Stevens first introduced Sub-Tenon's anaesthesia into cataract surgery it has shown itself to be a safe, simple, and efficient technique. The advantages of this type of block are comparable to those of sharp needle anaesthesia and complications are minimal. Several studies have found that the anaesthesia provided by Sub-Tenon's capsule injection is as good as or better for cataract surgery than that achieved by retrobulbar injection, but the efficacy of Sub-Tenon's block in vitreoretinal surgery is less well established. Methods. We performed 50 vitreoretinal procedures; 50 eyes received a Sub-Tenon's injection of a 5 ml mixture (50:50) of lidocaine and ropivacaine, plus 15 IU mL-1 of Hyaluronidase. Results. In 45 cases, only one injection was needed to achieve sufficient anaesthesia and akinesia; in 5 cases a second injection was performed five minutes after the first. Mean surgical time was 45.7 minutes. After surgery, each patient was asked to indicate his value on the VAS pain scale. Mean VAS degree was 2.4. In 7 cases, VAS was > 3 and the pain was successfully managed with the administration of paracetamol in the postoperative period. No light perception was detected at the end of surgery in 33 patients. All cases with 2 injections had no light perception at the end of surgery. Anaesthesia lasted throughout the surgery in all cases. The surgeon performed all surgery comfortably and with no difficulty. Conclusions. According to our experience and to a growing body of evidence, Sub-Tenon's anaesthesia appears to be a safe, simple, versatile, and effective technique and should be considered as a real alternative method of anaesthesia in vitreoretinal surgery.

Retinal toxicity of intravitreal genistein in a rabbit model.

PURPOSE: The purpose of this study was to evaluate the preclinical safety of intravitreal genistein in rabbit eyes over a short-term period. METHODS: Twelve New Zealand albino rabbits were selected for this study. Four concentrations of genistein (LC Laboratories, Woburn, MA) were prepared: 24 mg/0.1 mL, 135 mg/0.1 mL, 270 mg/0.1 mL, and 540 mg/0.1 mL. Each concentration was injected intravitreally in one eye of three rabbits. As a control, the vehicle solution was injected into the other eye of each animal. Retinal safety of intravitreal genistein was studied with electroretinography and histologic examination in rabbits. Electroretinography recordings were made before the injection and 3 weeks after the injection. Eventually, the rabbits were killed and the retinas were examined by light microscopy. Immunohistochemical staining with caspase-3 and caspase-9 was also performed to evaluate apoptotic expression in all study and control eyes. RESULTS: Electroretinography studies showed no significant difference between control and genistein-injected eyes at any of the doses in the rabbit model. Histologic examination showed no retinal abnormality in the rabbits injected with different concentrations of genistein. Immunohistochemical staining with caspase-3 and caspase-9 showed no different apoptotic protein expression in any study or control eyes. CONCLUSION: Our results indicate that genistein is a safe intravitreal drug in the rabbit model up to 540 mg. If proven safe and efficacious in human studies, intravitreal injection of genistein could be considered a treatment alternative for ocular neovascularisation in selected cases.