Purpose: The purpose of the study was to evaluate 2 agents used during retrobular injections to relieve pain in blind eyes.
Methods: This masked prospective randomized study compared retrobulbar injections for blind painful eyes that were divided into 2 groups: eyes in group 1 (G-I) received 1.5 mL of absolute alcohol (ethanol) and those in group 2 (G-II) received 1.5 mL of chlorpromazine (25 mg/mL). The pain was graded before, during, and after intervention using a verbal numeric visual analog scale. Intraocular pressure (IOP) and adverse events were also recorded. Complete success was defined as no pain after injection. Treatment failures were classified as further intervention (evisceration-enucleation) or no change in visual analog scale pain scores.
Results: Both groups included 16 patients each. Complete success was achieved in 7 of 16 (43.7%) patients in G-I and in 6 of 16 (37.5%) in G-II. The failure rate was 5 of 16 (31.3%) in G-I and 6 of 16 (37.5%) in G-II. Postoperative adverse events occurred in 33.3% of patients in G-I and 56% of patients in G-II. Transient eyelid edema was more prominent in G-II. Reduction in IOP occurred after injection in both groups. In G-I, IOP decreased from a mean of 24.3 to 14 mm Hg. In G-II, IOP decreased from 27 to 15 mm Hg. Five of the 7 (71.4%) patients with initial IOP>45 mm Hg suffered from severe pain. After injection, only 1 patient with an IOP>27 mm Hg had moderate pain.
Conclusions: Retrobulbar alcohol or chlorpromazine decreased IOP and reduced pain in approximately two-thirds of blind painful eyes with few postoperative complications. However, 33% of patients required further intervention to manage pain.