Anterior Subconjunctival Anesthesia for Manual Small Incision Cataract Surgery: A Randomized Controlled Trial

To compare the effectiveness of anterior subconjunctival anesthesia (ASCA) with sub-tenon's anesthesia (STA) for manual small incision cataract surgery (MSICS), regarding pain, akinesia, surgeon comfort, and complications.

This trial randomized 164 patients into two groups. Group 1 received ASCA, and Group 2 received STA. MSICS was performed on all patients. Any complications of anesthesia were noted before starting surgery. Patient ocular motility during surgery was scored between 0 and 4 based on the number of directions of gaze in which movement persisted. Following surgery, patients scored pain felt during surgery on a visual pain-score analog, and the surgeon graded for "discomfort" felt during surgery from 0 (Nil) to 4 (additional anesthesia needed).

Chemosis due to anesthesia and persistence of ocular motility in all four gaze directions were seen in all 82 patients of Group 1, but these did not prevent the surgeon from performing MSICS. Seventy-seven patients (94%) in Group 1 and 79 (96.4%) in Group 2 had no or mild pain during surgery. The surgeon had moderate-to-severe discomfort in 14 (17.2%) Group 1 patients and 3 (3.6%) Group 2 patients, most of whom had deep-set eyes or exhibited excessive eye movements. Two patients in Group 1 and one patient in Group 2 were converted to peribulbar block.

ASCA is a safe and effective alternative for performing MSICS. It does not induce akinesia but provides adequate anesthesia for the surgery in most patients, except those with deep-set eyes, especially if displaying increased anxiety.