Comparison between single-injection inferomedial and inferotemporal peribulbar blockades before cataract surgery.

Purpose: To compare the efficacy and safety of single-injection inferomedial (IM) and conventional inferotemporal (IT) peribulbar blockades.

Patients And Methods: This prospective randomized study included 200 patients who were randomly allocated into two equal groups (n = 100 patients); in the first group, patients received IM peribulbar injection (IM group), while IT peribulbar injection was performed for the second group (IT group). The measurement data were patient characteristics, number of patients who required supplementations, total anesthetic volume injected, surgeon's experience and any recordable complications.

Results: The number of patients who required supplemental anesthetics due to inadequate block was significantly higher in the IT group (15 patients, 15%, vs. no patients, 0%, in the IM group). The total anesthetic volume injected was significantly lower in the IM group (5.6 ± 0.8 vs. 9.8 ± 0.7 ml in the IT group). Surgeon's satisfaction was significantly higher in the IM group (100 vs. 22% in the IT group). The incidences of complications were not significantly different between the two groups.

Conclusion: It is safe and effective to conduct single-injection IM peribulbar blockade using a small needle size and low anesthetic volume.