Evaluation of small-volume (3 ml) ophthalmic anaesthesia for both subtenon anaesthesia using blunt-tipped curved needle and single medial canthal injection with sharp needle for phacoemulsification surgery

Abstract

Introduction Medial canthus injection as well as subtenon anaesthesia has been used in anterior segment surgery. In this research, we compared the effectiveness and safety of small volume (3 ml) for either technique. Patients and methods Forty eyes of 40 patients undergoing phacoemulsification surgery at the Research Institute of Ophthalmology, Giza, Egypt, were divided into two groups: group A (20 eyes) included eyes of patients who received subtenon injection with blunt-tipped curved needle and group B (20 eyes) included eyes of patients who received single injection at medial canthus with sharp needle. Following either injection, the akinesia score and surgeon and patient satisfaction scores were reported as well as any related complications. The studied data were subjected to statistical analysis and results emphasized. Results In our study, the akinesia score had a mean value of 6±2.43 for subtenon group and 3.25±2.61 for the single injection medial canthus group, with a highly significant difference (P 0.05). Conclusion For phacoemulsification, subtenon anaesthesia using small volume of 3 ml was more effective regarding better akinesia score compared with a similar volume of medial canthus injection, with lower rate of supplemental injection as well as better patient and comparable surgeon satisfaction. The main disadvantage was a higher rate of pain to injection as well as more need for facial supplementation.