Strabismus surgery under topical or general anesthesia: a comparative retrospective study

Purpose To assess the results of strabismus surgery under topical or general anesthesia and to evaluate demographic, medical, or surgical variables associated with clinical success. Methods Design: Comparative case series. Participants and Controls: Hospital and University based patient population concerning a total of 649 surgical procedures in 565 patients. Interventions: 451 (69.5%) squint corrections were conducted under topical anesthesia and 198 (30.5%) under general. Main Outcome Measure: residual angle of deviation 6 months after surgery, classified with a 4-point scale as: 'very good' (angle of deviation < 4 prism diopters (Δ)), 'good' (angle of deviation within 4 and 10 Δ), 'sufficient' (angle of deviation within 11 and 20 Δ), and 'insufficient' (angle of deviation > 20 Δ). Procedures classified in the 'very good' and 'good' groups reflected complete satisfaction for the clinical outcome, i.e., success of the procedure; while classifications of 'sufficient' and 'insufficient' indicated the surgeon's disappointment for the clinically obtained results, i.e., failure of the procedure. Chi-square test and multivariable logistic regression was applied for the analysis. Results Topical anesthesia was associated with satisfactory results in 372 (82.5%) procedures and general anesthesia in 127 (64.1%) (P<0.001). In patients with restrictive and paretic strabismus, satisfactory results were achieved in 44 (67.7%) and 85 (75.2%) of cases under topical anesthesia, respectively, and in 9 (32.1%) and 16 (53.3%) of cases under general anesthesia, respectively (P<0.001 and P<0.01). Statistically significant correlation with satisfactory results were related to the use of topical anesthesi (P<0.001), male gender (P=0.017), pre-operative potential stereopsis (P=0.002) and the surgical procedure of weakening (P=0.001). Conclusions This study demonstrates the advantages of topical anesthesia with non-adjustable sutures over general anesthesia in strabismus surgery, particularly in less predictable cases.