Evaluation of single stage adjustable strabismus surgery (SSASS) under topical anesthesia in patients with symptomatic diplopia

ABSTRACT

We wish to assess effectiveness of using topical anesthesia without sedation in single-stage adjustable strabismus surgery (SSASS). Sixteen consecutive adults with diplopia and those willing to undergo SSASS, participated in a prospective study between September 2018–August 2019. They underwent detailed ophthalmic evaluation, ocular alignment measurement by prism cover test (PCT), and sensory evaluation. Subsequently they underwent SSASS under topical anesthesia (2% lidocaine gel). Surgery was performed using conventional technique; ocular alignment was then reassessed in sitting position by alternate cover test using prisms, for which with Snellen’s chart was used as distance target and Lang’s fixation stick as near target. Absence of diplopia was considered the end point of measurement. Any adjustment, if required, was performed intraoperatively, after recleaning the operative area with povidone iodine and redraping the eye. Participants were reassessed 1 day, 1 month, and 3-month after procedure, ocular deviation, and presence or absence of diplopia was documented. Fifteen males and one female patient participated in the study. Mean age of the study population was 31.29 years (range 19–65 years). Of these, 62.5% of patients required intraoperative modification of planned surgical dose. Patients with esotropia, vertical deviations, and combined deviations obtained surgical success, which remained stable till 3-month review. Patients with exotropia had initial surgical success rates of 100% immediately following surgery (day 1 postoperative evaluation), but it decreased to 83.33% and 66.67% during one and 3-months follow-up visits. In this study all patients tolerated the procedure well, without systemic adverse occurrence, including vasovagal reflex and without the need for additional anesthesia. SSASS is a good option in patients with diplopia and variable ocular deviations. Topical anesthesia allows intraoperative adjustment of surgical dosing, with aim of orthophoria or relief from diplopia, leading to satisfactory results. Postoperative drift may occur in exotropia. Case selection and preoperative counseling are necessary for cooperation during surgery, under topical anesthesia.

KEYWORDS:

• Anesthesia
• techniques/ procedures
• adult strabismus