Exploring a Quantitative Formula for the Total Surgical Amount in Patients With Type III Acute Acquired Concomitant Esotropia.

Purpose: To establish a dose-response reference for surgical planning in type III acute acquired concomitant esotropia (AACE).

Methods: This study included consecutive patients who underwent unilateral or bilateral medial rectus recession for type III AACE or common forms of esotropia correction from January 2019 to August 2023. All patients with a minimum follow-up of 3 months were analyzed.

Results: A total of 269 participants were included in the study, with 170 having type III AACE and 99 having esotropia. The mean age of the participants was 20.93 ± 12.83 years, including 166 males and 103 females, with preoperative angles of deviation measuring 35.37 ±13.18 degrees. It was found that preoperative horizontal deviation had a significant impact on the total surgical amount required by the patients. When predicting the total surgical amount for patients with type III AACE, the recommended regression equation is Y = 3.259 + 0.174 × preoperative horizontal deviation. Additionally, for patients with type III AACE who had preoperative horizontal deviation less than 40 degrees, the quantified reference formula for the total surgical amount was Y = 1.746 + 0.236 × preoperative horizontal deviation. For patients with type III AACE who had preoperative horizontal deviation of 40 degrees or greater, the quantified reference formula for the total surgical amount was Y = 4.600 + 0.143 × preoperative horizontal deviation.

Conclusions: This study conducted a detailed quantitative analysis of the impact of preoperative horizontal deviation levels on the total surgical amount for patients with type III AACE and established specific quantitative reference formulas to inform surgeons' surgical planning.