Efficacy and Safety of HVT-Based Visual Function Training in the Treatment of Postoperative Undercorrection in Patients with Intermittent Exotropia

INTERVENTION: Control group:Pencil Push‐Up Training;intervention group:home‐based HVT(Home Visual Training) software training; CONDITION: Postoperative undercorrection of intermittent exotropia (IXT) PRIMARY OUTCOME: distance office control score;Stereoacuity; SECONDARY OUTCOME: Intermittent Exotropia Questionnaire, IXT‐QOL;Near office control score;Change in ocular deviation;Negative fusional vergence range, NFV;Adverse Event (AE) Recording;Near point of convergence, NPC;Positive fusional vergence range, PFV;Contrast sensitivity; INCLUSION CRITERIA: 1.Aged 6–18 years, regardless of sex; 2.Diagnosis of postoperative undercorrection, defined as an exodeviation of 10–25 prism diopters (?) at near or distance, measured using the prism alternate cover test while fixating on targets at 33 cm and 6 m; 3.Control ability: distance office control score of 1–5; 4.Postoperative interval: at least 2 months after surgery; 5.Preoperative diagnosis of basic‐type intermittent exotropia (IXT), with unilateral recession–resection surgery performed; 6.Uncorrected or corrected visual acuity of >= 0.8 in both eyes; 7.Voluntary participation in this clinical trial and provision of signed informed consent.