Surgical and sensory outcomes in patients with intermittent exotropia according to preoperative refractive error

The effects of refractive status on the outcomes of strabismus surgery in patients with esotropia

BACKGROUND

The success of the strabismus surgery can hinge on several factors. One of these factors is refractive condition like hyperopia or myopia. Our study seeks to evaluate the surgical outcomes in patients with esotropia and myopia.

METHODS

This case-control study encompassed all surgical cases of esotropia at Torfe and Negah Hospital between 2016 and 2021, which satisfied our specified inclusion criteria. The initial variables from electronic medical records were collected, including demographic, clinical, and surgery-related factors. At the final follow-up appointment, the level of eye deviation, both at distance and near, was recorded. We considered the operation a "success" for patients with a post-surgery distance eye deviation of 10(Pd) or less. Patients with greater deviation were classified as surgery failure. Statistical analyses were executed using SPSS software (version 16.0), and a P-value less than 0.05 was considered significant.

RESULTS

Of the 194 patients evaluated, 112 were incorporated into the study. Surgical failure was observed in 14.29% of myopic patients, 29.79% of hyperopic patients, and 31.82% of emmetropic patients. The myopia group displayed a 0.19 odd ratio for surgical failure compared to the combined hyperopia and emmetropia groups, not statistically significant (OR: 0.19, CI 95%: 0.03-1.02). Additionally, patients diagnosed with Lateral Rectus Under-action were found to be 6.85 times more likely to experience surgery failure(OR: 6.85, CI 95%: 1.52-30.94). An elevated risk of surgical failure was also identified in patients who underwent Inferior Oblique Weakening procedure, indicated by a 3.77-fold increase in the odds ratio for failure(OR: 3.77, CI 95%: 1.08-13.17).

CONCLUSION

In our study, despite numerical disparities, there was no statistical difference among the success rates of all esotropia patients with different refractive errors. The patients with LRUA or IOOA showed lower success rates. Myopic patients had higher post-op overcorrection with lower reoperation rates compared to hyperopic or emmetropic patients.

Impact of Online Video Game-Based Dichoptic Training on Binocular Vision Rehabilitation in Post-surgical Patients with Intermittent Exotropia

INTRODUCTION

Dichoptic training has emerged as a promising rehabilitation approach for improving binocular visual function in patients with strabismus. A prospective observational study design was employed to assess the effectiveness of online video game-based dichoptic training in rehabilitating binocular visual function in patients who had undergone an operation for intermittent exotropia.

METHODS

A total of 64 patients who had undergone an operation for intermittent exotropia were recruited and divided into the training group and the control group based on whether they would receive the dichoptic training. The dichoptic training was conducted for 3 months in the training group and the control group would not accept any form of orthoptic therapy. Assessments of binocular visual functions and deviation were conducted at baseline, 3-month and 6-month follow-up.

RESULTS

Twenty-nine participants in the training group (mean 9.69 ± 2.66 years old) and 26 participants in the control group (mean 8.41 ± 2.64 years old) completed follow-up. At both 3- and 6-month follow-ups, the training group showed superior distance stereopsis compared to the control group, with near stereopsis only showing significant difference at the 6-month follow-up. Additionally, the training group exhibited significantly less distance exo-deviation drift than the control group at these times, and no significant difference was observed in near exo-deviation drift between the groups. The control group had a significantly higher rate of suboptimal surgical outcomes at both the 3- and 6-month follow-up. However, no significant differences were observed in simultaneous perception and fusion functions between the two groups.

CONCLUSIONS

Online video game-based dichoptic training has the potential to become a novel postoperative rehabilitation strategy for patients with intermittent exotropia.

Preliminary Study of Short-Term Visual Perceptual Training Based on Virtual Reality and Augmented Reality in Postoperative Strabismic Patients

The study aimed to explore the potential effect of short-term visual perceptual training based on virtual reality (VR) and augmented reality (AR) platforms in postoperative strabismic patients. We enrolled 236 postoperative strabismic patients, among whom 111 patients received VR-based training, and 125 patients received AR-based training. The stereoacuity of 1.5 m and dynamic stereopsis were improved by VR training; meanwhile, AR training exhibited more improvement in stereoacuity of 0.8 and 1.5 m, dynamic and coarse stereopsis. It was suggested that the visual perceptual training based on VR and AR technology can be potentially applied in postoperative strabismus treatment to promote the recovery of binocular vision.

Short-Term Near Stereoacuity Improvements Following Favorable Surgical Alignment in Exotropic and Esotropic Patients

PURPOSE

Surgical treatment for strabismus is to promote binocular vision, and the study is to evaluate the effect of surgical realignment on near stereopsis in exotropic and esotropic patients.

METHODS

The records of patients who underwent strabismus surgery were retrospectively reviewed. Visual acuity, ocular deviations, fusion control, ocular motility, strabismus subtype and duration, surgery procedures, and stereopsis at before and at one month after surgery were collected. RMANOVA was performed to analyze stereopsis improvement by surgery. A logistic analysis was used to investigate the factors for stereopsis improvement.

RESULTS

143 exotropic and 40 esotropic patients were enrolled. The stereopsis was not significantly improved in patients with exotropia (p > .05), but not in esotropic patients (p < .01). Small degree of near deviation (β = 0.01), without vertical surgery (β = 0.11), and the high pre-surgery Titmus (β = -0.44) were related factors for stereopsis improvement in exotropia patients; male (β = 0.21) and the high pre-surgery Titmus (β = -0.36) were related factors for stereopsis improvement in esotropia patients.

CONCLUSION

The loss of stereopsis was significantly restored by surgery in esotropia patients and the extent of stereopsis recovery by surgery depends on the deviation at near distance, vertical surgery, and pre-surgery stereopsis in exotropes and on sex and pre-surgery Titmus in esotropes.