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The Study of Perceptual Eye Position Examination and Visual Perceptual Training in Postoperative Intermittent
Fan Tan1,2, Xubo Yang1, Hang Chu3
1Department of Ophthalmology, West China Hospital, Sichuan University, Chengdu, China.
Insights
Perceptual eye position (PEP) abnormalities persist after intermittent exotropia surgery. Dichoptic visual perceptual training effectively improved PEP, suggesting it can restore binocular vision.
Area of Science:
- Ophthalmology
- Neuroscience
- Vision Science
Background:
- Intermittent exotropia (X(T)) is a common strabismus condition.
- Postoperative management often aims to restore binocular visual function.
- Perceptual eye position (PEP) is a potential indicator of visual function.
Purpose of the Study:
- To investigate perceptual eye position (PEP) in children with intermittent exotropia (X(T)).
- To evaluate the efficacy of dichoptic visual perceptual training in improving PEP and binocular function post-surgery.
Main Methods:
- 30 non-strabismus children (control) and 54 postoperative X(T) children were enrolled.
- PEP was measured in all subjects.
- The X(T) training group (33 patients) underwent 3-month virtual reality-based dichoptic visual perceptual training.
- A non-training group (21 patients) served as a comparison.
Main Results:
- Children with postoperative X(T) exhibited abnormal PEP even with normal eye alignment.
- Dichoptic visual perceptual training significantly reduced PEP abnormalities in the training group.
- PEP measurements correlated with fixation disparity and overall binocular visual function.
Conclusions:
- Perceptual eye position (PEP) serves as a precise tool for assessing fixation disparity and binocular function.
- Dichoptic visual perceptual training shows promise in rehabilitating binocular visual function after intermittent exotropia surgery.
Abstract:
The aim of this study was to investigate perceptual eye position (PEP) and to evaluate the effect of dichoptic visual perceptual training in postoperative intermittent exotropia [X(T)]. We enrolled 30 non-strabismus children (control group) and 54 postoperative X(T) children [divided into training group (33 patients) and non-training group (21 patients)]. All subjects received measurements of PEP, and the postoperative X(T) children were measured both in the third postoperative day and the third postoperative month. All patients in training group received 3-month dichoptic visual perceptual training based on a unique virtual reality platform. The results showed that the postoperative X(T) children with normal eye position still had an abnormal PEP. After a period of visual perceptual training, the PEP pixels in postoperative children dramatically decreased. The results revealed that PEP could evaluate fixation disparity and binocular visual function perceptively and precisely, and the dichoptic visual perceptive training may rebuild binocular visual function.
