Efficacy of Visual and Perceptual Training on Visual Function for Operative Congenital Ectopia Lentis Children

Sun Yat-sen University

Status: Not yet enrolling

Conditions: Ectopia Lentis; Lens Subluxation or Dislocation

Treatments: Device: perceptual learning visual treatment,HVT

Study type: Interventional

Funder types: Other

Identifiers

NCT07096622

2025KYPJ068

Details and patient eligibility

About

This is a single-centre, open-label, parallel-group randomized controlled trial with the following objectives: Firstly, the investigators aim to evaluate the efficacy of web-based visual and perceptual training therapy on visual function in children with postoperative congenital ectopia lentis. Secondly, the investigators target to investigate the proportion of patients achieving ≥2 lines improvement in best-corrected visual acuity (BCVA), changes in stereoacuity, quality of life scores, and treatment compliance following visual and perceptual training intervention. Thirdly, to explore the safety profile of visual and perceptual training therapy software in this specific patient population. Lastly, this study aims to provide evidence-based recommendations for visual rehabilitation training strategies in children with postoperative congenital ectopia lentis in the Chinese population.

Full description

Congenital ectopia lentis (CEL) is commonly observed in patients with Marfan syndrome. It is a rare genetic eye disorder caused by abnormal development of the lens zonules, leading to displacement of the lens from its normal anatomical position. In addition to abnormalities in the development of refractive media such as the cornea and lens, these patients may also exhibit abnormalities in the photoreceptive system, including the retina. Furthermore, since the patients receive abnormal visual input stimuli during the critical period of visual development, this often leads to the development of amblyopia in both eyes. Currently, for patients with severe visual impairment due to lens dislocation, the standard treatment involves lens extraction combined with primary intraocular lens implantation. However, for patients with bilateral amblyopia following CEL surgery, conventional treatment involves full-time refractive correction, which cannot prevent residual amblyopia. Additionally, patients who undergo extracapsular artificial lens implantation may experience astigmatism due to potential lens tilt post-surgery, which can impair visual function and mental health.

Visual perception training therapy (HVT) is an emerging treatment modality for amblyopia. Studies have shown that compared to traditional refractive correction and occlusion therapy, visual perception training therapy offers faster visual acuity improvement, higher compliance, and the ability to enhance binocular visual function. Furthermore, existing research indicates that for patients with anisometropia or small-angle strabismic amblyopia, the efficacy of visual perception training therapy combined with refractive correction is superior to refractive correction alone. As a form of visual perception training therapy software, web-based visual perception training therapy enables patients to complete training at home through game-based activities. It can also adjust training plans based on patients' conditions and training progress, offering personalized treatment plans to enhance treatment compliance and patient experience while enabling remote management by hospitals. The meridian perception learning module is particularly effective in improving uncorrected visual function for patients with astigmatism undergoing CEL surgery. However, to date, no studies have focused on the efficacy of visual perception training therapy in improving visual function for this specific population of CEL postoperative patients.

Enrollment: 82 estimated patients

Sex: All

Ages: 4 to 12 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Age 4-12 years, regardless of gender;
2. Previously diagnosed with congenital ectopia lentis;
3. History of bilateral lens extraction combined with intraocular lens suspension surgery, with the second eye surgery completed within 1 month ± 1 week;
4. Bilateral best-corrected visual acuity no less than 20/200 but below age-appropriate normal levels: for 4-year-old children, bilateral best-corrected visual acuity no better than 20/40; for children aged 5 years and above, bilateral best-corrected visual acuity no better than 20/30;
5. Written informed consent signed by both patients and parents/guardians.

Exclusion criteria

**Exclusion Criteria:**

1. History of ocular trauma or previous ocular surgery;
2. Unable to cooperate with treatment, examination, or follow-up assessments;
3. Concurrent lens dislocation recurrence, severe cataracts (dense, located on the visual axis, opacity diameter >3mm affecting central vision), secondary glaucoma, corneal endothelial decompensation, or retinal detachment requiring urgent surgical intervention;
4. Presence of diplopia in either eye;
5. Known history of neurological disorders (such as photosensitive epilepsy);
6. Post-operative participation in other clinical trials that may affect the results of this study;
7. Use of local/systemic medications that may cause visual impairment or other visual treatments (such as atropine eye drop suppression therapy, occlusion therapy, digital therapy, Bangerter filters, optical suppression, VR training, etc.) other than refractive correction within the past 3 months.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Single Blind

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82 participants in 2 patient groups

intervention group

Experimental group

Description:

Participants in the intervention group should undergo a re-examination at baseline and be fitted with appropriately prescribed glasses based on the examination results, which should be worn throughout the day; After receiving guidance from a trainer, participants will undergo treatment using the visual perception training therapy software (HVT, version number: V1.0.10000) on the online platform, for 30 minutes daily, over a total period of 3 months. Follow-up visits and eye examinations will be conducted at the 1st, 2nd, and 3rd months following the start of the trial.

Treatment:

Device: perceptual learning visual treatment,HVT

compare group

No Intervention group

Description:

Participants in the control group should undergo a re-examination at baseline, select glasses with appropriate prescriptions based on the examination results, wear them throughout the day, and continue for a total of 3 months. Follow-up visits and eye examinations will be conducted at 1, 2, and 3 months after the start of the trial.