Amblyopia
Conditions
Keywords
Amblyopia, Visual impairment, New method for amblyopia screening, Pediatric amblyopia screening, Eye Tracking system
Brief summary
Amblyopia, characterized by reduced visual acuity, develops in childhood due to insufficient sensory stimulation of the affected eye. It is the leading cause of low vision and loss of stereoscopic vision in both children and adults. Currently, 99 million people worldwide are affected, with recent projections indicating 222 million by 2040. Amblyopia can result from anisometropia (70%), strabismus (30%), or the presence of an ocular pathology (1%). Early management of these conditions (before the age of 7) can prevent the onset of amblyopia. Therefore, screening for these conditions is a major public health challenge to reduce the prevalence and associated costs of visual impairment. The French-speaking Association of Strabology and Pediatric Ophthalmology (AFSOP) recommends systematic amblyopia screening for 3-year-old children. This screening involves measuring monocular visual acuity in both eyes (LEA chart at 3 meters), checking for strabismus (cover/uncover test), and performing a stereoscopic vision test (e.g., Lang I test). Amblyopia is currently underdiagnosed for two main reasons: 1) it is often asymptomatic (75% of cases) and therefore cannot be detected without systematic screening; and 2) there is significant difficulty in accessing medical care in certain regions, and thus access to professionals capable of performing this screening (doctors, orthoptists). The difficulty in accessing healthcare professionals capable of screening for amblyopia in children aged 3 to 7 has already been raised. We believe it would be beneficial to have an alternative screening method that is equivalent to the AFSOP-recommended method and accessible in areas with limited healthcare professionals. An eye-tracking system implemented in a virtual reality (VR) headset has recently been developed for monitoring eye movements. This system has shown effectiveness in rehabilitating visual field impairments in patients with traumatic brain injury. The system allows for remote monitoring of rehabilitation sessions, and data can be downloaded and viewed remotely via Wi-Fi. The main objective of this study will be to estimate the sensitivity of the new VR-based eye-tracking screening method amblyopia screening method using an eye-tracking system implemented in a virtual reality headset compared to standard screening in children aged 3 to 7 years.
Interventions
DIAGNOSTIC_TESTStandard screening procedure for amblyopia
The standard examination for amblyopia screening consists of three steps: A monocular visual acuity assessment using optotypes from the LEA scale, presented from the simplest to the most complex in front of each eye via an alternating occlusion mask. A cover/uncover test, during which the child is required to fixate on an image A Lang I stereopsis test performed under binocular vision.
DIAGNOSTIC_TESTNew amblyopia screening method using a virtual reality headset.
The examination with the virtual reality headset consists of three main steps: A monocular visual acuity assessment using optotypes from the LEA scale, presented from the simplest to the most complex in front of each eye via an alternating occlusion mask. The eye-tracking system analyzes fixation and the visual response of the stimulated eye. A cover/uncover test, during which the child is required to fixate on an image projected inside the headset. Eye movements are tracked to detect any deviations or abnormalities in ocular coordination. A Lang I stereopsis test performed under binocular vision, in which the child must identify three-dimensional images hidden within a virtual board. The eye-tracking system detects fixation on the images and allows evaluation of depth perception
Sponsors
University Hospital, Strasbourg, France
Study design
Observational model
CASE_CONTROL
Time perspective
CROSS_SECTIONAL
Eligibility
Sex/Gender
ALL
Age
3 Years to 7 Years
Healthy volunteers
Yes
Inclusion criteria
* Patients aged 3 to 7 years at the time of consent signing. * Patients followed in the Ophthalmology Department of Strasbourg University Hospital (CHU Strasbourg). * Holders of parental authority must be affiliated with or beneficiaries of the health insurance system. * Holders of parental authority must be capable of understanding the objectives and risks related to the research, and able to provide dated and signed informed consent. * Amblyopic patients must have amblyopia diagnosed by the reference screening method. * Non-amblyopic patients must have undergone routine screening confirming the absence of amblyopia or any other ocular condition that could lead to amblyopia. * Screening must be performed in the Ophthalmology Department of CHU Strasbourg, unless a prior screening has been performed according to established guidelines and fully documented in a report by the patient's ophthalmologist (detailed results of the three standard screening tests). * The screening examination must have been performed within the three months prior to the signing of the informed consent form.
Exclusion criteria
* Amblyopic children currently undergoing treatment or having previously received treatment for amblyopia (optical correction, strabismus surgery, occlusion therapy, orthoptic rehabilitation). * Children presenting conditions or states that may cause side effects related to the use of the virtual reality headset (epilepsy, neurological or developmental disorders, autism spectrum disorders, dizziness, nausea, claustrophobia, etc.). * Inability to provide informed information to the patient or holders of parental authority (emergency situations, difficulties in patient comprehension, etc.).
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Sensitivity of a new amblyopia screening method compared to standard screening | At enrollment. | Sensitivity of a new amblyopia screening method using an eye-tracking system implemented in a virtual reality headset, compared to standard screening, in children aged 3 to 7 years. Sensitivity = (true positives) / (false negatives + true positives) |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Sensitivity and specificity of the eye-tracking system compared to the same tests performed during standard screening | At enrollment. | These are respectively: Monocular visual acuity of both eyes measured using the LEA symbol scale at 3 meters, presented via the virtual reality interface. Presence or absence of a refixation movement during the cover/uncover test for strabismus screening. Presence or absence of stereoscopic vision anomalies evaluated by projecting a Lang I test under binocular vision within the virtual reality headset. |
| Cover/uncover test for strabismus screening : angle of deviation | At enrollment. | The angle of deviation of movement of each eye (refixation movement) will be recorded using a cover/uncover test combined with monocular stimulation |
| Proportion of adverse events recorded during the diagnostic process | Day of the diagnostic examination (Day 1) | The proportion of adverse events will be recorded by the investigator accompanying the child during the examination with the virtual reality system across all study groups. In particular, adverse events related to the use of the virtual reality headset will be documented (nausea, discomfort, photophobia, seizure). |
| Specificity of the eye-tracking system compared to standard screening | At enrollment. | Specificity of the eye-tracking system implemented in a virtual reality headset, compared to standard screening in children aged 3 to 7 years. Specificity = (true negatives) / (false positives + true negatives) |
| Cover/uncover test for strabismus screening : direction | At enrollment | The direction of movement of each eye will be recorded using a cover/uncover test combined with monocular stimulation |
| Cover/uncover test for strabismus screening : velocity | At enrollment | The velocity of movement of each eye (refixation movement) will be recorded using a cover/uncover test combined with monocular stimulation |
| Proportion of patients unable to complete the scheduled examination using the virtual reality headset | Day of the diagnostic examination (Day 1) | The proportion of patients unable to complete the scheduled examination using the virtual reality headset for any reason (including refusal to wear the headset, anxiety, or other factors) will be documented. This will include the number of patients for whom the examination could not be performed due to these reasons. |
Countries
France
Contacts
Primary ContactLéa DORMEGNY
Backup ContactLauriana SOLECKI
Outcome results
None listed