A Comparison of Squint Tests
Research type
Research Study
Full title
A comparison of the traditional Hess chart, a projector-based Lancaster test, and VR headset-based Lancaster test in the assessment of ocular deviation
IRAS ID
209165
Contact name
Peter Thomas
Contact email
Sponsor organisation
Cambridge University Hospitals NHS Foundation Trust
Duration of Study in the UK
0 years, 4 months, 1 days
Research summary
Strabismus, or squint, describes any misalignment of the eyes, and can affect both children and adults. As a result, the images of the outside world conveyed to the brain from the two eyes do not correspond, which can result in diplopia, or ‘double vision’. As well as impacting on a patient’s functionality, strabismus can have cosmetic and psychosocial ramifications. Furthermore, if left untreated in childhood, strabismus can lead to life-long visual impairment, despite best spectacle correction.
Current treatment is guided by the exact nature of the strabismus and the patient’s age; options include spectacle prescription to correct underlying refractive error, use of prisms to control deviation, or in certain cases, surgery. In order to investigate the type of strabismus present, and determine the best management, tests of ocular deviation are performed in Eye Clinics.
The aim of these tests is to ‘dissociate’ the eyes, and thus establish how each eye is working individually. The Hess chart and the Lancaster red-green test are two well-established tests of ocular deviation in clinical practice, which use red-green goggles to dissociate the eyes, and change the image that each eye receives. They are able to produce reproducible, pictorial representations of deviations of the eye to aid in management of strabismus.
However, both of these tests require a screen to be mounted onto the wall, upon which lights are projected, and the patient to be sat at the appropriate distance from the screen without moving their head for the duration of the test. In this study, we investigate whether a virtual reality headset-based Lancaster red-green test can produce comparable measurements of ocular deviation to the traditional Hess chart and Lancaster red-green test, without the need for a screen or projector, or control of head posture.
REC name
Yorkshire & The Humber - Leeds West Research Ethics Committee
REC reference
16/YH/0378
Date of REC Opinion
1 Sep 2016
REC opinion
Favourable Opinion