DEC 14, 2017
Pediatric Ophth/Strabismus
This cross-sectional study examines the utility of strabismus goggles, which feature a head-fixed laser target display and liquid crystal display shutters, for binocular dissociation.
Study design
Researchers compared ocular alignment measurements derived using the strabismus goggles with those derived using the standard tool, the Hess screen test. They studied 58 individuals aged 6 to 81 years, including 41 participants with congenital/acquired paralytic strabismus or concomitant strabismus and 17 healthy controls. Each participant underwent tests of visual acuity and ocular deviation mapping in 9 gaze positions.
Outcomes
The analysis revealed close agreement between measurements of horizontal and vertical deviation obtained from the strabismus video googles and the Hess screen. Strabismus googles additionally measured deviations in concomitant strabismus and visual suppression.
Total recording time was about 2 minutes, and the device was simple to use and easily incorporated into a clinical setting without any special screens.
Limitations
The goggles are designed for an average head size and did not fit all patients. Furthermore, this prototype is not equipped to correct for refractive errors. The LCD shutters did not completely block vision at an acute angle of incidence in corner eye positions, and the occluded eye sometimes perceived a shadow image of the laser target. Future hardware modifications will hopefully overcome these minor technical shortcomings.
Clinical significance
This novel device offers automated measurements of ocular deviation in children as young as 6 years. The strabismus video goggles can also reliably be used in patients with visual suppression, for whom conventional Hess screen testing is not possible. This could possibly lead to improved surgical strategies for concomitant or incomitant strabismus. I believe these novel goggles are a valuable addition to the existing strabismus armamentarium.