Virtual reality perimetry facilitates visual field evaluation in a previously non-assessable eye with severe glaucoma

Purpose: Virtual reality perimetry (VRP) is rapidly growing in popularity. Advantages of these devices have been noted in the literature: they require less capital investment than table-mounted perimeters, have a smaller footprint, and improve patient comfort. Unlike traditional perimeters, virtual reality perimeters can assess both eyes simultaneously, which it does by default on most of its testing algorithms. This novel function leads to an advantage of VRP over traditional perimetry that has not yet been reported: the ability to assess the visual field of an eye with poor fixation. We report a patient with advanced glaucoma who could not perform reliable standard perimetry due to a central scotoma in one eye but could perform VRP testing of each eye simultaneously. Observations: A 23-year-old male with advanced congenital glaucoma in the left eye presented for follow-up perimetry testing. In prior visits, his right eye consistently demonstrated a normal visual field, but left eye showed a progressively worsening global defect with poor reliability indices. At the present visit the patient performed VRP, which tested both eyes simultaneously. Good fixation with the right eye facilitated a reliable visual field of the left eye. Conclusions and importance: The virtual reality perimeters tests both eyes simultaneously, which traditional perimeters cannot do. In this case, fellow eye fixation facilitated the acquisition of a clinically meaningful visual field from a poorly fixing eye due to advanced glaucoma.