Dr. Sarika Gopalakrishnan, FAAO, PhD

Post-Doctoral Research Fellow, The Envision Research Institute, Wichita, KS, USA

Introduction to low vision:

Globally, there are about 285 million people who are visually impaired, of which 39 million are blind and 246 million have low vision. In India, 63 million people are visually impaired, of which 8 million are blind and 55 million people have low vision.⁽¹⁾ Low vision is the disability which is caused due to ocular conditions such as refractive errors, cataract, glaucoma, diabetic retinopathy, retinal detachment, macular degeneration, retinitis pigmentosa, albinism, retinopathy of prematurity, and Stargardt disease. ^(2,3) This leads to visual field defects such as peripheral field loss (PFL), central field loss (CFL), and overall blurred vision (OBV). In people with low vision, various visual functions will be affected; they might have difficulty in face recognition, reading, doing their day-to-day activities, education, work, and social life. Subjects with low vision experience difficulty in navigating through their surroundings.

Need for latest technology:

Patients with low vision are referred to low vision care clinic and are examined thoroughly to understand their visual difficulties. Clinically, there are numerous challenges which are not covered in the routine assessment of people with low vision. Functional vision assessment has multiple components, including visual field, near and distance vision, near and distance contrast, colour vision, and assessing difficulty in tasks of daily living. There are several difficulties in the assessment of functional vision in individuals with real-world tasks. ^(4-7)

What is Virtual reality?

Virtual Reality (VR) environments have enabled researchers to conduct experiments in a simulated real world, which may elicit responses from the subjects similar to those in real situations. ^(8-10) VR technology is the application of graphics systems in combination with a variety of display and interface devices to provide the effect of immersion in an interactive three-dimensional computer-generated environment, which is called a virtual environment. The VR technology can produce applications to assess patients, which provides a level of realism unattainable by other techniques. It helps in evaluating human performance in a realistic environment and gives us an insight of how an individual perceives the real world while he/she executes a task, and it also helps pick up difficulties which the individual might not be aware of. ⁽¹¹⁾

Development of virtual environment for assessment of visual performance:

A focus-group discussion (FGD) was conducted to gain a better insight of the problems which can be easily identified and isolated by interaction in a group setting. A bank setup was designed as a virtual environment using various software in Oculus Rift CV1 with Oculus Touch controllers. The visual tasks in the virtual environment aimed at assessing reading for distance, near and identification of objects against various contrast levels and different lighting levels. The VR performance score in normal individuals was 87 (IQR 4.6) and in low vision subjects was 60.85 (IQR 16.39), p<0.001.⁽¹²⁾

CONCLUSION

VR environments may represent useful approach for assessment of visual performance as emerging trends of technology. Various VR scenarios similar to real-world environments can be created and visual rehabilitation training can be provided to patients with low vision. Low vision rehabilitation with the latest assistive technology, apart from improving visual function, also has a positive influence on social functioning. The innovative assessment and intervention for the low vision population would help in improving the self-confidence of the individuals and provide motivation for independent living.

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Author:-

Dr. Sarika Gopalakrishnan is a Post-Doctoral Research Fellow with the Envision Research Institute, investigates different methods of providing augmented reality assistive technology for people who are visually impaired. In 2008, Sarika completed her Bachelor of Science degree in Optometry from the Elite School of Optometry, Sankara Nethralaya, in Tamil Nadu, India. She then joined Sankara Nethralaya as an Optometrist and initiated, as well as directed, a low vision care department for 14 years. She has initiated comprehensive rehabilitation services and multidisciplinary management of patients with visual impairment in Sankara Nethralaya. She has a teaching experience of 13 years and she was an assistant professor in Elite School of Optometry. She has organized a number of CME programs and workshops on ‘Low Vision Care’ all over India. She has trained optometrists from different parts of the world to initiate and practice Low vision care. She has received ‘Knight of the Blind’ award on Helen Keller Remembrance day in June 2011 from Lion’s Club International. She has been trained in evaluating the Functional vision assessment and she selects the Indian Blind Cricket team for World cup according to the World Blind Cricket Council (WBCC) criteria. She is  losely associated with policies of Optometry education and she is a member to prepare Indian Entry level Optometry Competency skill Standard (IELOCS). Sarika has many accolades, peer-reviewed publications and awards including being recognized as the first Indian woman to be honored as a Fellow of the American Academy of Optometry (FAAO) in the field of low vision in 2014. Sarika then became the first Indian female to pursue a PhD in the field of low vision care
investigating virtual and augmented reality assistive technology in head mounted displays.