Augmented Reality (AR) in Ophthalmology

What Is Augmented Reality?

Augmented reality (AR) is a technology that integrates computer-generated information with the user's environment in real time. In contrast to virtual reality (VR), which creates entirely artificial environments for the user, AR overlays perceptual information onto the real-world environment that users can experience. The main benefit of AR is that it helps to blend digital and three-dimensional components with a user's perception of the real world.

AR is not strictly restricted to the visual sense; various other feelings can also be implicated, including smelling, hearing, and touching. AR is used to change the natural environment visually or provide users with more information. As a developing technology, it is of great interest to researchers from different fields and has various uses, from entertainment to healthcare.

AR has been certified successful in medical education and training, navigation, and surgery in the healthcare sector. Moreover, ophthalmology connects closely with AR, as AR systems are generally based on vision produced by the eyes. So, AR has multiple applications in ophthalmology, like providing alternative or adjuvant choices in convenient and nonsurgical ways to benefit patients who could not receive surgical treatment. AR also has a vital role in education and clinical assistance in ophthalmology.

What Are the Applications of Augmented Reality in Ophthalmology?

Augmented reality can be applied to various visual field defects, such as color vision deficiency, blindness, nyctalopia (inability to see at night or in dim light), low vision, metamorphopsia (vision disorder causing shape of objects appears distorted), and amblyopia (reduced vision in one eye).

1) Visual Field Defects - Visual field defects (VFD) can be caused by various ophthalmic diseases, including glaucoma, retinitis pigmentosa, and stroke. This can lead to various problems in patients' daily lives, such as crossing the road, driving, reading, and visual searching. Fortunately, AR provides a considerable solution with improved searching capability and visual aids.

Techniques like overlaid windows, image remapping, danger indicators, and visual multiplexing have been developed to provide a visual aid. Specialized digital glasses are designed to adjust images based on a person's visual field measurements. Another method overlays a window showing a captured scene onto a user’s vision. However, they have the disadvantage of blocking the natural view. Visual multiplexing is a technique where multiple signals are transmitted on one channel to give complete information; this is helpful for people with tunnel vision by overlaying edge pictures onto their natural vision. AR systems can also track moving objects to alert people with limited vision to potential dangers.

2) Color Vision Deficiency - Color vision deficiency is an ophthalmic disease that affects many people globally. In this condition, individuals have difficulties perceiving and distinguishing specific colors. This condition can cause issues with daily activities and restrict their occupations. To date, medical treatment cannot cure CVD; however, AR systems can help users improve their ability to differentiate colors. Several AR devices, like Omnicolor and Chroma, are used for color vision deficiency (CVD) research. The processing technologies can be divided into two categories: augmenting visual information and substituting colors. Color substitution methods change colors so that people with CVD can easily distinguish the color. Another technique highlights target colors by replacing them with easier-to-see colors.

3) Blindness - Age-related diseases are considered the main cause of blindness. There is no treatment to reverse it, as it damages the pathway where visual data is transmitted from the eye to the brain. Blindness can be a big obstacle to the affected individual's life as it restricts mobility. Several augmented reality systems have been created to help people with vision impairments, which use light perception, color perception, and hearing to convey information. For those who can perceive color, some devices use colors to indicate distance, while others use the brightness of light-emitting diodes (LEDs). For those with complete blindness, a certain sound is used, with the intensity increasing as the distance shortens.

4) Low Vision - Low-vision individuals face difficulties in daily activities such as reading. The AR application in low vision helps focus on strengthening the capability to recognize in different strategies, including edge enhancement, contrast enhancement, text extraction, magnification, and object recognition. Magnification is the most common strategy for assisting people with low vision. In this method, images are enlarged and displayed in a window or over the user's sight.

However, it has drawbacks, such as reducing the field of view. Some research adjusts the magnified images' transparency so users can see the real environment and the magnified images together. Recent advancements in artificial intelligence, especially convolutional neural networks, have improved image recognition. Facial or object recognition and text extraction technologies have been conjugated with augmented reality to enhance user's recognition abilities.

What Are the Benefits of Augmented Reality (AR) in Ophthalmology?

• AR technology provides ophthalmologists with better visualization of ocular structures and abnormalities of complex conditions, such as retinal diseases or corneal abnormalities, to make accurate diagnoses and provide better treatment.

• It educates future ophthalmologists by simulating surgical procedures and allowing students to study in a risk-free environment.

• AR technology can inform patients about their eye conditions and treatment options.

• AR enables surgeons to improve surgical outcomes and reduce the risk of complications by planning and performing surgical procedures with greater precision.

What Are the Complications of Augmented Reality in Ophthalmology?

• Incorporating AR systems seamlessly with existing surgical workflows is a complex endeavor that remains a significant challenge for developers.

• The high cost of AR hardware and software solutions may pose a barrier to their adoption, particularly in resource-constrained healthcare settings.

• Specialized surgeons and operating room personnel training may be required to integrate ART into ophthalmic surgery.

• Implicating AR technology into medical devices for surgical uses requires getting clearance from regulatory agencies such as the FDA (Food and Drug Administration) and compliance with strict safety standards.

Conclusion

Augmented reality in ophthalmology is a great innovation in the field of ophthalmology, as it has multiple applications, from patient education to surgery. It empowers surgeons with enhanced visualization for treatment and diagnosis, real-time guidance, and improved decision support. However, certain challenges in implicating this technology still need to be addressed, such as the high cost, getting clearance from regulatory agencies, and others. As the field continues to mature, this technology will redefine the standards of safety, precision, and patient outcomes in ophthalmic surgery.