Research in Ophthalmology
Vision is arguably one of humanity’s most important senses. It is the only sensory modality with nationally and internationally recommended and (depending on the country) legislated thresholds of quality to permit activities such as driving (1–3), civil and military aviation (4), and heavy machinery operation (5). Located in the occipital lobe, the visual cortex in most humans contains approximately 15-20% of the 30 billion neurons that comprise both cerebral hemispheres (6). This is larger and more complex than our primate relatives (7) which is likely attributable to the range of needs that our vision serves, from functional acuity and spatial, motion and colour perception necessary for day to day tasks, to the numerous interactions between vision and thought, memory (and learning) and emotion, which has led to more research on vision and its interactions than on any other traditional sensory modality (8).
Consequently, the loss of vision can have devastating effects for individuals at all stages of life. Population-based surveys indicate that individuals rank the threat of vision impairment (usually termed “sight loss”) greater than the loss of other traditional senses such as hearing, touch and taste (9,10). It is estimated up to 340 million people worldwide live with some form of vision impairment (11), which is associated with increased risks of developmental delays in children (12,13), increased burdens of educational attainment in young-working age adults (14), and poorer indices of quality of life, mood, confidence and social interaction in all ages (15–17). In older adults who are at greatest risk of eye disease, vision impairment has been linked with increased risks of cognitive decline, loss of independence as well as increased risks of mortality (18–21). There is a significant financial and societal burden associated with vision impairment as well, compounded by the reduced earning potential of individuals with vision impairment which is disproportionately worse in less economically developed countries (22,23).
The field of ophthalmology seeks to understand, and stabilise, reverse, and/or prevent vision impairment, as well as promote awareness of eye disease in the general public. Eyes have complex interactions with many other body systems, and while ophthalmologists primarily treat and monitor eye-specific disorders such as age-related macular degeneration (AMD), glaucoma and cataracts, we are often called upon to assess individuals who have eye manifestations of other systemic diseases, such as diabetes, thyroid and rheumatological issues, and neurological disorders such as strokes, Parkinson’s disease and multiple sclerosis. Advances in medical imaging and therapeutics in the preceding few decades have revolutionised many aspects of ophthalmology – from the introduction of phacoemulsification techniques for cataract surgery in the 1960s, to the increasing availability of high resolution imaging such as optical coherence tomography (OCT) since the 1990s allowing microscopic visualisation and monitoring of eye disease (Figure 1), to the introduction of novel anti-vascular endothelial growth factor (anti-VEGF) drugs in the 2000s that finally offered a chance for patients with wet AMD to recover lost vision and prevent the progression of their disease.