The Retina as a Biomarker for Parkinson's Disease: A Systematic Review
The Retina as a Biomarker for Parkinson's Disease: A Systematic Review
Neuro-Ophthalmology
The Retina as a Biomarker for Parkinson's Disease: A Systematic Review Sze Wai Rosa Li Da, Abigail Gardner, and Marcela Votruba
Introduction
Introduction
Parkinson's disease is the second most common neurodegenerative condition, affecting one percent of the global population over sixty years old and approximately one hundred fifty-three thousand people in the United Kingdom. It is due to the dysfunction and eventual death of dopaminergic neurons in the substantia nigra, resulting in a variety of impairments, including muscle movement and walking, stiffness, tremors, impaired balance alongside difficulties with speech, loss of smell, sleep, visual hallucinations, cognitive impairment and other basic tasks as the disease progresses.
Alongside these symptoms, patients with Parkinson's disease may experience a range of visual impairments, including contrast sensitivity, difficulty with reading, double vision, and spatial awareness. Dry eye disease, affecting sixty percent of patients, is also common, alongside a reduced blink rate, ptosis and Meibomian gland dysfunction.