Sight and Sound Mind: Navigating Eye Health with Parkinson’s

Vision problems in Parkinson’s are often overlooked until they become undeniable. In a presentation for Parkinson's Community Los Angeles (PCLA) as part of their "Let's Talk Parkinson's" series, Dr Alexander M. Solomon, a neuro-ophthalmologist at Pacific Neuroscience Institute, tackled this subject head-on. During the webinar, titled "A Closer Look: Eye Issues in Parkinson’s", Dr Solomon explored the complex relationship between the eyes and the brain, offering a roadmap for distinguishing between normal ageing and the specific visual challenges presented by the condition. Vision is our dominant sense. It is the primary interface through which we interact with technology, navigate our homes, and connect with the world. Yet, for those living with Parkinson’s, the visual experience can often become complicated, not necessarily by blindness, but by a series of nuisances that impact quality of life. Dr Alexander Solomon, a neuro-ophthalmologist at the Pacific Neuroscience Institute, recently shed light on the intersection of the eyes and the brain, offering practical solutions for common frustrations. It is crucial to first distinguish between structural eye problems and neurological ones. A neuro-ophthalmologist does not just look at the eyeball; they investigate the complex cabling—the optic nerve—that connects the eye to the brain, as well as the brain regions responsible for processing that image. Just because one has Parkinson’s does not provide immunity from the standard wear and tear of ageing. Cataracts, glaucoma, and the need for reading glasses happen to everyone. However, Parkinson’s introduces specific challenges that require a tailored approach. The Dry Eye Paradox The most prevalent issue, by a significant margin, is dry eye. We blink to sweep a fresh coat of tears across the eye, keeping it moist and clear. In Parkinson’s, the automatic blink rate often slows down. Without that frequent windscreen wiper motion, the eye dries out. This leads to a gritty sensation, light sensitivity, and fatigue. Paradoxically, the most common symptom of dry eye is a watering eye. The body realises the eye is parched and panic-floods it with reflex tears, but because the baseline lubrication is poor, the eye continues to feel irritated. The solution lies in the pharmacy aisle, which Dr Solomon admits can be as overwhelming as buying toothpaste for the first time. The gold standard is preservative-free artificial tears. Unlike the 'get the red out' drops—which mask symptoms—these replenish moisture. Because they lack preservatives, they can be used as often as needed. A good tip for remembering them is to pair the drops with mealtimes or medication schedules. For those who find drops insufficient, the issue might be the oil glands in the eyelids, which stop the tears from evaporating. A warm compress—a clean flannel run under hot water and held over closed eyes for ten minutes—can melt the clogged oils, acting like a spa treatment for the eyelids. Seeing Double Double vision is another frequent complaint, affecting up to 30 per cent of people with Parkinson’s. It is vital to determine if the double vision is caused by the eye itself (often a cataract or severe dryness) or by the eyes being misaligned. If covering one eye makes the double image disappear, the eyes are simply pointing in different directions, much like two cameras failing to focus on the same subject. This misalignment often manifests as 'convergence insufficiency'. When we read or look at something close up, our eyes naturally cross slightly to focus. Parkinson’s can make this reflex sluggish. The words might swim or split on the page. While general eye exercises are typically ineffective, this specific reflex is the exception. 'Pencil push-ups'—bringing a target slowly towards the nose until it doubles and then retreating—can help retrain the eyes to work together. For more stubborn cases, prisms in glasses or corrective surgery can realign the world. The Reading Dilemma Reading is a cognitively demanding task requiring sharp focus and rapid eye movements. Many people rely on varifocals (progressives) or bifocals as they age. However, these lenses restrict the reading area to a small corridor at the bottom of the glass. For someone with Parkinson’s, whose eye movements might be less fluid, finding that 'sweet spot' can be exhausting. If reading has become a chore, it might not be the eyes failing, but the glasses. Switching to a dedicated pair of single-vision reading glasses provides a wide, generous field of view, removing the need to constantly adjust head position to find focus. Depth Perception and Freezing The brain constructs a 3D map of the world by comparing images from both eyes. When Parkinson’s affects contrast sensitivity or causes misalignment, depth perception flattens. This makes judging the height of a kerb or the distance to a parked car difficult. Poor visual cues can even contribute to freezing of gait, as the brain struggles to interpret the environment safely. Simple environmental hacks, such as bright lighting and high-contrast tape on stair edges, can help the brain navigate these spatial uncertainties. The Taboo of Hallucinations Perhaps the most sensitive topic is visual hallucinations. Seeing things that are not there—shadows in the periphery, or formed images of animals or people—occurs in roughly half of people with Parkinson’s, yet it is rarely discussed. It is essential to understand that this is not a sign of 'going crazy' or a loss of cognitive capacity; it is a direct manifestation of the condition or a side effect of medication. Vision acts as an anchor for reality. When external visual input is poor (due to low light or eye problems), the brain attempts to fill in the gaps with internal imagery, leading to hallucinations. Ensuring one’s glasses prescription is up to date and lighting is adequate can sometimes suppress these phantom images. If they become distressing, medication adjustments can help, but often simply knowing they are a benign symptom of Parkinson’s provides immense relief. A Note on Medications Finally, it is worth noting that treatments for Parkinson’s can occasionally impact the eyes. Amantadine, for instance, can sometimes cause corneal swelling, while anticholinergics may blur near vision. If vision changes drastically after a medication shift, it is worth consulting both a neurologist and an eye specialist. The overarching message is one of reassurance. While Parkinson’s affects the mechanics of sight, it rarely leads to blindness. Whether it is using a simple warm compress for dryness, getting a dedicated pair of reading glasses, or realigning double vision with prisms, most of these visual hurdles are treatable. The goal is to keep the world in focus, allowing life to be lived with clarity.