From the Guidelines
Parkinson's disease can cause significant vision changes, including blurred vision, double vision, dry eyes, difficulty with contrast sensitivity, and problems with eye movements, which can be managed with regular eye exams, lubricating eye drops, prism glasses, and proper lighting, as well as medication adjustments and physical and occupational therapy. These changes occur because Parkinson's affects the dopamine-producing cells that help control eye movements and visual processing. Patients may experience reduced blinking, which leads to dry eyes, and may have trouble with depth perception and tracking moving objects. Visual hallucinations can also occur, especially as the disease progresses or as a side effect of medications 1. According to a recent study published in Translational Neurodegeneration in 2022, visual hallucinations are a common symptom in dementia with Lewy bodies, occurring in up to 80% of patients, and can be assessed using various scales, including the Neuropsychiatric Inventory (NPI) and the Scale for the Assessment of Positive Symptoms for Parkinson’s Disease Psychosis (SAPS-PD) 1.
To manage vision changes in Parkinson's disease, the following strategies can be employed:
- Regular eye exams to monitor vision changes and adjust treatments as needed
- Lubricating eye drops to manage dry eyes
- Prism glasses to correct double vision
- Proper lighting to improve contrast sensitivity
- Medication adjustments to minimize visual hallucinations
- Physical and occupational therapy to develop strategies to compensate for visual challenges. A study published in the Journal of the American College of Radiology in 2020 highlights the importance of correct diagnosis of Parkinsonian syndromes, which can be challenging based on clinical features alone, and emphasizes the role of imaging as an essential diagnostic tool 1.
It is essential for patients to report any vision changes to their healthcare provider, as addressing these issues can significantly improve quality of life and reduce the risk of falls and accidents. By prioritizing the management of vision changes, patients with Parkinson's disease can maintain their independence and overall well-being.
From the Research
Vision Changes in Parkinson's Disease
- Patients with Parkinson's disease experience various visual disturbances, including changes in color vision and contrast sensitivity, as well as difficulties with complex visual tasks such as mental rotation and emotion recognition 2.
- Ocular impairments can affect different aspects of vision and eye movement, including dry eyes, blepharospasm, reduced blink rate, saccadic eye movement abnormalities, and impaired voluntary and reflexive eye movements 3.
- Visuoperceptive impairments can affect the ability to perceive and recognize visual stimuli accurately, including impaired contrast sensitivity, reduced visual acuity, color discrimination, and object recognition 3.
- Visuospatial impairments can also occur, including difficulties perceiving and interpreting spatial relationships between objects and judging distances or navigating through the environment 3.
Visual Dysfunction and Disease Progression
- Progressive visual dysfunction, macular thinning, and axonal loss can be detected in patients with Parkinson's disease 4.
- Changes in visual function parameters and retinal nerve fiber layer thickness are associated with disease progression 4.
- Analysis of the macular thickness and the retinal nerve fiber layer by spectral-domain optical coherence tomography (SD-OCT) can be useful for evaluating Parkinson's disease progression 4.
Management of Visual Dysfunction
- Visual system impairment in Parkinson's disease can range from subtle examination findings to severe disability 5.
- Potential treatments for visual dysfunction in Parkinson's disease include dopamine agonists, which can help reduce the incidence of motor complications and improve visual function 6.
- Early use of dopamine agonists may be beneficial in reducing the incidence of motor complications and improving visual function in patients with Parkinson's disease 6.