Ophthalmologic manifestations of Parkinson disease

From EyeWiki
Original article contributed by: Grecia Rico
All contributors: Ayman Okla Suleiman, MD
Assigned editor: Andrew Go Lee, MD
Review: Assigned status Up to Date by Ayman Okla Suleiman, MD on September 14, 2015.


Ophthalmologic manifestations of Parkinson disease

Parkinson disease is a progressive neurodegenerative disorder characterized by multiple clinical features associated with decreased levels of dopamine.

Disease

Parkinson disease is a progressive and degenerative disease of the central nervous system presenting with a diverse variety of clinical features. Ophthalmologic manifestations of Parkinson disease can originate from a motor or a sensory dysfunction.

Pathophysiology

The decreased levels of dopamine in the central nervous system contribute to both motor and sensory symptoms. In the eye, dopamine is a neurotransmitter present in amacrine cells in the retina and it is thought to regulate the activity among ganglion cells, bipolar cells and photoreceptors.

Signs and Symptoms

Besides Parkinson’s disease typical triad of motor symptoms such as bradykinesia, resting tremor and rigidity, there is another spectrum of sensory features including auditory and ophthalmologic disruptions. Visual signs and symptoms include:

  • Convergence insufficency
  • Dry eyes
  • Decreased visual acuity
  • Blepharitis
  • Blepharospasm
  • Apraxia of eyelid opening
  • Visual hallucination


The impaired motor control in Parkinson disease is responsible for convergence insufficiency. This finding is more noticeable if near vision activities are performed and often causes diplopia and difficulty reading. Corneal erosions and lacrimal glands dysfunction occur as a result of concomitant entities including eyelid opening apraxia, decreased blink rate and reduced tear secretion. Visual hallucinations appear to be more frequent in patients treated with L-dopa and dopaminergics. The presence of visual hallucinations indicate a chronic evolution of the disease and have been associated with increased morbidity and mortality.

Management

Conventional therapy is the main treatment. If the patient is already being treated with dopamine replacement it can result beneficial to re-evaluate treatment adherence and assure correct dosage. Prism correction may also be recommended.

References

1.- Almer, Zina, Kathyrn S. Klein, Laura Marsh, Melissa Gerstenhaber, and Michael X. Repka. "Ocular Motor and Sensory Function in Parkinson's Disease." Ophthalmology: 178-82. Print.

2.- Straughan, S., Collerton, D., & Bruce, V. (2015). Visual Priming and Visual Hallucinations in Parkinson's Disease. Evidence for Normal Top-Down Processes. Journal of Geriatric Psychiatry and Neurology.

3.-Biousse, V., Skibell, B., Watts, R., Loupe, D., Drews-Botsch, C., & Newman, N. (2004). Ophthalmologic features of Parkinson's disease. Neurology, 177-180.

4.- L.A. Hunt, A.A. Sadun, C.J. Bassi. Review of the visual system in Parkinson's disease. Optom Vis Sci, 72 (1994), pp. 92–99