Visual system alterations may signal onset of Parkinson s

London July 11 (IANS) Experiencing changes in the visual system such as an inability to perceive colours may act as important biomarkers for the early detection and monitoring of Parkinson s disease according to a new study.

"Just as the eye is a window into the body the visual system is a window into brain disorders " said lead researcher Alessandro Arrigo from the Vita-Salute San Raffaele University in Italy.

Parkinson s disease is a neurodegenerative condition caused by neuronal loss in several brain structures and is characterised by tremors rigidity or stiffness throughout the body and impaired balance and coordination.

"Although Parkinson s disease is primarily considered a motor disorder several studies have shown that non-motor symptoms are common across all stages of the disease. However these symptoms are often undiagnosed because patients are unaware of the link to the disease and as a result they may be under-treated " Arrigo said.

Non-motor symptoms including visual alterations such as an inability to perceive colours a change in visual acuity and a decrease in blinking which can lead to dry eye may precede the appearance of motor signs by more than a decade Arrigo said.

The study published online in the journal Radiology also revealed significant abnormalities within the visual system brain structures of Parkinson s disease patients including alterations of optic radiations a reduction of white matter concentration and a reduction of optic chiasm volume.

--IANS
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