New research discovered that Leonardo da Vinci had a rare eye condition called’exotropia’,the condition is characterized by misalignment of one eye that turn out wards.
The condition affects 1% of world population says Christopher Tyler of City university of London and Smith Kettlewell Eye Research Institute in San Francisco.
For da Vinci,this seem to have affected the left eye making him see the world from different angle of flat canvas than in 3 Dimension like the rest of us;with one eye able to turn -10.3 degrees outward when relaxed and straight when focused.This made it easier for him to translate things on to the canvas,portraying depth and distance with accuracy.
CNN.com 18 October 2018
Exotropia is a form of strabismus (eye misalignment)occur anytime Intermittent or Constant,and is found on any group of people.
Causes ranges from 3rd nerve palsy or previous eye surgery or injury while childhood intermittent exotropia has no known cause.. (umkelloggeye.org)