Please enable JavaScript.
Coggle requires JavaScript to display documents.
Duane Syndrome - rare congenital eye movement disorder - Coggle Diagram
Duane Syndrome - rare congenital eye movement disorder
Facts
Most are diagnosed by age 10
More common in girls (60%) than boys (40%)
80% of cases one eye is affected - most often the left
70% its the only disorder
30% other conditions and syndromes
Malformation of skeleton, ears, eyes, kidneys and nervous system
Some eye muscles contract when they shouldn't, some eye muscles don't contract when they should
Limits the ability to move eyes toward ears or toward the nose
3 Types
Type 1 - limited ability to move eyes outward toward ears, ability to move eye inward is normal
Eye opening narrows and eyeball pulls in when looking at nose
78% of all cases
Type 2 - limited ability to move eyes inward toward nose, outward ability is normal
Eye opening narrows and eyeball pulls in when looking toward nose
7% of all cases
Type 3 - limited ability to move outward and inward
15% of all cases
Causes
Lack of abducens nerve and 6th cranial nerve
Several factors possible
Genetic or environmental disturbance during development
Cranial nerves and ocular muscles develop during 3rd-8th week of pregnancy
Diagnosis -clinical findings
Mutation of gene CHN
Most likely genetic or environmental