STRABISMUSAMBLIOPIABINOCULAR VISION Dr ule Ziylan Extraocular muscles n

STRABISMUS-AMBLIOPIABINOCULAR VISION Dr. Şule Ziylan

Extraocular muscles n n n Nervus abduscens Nervus trochlearis Nervus oculomotorius

Extraocular muscles

Extraocular muscles n In order to see correctly both eyes must move in same direction. This is done by pulling by one muscle in one direction and relaxing of other muscle.

Extraocular muscles n n n Cranial Nerve III medial rectus muscle, superior rectus muscle, inferior oblique muscle Cranial Nerve IV superior oblique muscle Cranial Nerve VI lateral rectus muscle

Extraocular muscles

Binocular single vision To see one object both eyes must look at it at the same time. Each eye sees it from different angle and each eye sends a slightly different picture to the brain (Binocular vision). Brain blends the two picture to give a three dimensional image. This process is known as fusion and it gives the ability to judge the relative distance in two objects (depth perception).

Binocular single vision Seeing simultaneously with two eyes

Binocular single vision Fusion

Stereopsis

? ? ? n n n When should be the first examination? The propiate time of vision testing? Is a squint normal in an infant?

Teller test

Strabismus Misalignment of the eyes, known as strabismus, is a common problem in childhood. Strabismus is usually recognized by parents as a crossing or drifting out of one or both eyes. The drifting may be constant or intermittent. The risk of strabismus is much higher when a family history of "lazy eye" or crossed eyes is present.

Strabismus

Nonparalytic strabismus * Inward squint ( esotropia)

Nonparalytic strabismus * Outward squint ( exotropia)

Nonparalytic strabismus * Special forms

Paralytic strabismus If the muscles are not coordinated the images of to eyes send two brain will not fuse and one gets double vision. The child quickly and unconsciously learns to ignore the image of one eye (suppression) and the eye becomes lazy (amblyopic)

Paralytic strabismus n Sudden onset n Diplopia Systemic investigation?

Paralytic strabismus n 3. nerve palsy ( N. Oculomotorius) n 4. nerve palsy ( N. Trochlearis) n 6. nerve palsy ( N. Abduscens)

Paralitik şaşılık * 6. nerve palsy

AMBLYOPIA The subvision without any organic disease

? ? ? n The age of amblyopia risk? n The age of amblyopia treatment?

Amblyopia n Strabismic amblyopia n Anisometropic amblyopia n Deprivation amblyopia

THE PREVENTION AND TREATMENT OF AMBLIOPIA n n Examination at 1. and 6 months of age Early diagnosis of strabismus Early diagnosis of refractive errors Oclusion therapy