450 likes | 848 Views
Strabismus. Reza Nabie MD Nikookari Eye Hospital Tabriz. Normal Visual Development - Normal vision develops as a result of both genetic coding and experience in a normal visual improvement - 6 weeks: maintain eye contact react with facial expression
E N D
Strabismus Reza Nabie MD Nikookari Eye Hospital Tabriz
Normal Visual Development - Normal vision develops as a result of both genetic coding and experience in a normal visual improvement - 6 weeks: maintain eye contact react with facial expression - 2-3 months: interested in bright objects • 4 months: disconjugate eye movements should be eliminated
Signs of actual poor visual development - Wandering eye movements - Lack of response to familiar faces and objects - Nystagmus - Staring at bright light - Forceful rubbing of eyes (oculodigital reflex)
Strabismus Definition : Any misalignment of visual axes Eyes as a sensorimotor unit
Tasks of Motor System : • enlarge the field of view • bring the image of object onto fovea • position the two eyes alignment
Most Important Deficient Of Strabismus: Loss of single Binocular vision • Amblyopia • Stereopsis • Contrast sensitivity • Color sensation • Spatial uncertainty • Increased perception and reaction time • Visual field • Visumotor performance
Benefits of Treating Strabismus • Functional • Psychosocial • Cosmetic
Types of Strabismus • Paralytic: 6th, 4th, 3th palsy • Horizontal: ET, XT • Restrictive: Blow-out fracture, Graves • Strabismus Syndrome :Duane Mobius
Types of Esotropia • Essential Infantil (Congenital) • Accommodative : • a.Refractive • b.Non-refractive(High AC/A ratio)
Horizontal Strabismus • Essential Infantile (congenital) ET
Characteristics: ◙ Most common deviation ◙ Onset by 6 mo ◙ FH of ET or strabismus ◙ Large angle ◙ No significant Refractive Error
Treatment : • Surgery is mainstay of treatment • Amblyopia treated before surgery
II) Accommodative ET Is secondary to hyperopia or overconvergence
Refractive Acc.ET • Hyperopia • Blurred Vision • Accommodation • Clear Vision +Convergence • Esotropia
Characteristics: • Hyperopia: Mean +3 • No ET with glass • Positive FH • Onset by 2-3 years • Treatment: Glass
Non-Refractive Acc.ET Ratio of convergence to accommodation is abnormally high Accommodation Over-convergence ET During Accommodation
Characteristics: • No Hyperopia or mild hyperopia • More ET at near than distance • Positive FH • Onset by 2-3 years Treatment: BifocalGlass
Characteristics: ◙ rare ◙ CNS evaluation indicated ◙ Positive FH ◙ Large Angle ◙ Onset by 6 months ◙ No significant refractive Error Treatment: As Congenital ET
Characteristics: ◙ Most common form of XT ◙ No amblyopia ◙ Positive FH ◙ Variable Angle ◙ Onset by 2- years ◙ No significant refractive Error Treatment:a Conservative if early periods b.Surgery if deviation significant
Paralytic Strabismus • Etiology: • Trauma(most common) • Vascular accident • Tumors • CNS Infection • Vaccination
Paralytic Strabismus I) Superior Oblique Palsy ◙ Hypertropia ◙ Torticoly
II) Sixth nerve Palsy ◙ Esotropia ◙ Abduction deficient ◙ Face turn
III) Third Nerve Palsy ◙ Large angle XT ◙ Globe fixed in Abduction ◙ Only abduction is seen ◙ Ptosis ◙ Dilated pupil
Treatment of Paralytic Strabismus • Congenital Palsy :Surgery • Acquired Palsy : • May be improved spontaneously • If not improved after 6 months surgery may be needed
Blow-out Fracture Restrictive Strabismus
Strabismus Syndromes • Duane Syndrome • Limitation of abduction • Normal or limited adduction • Globe retraction in adduction • May be Ortho , ET or XT