ESOTROPIA

Question 1

concomitant - definition

Answer 1

variability of the angle of deviation is within 5 Δ in different horizontal gaze positions

Question 2

Early-onset (congenital, essential infantile) - when, features

Answer 2

developing within the first 6 months of life, no significant refractive error and no limitation of ocular movements. • angle fairly large (>30 Δ) and stable. • Fixation alternating in the primary position • cross-fixating in side gaze

Question 3

Early-onset (congenital, essential infantile) - nystagmus

Answer 3

• Nystagmus is usually horizontal. • Latent nystagmus (LN) is seen only when one eye is covered and the fast phase beats towards the side of the fixing eye. • Manifest latent nystagmus (MLN) is the same except that nystagmus is present with both eyes open, but the amplitude increases when one is covered. • Asymmetry of optokinetic nystagmus is present.

Question 4

Early-onset (congenital, essential infantile) - late motor abnormalities

Answer 4

• Inferior oblique overaction may be present initially or develop later. • Dissociated vertical deviation (DVD) develops in 80% by the age of 3 years

Question 5

Early-onset (congenital, essential infantile) - differential

Answer 5

bilateral congenital sixth nerve palsy, secondary (sensory) esotropia due to organic eye disease, nystagmus blockage syndrome in which convergence dampens a horizontal nystagmus, and mechanical limitations of eye movement such as Duane and Möbius syndromes and strabismus fixus

Question 6

Early-onset (congenital, essential infantile) - treatment

Answer 6

either recession of both medial recti or unilateral medial rectus recession with lateral rectus resection. • An acceptable goal is alignment of the eyes to within 10 Δ, associated with peripheral fusion and central suppression.