Duanes Retraction Syndrome

Duanes Retraction Syndrome
SYMPTOMS Diplopia, Typically normal vision
SIGNS Typically unilateral
Non-progressive strabismus in primary gaze with compensating head position to align the eyes, May see upshoots or downshoots with adduction (Leash phenomenon), Globe retraction with narrowing of the palpebral fissure when adducting, Possible amblyopia, Hyperopic refractive error that is typically greater than +1.50, Poor binocular vision, Possible morning glory optic nerve
Type I (most common presentation): Esotropia in primary gaze with a head turn toward the affected side. Limited or absent abduction with normal or slightly limited adduction
Type II: Exotropia in primary gaze with a head turn towards the side that is not affected. Limited or absent adduction with normal or slightly limited abduction
Type III: Either an esotropia or exotropia with a head turn toward the affected side. Limited or absent abduction and adduction
WORK-UP Pupils, EOMs, Cover test, Cycloplegic refraction, Full eye exam with dilation, Strabismus evaluation, Forced duction testing
TREATMENT Prescribe glasses with best correction and possible prism
Recommend amblyopia/strabismus therapy if needed
Refer to a pediatric ophthalmologist for a surgery consult especially if one of the following is present: A head turn that is ≥ 15 degrees, A significant deviation in primary gaze, Reduction of the palpebral fissure ≥ 50% when adducting
Refer to a pediatrician if suspecting a systemic association
FOLLOW-UP If prescribing correction with or without prism, the patient should be seen back in 1 month, 3-6 months, and then yearly
If getting ocular surgery, the patient should be seen back once stable for a follow-up and refraction
ADDITIONAL LAB | TESTS About 30% of patients with duanes retraction syndrome can be associated with other congenital anomalies and should be ruled out: Okihiro syndrome, Wildervanck syndrome, Moebius syndrome, Holt-Oram syndrome, Goldenhar syndrome
ETIOLOGY Congenital cranial dysinnervation disorder: Abnormal development of the pontine abducens nucleus or nerve which causes poor innervation of the lateral rectus muscle (this will lead to fibrotic changes in the lateral rectus muscle). There is also aberrant innervation of the lateral rectus by the oculomotor nerve. May also be associated with polymorphisms such one involving CHN1
DIFFERENTIAL DX Brown syndrome, Cranial nerve 6 palsy, Congenital esotropia
NOTES The majority of cases involving duanes retraction syndrome are isolated
Patients with a polymorphism of CHN1 may also have involvement of Cranial nerve 2, 3, and 4