Duane Retraction Syndrome

Neurophthalmologic condition associated with abnormal ocular movement, usually not accompanied by other congenital anomalies.

Stilling Turk Duane Syndrome.

Duane retraction syndrome (DRS) is an unusual form of congenital strabismus and accounts for 1 to 4% of children with strabismus. It is slightly more common in females than in males (about 60:40), often is bilateral (2057%), and is significantly more frequent in the left eye (about 3-4:1). Reported frequencies vary widely.

Approximately 56 to 90% are sporadic cases. In the residual cases, a positive family history with autosomal dominant transmission has been suggested, although some cases with most likely autosomal recessive inheritance have been reported. Several gene defects can account for hypoplastic or absent brainstem motor neurons and aberrant innervation and therefore have been linked to DRS. Defects have been mapped to loci 2q31, 4q27-31, 8q12.2-q21.1, and 22pter-22q11.2, to mention a few.

Innervation of the lateral rectus muscle emanates from axons of oculomotor nuclei, which supposedly supply the medial rectus muscle. The abducens nucleus may be hypoplastic or even absent. Attempted adduction of the eye basically results in simultaneous contractions of the lateral and the medial rectus muscle, with the net effect being retraction of the globe. At the same time, the palpebral fissure narrows and horizontal eye movement is limited (depending on the type of DRS, abduction is severely compromised). A teratogenic event (e.g., thalidomide exposure) between days 20 and 35 of gestation has been held responsible for the genetic defect.

Severe limitation of horizontal eye movement accompanied by narrowing of the palpebral fissure and eyeball retraction with attempted adduction leads to the diagnosis of DRS.

Different classifications have been suggested for DRS. The following classification is based on EMG findings:

• Type I: Abduction is more compromised than adduction, which results in globe retraction and narrowing of the palpebral fissure, whereas abduction results in widening of the palpebral fissure. Adduction, but not abduction, shows EMG activity in the lateral rectus muscle. This type accounts for 70 to 90% of cases.
• Type II: Adduction is absent or limited with exotropia of the affected eye. Attempted adduction results in globe retraction. Adduction and abduction result in EMG activity in the lateral rectus muscle.
• Type III: Both adduction and abduction are severely limited. Attempted adduction results in globe retraction and narrowing of the palpebral fissure. EMG activity can be recorded for the lateral and the medial rectus muscles during attempted abduction and abduction.

In addition to the described horizontal restrictions of eye movement, vertical eye movement anomalies are possible.

A few other anomalies have been reported in conjunction with DRS, including other ocular anomalies such as anisometropia, amblyopia (both in approximately 15% of DRS patients), anisocoria, ptosis, and nystagmus. Conductive hearing loss and sensorineural hearing loss (each in approximately 5% of cases) have been reported. Furthermore, DRS has been described in patients with Arnold-Chiari I Syndrome, cerebro-oculofacioskeletal syndrome, Goldenhar syndrome, Holt-Oram syndrome, or Rubinstein-Taybi syndrome. DRS can be associated with intracerebral vascular malformations.

No specific anesthetic problems with DRS. However, the frequent association of this disorder with other anomalies or syndromes indicates the need for thorough and careful examination of the patient to exclude more anesthesia relevant findings.

Dictated by the syndrome associated with DRS. Isolated DRS should not affect anesthetic management and outcome.

Isolated DRS is not expected to have any pharmacological implications.

The following syndromes must be considered in a patient with DRS.

Arnold-Chiari Syndrome: Defect in the formation of the lower portion of the medulla (posterior fossa). Can be associated, according to the type, with hydrocephalus, raised intracranial pressure, and respiratory and cardiac center dysfunction. Infants may present with vomiting, mental impairment, and weakness. Limb paralysis is possible. The presence in adolescents usually is milder. Dizziness, weakness of the legs, headaches, double vision, or deafness may be present. Raised intracranial pressure. In type I, cerebellar displacement into the spinal canal occurs; however, hydrocephalus and syringomyelia are variable.

Pena-Shokeir Syndrome Type II: Rapidly progressive congenital neurologic disorder.

Goldenhar Syndrome: Common birth defect of vascular origin involving first and second branchial arch derivatives resulting mainly in facial and vertebral anomalies with potentially severe anesthetic implications (both caused by reconstructive surgery and difficult intubation).

Holt-Oram Syndrome: Inherited malformation syndrome characterized by the association of a congenital heart disease (septal defect) and upper limb malformation (underdevelopment of bones and/or extra bones).

Rubinstein-Taybi Syndrome: Rare syndrome with craniofacial anomalies and complex and multiple malformations of the cardiac, digestive, and respiratory systems.