3.2 Duane's Retraction Syndrome

Question 1

What are the different aetiologies with Duanes?

Answer 1

Innervation of LR by extra branches of the IIIrd CN in place of absent VIth nerve fibres.
Absent VIth nerve nucleus
Abnormal LR
Bursa like structure separating the tendon and trochlea
Co-contraction theory
Mechanical
Genetic abnormalities

Question 2

List some of the ocular associations with Duanes

Answer 2

o Coloboma
o Heterochromia irides
o Microphthalmos
o Cataract
o Congenital crocodile tears
o Persistent pupillary membrane
o Marcus Gunn jaw-winking phenomenon

Question 3

List some of the systemic associations with Duanes

Answer 3

o Goldenhar’s syndrome
o Klippel-Feil syndrome
o Hearing loss, abnormal ear formation
o Thalidomide syndrome
o Cervical spina bifida
o Wildervanck syndrome
o Moebius syndrome

Question 4

What does CCDD stand for?

Answer 4

Congenital cranial dysinnervation disorder

Question 5

What are the main elements of CCDD’s?

Answer 5

• Onset at birth
• Cases can be isolated or familial
• A genetic abnormality has been identified in some familial cases
• Non-progressive
• Arises from defects affecting the brainstem and cranial nerve development

Question 6

What is the onset of Duanes?

Answer 6

Congenital

Question 7

What are the classifications/types of Duanes?

Answer 7

Type A, B and C

Question 8

Describe Duanes Type A

Answer 8

Limited abduction and less limited adduction (ABduction limitation >ADduction limitation)

Question 9

Describe Duanes Type B

Answer 9

Limited abduction but normal adduction
(ABduction limitation only)

Question 10

Describe Duanes Type C

Answer 10

Limitation of adduction exceeds limitation of abduction
(ADduction limitation > ABduction limitation)

Question 11

What are the four variants of Duanes?

Answer 11

Vertical retraction syndrome
Congenital adduction deficit with synergistic divergence
Acquired retraction syndrome
Co-innervation with other branches of the IIIrd nerve

Question 12

What is vertical retraction syndrome?

Answer 12

o Retraction and narrowing on elevation or depression
o Cause: Anomalous orbital structures rather than aberrant innervation.
(RARE)

Question 13

What is congenital adduction deficit with synergistic divergence?

Answer 13

o Exotropia with marked limitation of adduction
o On attempted adduction, the eye moves further into abduction
o Also known as ‘the splits’
(RARE)

Question 14

What is acquired retraction syndrome?

Answer 14

o Also known as ‘pseudo-Duane syndrome’
o Limitation of abduction
o Globe retraction in abduction
o Causes: trauma, systemic illness, orbital tumours

Question 15

What is co-innervation with other branches of the third nerve?

Answer 15

o Innervation from the third nerve to both the LR and vertical muscles
o Co-innervation occurs causing an up-drift and down-drift on horizontal gaze

Question 16

List features of Duanes

Answer 16

• Limitation of horizontal eye movements
• Abnormal head posture (to achieve field of BSV)
• Manifest strabismus when the head is straight
• Retraction of the globe on adduction with narrowing of the palpebral fissure
• Widening of the palpebral fissure on abduction
• Up shoot or down shoot on adduction
• Binocular single vision is usually present but with reduced stereo and poor convergence in some cases
• Rarely report diplopia
• Other developmental abnormalities (involving ear, eye, kidneys and genetic defects)

Question 17

What are some extra orthoptic assessments to perform on Duanes patients?

Answer 17

o Hess chart (head kept straight and static)
o Field of BSV (head kept straight and static)
o Routine cycloplegic refraction and fundus check should be done in all cases (refractive error is neither more or less common in Duane’s when compared to the average population).

Question 18

Name some differentials of Duanes

Answer 18

Trauma - Blow out fracture
Moebius syndrome
Congenital 6th nerve palsy
Infantile ET

Question 19

What are non-surgical management options for Duanes?

Answer 19

o Correct any refractive error (hypermetropia may improve alignment in ET’s)
o Treat any amblyopia
o In uncommon cases of decompensation and diplopia, prisms should be trialled

Question 20

When would we perform surgery on Duanes patients?

Answer 20

 Decompensation
 Moderate AHP and neck pain
 Poor cosmesis (large esotropia)

Question 21

What does surgery of Duanes aim to achieve/correct?

Answer 21

 Improve field of BSV
 Reduce AHP
 Improve cosmesis if no BSV

Question 22

What is the caveat we need to consider with surgical intervention on Duanes

Answer 22

AVOID SURGERY IF POSSIBLE - surgery outcome is unpredictable , results can range from no change in limitation in elevation in adduction to a complete superior oblique palsy.

Question 23

What are the surgical options for Duanes type A and B (esotropia)?

Answer 23

• Recess one or both MR depending on angle – recommended
• Vertical muscle transposition surgery

Question 24

What are the surgical options for Duanes type C (exotropia)?

Answer 24

• Unilateral or bilateral LR recessions

Question 25

What are the surgical options for Duanes globe retraction, up-shoots and down-shoots?

Answer 25

• Ipsilateral MR & LR recessions to reduce effect of co-contracture

Question 26

What are the considerations of using BOTOX in Duanes patients?

Answer 26

 Improves alignment
 Improves BSV
 Improves AHP and neck symptoms
 Short term
 Does not improve retraction or palpebral fissure changes

Question 27

What do parents of Duanes patients need to be aware of?

Answer 27

In most cases friends/peers do not notice strabismus as head is moved instead of the eyes
In most cases patients will still be able to drive
Surgical management will not fully restore eye movements

Question 28

Why should we monitor children with Duanes?

Answer 28

• To ensure BSV is not disrupted in PP
• Amblyopia is occasionally found and so we must monitor children to ensure their VA is developing in accordance with age norms.
• Trust policies differ surrounding how frequently monitoring occurs.
• Ansons and Davis (2014) suggests to keep children under observation, monitor carefully for any refractive error and amblyopia
• Annual reviews and discharge should be considered when:
  o Uniocular vision is stable and at an appropriate level for age
  o BSV is stable and appropriate for age
  o No parental concerns