Duane's retraction syndrome

ratio of female to women with DRS

3:2

inherited or no

congenital

clinical signs

limited abd and add

- narrowing add palp fissure, widening on abd

- retraction of globe on adduction

how is convergence

reduced

what alphabet pattern

A and V pattern

what other signs seen on adduction

up/downshoots

associated ocular disorders

coloboma, lens opacities, microphthalmos, heterochromia

associated general conditions

klippel-feil

goldenhar's

moebius syndrome

what occurs in klippen-feil syndrome

congenitual fusion of 2 of 7 cervcical neck membrane

what occurs in goldenhar's sydndrome

hypoplasia face, low set ears, deafness, coloboma

moebius syndrome

underdeveloped/absence of 6th and 7th CN

Brown's type A classification DRS

limitation of abduction > adduction

brown's type B classification

limitation of abduction only

brown type C classification

limitation of adduction > abduction

Huber's type 1 DRS

limitation of abduction

huber type 2 DRS

limitation of adduction

huber type 3 DRS

limitation of abd + add

embryonic aetiology of DRS

disruption in 2nd month gestation

myogenic/mechanical aetiology of DRS

post-insertion of MR, LR inelastic and fibrotic, LR slippage over globe, won't relax in adduction causing retraction, when adudcting above or below midline, causing upshoot or downshoot

neurological-innervational cause of DRS

CCCD - cocontraction of MR and LR

- hypoplasia (malformed or absent) of 6th CN, innervation of LR by 3rd

why do fissure changes occur?

due to extra innervation

why are there upshoots/downshoots

LR slippage due to it being fibrotic and abnormal innervation to SR and LR

why are there limitations of eye movements

fibrotic, inelastic LR, simultaneous co-contraction of MR and LR

what does a smaller and squashed field in a hess indicate?

mechanical problem

differential diagnosis

6th NP and type B brown's (limitation of abd)

CH DSR vs 6NP

DSR - genetic conditions, 6NP - microvascular cause e.g. diabetes, obesity, hypertension, cholesterol

CHP DSR vs 6NP

both head turn to affected side

VA DSR vs 6NP

DSR - amblyopia in congenital

6NP - equal

convergence

DSR - typically reduced, 6NP - normal

motility DSR vs 6NP

ab/adduct restrict, upshoot/downshoot, globe retraction, palpebral fissure changes, A/V pattern

management for convergence problems

if CI, give exercises

surgery for type A (abd>add) ET

MR recession

what type of surgery avoided in DSR?

LR resection (strengthen) as LR fibrotic, can make retraction + adduction worse

surgery to reduce retraction

LR recession + MR recession, to alleviate LR tightness, recession may make ET worse so both done to counteract effect of recession

what's a faden?

weakens muscle in its field of action

surgery for a large AHP

faden of MR

bilateral MR recession

how does faden help a large AHP

put on MR of unaffected eye e.g. on a RE DRS, can't look right, so LE o/a, so prevents the o/a and allows eyes to align and reduce AHP

how is a upshoot/downshoot treated

faden

bifurcation LR with recession

what's bifurcation

- Y-split, incision made down middle of muscle belly and seperated into 2 parts, resutured above an below to give extra LR stability and prevent slippage

surgery for inc abduction

vertical transposition + MR recession

vertical transposition

SR and IR moved towards LR, contributing more to abduction movement

jensen's procedure

- inc abduction

- make incisions in muscles and put sutures to get abducting effect + less abducting effect

surgery for type C DRS large deviation

LR recession

upshoot/downshoot type C

LR recession

- faden

- bifurcation

large AHP

faden LR of unaffected eye

- bilateral LR recession

inc adduction

vertical transposition to MR, SR and IR transposed to MR