12 - Special Motility Disorders Flashcards
(Congenital Cranial Dysinnervation Disorders)
Exemples de Congenital Cranial Dysinnervation Disorders
Included in this group are Duane retraction syndrome, congenital fibrosis of the extraocular muscles, Möbius syndrome, and some cases of congenital fourth nerve palsy.
In recent work, congenital Brown syndrome has been postulated to be a form of CCDD.
(Duane Retraction Syndrome)
V ou F : Duane retraction syndrome is a spectrum of ocular motility disorders
Vrai. Duane retraction syndrome is a spectrum of ocular motility disorders.
(Duane Retraction Syndrome)
Définir le Duane retraction syndrome?
Duane retraction syndrome is a spectrum of ocular motility disorders characterized by anomalous co- contraction of the medial and lateral rectus muscles on actual or attempted adduction of the involved eye or eyes; this co- contraction causes the globe to retract.
(Duane Retraction Syndrome)
V ou F : Horizontal eye movement are not limited in both abduction and adduction.
Faux. Horizontal eye movement can be limited to various degrees in both abduction and adduction.
(Duane Retraction Syndrome)
Causes expliquant un upshoot ou un downshoot lorsque l’oeil ADD?
- An upshoot or downshoot often occurs when the affected eye is innervated to adduct; vertical slippage of a tight lateral rectus muscle by 1–2 mm, which has been demonstrated by magnetic resonance imaging (MRI) studies, is the typical cause.
- Less commonly, anomalous vertical rectus muscle activity is responsible for upshoots and downshoots.
(Duane Retraction Syndrome)
2 syndromes avec atteintes systémiques associés au Duane retraction syndrome?
Although most affected patients have Duane retraction syndrome alone, many associated systemic defects have been noted, such as Goldenhar syndrome (hemifacial microsomia, ocular dermoids, ear anomalies, preauricular skin tags, and eyelid colobomas) and Wildervanck syndrome (sensorineural hearing loss and Klippel- Feil anomaly with fused cervical vertebrae).
(Duane Retraction Syndrome)
Qu’est-ce que le syndrome Goldenhar?
Goldenhar syndrome
* hemifacial microsomia
* ocular dermoids
* ear anomalies
* preauricular skin tags
* eyelid colobomas
(Duane Retraction Syndrome)
Qu’est-ce que le syndrome Wildervanck?
Wildervanck syndrome
* sensorineural hearing loss and Klippel- Feil anomaly with fused cervical vertebrae.
(Duane Retraction Syndrome)
Rx tératogène associé au Duane retraction syndrome?
Studies of patients with Duane retraction syndrome related to prenatal thalidomide exposure show that the under lying defect in development occurs between the fourth and sixth weeks of gestation.
(Duane Retraction Syndrome)
Type d’acquisition/transmission?
Most cases of Duane retraction syndrome are sporadic, but approximately 5%–10% show autosomal dominant inheritance.
(Duane Retraction Syndrome)
% de patients avec un autosomal dominant inheritance?
Most cases of Duane retraction syndrome are sporadic, but approximately 5%–10% show autosomal dominant inheritance.
(Duane Retraction Syndrome)
Prévalence H versus F?
A higher prevalence in females is reported in most series, and there is a predilection for the left eye.
(Duane Retraction Syndrome)
Prévalence OD versus OS?
A higher prevalence in females is reported in most series, and there is a predilection for the left eye.
(Duane Retraction Syndrome)
Quelles sont les anomalies innervationnelles associées au Duane retraction syndrome?
- In most anatomical and imaging studies, the nucleus of the sixth cranial nerve is absent or hypoplastic and an aberrant branch of the third cranial nerve innervates the lateral rectus muscle.
- Results of electromyographic studies have been consistent with this finding.
(Duane Retraction Syndrome)
Ductions forcées N ou aN dans le Duane retraction syndrome?
Although Duane retraction syndrome is considered an innervational anomaly, tight and broadly inserted medial rectus muscles and fibrotic lateral rectus muscles, with corresponding forced duction abnormalities, are often encountered during surgery.
(Duane Retraction Syndrome)
Classification du Duance retraction syndrome?
- Type 1 refers to poor ABDuction, frequently with esotropia in primary position
- Type 2 refers to poor ADDuction and exotropia
- Type 3 refers to poor ABDuction and ADDuction, with esotropia, exotropia, or no primary position deviation
The spectrum of dysinnervation among cases means that classification of patients based on these categories can be arbitrary in some situations, especially in deciding between type 1 and type 3.
(Duane Retraction Syndrome)
% de patients avec une atteinte bilatérale?
Approximately 15% of cases are bilateral; the type may differ between the 2 eyes.
(Duane Retraction Syndrome)
V ou F : le type de Duane retraction syndrome peut différer entre les deux yeux.
Vrai. Approximately 15% of cases are bilateral; the type may differ between the 2 eyes.
(Duane Retraction Syndrome)
Qu’est-ce que le Synergistic divergence dans le Duane retraction syndrome?
- Synergistic divergence is a rare and bizarre motility disturbance that is often classified as a fourth type of Duane syndrome.
- There is usually exotropia, and when the affected eye looks in the direction that should result in adduction, it actually abducts even further— a finding colorfully described as “the ocular splits.”
- Synergistic divergence can be unilateral or bilateral and can be due to biallelic COL25A1 mutations.