Occuloplastics Flashcards
Which muscles open the eye and what innervates them?
Levator Palpebrae Superioris (CN3)
Mullen’s muscle (sympathetic)
Which muscle closes the eye?
Orbicularis oculi (facial nerve)
List the layers of the eyelid from internal to external
Conjunctiva
Tarsus (containing meibomian glands)
Orbicularis oculi
Skin
Which factors can cause acquired ptosis?
Involutional Myogenic (myasthenia gravis) Neurogenic (3rd nerve/horner's) Mechanical (hemangioma) Trauma
What is ectropion?
Turning outwards of the eyelid margin
What are some causes of ectropion?
Ageing changes
Facial nerve palsy
Cicatricial (scarring)
Mechanical
What is the risk of ectropion?
Metaplastic changes in exposed conjunctiva
What is entropion?
Rolling in of the eyelid margin
What causes entropion?
Involution
Trauma
Cicatricial
List the bones of the orbit
Frontal Maxillary Zygomatic Sphenoid Lacrimal Ethmoid Palatine
What travels through the optic canal?
Optic nerve
Ophthalmic artery
Sympathetic nerve plexus
Which 4 things differentiate preseptal cellulitis from orbital cellulitis?
Optic nerve defects (VA decrease, VF decrease, RAPD)
Ophthalmoplegia
Kimosis
Proptosis
What is the most common cause of orbital cellulitis?
Sinusitis
What is the pathogenesis of thyroid eye disease?
Infiltration of orbital tissues by inflammatory cells due to auto-immunity to humoral antigens
What are the classic signs of orbital fracture?
Hypotropia
Enopthalmos
Restricted motility
Infra-orbital anesthesia
Describe the difference between stye and chalazion?
A stye is painful staph infection at the eyelash
A chalazion is a painless granuloma of a meiobomian gland
Stye is treated with warm compress and antibiotic ointment
Chalazion is often self-resolving but can be excised
What is xanthelasmas?
Yellowish sessile plaques associated with hypercholesterolaemia
Which types of malignancy occur on the eyelid?
BCC
SCC
Both require excision
How do we treat congenital nasolacrimal duct congestion?
Conservative Probing and syringing Intubation/dacryoplasty Dacryocystorhinostomy 95% resolve conservatively by 1 year
