5 Disorders of the Eye Flashcards
What are the symptoms of orbital fracture?
Trauma lid swelling pain diplopia Reduced vision
What are signs of orbital fracture
Reduced vision, movement of eye and visual fidels
Enophthalmos (posterior displacement of eye)
What is an orbital rim fracture?
Fracture of bones forming outer rim, usually at sutures:
maxilla, frontal, zygomatic
What is a blowout fracture? Cause? What does it result in?
Partial herniation of orbital contents through orbit fractured wall.
Caused by blunt force trauma.
Muscles entrapment
Diplopia
Infection
Exophthalmos (increase intraocular pressure)
Infraorbital bleeding.
Which walls of the orbit are weakest? Where do contents herniate into in blowout fracture?
Medial - ethmoid sinus/sphenoid sinus
Inferior - maxillary sinus
What is the difference between a meibomian cyst and a stye?
Meibomian cyst - Blocked tarsal gland behind eyelashes within tarsal plate (lump behind eyelid)
Stye - Sebaceous gland infection at base of eyelash
Glands secrete oily material that forms cystic swelling if drainage is blocked.
What is glaucoma? What does it lead to?
Increased amount of aqueous humour in chambers –> Increased intraocular pressure
This compresses retinal arteries, damages retina and leads to loss of vision.
What is the difference between open angle and closed angle glaucoma?
Open angle
Outflow of aqueous humour through trabecular mesh is reduced/
Gradual reduction in peripheral vision til end stage blindness.
Closed angle
Iris forced against trabecular meshwork, preventing damage.
Ophthalmic emergency - instant blindness possible
What are the changes that occur in old age?
Presbyopia - lens becomes harder and more flattened with age, reducing focusing power
Cataracts - loss of transparency of lens and areas of opaqueness
What is conjunctivas? Symptoms? Cuase?
Inflammation of the outermost layer of the white of the eye and inner surface of the eyelid.
Pink/red eye
Pain burning scratchiness
Cause:
Viral then bacterial
Irritant
Allergy to pollen/amimal danader.
What is orbital cellulitis? Symptoms signs?
Inflammation of eye tissues behind the orbital septum
(A membraneous sheet that extends from orbital rims to the eyelids).
Acute spread of infection into the eye socket from adjacent sinuses or through blood.
Symptoms/signs
Fever, restricted eye movement, reduced vision/colour
Relative afferent pupil defect (pupil contracts less when bright light is swung from unaffected eye to affected eye) redness, swelling, pain
What is thyroid eye disease?
Autoimmune disorder affecting the orbit around eye.
Upper eyelid retraction, lid lag, swelling, redness, conjunctivitis.
Exophthalmos:
Protrusion of eye
Eyelids part more than normal
sclera visible all around the cornea and it is
Bilateral in Grave’s
Unilateral ain aneurysm/haematoma
What is papilloedema?
Swelling of optic disc visible during ophthalmoscopy.
Secondary to raised intracranial pressure
Resists venous return from eye
so fluid collects in retina producing swollen optic disc.
Loss of vision in retinal artery vs vein occlusion
RA - instant painless loss due to ischaemia
RV - slow painless
What is retinal detachment? Presentation?
Intraretinal space separates laters of retina in development.
Layers fuse in early fetal period, obliterating
Pigment layer is firmly fixed to choroid but neural layer is not firm.
Blow to eye –> detachment of retina
Presents with flashes of light, specks floating in front of eye.
