1.48 Eye Problems Flashcards
What is Band Keratinopathy….
Corneal disease - build up of calcium - cataract
What can Pin Holw differentiate between…
Reduced vision due to refractive error (glasses) or pathological cause (retinal damage etc.)
What is the vision needed for a uk driving license…
6/10
What are the examination findings with someone with a cataract…
• Clear Cornea • Cataract • Clear Vitreous • Normal retina No focal visual field defect
What are the types of cataracts …
Nucleus sclerosis - glare
Cortical - reduce visual acuity and glare
What are the post operative complications of cataracts…
• Posterior capsule opacification (PCO)
• Infection
• “endophthalmitis” - staph epidermidis most common agent - treated with antibiotics injection directly into the eye - severe loss of vision results
• blepharitis is a risk factor for endophthalmitis
• Corneal oedema (swelling of the cornea)
• Cystoid macular oedema (swelling of the macula)
• Raised intra ocular pressure
Retinal detachment
What can cause a chiasmal syndrome or lesion?
Pituitary adenomasare the most common cause; however, chiasmal syndrome may be caused bycancer, or associated with other medical conditions such asmultiple sclerosisandneurofibromatosis.
What can constrict the gross peripheral field vision?
• Chronic Glaucoma • Chronic optic disc swelling (papilloedema) • Retinitis Pigmentosa - affects the retina • Functional • Visual acuity may be normal yet patient functionally blind
What does a macula lesion cause…
Unilateral Central Scotoma with Distortion
What does retinal detachment cause..
Unilateral Peripheral/Total vision loss
What does an acute optic nerve lesion cause…
Unilateral Central Scotoma
What does an acute optic nerve lesion cause (glaucoma or pappilloedoma)…
Peripheral constriction (tunnel vision)
What does a lesion in the chiasm result in…
Bitemporal Hemianopia (hetero)
What does a lesion in the post chiasm result in…
Loss of field opposite to site of lesion in both eyes
Eg left optic tract lesion causes inner field loss in left eye and outer field loss in right eye
explain and say what causes total afferent pupil defect in one eye….
• Both pupils same size at rest • Light to affected eye • No constriction of either pupil • Light to normal eye • Both pupils constrict • Light back to affected eye Both pupils dilate On optic nerve sections or retinal detachment
Explain and say what causes efferent pupil defects…
• Pupils different sizes at rest • Sphincter (Constriction) (failure) • Parasympathetic via IIIn • Dilator (failure) • Sympathetic via Carotid artery Damage to iris
What could causes failure of the pupils to constrict…
Preganglionic from midbrain to orbit with IIIn
• compressed in brain swelling
• compressed by aneurysms in circle of Willis
• seen as part of IIIn palsy
• Postganglionic from ciliary ganglion to eye via
short posterior ciliary nerves
• affected by lesions of ciliary ganglion
eg Adie’s pupil
• Pathology of pupil sphincter
• eg high intraocular pressure in acute glaucoma
Ischeamia - high pressure - cant constrict
What could cause failure of the pupils to dilate…
• Damage to ocular sympathetic supply known as Horner’s Syndrome - Failure of pupil dilation ○ Partial Ptosis (drooping of eyelid) ○ If preganglionic § Anhydrosis (Failure to sweat on affected side) § If congenital (or onset prior to 12 months); iris heterochromia • Preganglionic from T1 to superior cervical ganglion • compressed in lung tumours • compressed by cervical rib • Postganglionic from SCG to eye via ICA via long posterior ciliary nerves • affected by lesions of ICA eg dissection, aneurysm • Pathology of pupil dilator eg uveitis
What can cause an acute red eye….
Angle closure glaucoma Endophthalmitis Conjuctivitis - bacterial, viral, fungal Corneal ulcer Episcleritis Scleritis Acute anterior uveitis Subconjuctival hemorrhage Trauma Globe puncture
What can cause painful acute vision loss…
• Acute glaucoma
• Other causes of red eye
Optic neuritis
What can cause painless acute visual loss…
• Vitreous haemorrhage • Retinal detachment • Central Retinal Artery/Vein Occlusion • Wet Age Related Macular Degeneration • Ischaemic Optic Neuropathy Arteritic / Non Arteritic
