Retinal Disorders Flashcards
What type of equipment is used to examine the eye?
Indirect ophthalmoscope Biometry Perimetry Fundus camera Optical coherence tomography Fluorescein angiography Electrophysiology
Where are rods located?
Peripheral areas of the retina
What is a specific feature of the blind spot?
No rods or cones
What is electrophysiology?
Investigations recording electrical signals from the eye, optic nerve and brain in response to visual stimuli
What does an electroretinogram measure?
Retinal function
Records action potentials within retina
What does an electrooculogram measure?
Function of RPE and photoreceptors
What do visually evoked potentials measure?
Optic nerve function
Electrical activity in visual cortex
What could be the causes of sudden painless loss of vision?
Central retinal vein occlusion Central retinal artery occlusion Ischaemic optic neuropathy Stroke Vitreous haemorrhage Retinal detachment
What are the causes of central retinal vein occlusion?
Hypertension
Glaucoma
Hyperviscosity
Inflammation
What are the causes of central retinal artery occlusion?
Emboli
Inflammation
What are the different types of ischaemic optic neuropathy?
Arteritic
Non arteritic
How do you differentiate between the different types of ischaemic optic neuropathy?
Arteritic form will have raised inflammatory markers on blood analysis
What are the symptoms of giant cell arteritis?
Headache Scalp tenderness Jaw claudication Neck pain Nausea Loss of vision
What is the investigation for giant cell arteritis?
Temporal artery biopsy
What are the symptoms of optic neuritis?
Pain on eye movement
Reduced vision red desaturation
What is optic neuritis associated with?
Multiple sclerosis
What are the causes of gradual painless vision loss?
Cataract Refractive error Age related macular degeneration Open angle glaucoma Diabetic retinopathy
What are the risk factors for age related macular degeneration?
Age
Smoking
Poor diet
What are the signs of age related macular degeneration?
Distortion of vision
Struggle to read and recognise faces
What are the 2 types of age related macular degeneration?
Wet
Dry
What are the clinical signs of diabetic retinopathy?
Cotton wool spots
Exudates
Appearance of new vessels
What are retinal dystrophies?
Inherited conditions affecting photoreceptor function leading to progressive loss of vision
What are some examples of retinal dystrophies?
North Carolina macular dystrophy
Stargardt macular dystrophy
Cone dystrophy
Drug induced retinopathy
What type of drugs will cause retinopathy?
Anti malarials
Phenothiazines
Tamoxifen
How is gene therapy used in treatment of the retina?
Viral vector injected under the retina containing replacement gene into host DNA
