TOPIC 1: AGEING EYES Flashcards
How does ageing affect vision in terms of Binocular vision?
-Positive fusional reserve decrease, negative fusional reserve constant
-NPC reduce 1cm
-decreased saccades facility , increased number of saccades to maintain fixation
- more vertical eye movement restrictions
How does ageing affect vision in terms of Peripheral vision?
-VF decreases
-lose of 0.7 dB per decade of life in peripheral vision on average
How does ageing affect vision in terms of Contrast sensitivity?
CS reduced esp at intermediate and high spatial freq
How does ageing affect vision in terms of Dark adaptation
DA slower
How does ageing affect vision in terms of Glare recovery
glare recovery slower
How does ageing affect vision in terms of Refractive error?
- hyperopic shift +1.25D
-myopic shift linked to nuclear sclerosis
-increased ATR astig
What are the 11 common anatomical changes in the eyelid and adnexa?
-dermatochalasis
-ptosis
-ectropion / entropion
-squamous papilloma
-xanthelasma (associated with high cholesterol)
-Seborrhic keratosis (benign growth)
-Basal cell carcinoma (most common eyelid cancer)
-Squamous cell carcinoma (second most common eyelid cancer)
-Decreased aqueous production
-Decreased mucin production
-Chronic MGD / dry eyes
What are the 2 common anatomical changes in the conjunctiva
Pterygium
pinguecula
What are the 10 common anatomical changes in the anterior chamber and lens?
Anterior chamber:
-Shallower depth due to increase in crystalline lens size
-decreases from 3.6mm in young adult to 3mm in a 70yr old
-Trabecular meshwork thickens
-increased pigmentation reduces drainage of aqueous
Ciliary body
-thickens and shortens
-atrophy with age
-less aqueous humour production (decreased by 25% each decade after 30 years of age)
Iris
-Senile miosis, more sluggish pupil response
Crystalline lens
-increased size and rigidity
-decreased elasticity and transparency / cataract formation
What are the 6 common anatomical changes in the cornea?
-Corneal arcus (lipid deposits in stroma)
-limbal girdle of Vogt (whitish calcium and hyalin deposits)
-Corneal farinata. (fine dust-like dots due to abnormal stromal keratocytes)
-Hudson-Stahli line (iron deposits on corneal epithelium)
-Hassle-Henle bodies (degenerating endothelial cells produce localised nodular thickening of the Descemet’s membrane)
-Crocodile shagreen (polygonal opacities in the stroma representing disorganisation of the collagen fibrils)
What is the common anatomical change in the vitreous?
Liquefaction and shrinkage ( aka syneresis)
What are the 2 common anatomical changes in the chorioid?
-Atrophic changes such as PPA is common
-Diuse clumping of pigment occurs, and increases fundus tessellation
What are the 3 common anatomical changes in the retina
-Loss of foveal reflex and retinal sheen due to vitreous liquifaction
-Generalised loss of photoreceptors and ganglion cells
-20-30% RNFL thinning, especially in the superior quadrant
