About age related changes in your eyes

1. AGE RELATED CHANGES IN THE
EYE?
“ARE WE AWARE ABOUT IT”
Hira Nath Dahal

3. • Decreased visual field
• corneal hypoxia
dermatochalasisptosis
Periorbit and eyelid

4. skin & soft tissue atrophy
glabellar rhytids
poliosis
orbital septal dehiscene ⇒ herniation of orbital fat
lacrimal gland dysfunction, ↓ed tear production,
meibomian gland disease & goblet cell dysfunction ⇒
dry eye

5. LID LAXITY ⇒ ENTROPION,
ECTROPION
• associated with ageing,
• both can be successfully treated with
surgery if they produce discomfort or a
threat to vision.

7. CONJUNCTIVA:
• atrophy & degeneration
• ↓ in no. & height of epithelial cells
• shortening of inferior fornix
• the number of mucous cells decreases leading to
dry eye.

8. CORNEA:
• ↓ed corneal sensitivity
• ↑ against-the-rule astigmatism
• no. of the people having with-the-rule astigmatism ↓es with
age
• Arcus senilis
• corneal endothelial cell population decreases along with
polymegathism and pleomorphism

9. fig: Typical age-related changes including sagging of the upper
lid, loss of the normal upper lid crease, eyelid wrinkling and arcus
senilis.

10. ANTERIOR CHAMBER:
• depth ↓es with age, causing
• the increment in the refractive power of the eye
(↑ myopia)
• More interference with aqueous outflow

11. PUPIL AND UVEA:
• senile miosis
• due to
• atrophy of the dilator muscle fibres,
or
• an increased rigidity of the iris blood
vessels, or
• both
• ↓ retinal blur circles and retinal illuminance

12.  less difference in the diameter of the pupil in the light- and
dark-adapted state
 less reactive to light
 slight ↑ in the latency of pupillary responses
 hypertrophy of ciliary muscle

13. LENS:
• Morphological Changes:
• ↑ in both the mass & dimension of the lens
• axial thickness of the lens ↑es by about 28% by age 70
over that which existed at age 15 to 20 yrs

14. • the nuclear thickness remains constant while the cortical
thicknesses increase
• the anterior cortex increases by 0.6mm & the posterior,
by 0.4mm
• flattening of the anterior lens surface & conical bulging of
the posterior lens surface

15. LENS:…
 Morphological Changes:
 epithelial cells- becomes flatter & density ↓es
 lens fibers- total loss or partial degradation of a no. of plasma
membrane & cytoskeletal proteins
 cholesterol:phospholipid ratio ↑es
 lens capsule- thickens throughout life (collagen type IV vs. I, III,
IV)

16. LENS:…
 Physiological Changes:
 Changes to the cellular junctions and alteration on cation
permeability
 membrane potential- from –50mV (at age of 20 yrs) to –20mV (at
the age of 80 yrs)

17. • sodium concentration - ↑es
• Na+
:K+
permeability ratio ↑es by six fold
• free calcium level ↑es Ca ATPase inhibited

18. LENS:…
• Biophysical Changes:
• UV & visible light absorption ↑es
• ↑ 3-hydroxykynurenine glucoside
(3-HKG)
• ↑ yellow-pigmented proteins
• ↑ fluorophores

19. • thus transmission of visible light & lens transparency ↓es
• the amount of light reaching the retina in a normal 60-
year-old is only about 1/3rd
that reaching the retina of a 20-
year old
• amplitude of accommodation ↓es

20. LENS:…
• Biochemical Changes:
• overall metabolic activity of the lens ↓es
• ↓ glycolytic activity
• ↓ level / activity of antioxidants

21. • Changes in Crystallins:
• accumulation of high molecular weight aggregates
• some act as scatter points for light
• ↑ed insolubility

22. • Exaggeration of normal nuclear
ageing change
• Causes increasing myopia
• Increasing nuclear opacification
• Initially yellow then brown

23. VITREOUS:
 index of refraction of the vitreous
increases ( hypermetropia)↑
 syneresis of the vitreous
 Increased vitreous floaters
 Decreased support to the posterior
lens surface

24. RETINA AND NEURAL CONNECTIONS:
in the absence of pathology, only little decline in static
visual acuity with age that can not be accounted for by
miosis and increased density of the lens
pathologies that are the major cause of decline in static
visual acuity are cataract, macular degeneration and
glaucoma

25. • mesopia occurs at higher levels of ambient illuminace
in older people
• The arteries and veins of the retina become narrower
with age, reducing the flow of blood.

26. The ageing retina is duller and exhibits a less
responsive light reflex.
The optic disk may be paler also.
 This creates a need for more light in order to read or
accomplish other tasks.

27. SENILE MACULAR
DEGERATION
• Warning signs may include:
• gradual, spotty loss of detail vision
(dry macular degeneration);
• sudden and severe loss of central
vision (wet macular degeneration);
• a need for more light.

28. RETINA AND NEURAL CONNECTIONS:…
• ↓ contrast sensitivity due to increased lens
fluorescence and light scatter
• with shift of peak sensitivity to lower frequencies
• ↓ in the ability to discriminate colours

29. • ↓ visual field size and sensitivity
• absolute level of dark adaptation reached by the elderly is
less than that reached by younger individuals

30. REFRACTIVE STATUS:
• static power of the eye: hypermetropic shift
• cornea: ↑ against-the-rule astigmatism
• anterior chamber: ↑ myopia
• lens: hypermetropia or myopia
• vitreous: ↑ hypermetropia

31. OCULAR MOTOR SYSTEM:
 under scotopic conditions, aging people have difficulty
with fixation
 ↑ exotropia with age
 the range of voluntary eye movements becomes limited
 supraduction ↓es with age
 ↑ tonic vergence with distance heterophoria (esophoria)

32. ↓ positive fusional vergence but same negative
fusional vergence
↓ accommodation with ↑ AC/A ratio & ↓ CA/C
↓ stereopsis

33. OTHER CHANGES WITH AGING:
• ↓ aqueous secretion
• ↓ resistance to distraction
• ↓ ability to selectively attend to one source of
information in the presence of competing
messages

34.  ↓ ability to separate visual events that happen serially declines
with age
 ↓ dynamic visual acuity (VA for moving targets)
 related to ↓ in the rate of smooth following eye movements
 ↑ variability in visual performance between individuals