Causes of low vision in adult

1. CAUSES OF LOW VISION
IN ADULTS
Presenter:-Harshali Jadhav
Moderator :-KUNAL KISHOR

2. Definition
Low vision:- According to WHO
A person with low vision is are who has
impairment of visual function even after
treatment and/or standard refractive correction
and has an a acuity of less than 6/18 to light
perception or visual field less than 10* from the
point of fixation, but who uses or its potentially
able to use vision for the planning execution of
the task.

3. Introduction
The number of with low vision is increasing with
ageing of the population
Visual loss in adult is associated with many factors,
activity, limitation and lower quality of life

4. CAUSES OF
LOW VISION IN
ADULT

5. AGE RELATED MACULAR DEGENERATION
It is an acquired retinal disorder
A degenerative change in retinal pigmented
epithelium

6. Subsequent degeneration of the over line rods and
cones
It results in progressive irreversible loss of central
vision
Due to fibrous scarring or geographic atrophy of the
macular area

7. Risk Factors …
Hyperopic
Increase in cup disc ratio
Elevated serum cholesterol & hypertension
Smoking and sunlight exposure

8. VISUAL ACUITY :-
V/A May vary with extent of degeneration with dry
state ARMD
V/A can range from 20/20 to 20/400
Wet state ARMD V/A shows worse than 20/400
VISUAL FIELD:-
Demonstrate a central or Para central Scotoma with
normal peripheral findings

9. Most patient response well to magnification at
distance and near
Non-optical systems filters, tint , and sun lenses for
improve contrast and avoided glare and photophobia

10. CATARACT
It’s the opacification of crystaline lens
The types includes anterior and posterior subcapsular
, cortical, equatorial and nuclear

11. ETIOLOGY:-
Traumatic
Metabolic
Toxic
Pharmacological
Age related
Inflammatory
Hereditory

12. VISUAL ACUITY:-
V/A varies greatly dividing on the degree and location
of opacification
Acuity range from normal to severe vision
impairment
VISUAL FIELD:-
Central and peripheral visual field testing generally
source a relative generalize depression without focal
defects

13. LOW VISION MANAGEMENT:-
Direct lighting is generally for near point
activities
Glare can be reduce by use of Filters tint and sun
lenses
Patients response to magnification at distance
and near which may postpond the need of cataract
surgery

14. Non-optical system such as large print reading
material, bold line writing paper , typo scope .

15. DIABETIC RETINOPATHY
It’s a highly specific vascular complication
Independent Diabetic mellitus and Non -
Independent Diabetic Meliates
It is one of the leading cause of blindness

16. VISUAL ACUITY:-
V/A ranges from 20/20 to total blindness
VISUAL FIELD:-
In profilative disease retinal schemic loser scar and
retinal detachment can cause corresponding field loss

17. LOW VISION MANAGEMENT:-
Refractive error should be checked during at least to
different visits
Use of contact lens to correct refractive error
Corning photochromatic filter and sunlens that block
blue wavelength may improve contrast and eliminate
glare and photophobia

18. Direct illumination for near task
A flash light is helpful for poor night vision patient

19. Eccentric viewing technique along with magnification
for distance and near
Non-optical device such as glucose monitor and
insulin syringe aid are helpful for the patient.

20. MULTIPLE SCLEROSIS
It is demilinating nerve fibers have on impaired
ability to conduct impulses at
physiological frequencies

21. VISUAL ACUITY:-
V/A ranges from normal to severely impaired
depending on the extend of ocular manifestation
VISUAL FIELD:-
Several pattern of visual field loss occurs of patients
with optic neuritis secondary to multiple sclerosis
Central and ceco-central scotomas may be present

22. LOW VISION MANAGEMENT:-
Magnification device for near and distance are
beneficial for patient with central vision loss
Spectacle mounted device
Corning photo chromatic filter, Tints and sunglasses
help to eliminate glare
Non-optical device such as direct lighting

23. MYOPIC DEGENERATION
It occurs due to accessive stretching of posterior
segment of the eye
It associated with increasing axial length

24. VISUAL ACUITY:-
V/A may be corrected by 20/20
High myopia can results in variety of visual field
defect
In more advanced state sub-retinal neo-vascular
membrane formation may occur causing further in
decrease in central acuity

25. LOW VISION MANAGEMENT:-
Optical correction of refractive error with
conventional spectacles or contact lenses usually
improve V/A
Direct illumination for near

26. Cont……..
When using spectacle lenses a small round frame,
high index lenses and anti reflection coating will help
to reduce peripheral distortion
For poor night vision flashlight is helpful

27. RETINAL DETACHMENT
It results from accumulation of fluid between the
sensory retina and retinal pigment membrane

28. VISUAL ACUITY:-
V/A can be severely reduced , if there is involvement
of macular area
VISUAL FIELD :-
Field defect develops corresponding to the sight of
retina detachment

29. LOW VISION MANAGEMENT:-
Using sunglasses and tint can be eliminate glare and
photophobia
Direct illumination for near point task
Due to affected central vision a new correction may
be indicated

30. Cont………
If bilateral temporal detachment occurs presence may
be considered for improve mobility along with
orientation and mobility services

31. GLAUCOMA
It is an optic neuropathy cause by reduce blood flow
to the optic nerve resulting in peripheral visual field
loss progressing to central vision loss with severe

32. ETIOLOGY
Family history
Advanced age
Systemic vascular disease
Blunt ocular trauma
Pigment dispersion
Psuedo-exploxation
Rubio sis iriditis
Use of steroid drugs
Glaucoma in fellow eye

33. VISUAL ACUITY
Central v/a is generally un affected until the end stage
of disease
VISUAL FIELD
Early glaucomatous visual field defects includes Para
central Scotoma , nasal field loss from this area occur
as disease worse

34. LOW VISION MANAGEMENT:-
 Electronic Magnification system such as closed circuit
television ( C.C.TV) increased contrast and brightness
 Corning photo chromatic filter may reducing glare
and improving contrast

35. Minus lenses and reversible telescope helps the
Patient with intact central acuity and peripheral visual
field loss

36. To enhance visual field
Prisms or mirror system may stimulate peripheral
awareness
Create Orientation and mobility in end stage visual
field loss of galucoma patient
 long cane travel can beneficial in end stage disease
Use of flash light in night travel

37. THANK YOU…