Eye Disorders that can occur at work.

1. BY:
RABIA AMMER
GOLD MEDALIST
OCCUPATIONAL
EYE DISORDERS

2. IMPORTANT
Usa:1.4 Million Injury &Illness In 2002
- 47% Of All Head Injury
- Ocular Foreign Body:38%
- Contusion/Abrasion:27%
- Burn:12%
- Conjectivitis:11%
Non-construction>welder>cutter>truck
driver

3. TWO GENERAL TYPES OF VISION AND
EYE ASSESSMENTS CAN BE
DIFFERENTIATED
 Examination
— Examines subjects for
eye
disorders and diseases
— Diagnoses eye
disorders
and diseases
— Prescribes treatment
 Screening
— Identifies those at high risk
or in need of a professional
examination
— May detect disorders in
early, treatable stage
— Provides public with
valuable information and
education about eye care
— Results in referral to an eye
care professional or primary
care provider

4. COMPONENTS OF VISION SCREENING
History and symptoms
Visual acuity at any distance
Visual field
Colour vision
Depth perception
Contrast sensitivity

5. VISUAL ACUITY
Snellen chart
Acuity at
Near&Distance

6. VISUAL FIELD
Confrontation test
primetry

7. COLOUR VISION TEST
Ishihara
plates

8. CLINICAL TESTS FOR STEREOPSIS
Contour stereotest
 Titmus stereotest
Random dot stereotest
 Frisby test
 Random Dot-E test

9. CLINICAL CONTRAST SENSITIVITY TESTS
 Pelli-Robson chart
 Regan low-contrast

10. CARE WITHOUT SCARE…!
OCCUPATIONAL HEALTH FOR
HEALTH CARE WORKERS

11. OCCUPATIONAL HEALTH
PHYSICAL, MENTAL & SOCIAL WELL
BEING IN RELATION TO WORK AND
WORK ENVIRONMENT.

12. WHAT IS OCCUPATIONAL HEALTH?
Occupation (work) Health
Accidents
Environment
Different Definitions:
Health problems arising from or pertaining to work
Health of people at work
The Health of the gainfully employed
Relationship between Occupation (work) & Health

13.  Occupational diseases have a long latent
period.
 Most occupational diseases cannot be
treated.
 All occupational diseases can be
prevented.
Occupational Diseases

14. What the mind
does not know,
the eyes do not
see

15. OCCUPATIONAL HAZARDS
 Physical Hazards
 Chemical Hazards
 Biological Hazards
 Mechanical Hazards
 Psychosocial Hazards

16. FOUR TYPES
Diseases only occupational in origin
Where occupation as one of the causal factors
Occupation as A contributary factor
Occupation aggrevating pre-existing condition

17. OCCUPATIONAL EYE
ILLNESS
 EYE INJURIES
 EYE DISEASES

18. EYE CHEMICAL BURNS
1. Alkali burns
2. Acid burns
3. Irritants

19. EYE ACID BURNS
Sulfuric acid
Nitric acid
Chlorohydric acid
Hipochloric acid
Perchloric acid
Flurohydric acid
Cholor
So2 , So3

20. ALKALI BURNS
Sodium hydroxide
Potassium hydroxide
Amonia
Cement
Lye
Detergents

21. EMERGENCY
 Treatment should be immediate, even before
making vision tests!
 Premedicate with proparacaine or tetracaine.
 Copious irrigation: LR or NS X 30 min.
 Wait 5 minutes and check pH. If not normal,
repeat.

22. MILD-TO-MODERATE CHEMICAL
BURNS
Critical signs
Corneal epithelial
defects range from
scattered
superficial punctate
keratitis (SPK) to
focal epithelial loss
to sloughing of the
entire epithelium

23. MILD-TO-MODERATE CHEMICAL
BURNS
Other Signs:
Focal area of
conjunctival
chemosis.
Hyperemia.
Mild eyelid edema.
Mild-anterior
chamber reaction.
1st
or 2nd
degree burns
to periocular skin.

24. MODERATE-TO-SEVERE CHEMICAL
BURNS
 Critical signs:
 Pronounced
chemosis and
perilimbal
blanching
 Corneal edema
and opacification

25. MODERATE-TO-SEVERE CHEMICAL BURNS
 Other signs:
 Increased IOC
 2nd
& 3rd
degree burns of
the surrounding tissue
 Local necrotic
retinopathy

26. TREATMENT :
Irrigation
Antibiotics
Artificial tear
Steroids
Ascorbic acid
Calcium gluconate
dilating eye drop

27. COMPLICATIONS :
Scares
Glaucoma
Blindness

28. PHYSICAL TRAUMA
 Corneal abrasionCorneal abrasion
 Corneal lacerationCorneal laceration
 Foreign BodyForeign Body
Illinois EMSC28

29. CORNEAL FOREIGN BODY
 Symptoms:
 Foreign-body sensation
 Tearing
 Blurred vision
 Photophobia
 Commonly, a history of
a foreign body

30. PENETRATING OCULAR INJURY
 Incidence : 1.4%-4%
 Industries at Greatest risk: construction; manufacturing
 Object: metal fragment ;glass; nail
 Sign:
 Flat eye
 Low vision
 Low intraocular pressure
 hyphema

31. RADIATION :
UV < 400 nm
IR > 700 nm
Visible 400 – 700 nm
Ionising <0.0001 nm
ELF 1000 - 10000 Km

32. ELECTROMAGNETIC
SPECTRUM
Radio Micro I.R. Visible U.V. X-ray
γ-ray
104
106
1010
1013
1023
Hz

35. UV SOURCES :
Sun
Welding
Lamps
Foundry
Blacksmitch
 UV-C:100-290nm:does not normally penetrate
the earth atomospher
 UV-B:290-320 nm: cortical cataract;
petrygium; photokeratit; intraocular
melanoma??
 UV-A:320-400nm: petrygium

37. INFRA RED
IR - A : 780 – 1400 nm
IR – B : 1400 – 3000 nm
IR – C : 3000 - 10000 nm
All form of cataract
Pathagnomonic: exfoliative or
splitting of anterior lens capsule

38. IR SOURCES :
Sun
Heaters
Steel Industry
Glass Industry
Lasers YAG - Neodymium - CO2
Lamps
Welding

39. IR ABSORPTION IN EYE :
Cornea : IR-C IR-B
Lens : IR-A
Retina : IR-A
As shorter wave length more heat
production

41. CAUSES OF OCCUPATIONAL
CATARACTS :
 microwaves,
 TNT
 , ionizing radiation
 , infrared radiation,
naphthalene,
dinitrophenol,
 dinitrol-o-cresol,
 ethylene oxide.
 Intense exposure to UV light
in the 295-320 nm range can
cause cataracts that usually
appear within 24 h
 "X-ray radiation in a dose of
500-800 R directed toward the
lens surface can cause
cataracts,

42. LASER EYE DAMAGE

43. http://www.adm.uwaterloo.ca/infohs/lasermanual/documents/section11.html
The majority of injuries involve the eye and, to a
lesser extent, the skin
Summary of reported laser accidents in the United States and their causes
from 1964 to 1992

44. EXPOSURE LIMITS – LASER
CLASSIFICATION
Class 1 Lasers
Class 1 lasers do not emit harmful levels of
radiation .
Class 2 Lasers
Capable of creating eye damage through chronic
exposure. In general, the human eye will blink
within 0.25 second when exposed to Class 2 laser
light, providing adequate protection. It is
possible to stare into a Class 2 laser long enough
to cause damage to the eye.
At LCVU we use almost exclusively Class 3 and Class 4 lasers!

45. Class 3a Lasers (1-5 mW)
Not hazardous when viewed momentarily with the naked eye, but
they pose severe eye hazards when viewed through optical
instruments (e.g., microscopes and binoculars).
Class 3b Lasers (5-500 mW )
Injury upon direct viewing of the beam and specular reflections.
Specific control measures must be implemented.
Class 4 Lasers (> 500 mW )
They pose eye hazards, skin hazards, and fire hazards. Viewing of
the beam and of specular reflections or exposure to diffuse
reflections can cause eye and skin injuries. All control measures to
be outlined must be implemented.
EXPOSURE LIMITS – LASER
CLASSIFICATION

46. THE EFFECTS OF THE LASER
DEPENDS STRONGLY ON THE
WAVELENGTH
http://www.adtdl.army.mil/cgi-bin/atdl.dll/fm/8-50/INTRO.htm

47. The biological damage caused by lasers is produced
through thermal, acoustical and photochemical
processes.
Thermal effects are caused by a rise in temperature
following absorption of laser energy. The severity of the
damage is dependent upon several factors, including
exposure duration, wavelength of the beam, energy of
the beam, and the area and type of tissue exposed to the
beam.
The most likely effect of intercepting a laser beam with
the eye is a thermal burn which destroys the retinal
tissue. Since retinal tissue does not regenerate, the
damage is permanent.
POTENTIAL EYE DAMAGE

48. Acoustical effects result when laser pulses
with a duration less than 10 microseconds
induce a shock wave in the retinal tissue
which causes a rupture of the tissue. This
damage is permanent, as with a retinal burn.
Acoustic damage is actually more
destructive than a thermal burn. Acoustic
damage usually affects a greater area of the
retina, and the threshold energy for this
effect is substantially lower.
POTENTIAL EYE DAMAGE

49. Beam exposure may also cause
Photochemical effects when photons interact
with tissue cells. A change in cell chemistry
may result in damage or change to tissue.
Photochemical effects depend strongly on
wavelength.
the severity of the eye damage depends
strongly on whether it occurs by intrabeam
exposure or scattered laser light
POTENTIAL EYE DAMAGE

50. http://www.adtdl.army.mil/cgi-bin/atdl.dll/fm/8-50/INTRO.htm
EXAMPLE OF EYE DAMAGE
Experience has demonstrated that most
laser injuries go unreported for 24–48
hours by the injured person. This is a
critical time for treatment of the injury.