3. Contents
▪ Introduction and definition of preventive
ophthalmology
▪ Servicing based on groups.
▪ Early age screening : Amblyopia , strabismus ,
congenital cataract , retinopathy of prematurity
▪ Preventive ophthalmology in ocular injuries
▪ Visual impairment in Adult : Refractive error,
Glaucoma,AMD, Blindness and low vision
▪ Preventive Ophthalmological Projects inThailand
4. Preventive Ophthalmology
▪ Public health ophthalmology / Preventive eye
care/ Community ophthalmology
▪ To provide an ophthalmologic service;
identifying and preventing eye sight
threatening ocular condition, to whoever
(mass, large number) in community in
affordable costs.
6. Primary prevention
▪ To prevent people from disease.
▪ Eliminate or limit the risk factors and pathogen
exposure.
Methods
Community immunization : การสร้างเสริมสุขอนามัย การสร้างสุขนิสัยที่ดี
การดูแลเรื่องโภชนาการ การให้ภูมิคุ้มกัน หรือยา ป้องกันโรค ตลอดถึงการควบคุมทาง
พันธุกรรม
Environmental control : งานด้านสุขาภิบาล การกาจัดพาหะนาโรค การดูแลอาชี
วอนามัย และการจัดการเรื่องสิ่งแวดล้อม
Health care system management : ให้สุขศึกษา ความรู้พื้นฐาน การ
ดูแลรักษาเบื้องต้น การออกกฎหมาย และการจัดระบบบริการต่างๆ
7. Primary prevention
▪ การควบคุมภาวะขาดวิตามินเอ (Vitamin A deficiency)
▪ การควบคุมโรคริดสีดวงตา (Trachoma)
▪ การควบคุมการติดเชื้อที่กระจกตาในเด็กอ่อน (Infected cornea)
▪ การบริการด้านอาชีวอนามัย (Occupational health service)
8. Secondary prevention
▪ To prevent disease’s progression and disability
▪ Early diagnosis
Screening may not efficient and value in every diseases.
We consider to do in case of…
High severity
High incidence and prevalence
High understanding of pathogenesis
There’re effective treatments available
Screening tool is accurate, accountable and affordable.
10. Tertiary prevention
▪ To rehabilitation, correction of disability
Examples :
Blindness rehabilitation
Keratoplasty
11. Servicing based on groups
▪ Child (<6 year-old) with low risk
▪ Child with high risk
▪ Adult with low risk
▪ Adult with high risk
12. Child with low risk
▪ Ocular examination should be done once the infant born,
6 months , 3 years and at 5-6 years
Once they born : external eye examination, ocular
alignment (Hirschberg’s test), ophthalmoscopy
6 months :VA, Ext eye examination, pupillary exam,
ocular alignment, ophthalmoscope (Red reflex)
3 years :VA (Picture,E game), Ext eye examination,
pupillary exam, ocular motility and alignment,
ophthalmoscope (Red reflex)
5-6 years :VA (Snellen), Ext eye examination, pupillary
exam, ocular motility and alignment, ophthalmoscope
(Red reflex and fundus)
13. Child with high risk
▪ Refer to ophthalmologist
▪ Defining high risk…
Preterm
Family history of cataract, retinoblastoma,
strabismus or amblyopia
Systemic disease
14. Adult with low risk
6-40 year-olds :VA q 3 year
> 40 year-olds : refer to ophthalmologist q 2-4 year
for presbyopia and glaucoma screening
15. Adult with high risk
▪ Refer to ophthalmologist q 1-2 years
▪ Defining high risk…
Hx of Retinal detachment/Severe ocular trauma
Low vision
Underlying disease : DM, HT
Family Hx of Glaucoma, eye disease
Over 65 year-olds
16. Amblyopia & Strabismus
▪ Primary prevention
– Screening for causes of from deprivation within the first
4-6 weeks after birth, and children at risk should be
monitored yearly to 4 years of age
Newborn to 3 months of age
– Red reflex test with a direct ophthalmoscope.
– External inspection of the eyes to assess for any structural
abnormalities (penlight exam is sufficient).
– Pupillary exam.
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17. Amblyopia & Strabismus
3-6 months of age
– Tests for newborn to 3 months are repeated.
– Tests to check whether the infant can fix and follow with each
eye independently.
6-12 months of age, and then yearly until
the child can co-operate with verbal visual
acuity testing
– Tests for newborn to 3 months are repeated.
– Corneal light reflex test, to check for a symmetrical response in
both eyes.
– Alternate occlusion of each eye: the infant's behavioral response
should be equal to having either eye occluded. In other words,
the infant should object or not object equally.
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18. Amblyopia & Strabismus
3-4 years of age
– Tests for newborn to 3 months are repeated.
– Corneal light reflex test, to check for a
symmetrical response in both eyes.
– Cover/uncover test to assess for re-fixation
movements.
– Visual acuity testing, independently for each
eye.Visual acuity of 20/50 or worse, or a ≥2 line
difference between the 2 eyes, should be
referred.
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19. Amblyopia & Strabismus
5 years of age
– Tests for newborn to 3 months are repeated.
– Corneal light reflex test, to check for a
symmetrical response in both eyes.
– Cover/uncover test to assess for re-fixation
movements.
– Visual acuity testing, independently for each
eye.Visual acuity of 20/40 or worse, or a ≥2 line
difference between the 2 eyes, should be
referred.
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20. Amblyopia & Strabismus
▪ Secondary prevention
The American Academy of Ophthalmology
recommends that patients who are functionally
monocular due to amblyopia should help to prevent vision
loss to the better-seeing eye by
– Wearing polycarbonate spectacles even if they do
not require refractive correction
– Wearing protective goggles and facial protection for
contact sports and potentially dangerous activities
such as paintball
– Having regular eye examinations throughout life.
Reference: Bestpractice(BMJ group): Amblyopia
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21. Amblyopia & Strabismus
▪ Tertiary prevention
– Follow up at 2, 4, 6, 8 and 12 months are recommended
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22. Congenital cataract
▪ A congenital cataract is a clouding of the lens of the
eye that is present at birth.
Risk factors
–Genetic disease, birth defect
–Intrauterine infections : maternal
rubella
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24. Retinopathy of prematurity
▪ Retinopathy of prematurity (ROP) is a disease
that affects immature vasculature in the eyes of
premature babies. It can be mild with no visual
defects, or it may become aggressive with new
blood vessel formation (neovascularization) and
progress to retinal detachment and blindness
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26. Retinopathy of prematurity
▪ Primary prevention
– Quality antenatal care to prevent premature birth
– Quality neonatal care: well-maintained and working
incubators
▪ Secondary prevention
– Screening (Age 4-6 wks)
1. Prematurity ( GA<32 wks)
2. LBW<1500 gm
3. GA>32 wks and BW 1500-2000 gm with unstable clinical
cause
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27. Retinopathy of prematurity
▪ Tertiary prevention
– Cryotherapy or lacer photocoagulation at stage
III will prevent progression of disease to retinal
detachment.
– Follow up for complication such as vitreous
hemorrhage, retinal detachment.
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29. Occupational ocular injuries
▪ Chemical Burns
– One of the two “true” ocular emergencies.
– Chemical burns to one or both eyes from splashes of
industrial chemicals or cleaning products are common.
– Acid vs Alkali
30. Occupational ocular injuries
▪ Radiation Burns
UV radiation burns (welder’s flash) routinely
damage workers’ eyes and surrounding tissue,
leading to epithelial keratitis.
31. ▪ Who are at risk?
– Patients who work in physically-demanding jobs, including
factory workers, manufacturers, welders, carpenters, and
construction workers.
▪ Prevention
– Proper training and education of workers in the use of
machinery and goggles, as well as the public.
– Early recognition & urgent assessment of ocular injuries
are essential.
– Proper labeling and storage
Occupational ocular injuries
32. Non-occupational ocular
injuries
▪ Ultraviolet radiation exposure
– Associated with pterygium, basal cell carcinoma
and melanoma of the eyelids
– Substantial evidence linking UV exposure with
development of cataract.
▪ Prevention
– Wear Protective Eyewear such as sunglasses.
34. Refractive error
▪ Refractive error
– Myopia, Hyperopia, Astigmatism
– Risk factor
▪ Family history
▪ Previous history of ocular trauma, surgery, infection
▪ Near-work
▪ Primary prevention
– Avoid risk factor
▪ Secondary prevention
– Optical correction
▪ Spectacle
▪ Lens
▪ Refractive surgery
▪ Tertiary prevention
– Prevent amblyopia by Optical correction
35. Glaucoma
▪ Risk factor
– Age>40 years
– Asian
– Family history
– Refractive error
– Steroid
▪ Primary prevention
– Avoid Risk factor
36. ▪ Secondary prevention
– Early detection
▪ Age 40-60 : test every 4 years
▪ Test every 1-2 year if
– Age 60 or more
– Family history of glaucoma
– Asian or black
– DM, Chronic inflammatory disease
– History of eye injury
– Using steroid
▪ Tertiary Prevention
– Surgery :Laser Iridotomy
Glaucoma
37. Age related macular
degeneration
▪ More than 50 years
▪ Loss of central field of vision
▪ Macula degenerative lesion
▪ The primary cause of visual impairment in
industrialized countries.
▪ Primary prevention
– Avoid risk factor
▪ Use of tobacco
▪ Genetics tendencies
▪ Arterial hypertension
▪ UV
38. ▪ Secondary prevention andTertiary prevention
– Laser
– Surgery
– Rehabilitation
– Bright lighting
– Use special aids for viewing or using computer
Age related macular
degeneration
40. Blindness
▪ Definition
– The inability to see
▪ The World Health Organization (WHO)
– best corrected visual acuity of 3/60 or less, in the better
eye
42. Vision
▪ The sense by which objects in the external
environment are perceived by means of the light
they give off or reflect.
▪ The act of seeing.
43. Low vision
▪ The World Health Organization (WHO)
Visual acuity less than 6/18 and equal to or better
than 3/60 (10/200) in the better eye with best
correction
46. Global Prevalence of Visual
Impairment
▪ Vision 285 million people are estimated to be visually
impaired worldwide: 39 million are blind and 246 have low
vision.
▪ About 90% of the world's visually impaired live in developing
countries.
▪ 82% of people living with blindness are aged 50 and above.
▪ Globally, uncorrected refractive errors are the main cause of
visual impairment; cataracts remain the leading cause of
blindness in middle- and low-income countries.
▪ The number of people visually impaired from infectious
diseases has greatly reduced in the last 20 years.
▪ 80% of all visual impairment can be avoided or cured.
47. Number of people (in thousands) blind,
with low vision and visually impaired
per million population
50. ▪ As a global target, the reduction in prevalence of
avoidable visual impairment by 25% by 2019 from the
▪ baseline of 2010 has been selected for this action plan
▪ The reduction in the prevalence of avoidable visual
impairment in that portion of the population representing
those who are over the age of 50 years, cataract and
uncorrected refractive errors are the two principal causes
of avoidable visual impairment, representing 75% of all
visual impairment.
52. Estimated weighted prevalence of
Blindness by regions, 2006
0
0.5
1
1.5
2
2.5
3
Bangkok Central East West Northeast South North
Blindness one eye
Blindness both eyes
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65. Prevention and treatment of
Cataract
▪ Primary Prevention
- Have regular eye examinations
- Quit smoking
- Reduce alcohol use
- Wear sunglasses
- Manage other health problems
- Maintain a healthy weight
- Choose a healthy diet that includes plenty of fruits and
vegetables
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66. Prevention and treatment of
Cataract
▪ Secondary prevention
- Early diagnosis and treatment
▪ Tertiary prevention
- Surgery
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67. Prevention and treatment
of Diabetic retinopathy
▪ Primary prevention
- Diminish risk factor :
Weight , Inactivity , High blood pressure , Abnormal cholesterol levels , High
levels of triglycerides
- Control stage of those risk
- Screening for DM
Age > 40
FH of DM
Pregnancy
Hypertension
Dyslipidemia
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68. Prevention and treatment
of Diabetic retinopathy
▪ Secondary prevention
- Eye examination for early diagnosis
- Glycemic control ( HbA1C < 7% )
- Blood pressure contral ( BP < 130/80 )
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