Retinopathy of prematurity (ROP), initially described as retrolental fibroplasia one of the leading cause of blindness in children. Despite advances in diagnosis and treatment, as medicine and technology advances and premature infants are surviving at earlier gestational ages, ROP continues to be a significant problem. ROP results in disorganized growth of retinal blood vessels, which may lead to scarring and retinal detachment.

1. Retinopathy of Prematurity
Dr RS Walpitagamage
Registrar in Ophthalmology
TH Kandy
Sri Lanka

2. Disease Entity
• Retinopathy of prematurity (ROP), initially described as retrolental
fibroplasia one of the leading cause of blindness in children.
• Despite advances in diagnosis and treatment, as medicine and
technology advances and premature infants are surviving at earlier
gestational ages, ROP continues to be a significant problem.
• ROP results in disorganized growth of retinal blood vessels, which
may lead to scarring and retinal detachment.

3. Etiology
• ROP occurs in premature infants who are born before the retinal
vessels complete their normal growth.
• Local ischemia plays a role, just as in other proliferative retinopathies
like diabetic retinopathy and sickle cell retinopathy.
• Its incidence varies inversely with birth weight and gestational age.
• Oxygen has long been known to have a role in the disease process.
• Excessive oxygen can cause vaso-obliteration in the immature retina.
• Studies have shown that keeping the oxygen saturation at a lower
level from birth can reduce the rate of advanced ROP

4. PATHOPHYSIOLOGY

5. Pathophysiology
• In utero, the fetus is in a hypoxic state in contrast to after birth.
• When infants are born prematurely, the growth of retinal vessels is
stimulated by vascular endothelial growth factor (VEGF).
• However if the immature retina is exposed to ongoing hyperoxia, the
vessels will stop growing.
• Over time, the avascular retina becomes ischemic and stimulates
VEGF in some cases leading to arterial venous shunts and
neovascularization.

6. Risk Factors
Key risk factors
• Low birthweight (less than 1500 grams)
• Gestational age (32 weeks or less)
• Extended supplemental oxygen, although the exact role is not fully
understood
Suggested risk factors
• Intraventricular hemorrhage, respiratory distress syndrome, sepsis,
white race, and multiple births.

7. Primary prevention
• Screenings of infants at risk with appropriate timing of
exams and follow up is essential in identifying infants
in need of treatment

8. Recommended Timing of First Exam Based on
Gestational Age
Gestational Age at Birth Postmenstrual (weeks) Chronologic (weeks)
23 weeks 31 8
24 weeks 31 7
25 weeks 31 6
26 weeks 31 5
27 weeks 31 4
28 weeks 32 4
29 weeks 33 4
30 weeks 34 4
31 weeks 35 4
32 weeks 36 4

9. Diagnostic procedures
• Following pupillary dilation using eye
drops, the retina is examined using an
indirect ophthalmoscope. The peripheral
portions of the retina are pushed into
view using scleral depression

10. Zones depict
the location
of the
disease in
the retina

11. The International Classification of ROP
(ICROP) includes 5 parameters
(1) Zone: The location of the disease in the retina
• Zone I is the posterior retina within 60 degrees of the optic disc
• Zone II is a concentric circle extending from Zone 1 to the nasal ora serrata
• Zone III is the remaining temporal retina
(2) Clock hours: The extent of the developing vasculature that is involved quantified from 1-12 clock hours
(3) Stage: The severity of the abnormal vascular changes observed
• Stage 1: Demarcation line between vascularized and non-vascularized retina
• Stage 2: Demarcation line w/ elevation
• Stage 3: Demarcation line with fibrovascular proliferation
• Stage 4a: Partial detachment of retina not involving fovea
• Stage 4b: Partial detachment of retina involving fovea
• Stage 5: Total retinal detachment
(4) Plus disease: Venular dilation and arteriolar tortuosity in the posterior pole
(5) Pre-plus disease Abnormal-appearing vasculature that does not make criteria for Plus disease

12. ROP, Stage 1.
Demarcation
line between
vascularized
and vascular
retina

13. ROP, Stage 2

14. ROP, Stage 3.
Extraertinal
fibrovascular
proliferation.

15. ROP, Stage 4a.
Partial
detachment of
the retina not
involving the
fovea.

16. ROP, Stage 4b.
Partial
detachment of
the retina
involving the
fovea.

17. ROP, Stage 5.
Total retinal
detachment.

18. Pre-plus disease.
Abnormal-
appearing
vasculature that
does not meet
criteria for Plus
disease.

19. Management
• Ophthalmologists with adequate knowledge of ROP should perform retinal exams in
preterm infants.
• The initial exam should be based on the infant’s age .
• Follow up recommendations were updated in 2006 by the American Academy of Pediatrics
and depend on the location and stage.
• Follow up of 1 week or less:
Stage 1 or 2 ROP in zone I
Stage 3 ROP in zone II
• Follow up of 1 to 2-weeks:
Stage 2 ROP in zone II
Regressing ROP in zone I
Immature vessels in zone I

20. Follow up
• Follow up of 2-weeks:
Stage 1 ROP in Zone II
Regressing ROP in zone II
• Follow up of 2 to 3-weeks:
Immature vessels in zone II
Stage 1 or 2 in zone III
Regressing ROP in zone III

21. TREATMENT
• Treatment is based on 2 multicenter trials: the Cryotherapy for Retinopathy
of Prematurity (CRYO-ROP) trial and the Early Treatment for Retinopathy of
Prematurity (ETROP) trial (CRYO-ROP Cooperative Group, 1988 and ETROP
Cooperative Group, 2008)
• Laser photocoagulation is the preferred treatment of choice. If laser is not
available, cryotherapy may be performed.
• Laser photocoagulation is performed when ROP reaches type 1 pre-
threshold disease.
• It is important to diagnose aggressive posterior ROP (AP-ROP) and treat it
immediately, as this form of ROP can rapidly progress to retinal
detachment.
• Intravitreal injections of anti-vascular endothelial growth factor (Anti-
VEGF) may cause rapid resolution of AP-ROP (Mintz-Hittner et al., 2011).
However, laser photocoagulation remains the standard of care for most
cases of treatment requiring ROP.

22. Surgery
• If laser or cryotherapy fails to prevent progression of ROP and the
patient develops a retinal detachment, surgery (vitrectomy, scleral
buckle) may be performed.
• Results are best when done before the fovea has detached.
• Stage 5 ROP has a poor visual prognosis

23. Complications
• The most feared complication in ROP is retinal detachment or
macular folds.
• There are a number of other complications related to this disease
that can effect visual development.
• Myopia is a common finding in premature infants with our without
ROP.
• Infants with regressed ROP also have an increased incidence of
strabismus, amblyopia, and anisometropia.

24. REFERENCES
• https://eyewiki.aao.org/Retinopathy_of_Prematurity
• https://www.aao.org/topic-detail/retinopathy-of-prematurity--asia-
pacific#figure7

25. Thank you
https://www.slideshare.net
/RasikaWalpitagamage