Retinopathy of Prematurity

1. Retinopathy of Prematurity
Nilufa Akter
Optometrist (B.Optom, ICO, CMU)
Ispahani Islamia Eye Institute and Hospital

2. Retinopathy of Prematurity
• Is a bilateral abnormal proliferation of the retinal
blood vessels in eyes of newborn infants in whom
retinal vascularization is incomplete.

3. Incidence
• Overall incidence: 16-17% for all premature
infants
• 68% ROP in BW <1250gm
• 98% among those having BW <750gm

4. Risk Factors of ROP
 3 Crucial risk factors:
-Low gestational age <32 wks
-Low Birth weight (<1500gm)
-Supplemental O2 therapy
 Other risk factors:
-Multiple child birth
-Respiratory Distress Syndrome (RDS)
-Blood transfusions
-Fluctuation in SaO2
-Intra Uterine Growth Retardation (IUGR)
-Multiple apneic episodes
-Hypercarbia, Acidosis
- Intra Ventricular Hge (IVH)
-Vit E deficiency
-Anemia
-Seizures

5. Embryology of Retinal Blood Vessels

6. Pathogenesis of ROP
Prematurity
Incomplete retinal vascularization
When exposure to increased O2
Immature vessels may be occluded (Vasoconstriction) by high O2
concentration
Formation of Ischemic retinal vessels
Peripheral retinal ischemia –increased metabolic demands, the O2
regulated VEGFs and non-O2 regulated IGF-1 are produced in excess
resulting Neovascularization and fibrous proliferation of Retina

7. Role of VEGF and IGF-1 in the Pathogenesis of ROP

8. Clinical features of ROP
ICROP (2005)- is based on:
1.Location (Zone) 2. Stage 3. and Extent.
1. Location(ZONE):- Retina is divided into 3 Zones,
with optic nerve as the center.

9. 2. Staging of ROP (1-5)
• Stage- 1: (Demarcation line)

10. Stage-2:(Elevated ridge)

11. Stage-3: (Neovascularization)

12. Stage-4a:- Partial detachment not involving macula.
Stage-4b:- Partial detachment involving the macula.
Stage-4: (Partial RD)

13. 1. Open-Open funnel
2. Open-Narrow funnel
3. Narrow-Open funnel
4. Narrow-narrow funnel
Stage-5: Total RD

14. 3. Extent of ROP
• Divide the retinal surface into 12 segments (clock
hours)
• Stage of retinopathy can vary among segments.

15. Other features
1. Plus disease
2. Pre-plus disease
3. Aggressive posterior ROP (AP-ROP)
4. Threshold disease
5.Pretheshold disease : 2 types (Type-1 and Type-2)

16. 1. Plus disease
• Venous dilatation or arteriolar tortousity in at least 2
quadrant.
• Poor pupil dilatation
• Vitreous haze
• Vascular engorgement of the iris
• Hallmark of rapidly progressive ROP

17. 2. Pre-Plus disease
• Is labeled when venous dilation and arterial
tortuosity is more than normal but
insufficient to be defined as plus disease.

18. 3. Aggressive Posterior ROP(AP-ROP)
• Is a severe form of ROP that rapidly causes TRD.
• Direct AV shunting
• Neovascularization may be Flat, featureless

19. 4. Threshold disease
• If 5 or more contiguous or 8 cumulative clock
hours (30 degree) of stage 3 with plus disease
in either zone 1 or 2 are present.
• Chances of blindness (50%).

20. 5. Pre-threshold ROP
ETROP group has classified prethreshold disease into 2 types:
Type-1: (High risk prethreshold disease)- Treatment is
recommended within 72 hours.
Zone-1: Plus disease, any stage
Zone-2: Non-plus disease, stage3
Zone-3: Plus disease stage2 and stage3
Type-2: (Low risk prethreshold disease)-Requires observation
Zone-1: Nonplus disease, stage1 and2
Zone-2: Nonplus disease stage 3

21. Differential Diagnosis of ROP
1. Retinoblastoma
2. Cataract
3. PHPV
4. Familial Exudative vitreoretinopathy (FEVR)
5. Coat’s disease
6. Endophthalmitis
7. Chronic vitreous hge
8. Retinochoroidal coloboma

22. Management of ROP
1. Screening of risk babies
2. Diagnosis
3. Decision to treat or not
4. Medical Treatment
a. Cryotherapy(Mostly outdated)
b. Laser treatment (gold standard)
c. Anti-VEGF(adjuvant) before laser and Surgery
Correction of systemic factors
Rx of ROP related complication
5. Post treatment follow up
6. Low Vision Management/Rehabilitation

23. Screening
Whom to Screen?
1. Birth weight<1500gm
2. Gestational age <32wks
3. Between 1500-2000gm or gestational age >30wks if
they have been ill (RDS, Hypotension, Surgery)
4. Need for cardio respiratory support
5. Prolonged O2 therapy
6. Apnea of prematurity
7. Neonatal sepsis
8. If thought by the neonatologist to be high risk

24. How to screen?
Preparation:
-Prior informed and written consent from parents
-Temperature controlled room
-Ensure stability of infants
Dilatation of pupil:
Phenylephrine 2.5% and Tropicamide 0.5%
1 drop of Tropicamide every 10-15 minutes for 4times

25. Procedure
Performed by Experienced Ophthalmologist
• Indirect Ophthalmoscopy using 20D/28D lens
• Scleral depression is done to stabilize the eye, indent
it and contrast retina (For Plus Disease)
• Wire Speculum to keep the eyelids apart

26. Record Keeping
• Identification Data
• Gestation, birth
• Risk factors
• Date of first screening
• Findings of ROP
• Date of follow up

27. Wide field digital camera (Retcam) for
Screening
• Alternative to indirect Ophthalmoscope
• Provide retinal images at 130 degree
• High cost, limitation in diagnostic sensitivity,
specificity and accuracy.

28. Medical Treatment
1.Cryotherapy (Mostly outdated)
2. Laser Treatment(Gold standard)
3. Anti-VEGF (adjuvant) before laser and surgery
4. Surgery

29. 1. Cryotherapy

30. 2. Laser Therapy
• Laser Photocoagulation: Diod (red 810nm) or
frequency doubled Nd:YAG (532nm) with LIO
delivery should be carried out in all pts with high risk
prethreshold, threashold and AP-ROP.

31. 3. Anti-VEGF Treatment
Anti-VEGF:- Bevacizumab (Avastin)
-Ranibizumab (Lucentis)
Adjunctive therapy:
Injection to allow regression beyond Zone 1
- Laser for recurrent ROP
- Anti-VEGF as a bridge to laser peripherally
Perioperative Therapy before surgery:
- Reduce bleeding
-Promote regression of neovascularization
-Vitrectomy and Scleral Buckles

32. 4. Surgery

33. Scleral Buckle
• Done under GA
• Peritomy
• 2.5mm encircling band passed beneath 4 Recti
• One anchoring mattress suture applied in all
quadrant
• Removal after 3-6 months

34. Vitrectomy
• Necessary in advance cases
• Lensectomy avoided
• Peeling of membrane
• Relief of traction

35. Low Vision Management
1. High amount of myopic Refractive error can be
corrected with conventional spectacles or contact
lenses.
2. Magnification with microscopes, magnifiers
3. Electronic magnification systems and telesopic
devices
4. Various Tints and Filters may be useful in decreasing
photophobia
5. Increased, direct, nonglare illumination is helpful at
near
6. May also benefit from Field awareness systems and
mobility services if their peripheral field have been
affected.

36. References
1. Comprehensive Ophthalmology-by A.K Khurana
2. Clinical Ophthalmology- By Kanski’s Bowling
3. Essentials of Low Vision Practice-by Richard L.Brilliant
4. American Academy of Ophthalmology
5. Internet