Retinopathy of prematurity: An update on screening and management

Question 1

What is ROP?

Answer 1

a proliferative disorder of the developing retinal blood vessels in preterm infants, may lead to poor visual acuity or blindness

Question 2

What percentage of neonates born <31wks GA develop some stage of ROP?

Answer 2

40-50%

Question 3

What percentage of neonates born <31wks GA develop severe ROP?

Answer 3

7-8%

Question 4

What percentage of neonates born <31wks GA require ROP treatment?

Answer 4

5-6%

Question 5

What are the stages of ROP?

Answer 5

Stage 1 - demarcation line separating avascular from vascularized retina

Stage 2 - Ridge arising in region of demarcation line

Stage 3 - Extraretinal fibrovascular proliferation/neovascularization extending into the vitreous

Stage 4 - Partial retinal detachment

Stage 5 - Total retinal detachment

Plus disease - Increased vascular dilatation and tortuosity of posterior retinal vessels in at least two quadrants of the retina

Pre-plus disease - More vascular dilatation and tortuosity than normal but insufficient to make the diagnosis of plus disease

Type 1 ROP:

a) Zone I – any stage ROP with plus disease as well as stage 3 ROP without plus disease
b) Zone II – stage 2 or 3 ROP with plus disease

Type 2 ROP

a) Zone I – stage 1 or 2 ROP without plus disease
b) Zone II – stage 3 ROP without plus disease

Question 6

What are the current indications for treatment of ROP (Type 1 ROP)?

Answer 6

1. Zone I – any stage ROP with plus disease
2. Zone I – stage 3 ROP without plus disease
3. Zone II – stage 2 or 3 ROP with plus disease

Question 7

What is the recommendations regarding ROP screening in Canada?

Answer 7

1. All infants <31 weeks GA
2. Infants = 1250g
3. Infants believed to be at high risk for ROP

Question 8

When should the first ROP screening examination occur?

Answer 8

At 31 weeks GA for infants 22-27 weeks GA

At 4 weeks chronological age for infants born at >28 weeks GA

Question 9

What type of screening can be used in the community?

Answer 9

Digital retinal photography

Question 10

What methods should be used for analgesia in pain control?

Answer 10

1. Pacifiers
2. Topical anesthetics
3. Swaddling
4. Sucrose

Question 11

What are indications for follow-up in >1 week?

Answer 11

1. Immature vascularization, zone 1 - no ROP
2. Immature retina extends into posterior zone II, near boundary of zone I
3. Stage 1 or 2 ROP, no plus disease, zone I
4. Stage 3 ROP, no plus disease, zone II
5. Presence or suspected presence of aggressive posterior ROP
6. Inability to determine zone due to hazy view

Question 12

What are the indications for follow-up in 1-2 weeks?

Answer 12

1. Immature vascularization, posterior zone II

2. Stage 2 ROP, no plus disease, zone II

Question 13

What are the indications for follow-up in 2 weeks?

Answer 13

1. Stage 1 ROP, no plus disease, zone II
2. Immature vascularization, zone II – no ROP
3. Unequivocally regressing ROP, zone II

Question 14

What are indications for follow-up in 2-3 weeks?

Answer 14

1. Stage 1 or 2 ROP, no plus disease, zone III

2. Regressing ROP, zone III

Question 15

What are the indications to stop screening?

Answer 15

1. Vascularization in zone III without previous zone I or II ROP
2. Full retinal vascularization in close proximity to the ora serrata for 360°
3. Postmenstrual age of 50 weeks and no prethreshold or worse ROP
4. Regression of ROP (no abnormal vascular tissue capable of reactivation and progression present in zone II or III)

Question 16

What are the options for treatment?

Answer 16

1. Retinal ablation with laser photocoagulation within 72h of detection
2. Antivascular endothelial growth factor (anti-VEGF) therapy recent and controversial