Table 3.

Suggested follow-up schedule for retinopathy of prematurity (ROP) screening

Follow-up	Indications	Modifications
1 week or less	Immature vascularization, zone I – no ROP Immature retina extends into posterior zone II, near boundary of zone I Stage 1 or 2 ROP, no plus disease, zone I Stage 3 ROP, no plus disease, zone II Presence or suspected presence of aggressive posterior ROP Inability to determine zone due to hazy view	Added immature vascularization, immature retina and aggressive posterior ROP
1 to 2 weeks	Immature vascularization, posterior zone II Stage 2 ROP, no plus disease, zone II
2 weeks	Stage 1 ROP, no plus disease, zone II Immature vascularization, zone II – no ROP Unequivocally regressing ROP, zone II	Added immature vascularization
2 to 3 weeks	Stage 1 or 2 ROP, no plus disease, zone III Regressing ROP, zone III
Stop screening	Vascularization in zone III without previous zone I or II ROP Full retinal vascularization in close proximity to the ora serrata for 360° Postmenstrual age of 50 weeks and no prethreshold or worse ROP Regression of ROP (no abnormal vascular tissue capable of reactivation and progression present in zone II or III)	Changed postmenstrual age from 45 weeks to 50 weeks

Adapted from reference 3