1. Infants with birth weight of less than 1500 g or gestational age of 30weeks or less, (as defined by the attending neonatologist), and selected infants with birth weight between 1500 and 2000 g or gestational age of more than 30 weeks with an unstable clinical course, including those requiring cardiorespiratory support and who are believed by their attending pediatrician or neonatologist to be at high risk, should have retinal screening examinations performed after pupillary dilation using binocular indirect ophthalmoscopy to detect ROP. One examination is sufficient only if it unequivocally shows the retina to be fully vascularized in each eye. Effort should be made to minimize the discomfort and systemic effect of this examination by pretreatment of the eyes with a topical anesthetic agent, such as proparacaine; consideration may also be given to the use of pacifiers, oral sucrose, etc.

2. Retinal examinations in preterm infants should be performed by an ophthalmologist with sufficient knowledge and experience to enable accurate identification of the location and sequential retinal changes of ROP. The “International Classification of Retinopathy of Prematurity”⁹should be used to classify, diagram, and record these retinalfindings at the time of examination.

3. The initiation of acute-phase ROP screening should be based on the infant’s age. The onset of serious ROP correlates better with postmenstrual age (gestational age at birth plus chronologic age) than with postnatal age.¹⁰ That is, the youngest infants at birth take the longest time to develop serious ROP. This knowledge has been used previously in conducting a screening schedule.^11-12 Table 1 was developed from an evidence-based analysis of the Multicenter Trial of Cryotherapy for Retinopathy of Prematurity natural history data and confirmed by the Light Reduction in ROP Study conducted a decade later.¹³ It represents a suggestedschedule for timing of the initial eye examinations based on postmenstrual age and chronologic (postnatal) age to detect ROP before it becomes severe enough to result in retinal detachment while minimizing the number of potentially traumatic examinations.¹⁴ Table 1 provides a schedule for detecting ROPpotentially damaging to the retinawith 99% confidence.

4. Follow-up examinations should be recommended by the examining ophthalmologist on the basis of retinal findings classified according to the international classification.⁹ The following schedule is suggested (see Fig. 1):

1- week or less follow-up

• Stage 1 or 2 ROP – zone I
• Stage 3 ROP – zone II

1- to 2-week follow-up

• Immature vascularization – zone I – no ROP
• Stage 2 ROP – zone II
• Regressing ROP – zone I

2- week follow-up

• Stage 1 ROP – zone II
• Regressing ROP – zone II

2- to 3-week follow-up

• immature vascularization – zone II – no ROP
• stage 1 or 2 ROP – zone III
• regressing ROP – zone III

The presence of plus disease (defined as dilation and tortuosity of the posterior retinal blood vessels, see below) in zones I or II suggests that peripheral ablation, rather than observation, is appropriate.¹⁴

• zone I ROP – any stage with plus disease
• zone I ROP – stage 3 – no plus disease
• zone II – stage 2 or 3 with plus disease

Plus disease is defined as a degree of dilation and tortuosity of the posterior retinal blood vessels as defined by a standard photograph.^1,9 Special care must be used in determining the zone of disease. The number of clock hours of disease mayno longer be the determining factor in recommending ablative treatment. Treatment should generally be accomplished, whenpossible, within 72 hours of determination of treatable disease to minimize the risk of retinal detachment.

6. The conclusion of acute retinal screening examinations should be based on age and retinal ophthalmoscopic findings.¹⁴ Findings that suggest that examinations can be curtailed include the following:

• zone III retinal vascularization attained without previous zone I or II ROP (If there is examiner doubt about the zone or if the postmenstrual age is less than 35 weeks,confirmatory examinations may be warranted);
• full retinal vascularization.
• postmenstrual age of 45 weeks and no prethreshold disease (defined as stage 3 ROP in zone II, any ROP in zone I) or worse ROP is present; or
• regression of ROP.¹⁵ (Care must be taken to be sure there is no abnormal vascular tissue present capable of reactivation and progression.

7. Communication with the parents by members of the staff is very important. Parents should be aware of ROP examinations and should be informed if their child has ROP, with subsequent updates on ROP progression. The possible consequences of serious ROP should be discussed at the time that a significant risk of poor visual outcome develops. Documentation of such conversations with parents in the nurse or physician notes is highly recommended.

8. Responsibility for examination and follow-up of infants at risk of ROP must be carefully defined by each neonatal intensive care unit. Unit-specific criteria with respect to birth weight and gestational age for examination for ROP should be established for each NICU by consultation and agreement between neonatology and ophthalmology services. These criteria should be recorded and should automatically trigger ophthalmologic examinations. If hospital discharge or transfer to another NICU or hospital is contemplated before retinal maturation into zone III has taken place, or if the infant has been treated by ablation for ROP and is not yet fully healed,the availability of appropriate follow-up ophthalmologic examination must be ensured, and specific arrangement for that examination must be made before such discharge or transfer occurs. The transferring primary physician, after communication with the examining ophthalmologist, should have the responsibility of communicating what eye examinations are needed and their required timing to the infant’s new primary physician. The new primary physician should ascertain the current ocular examination status of the infant from the record and through communication with the transferring physician so that any necessary examinations by an ophthalmologist with ongoing experience and expertise in examination of preterm infants for ROP can be arranged promptly at the receiving facility or on an outpatient basis if discharge is contemplated before the need for continued examination has ceased, as outlined in recommendation 6. If responsibility for arranging follow-up ophthalmologic care after dischargeis delegated to the parents, they should be made tounderstand the potential for severe visual loss, including blindness; that there is a critical time window to be met if treatment is to be successful; and that timely follow-up examination is essential to successful treatment. This information should preferablybe communicated bothverbally and in writing. If such arrangements for communication andfollow-up after transfer or discharge cannot be made, the infant should not be transferred or discharged until appropriate follow-up examination can be arranged by the unit discharging the infant.

Pediatricians and other practitioners caring for infants who have had ROP, whether requiring treatment or not, should be aware that these infants may be at risk of other seemingly unrelated visual disorders, like strabismus, amblyopia, cataract, etc. Ophthalmologic follow-up for these potential problems after discharge from the NICU is indicated.

This statement replaces the previous statement on ROP from the AmericanAcademy of Pediatrics, American Association for Pediatric Ophthalmology and Strabismus, and AmericanAcademy of Ophthalmology¹⁶; is evolving; and may be modified as additional ROP risk factors, treatments, and long-term outcomes are known. 

1. Cryotherapy for Retinopathy of Prematurity Cooperative Group. Multicenter trial of cryotherapy for retinopathy of prematurity. Preliminary results.
2. Cryotherapy for Retinopathy of Prematurity Cooperative Group. Multicenter trial of cryotherapy for retinopathy of prematurity: ophthalmological outcomes at 10 years.
3. McNamara JA, Tasman W, Brown GC, Federman JL. Laser photocoagulation for stage 3+ retinopathy of prematurity.
4. 4.Hunter DG, Repka MX. Diode laser photocoagulation for threshold retinopathy of prematurity. A randomized study.
5. .Laser ROP Study Group. Laser therapy for retinopathy of prematurity. 1994;112:154-156
6. Iverson DA, Trese MT, Orgel IK, Williams GA. Laser photocoagulation for threshold retinopathy of prematurity. Arch Ophthalmol. 1991;109-1342-1343
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13. Reynolds JD, Hardy RJ, Kennedy KA, Spencer R, van Heuven WA, Fielder AR. Light Reduction in Retinopathy of Prematurity (LIGHT-ROP) cooperative group. Lack of efficacy of light reduction in preventing retinopathy of prematurity. N Engl J Med 1998;338:1572-1576
14. Reynolds JD, Dobson V, Quinn GE, et al. CRYO-ROP and LIGHT-ROP Cooperative Groups. Evidence-based screening criteria for retinopathy of prematurity: natural history data from the CRYO-ROP and LIGHT-ROP studies. Arch Ophthalmol 2002;120:1470-1476
15. Repka MX, Palmer EA, Tung B. Cryotherapy for Retinopathy of Prematurity Cooperative Group. Involution of retinopathy of prematurity. Arch Ophthalmol
16. American Academy of Pediatrics, Section on Ophthalmology, American Academy of Ophthalmology, and American Association for Pediatric Ophthalmology and Strabismus. Screening examination of premature infants for retinopathy of prematurity. Pediatrics 2001;108:809-811