Screening Examination of Premature Infants for Retinopathy of Prematurity

We are pleased to respond to Dr. Arnold’s questions.

Question 1.
Dr. Arnold is correct in questioning this. We have issued an erratum. The text should read: “immature retina extending into posterior zone II, near the boundary of zone I – zone II. The online version of this Policy Statement has already been corrected; the print erratum will be published in the Feb. or March issue of Pediatrics.

Question 2.
Dr. Arnold questions what the authors recommend for stage 3, zone II, no plus. The authors did not approach section 4 as requiring comment on every combination of disease severity and location. We did not specify stage 3, zone II, no plus.
This Policy Statement is a guideline; it is not our intent to eliminate clinical judgment by specifying every eventuality. The absence of plus disease in zone II means that this specific ROP does not yet require treatment. However, stage 3 ROP deserves careful monitoring. One to two week follow-up would be reasonable. Other considerations include the exact location, i.e., mid or anterior zone II vs. posterior or transitional zone II; current PMA e.g. 35 weeks may have more risk than 39 weeks; speed of progression e.g. last exam was stage 1 and hence rapidly progressive vs. stage 3 with no worsening. All these various situations require clinical judgment by the examining ophthalmologist.

Question 3.
Dr. Arnold again asks about a specific finding e.g. stage 1, zone II, plus. As stated above, we did not wish to preclude clinical judgment by being overly specific. In the light of current available data Stage 1, Zone II, plus disease does not require treatment but does require very careful monitoring so that any sign of progression can be treated promptly. Moreover, any plus deserves careful monitoring. Most of us would see that baby in one week, but many variables enter into the examining physician’s decision. This form of ROP is very rare.

Question 4.
Dr. Arnold asks about zone III. There is a paucity of data on treatable zone III disease. Disease of any stage, confined to zone III does not result in unfavorable anatomic outcomes as defined by the major US multicenter trials, though macular heterotopia or dragging which may have serious visual consequences has been noted rarely. However, disease can be confined to the temporal retina and hence a stage III, zone II confined to temporal retina can become zone III because the nasal retina continues to fully vascularize. This eventuality was recognized by Repka (reference No. 22) and is addressed in the guidelines in section 5. Once again, all these various situations require clinical judgment by the examining ophthalmologist.