How to Diagnose Retinopathy of Prematurity

Retinopathy of prematurity is a disease that affects the vasculature of the eyes of premature babies. It may range in severity from mild with no visual defects or to aggressive, forming new blood vessels and causing blindness. The incidence of retinopathy of prematurity is increasing as more premature babies are surviving. The following steps will show how to diagnose retinopathy of prematurity.

Instructions

Difficulty: Moderate

1. Consider the age of the patient. Retinopathy of prematurity is exclusively a disease of premature infants and all babies born at less than 32 weeks of gestation or weighing less than about 3 and a half pounds are at risk of developing the condition. One fifth of all of these babies will develop some degree of retinopathy of prematurity by the time they are 3.
2. Conduct a dilated fundus examination with scleral depression. Use a Sauer speculum to keep the eyes gently open and a Flynn scleral depressor to depress and rotate small eyes. Use a 28 diopter lens to identify the areas of the eye retinopathy of prematurity affects.
3. Perform the first part of the examination externally to detect the presence of any iris rubeosis. Examine the posterior pole next for any straightening of the vascular arcades.
4. Rotate the eye to determine the extent of the nasal blood vessels. The presence of the ridge of the nasal blood vessels in the same view with the optic nerve indicates Zone 1 retinopathy of prematurity. If the nasal blood vessels have not reached the nasal ora serrata, it is Zone 2 and if they have reached this point it is zone 3.
5. Classify the severity of the retinopathy of prematurity. This is essentially based upon the degree of demarcation between vascularized and nonvascularized retina with greater demarcation indicating a more severe form of retinopathy of prematurity.