The stage of ROP refers to the character of the leading edge of growing retinal blood vessels (at the vascular-avascular border). Monitoring
In order to allow timely intervention, a system of monitoring is undertaken for infants at risk of developing ROP. These monitoring protocols differ geographically because the definition of high-risk is not uniform or perfectly defined. In the USA the consensus statement of experts is informed by data derived by clinical trials and published in Pediatrics 2006. They included infants with birthweights under 1500 grams or under 30 weeks gestation in most cases. The first examination should take place within the first 4 weeks of birth, and regular, weekly examination is required until it is clear that the eyes are not going to develop disease needing treatment, or one or both eyes develop disease requiring treatment. Treatment should be administered within a 48 hours, as the condition can progress rapidly. Management
Treatment
Peripheral retinal ablation is the mainstay of ROP treatment. The destruction of the avascular retina is performed with a solid state laser photocoagulation device, as these are easily portable to the operating room or neonatal ICU. Cryotherapy, an earlier technique in which regional retinal destruction was done using a probe to freeze the desired areas, has also been evaluated in multi-center clinical trials as an effective modality for prevention and treatment of ROP. However, when laser treatment is available, cryotherapy is no longer preferred for routine avascular retinal ablation in premature babies, due to the side effects of inflammation and lid swelling.
Restricting supplemental oxygen use reduces the rate of ROP, but may raise the risk of other hypoxia-related systemic complications, including death.Patients with ROP, particularly those who have developed severe disease needing treatment are at greater risk for strabismus, glaucoma, cataracts and shortsightedness (myopia) later in life and should be examined yearly to help prevent or detect and treat these conditions. Diagnosis
The stages of ROP disease have been defined by the International Classification of Retinopathy of Prematurity (ICROP). In older patients, the appearance of the disease is less well described but includes the residua of the ICROP stages as well as secondary retinal responses. International classification
The system used for describing the findings of active ROP is entitled The International Classification of Retinopathy of Prematurity (ICROP). ICROP uses a number of parameters to describe the disease. They are location (zone) of the disease, the circumferential extent of the disease based on the clock hours, the severity (stage) of the disease and the presence or absence of "Plus Disease". Each aspect of the classification has a technical definition. This classification was used for the major clinical trials. It was revised in 2005. The zones are centered on the optic nerve. Zone I is the posterior zone of the retina, defined as the circle with a radius extending from the optic nerve to double the distance to the macula.