Date of Award

January 2017

Document Type


Degree Name

Medical Doctor (MD)



First Advisor

Ron A. Adelman


Modern technological developments in neonatal care have heralded changing rates of Retinopathy of Prematurity (ROP) and attitudes toward surgical treatments. In this study, our purpose was twofold. We examined: 1) ROP incidence in the United States and trends in patient and treating hospital characteristics over the last 16 years; 2) usage of the 5 most prevalent surgical treatments over time. Using a national database, we queried 53,874 infants with an ICD-9 diagnosis of ROP between 1/1/1998-12/31/2013. Birth weight, gestational age, hospital charges, length of stay, race, primary payor, and gender were assessed. Incidence was determined among infants with prolonged hospital stays of ≥28 days or all infants born prematurely (<37weeks). Furthermore, the rate of usage of laser, vitrectomy, scleral buckle, diathermy, cryotherapy and their relationship with birth weight, gestational age, ROP stage and age at the time of procedure were assessed. Incidence in infants with prolonged hospital stays increased significantly from 15.9% to 20.5% (P=0.0088) but there was no significant change among all infants born prematurely (P=0.1177). over 2008-2013, rates of severe (vision-threatening) disease parallel those in other developed countries: 14% percent of ROP patients had severe disease (stages ≥3). In 2013, 5% of patients received any procedure, compared to 22% in 1998. Surgical rates varied inversely with gestational age and birth weight. Laser replaced vitrectomy as the most common procedure. Laser was performed earliest and vitrectomy and scleral buckle the latest (mean 84 vs. 135, 136 days of age, respectively). About one-fifth of patients with scleral buckle or cryotherapy also had laser in the same stay. Vitrectomy was performed along with one-quarter of scleral buckle patients and one-third of cryotherapy patients, and half of diathermy patients in the same stay. This study is the largest known survey of ROP infants. Total charges for stays in rural hospitals were almost quadruple those in urban ones ($205,202 vs. $54,601) and length of stay almost double in rural hospitals (50 vs. 26 days, respectively). Rates of severe ROP in the US (14%) parallel those in other developed countries. Declining overall surgical rates may reflect improved modern medical management of ROP and prematurity in general. Declining vitrectomy rates over this period likely reflect increasing success and acceptance of laser treatments, which have better visual outcomes. As costs and length of stay increase, large, urban hospitals treat more ROP than ever, and these centers are highly cost efficient compared to rural counterparts.


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