Update on retinopathy of prematurity

Dopamine use is an indicator for the development of threshold retinopathy of prematurity

AIM

To assess whether treatment of premature infants with dopamine is a risk factor for development of retinopathy of prematurity (ROP).

METHODS

A retrospective case series analysis of two groups was utilised with a minimum follow up of 6 months. Clinical profiles and patient risk factors were identified along with an evaluation of ROP progression and an analysis of clinical outcome. All infants were seen in a single community neonatal intensive care unit (NICU). 41 consecutive high risk infants were identified during a 36 month period whose birth weight was less than 1000 grams and who remained in the NICU without transfer until at least 28 days of age. Dilated indirect ophthalmoscopy fundus examinations were performed on all infants to identify the degree of and progression to threshold ROP.

RESULTS

18 of 41 infants were treated with dopamine for hypotension. The group of infants requiring dopamine differed statistically from the non-dopamine treated group by having a slightly higher birth weight, a greater incidence of hypotension and colloid treatment, and in manifesting more advanced respiratory disease. Within the dopamine treated group, 12 of 18 infants (67%) reached prethreshold ROP and seven infants (39%) reached threshold ROP requiring laser treatment. In contrast, only three of the infants (13%) who did not require dopamine for hypotension progressed to prethreshold (p = 0.001) and only one of these infants (4%) progressed to threshold ROP (p = 0.02). Logistic regression analysis among other variables demonstrated that dopamine use and gestational age are important factors in this low birthweight population for predicting the development of threshold ROP (dopamine use: adjusted odds ratio = 119.88, p = 0.0061; gestational age: adjusted odds ratio = 0.061, p = 0.0043).

CONCLUSIONS

Dopamine use in low birthweight infants may therefore be a risk factor for the development of threshold ROP. More vigilant screening of high risk infants requiring dopamine therapy for systemic hypotension may be warranted.

Retinopathy of prematurity in the 1990s

Infants diagnosed with retinopathy of prematurity (ROP) are at risk for developing visual impairments. The International Classification of ROP (ICROP) developed the most useful tool available for communicating the location and extent of the condition, with three zones to describe the location and five stages to describe the extent. Despite current knowledge and treatment, however, 500 infants are blinded each year by ROP. Infants at highest risk are the smallest and most immature. The nurse must understand why and how ROP occurs and the forms of management used to treat ROP. This article reports on the incidence, pathophysiology, risk factors, screening, treatment, and long-term complications of ROP in the 1990s.

Are we screening too many babies for retinopathy of prematurity?

A retrospective, hospital-records-based study of neonates screened for retinopathy of prematurity (ROP) was undertaken to determine whether the inclusion criteria for screening could have been safely altered to reduce the numbers of babies screened whilst not missing any stage III disease. Babies from six neonatal intensive care units in Birmingham were screened by a single examiner. Between November 1989 and November 1995, 1611 babies were examined and 1429 of these fell within the inclusion criteria of current guidelines for ROP screening produced by the Royal College of Ophthalmologists and the British Association of Perinatal Medicine--any baby < or = 1500 g birthweight or < or = 31 weeks gestational age. Thirty-nine (39) babies developed stage III ROP of which 31 (2.2%) were from Birmingham. In addition 8 babies with stage III ROP were referred from elsewhere. All 39 babies with stage III ROP had a birthweight < or = 1250 g or a gestational age of < or = 29 weeks, but 2 fell outside one criterion, indicating the need for both to be used. Had these inclusion criteria been utilised during this period, then 30% fewer babies would have been examined (432 of 1429). The importance of using both birthweight and gestational age as inclusion criteria is discussed, and the dangers of altering the indications for national screening on the basis of one study population is emphasised.

Current concepts in retinopathy of prematurity

Significant advances regarding understanding the etiology and treatment of retinopathy of prematurity have occurred in the 50 years since its discovery. Nevertheless, there is still a great deal to be learned. In spite of major technological advances in neonatal care, retinopathy of prematurity is a multi-factorial disease and probably cannot be completely prevented. Early intervention in the diagnosis and management of these infants has greatly improved their visual prognosis. Further studies may help pediatricians and neonatologists to understand and control associated risk factors. Ophthalmologists must continue to examine these patients early and follow them closely to control the associated treatable aspects of the disease, such as strabismus and amblyopia.

Screening for retinopathy of prematurity

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Natural history of retinopathy of prematurity: a prospective study

The natural history of retinopathy of prematurity (ROP) has been studied prospectively in 572 infants < or = 1,700 g birthweight using a protocol designed specifically to investigate the subtle features of this condition. Acute ROP developed in 50.9%. All ROP stages 1 and 2 underwent complete resolution and of the 27 (4.7%) infants with stage 3/4 disease, cicatricial sequelae developed in six. Incidence and severity increased with decreasing birthweight and gestational age. Onset was not confined to the temporal retina but exhibited a predilection to start first in the nasal retina of the most immature neonate. The vertical retinal regions were relatively spared. Retinal arteriolar tortuosity developed around three months postnatally and was related to ROP severity but not its presence. The age at onset and rate of progression of retinopathy were largely determined by the stage of development but were also modified by systemic and local factors. The relevance of these findings to ROP screening is discussed.