Karolinska Institutet
Browse

Ophthalmological aspects of prematurity

thesis
posted on 2024-09-03, 03:29 authored by Gerd Holmström

In a prospective, population-based study of a weIl defined geographical area in Sweden, an ROP incidence of 40.4% was found among 260 prematurely born infants with a birth weight of 1500 grams or less. Cryotherapy was performed in 10.8% of the infants. Gestational age at birth and birth weight were significantly associated with ROP.

A 3.5-year ophthalmological follow-up of the 260 prematurely born infants was performed. In the refraction there was a reduction in the mean spherical equivalents with increasing degrees of ROP. Myopia (examination at 2 1/2 years) was commonest in eyes with ROP (18% of right eyes, 15% of left eyes), particularly in those treated with cryo (40%/27%). Astigmatism was associated with ROP, but not with cryotherapy per se. Astigmatism was also associated with low birth weight. Marked anisometropia was related to cryotreated ROP. A visual handicap (visual acuity <0.3) was found in 2.5% of the children and severe visual impairment (visual acuity <0.1) was present in two children (0.8%), of whom one was blind. Neurological complications and the degree of ROP, including cryotreated ROP, were significant risk factors for poor vision. Strabismus, seen in 13.5% of the total study population, was significantly associated with neurological lesions and their sequelae, anisometropia and cryotreated ROP. Prematurely born infants without ROP ran an increased risk of myopia, anisometropia and strabismus as compared to a normal population, which emphasizes the need for ophthalmological follow-up of pre term infants even with out ROP.

In a selected group of children with preterm cerebral lesions, visual impairment was commoner in children with ischaemic lesions (leucomalacia and infarcts) than in children with haemophagic lesions. Pathological"crowding" in visual acuity assessment was also most commonly seen in ischaemic lesions, which implied an overestimate of vision by tests with solid objects and single optotypes in relation to linear optotype acuity. Difficulties in interpreting complex pictures were found in the whole study group. In a retrospective study of the mothers of infants from the population-based study, essential hypertension before pregnancy was the only maternal risk factor associated with ROP in a logistic, multiple regression analysis. Among risk factors for preterm birth in our population, socioeconomic factors (marital status and education), as well as smoking, played a less prominent role than in previous studies. In a retrospective study of neonatal risk factors in the same population, gestational age at birth, bronchopulmonary dysplasia, and low birth weight were significantly associated with ROP. In both studies, prematurity per se remained the strongest risk factor for ROP.

Screening for ROP in our area is recommended for infants with a gestational age at birth of 32 weeks or less, and long-term ophthalmological follow-up is suggested for all of them, with particular emphasis on those infants that run the highest risk of complications - i.e., those who have had cryotherapy and/or have neurological complications.

List of scientific papers

I. Holmström G, el Azazi M, Jacobson L, Lennerstrand G (1993). "A population based, prospective study of the development of ROP in prematurely born children in the Stockholm area of Sweden." Br J Ophthalmol 77(7): 417-23
https://pubmed.ncbi.nlm.nih.gov/8343469

II. Holmström G, el Azazi M, Kugelberg U (1999). "Ophthalmological follow up of preterm infants: a population based, prospective study of visual acuity and strabismus" Br J Ophthalmol 83(2): 143-50
https://pubmed.ncbi.nlm.nih.gov/10396188

III. Pike MG, Holmstrom G, de Vries LS, Pennock JM, Drew KJ, Sonksen PM, Dubowitz LM (1994). "Patterns of visual impairment associated with lesions of the preterm infant brain." Dev Med Child Neurol 36(10): 849-62
https://pubmed.ncbi.nlm.nih.gov/7926317

IV. Holmström G, Thomassen P, Broberger U (1996). "Maternal risk factors for retinopathy of prematurity--a population-based study." Acta Obstet Gynecol Scand 75(7): 628-35
https://pubmed.ncbi.nlm.nih.gov/8822655

V. Holmström G, Broberger U, Thomassen P (1998). "Neonatal risk factors for retinopathy of prematurity--a population-based study." Acta Ophthalmol Scand 76(2): 204-7
https://pubmed.ncbi.nlm.nih.gov/9591954

History

Defence date

1996-10-04

Department

  • Department of Clinical Neuroscience

Publisher/Institution

Karolinska Institutet

Publication year

1996

Thesis type

  • Doctoral thesis

ISBN-10

91-628-2158-X

Number of supporting papers

5

Language

  • eng

Original publication date

1996-09-13

Author name in thesis

Holmström, Gerd

Original department name

Department of Clinical Neuroscience

Place of publication

Stockholm

Usage metrics

    Theses

    Categories

    No categories selected

    Keywords

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC