Myopia in premature babies with and without retinopathy of prematurity.

One hundred and fifty-five premature infants weighing 600-2000 g were followed up during 1974-80 for the presence of retinopathy of prematurity (ROP) and for the existence of myopia. 50% of the premature infants who had ROP were myopic, while only 16% myopic premature infants were found among those who did not have ROP. There was a positive correlation between the degree of myopia and the severity of cicatricial ROP. No difference existed in the frequency and degree of myopia between premature infants in which ROP cicatrised spontaneously and in those where it cicatrised after cryopexy.     

Visual acuity in infants after vitrectomy for severe retinopathy of prematurity

During the course of the Multicenter Trial of Cryotherapy for Retinopathy of Prematurity (CRYO-ROP), 98 infants (129 eyes) from the randomized segment of the trial developed total retinal detachment from retinopathy of prematurity (ROP) before the 1-year examination. The authors report as a case series the results of acuity card assessment of monocular grating acuity at 1 year in 53 infants (71 eyes) postvitrectomy and in 45 infants (58 eyes) who had retinal detachments but who did not undergo retinal reattachment surgery. The decision to undertake and the surgical technique used for a retinal reattachment procedure was not part of the randomized CRYO-ROP trial. Two eyes of one infant had pattern vision at the lowest measurable threshold after vitrectomy. None of the remaining eyes that had undergone vitrectomy and none of the eyes that did not undergo vitrectomy showed evidence of pattern vision. The relatively poor visual outcomes in this case series suggest that efforts are well-spent in attempting to prevent retinal detachment in ROP.     

Systemic candidiasis in babies with retinopathy of prematurity

Fifteen premature babies developed systemic candidiasis during the administration of intravenous hyperalimentation in the Beilinson Neonatal Intensive Care Unit. Candida albicans was found in the blood cultures of all the babies and in the urine cultures of 66.7% of them. Repeated funduscopic examinations revealed no evidence of septic embolization in the retinal or choroidal circulation. It should be noted that acute retinopathy of prematurity (ROP) grade 2 or 3 was found in all the babies.     

Spatial aberrations and acuity in strabismus and amblyopia

Spatial uncertainty and distortion were quantified from judgement of the horizontal position of a flashed 0.5 deg vertical line with respect to a flanking reference target in strabismics with and without reduced acuity. Spatial uncertainty was outside the range of 30 normal eyes in all of 23 strabismic amblyopic eyes (visual acuity = 20/40 or worse) and in 20 of 22 squinting eyes with 20/30 or better acuity. Abnormal spatial distortion was found in 16 amblyopic and 10 squinting eyes. In the deviated eyes of the strabismics, the extent of spatial uncertainty and distortion correlated with visual acuity. Spatial aberrations were not accounted for by strabismics' unsteady or eccentric fixation, nor were they mimicked in normal eyes when visual acuity was artifically reduced. The authors suggest that spatial uncertainty and distortion represent the primary abnormalities in strabismics and produce deficits of visual acuity according to their severity.     

Clinical features of premature twin babies with intersibling asymmetry of retinopathy of prematurity severity

ObjectiveTo report the clinical features of premature twin babies showing intersibling asymmetry in their severity of retinopathy of prematurity (ROP) and analyze risk factors associated with development of severe ROP between twin siblings with discordant ROP severity.MethodsA retrospective study of records of 105 premature twin pairs was conducted. The criteria for discordant ROP with an intersibling difference in ROP severity were as follows: (i) two or more stages of difference in ROP between siblings, (ii) one sibling having treatment-requiring ROP and the other having no ROP or ROP that regressed spontaneously, or (iii) one sibling having aggressive posterior ROP and the other having staged or no ROP. Twin siblings were classified into two groups according to the severity of ROP (no or less ROP and more severe ROP). We examined ocular features in twins having intersibling asymmetry of ROP and analyzed perinatal risk factors for ROP.ResultsOf 105 twin pairs, 32 pairs (30.5%) showed intersibling asymmetry of ROP severity, and 15 pairs (14.3%) showed ROP asymmetry in terms of need for ROP treatment. The development of more severe ROP was associated with longer duration of oxygen supplementation and greater frequency of total blood and packed red blood cell transfusion (p = 0.020, p = 0.045, and p = 0.036, respectively). Longer duration of oxygen supplementation remained a statistically independent risk factor of severe ROP using multivariate logistic regression analysis.ConclusionsOphthalmologists caring for premature infants should be aware of the variable courses and progressions of ROP between twin babies. Longer duration of oxygen supplementation and greater frequency of blood transfusions were associated with higher ROP severity in twins.     

Follow-up study on premature infants with and without retinopathy of prematurity.

The ocular complications in population of 131 premature infants, with and without retinopathy of prematurity (ROP) are reported. An increased incidence of strabismus (20% with ROP and 25% without ROP) and myopia (27.5% with ROP and 8.8% without ROP) was shown. Significant visual loss occurred in 10.7% overall, increasing to 35% with stage 3 disease and 100% with stage 4. With the increased survival rate of premature infants, the relevance to future management of this expanding group of young people is considered.     

Unilateral amblyopia without strabismus and with anisometropia

PURPOSE OF THE STUDY: To evaluate a group of patients with unilateral isometropic amblyopia according to presence of possible amblyogenic factors. MATERIAL AND METHODS: 37 patients (18 girls and 19 boys) with unilateral amblyopia without strabismus and with anisometropia of less than 1 D in any of the meridians were analysed according to such possible risk factors of amblyopia as age of examination, age of mother on delivery, sex, family history, puerperal complications, birth weight, refraction error, left or right eye. Depth of amblyopia, state of binocular vision and results of optical and pleoptical treatment were also evaluated. RESULTS AND DISCUSSION: No significant risks were found regarding the age of patient, sex, left or right eye, birth weight, age of mother on delivery, puerperal complications and family history. Refraction error was not high. Depth of amblyopia did not correlate with amount of refraction error. Central fixation was present only in 50% and stereopsis only in 42% of patients. 10 patients revealed no significant defect of fixation or binocular vision. All patients responded significantly poorly to treatment. CONCLUSIONS: Presence of amblyopia in patients with isometropia cannot be explained by genetic or puerperal risk factors. It might have developed in the period sensitive for amblyopia as a result of anisometropia that was later diminished by the process of emmetropisation or microstrabismus which was spontaneously cured. Some cases can be described as idiopathic because no defect can be detected. Early in life screening is necessary to successfully diagnose and treat amblyopia in childhood.     

Refractive errors and ocular motility disorders in preterm babies with and without retinopathy of prematurity.

Ocular motility, refraction and visual acuity (VA) were evaluated at the age of 4 years in 136 preterm infants with gestational ages (GAs) at birth of less than 32 weeks. Group 1 (non-retinopathy of prematurity, ROP) included 87 children that had never developed ROP. Group 2 contained 19 children whose ROP had regressed spontaneously. Group 3 (cryo-ROP) was composed of 30 patients who had undergone cryotherapy for severe ROP. Strabismus was found in 13.9% of the total population. chi(2) analysis revealed that strabismus was significantly (p < 0.01) associated with prematurity (i.e. GA <29 weeks), ROP and cryotherapy. Myopia of more than 3 dpt was significantly (p < 0.001) more common in the cryo-ROP infants than in the regressed-ROP and non-ROP groups. The distribution of hypermetropia was similar in all three groups. VA was measured with the E chart. Of the 272 eyes examined, 251 (92.3%) displayed VA of more than 20/25. The majority of these eyes were from the non-ROP group (65.4%), 15.3% had regressed ROP and 21.1% belonged to the cryo-ROP group. Fifteen eyes (8 non-ROP, 3 regressed ROP and 4 cryo-ROP) presented VAs between 20/25 and 20/60. VA of less then 20/60 was found in 6 eyes (2 non-ROP, 1 regressed ROP, 3 cryo-ROP). Cryotherapy did not appear to preclude the development of good VA.     

Ocular growth and refractive error development in premature infants without retinopathy of prematurity

PURPOSE: This investigation studied the factors involved in the development of refractive error (RE) in premature infants unaffected by retinopathy of prematurity (ROP). METHODS: Premature infants enrolled in the national ROP screening program were recruited and examined at 32, 36, 40, 44, and 52 weeks' postmenstrual age. At each examination, axial length (AXL), anterior chamber depth (ACD), and lens thickness (LT) were measured on the A-scan biometer. Corneal curvature (CC) was recorded with a video-ophthalmophakometer, and refractive state was determined with routine cycloplegic refraction. Multilevel modeling techniques were used to determine the relationships between all the variables throughout the study period, as well as individual growth rates. RESULTS: Sixty-eight premature infants were included. AXL and ACD showed linear patterns of growth, whereas LT changed little over the study period. CC showed a quadratic growth pattern, and unlike the previous variables, correlated well with refractive state. Premature infants were myopes at the start of the study, with refraction becoming emmetropic as they neared full term and then hypermetropic toward the end of the study. CONCLUSIONS: Most of the components of refractive status showed linear patterns of growth during this early phase of ocular development. CC displayed a more complex pattern of growth, which correlated well with refractive state. Compared with full-term infants examined around term, this group has shorter AXLs, shallower anterior chambers, and more highly curved corneas. In addition, less of the expected hypermetropia developed in the premature group, which seems mainly due to the differences in ACD and corneal curvature.     

Visual acuity in premature infants

PURPOSE: To measure grating visual acuity in premature infants and compare it with that in full-term infants. METHODS: The visual acuity of 73 premature and 73 full-term infants was tested at 6 months of age by the Teller Acuity Card procedure. All premature infants had undergone indirect funduscopy for the detection of retinopathy of prematurity (ROP). Seven infants had developed ROP. The mean gestational age of the premature infants was 33 +/- 1.4 weeks as compared with 39.9 +/- 0.9 weeks in the full-term infants. The mean birth weights of the 2 groups were 1,906 +/- 412 and 3,244 +/- 420 g, respectively. RESULTS: Impaired binocular visual acuity was found in 53.4% of the premature infants, but in only 11% of the full-term infants (p < 0.0001). Impaired monocular visual acuity was found in 13.7% of the premature infants as compared with 2.7% of the full-term infants. Within the premature infant group, monocular visual acuity was impaired in 42.9% of those with ROP and in 10.6% of those without ROP (p = 0.0497). Pathological refraction was found in 33.3% of the prematures without ROP and in 14.3% of the prematures with ROP. This difference was not statistically significant. Visual acuity of preterm infants was not different from full-term infants when examined at 6 months of postconceptual age. CONCLUSIONS: Both monocular and binocular visual acuities as measured by the Teller Acuity Cards are worse in premature infants than in full-term infants at the same chronological age. Poor visual acuity in premature infants can be attributed mainly to immaturity of the visual system.     

Visual acuity and color vision deficiency in amblyopia

PURPOSE: To investigate color vision and its relation with the type of amblyopia and visual acuity of amblyopic eyes. METHODS: In this prospective study, 67 amblyopic eyes of 64 patients, aged from 4 to 13 years (mean 6.8 +/- 2.1) and 26 eyes of 13 control subjects aged from 5 to 13 years (mean 7.3 +/- 1.6) were examined with the Farnsworth-Munsell 100 Hue Test (FM-100). Amblyopic eyes were grouped as strabismic (21 eyes) and anisometropic (46 eyes). Each group was subdivided according to their visual acuity, as less than 5/10 and 6/10 or better. The total errors, blue-yellow (B-Y) and red-green (R-G) partial error scores were obtained for each group. One-way ANOVA was used to assess differences between groups. RESULTS: The error scores of all axes were lower in the control group than the amblyopic groups (p<0.001), but the differences within amblyopic groups were not significant (p>0.05). CONCLUSIONS: Deficient color vision in the amblyopic eyes was not related to the visual acuity and type of amblyopia.     

Correlation of central corneal thickness and associated factors in premature infants with and without retinopathy of prematurity

ObjectiveCentral corneal thickness (CCT) in premature infants is described in racially homogenous populations, and factors affecting CCT in infants are relatively unknown. This study describes CCT in premature infants and its association of steroid and oxygen requirements, gestational age (GA), birth weight (BW), race, and their relationship with CCT and corneal haze.MethodsCCT measurements of 87 infants/174 eyes screened for retinopathy of prematurity were taken between 30 and 44 weeks of GA. CCT was analyzed using a mixed model for its relationship with BW, GA, race, corneal clarity, steroid, and oxygen use.ResultsAverage CCT decreased at a rate of 12.3 μm/week. Caucasians had the thickest corneas and Hispanics the thinnest (p < 0.01) at baseline, but the rate of CCT decline varied based on racial/ethnic group (p = 0.079). Infants with BW <1000 g had a higher CCT at baseline, but CCT decreased at a faster rate than infants with higher BW (?13. 4 μm/week vs ?9.9 μm/week, p = 0.020). Infants born <27 weeks of GA had higher CCT at baseline, but CCT decreased at faster rate compared with patients born later (?13.3 μm/week vs ?10.1 μm/week, p = 0.029). Steroid and oxygen use were not statistically significantly associated with CCT or corneal haze (p > 0.05)ConclusionsCCT varies by racial group in premature infants. Lower BW and GA are associated with increased CCT at baseline but thin at a faster rate. Average, CCT decreases at a rate of 12.3 μm/week between 30 and 44 weeks GA and averages to 550 μm by 44 weeks GA.     

Visual outcome in infants with cicatricial retinopathy of prematurity

Monocular grating acuities of preterm infants with retinopathy of prematurity (ROP) were measured using a forced-choice preferential-looking (FPL) procedure. Eyes were independently graded by a retinal specialist and/or pediatric ophthalmologist and assigned to anatomic outcome categories on the basis of cicatricial residua of ROP. Eyes assigned to the normal/regressed and peripheral retinal changes categories (n = 120) had normal posterior poles. The authors found that grating acuities in this group were slightly lower than those of age-matched healthy full-term infants, even when infants with amblyogenic or neurologic conditions were eliminated from the analysis. Grating acuity of eyes assigned to the macular ectopia, macular fold, partial detachment, or total detachment outcome categories (n = 60) had abnormal posterior poles, and grating acuity of these eyes was significantly related to anatomic outcome category (P less than 0.001). Follow-up data from subsets of eyes at 6 months, 12 months, or 2-5 yr after the initial acuity test suggest that early FPL acuity tests may be predictive of long-term functional outcome (r = 0.75-0.87).     

Cataract surgery in children with and without retinopathy of prematurity

PURPOSE: To report the outcomes of cataract surgery in children born prematurely who had or did not have retinopathy of prematurity (ROP). SETTING: Seoul National University Hospital, Department of Ophthalmology, Seoul, Korea. METHODS: Retrospective studies were conducted by reviewing the charts of 26 eyes of 14 premature infants with or without ROP that had cataract surgery. The patients' preoperative characteristics and postoperative visual outcomes were documented. Cataract surgery consisted of lensectomy, posterior capsulectomy, and anterior vitrectomy in patients younger than 2 years and primary posterior chamber intraocular lens (PC IOL) implantation or secondary PC IOL implantation in those 2 years or older. Postoperative optical correction in those younger than 2 years was by glasses or contact lenses. RESULTS: Eight eyes of 5 patients had acute ROP; 4 eyes had stage 3, 2 had stage 2, and 2 had stage 1. Three eyes had transconjunctival cryotherapy for treatment of threshold ROP. First-eye cataract surgery were performed in children from 0.2 to 5.5 years old (mean 1.5 years) and second-eye surgery, in children from 1.8 to 12.1 years old (mean 4.3 years). Twenty eyes had implantation of a PC IOL. In 1 patient with stage 3+ ROP, Rush (plus) type, both eyes had combined cataract and scleral buckle encircling surgery. The mean follow-up after the last surgery was 1.4 years (0.5 to 3.1 years). At the last examination, the best corrected visual acuity was good fixation or better than 20/80 except in 2 eyes, 1 with esotropia and the other with a dense pupillary membrane. CONCLUSIONS: This is the first report of an encouraging surgical outcome for PC IOL implantation in premature infants with cataract regardless of the presence of ROP. However, if retinopathy is present and has progressed in the cataractous eye of a premature child, careful examination and timely surgical decisions are important.