Strabismus in premature infants in the first year of life. Cryotherapy for Retinopathy of Prematurity Cooperative Group.

OBJECTIVES: To present the 3- and 12-month strabismus data from 3030 premature infants with birth weights less than 1251 g enrolled in the Multicenter Trial of Cryotherapy for Retinopathy of Prematurity. DESIGN: Data from the 3- and 12-month examinations conducted at 23 regional study centers were tabulated for all infants. The main outcome measure, ocular motility, was compared with baseline demographic variables and retinopathy of prematurity severity for the worse eye. Findings at 3 months were compared with the incidence of strabismus at 12 months. RESULTS: At 3 months, 200 (6.6%) of the 3030 infants were strabismic. In the 2449 infants examined at both time points, 289 (11.8%) were found to have strabismus at 12 months. Retinopathy of prematurity was significant for strabismus at both 3 and 12 months (P<.001). The presence of strabismus at 3 months was found to be a highly significant predictor of strabismus at 12 months. Anisometropia, abnormal fixation, and unfavorable retinal structure also were significant predictors of strabismus at 1 year. The total prevalence of strabismus in the first year of life was 14.7%. CONCLUSION: The presence of acute-phase retinopathy of prematurity places the premature infant at increased risk for strabismus.

A comparison of cryotherapy versus diode laser retinopexy in 100 consecutive infants treated for threshold retinopathy of prematurity.

PURPOSE: The purpose of this paper is to present a series of patients who were treated for threshold retinopathy of prematurity with either cryotherapy or diode laser. Complications and unfavorable outcomes during the first year after treatment will be compared for the two procedures. METHODS: The clinical courses of a consecutive series of 100 infants (192 eyes) were reviewed. All infants had their threshold status confirmed by a second examiner. Infants were treated with cryotherapy through 1993 and with diode laser thereafter. One hundred two eyes of 54 patients were treated with cryotherapy. Ninety eyes of 46 patients were treated with laser retinopexy. Two of the patients who were treated with laser (4 eyes) did not survive to the 3-month follow-up visit, and their results are not included here. The two groups of infants were comparable in their birth weight, adjusted gestational age at treatment, and severity of disease as determined by zone and sectors of stage 3 retinopathy of prematurity. RESULTS: Unfavorable outcome (total retinal detachment) was seen in 25.4% of eyes treated with cryotherapy (26 of 102), as compared with 15% of eyes treated with laser (13 of 86). Two cataracts were seen in our patients: one patient 22 weeks after cryotherapy, and the other 7 months after diode laser. CONCLUSIONS: No statistically significant difference was found in the rate of retinal detachments in the two groups (X2 = 3.05; P = .08).

Retinopathy of prematurity in discordant twins.

Discordant twins may be at increased risk for retinopathy of prematurity (ROP) because of factors related to their unequal growth. Discordancy is defined as a difference of 15% or more in the birth weights of the two infants. We examined the data in 26 sets of discordant twins from six NICUs, including birthweight, gestational age, sex, and highest grade of ROP. Thirty-eight percent (10) of the lower birthweight infants had higher grades of ROP than their twin. Twenty-three percent (6) of the heavier birthweight twins had higher grades of ROP than their smaller siblings. Three infants reached threshold, and five were prethreshold. In every case, their twin siblings had mild or no ROP. Thirty-eight percent of the twins (10) had the same ROP outcome.

Clinical assessment of visual function in the young child: a prospective study of binocular vision.

Binocular vision was evaluated in 12 children with infantile esotropia before and after corrective surgery. Stereopsis was measured by the eye movement/global stereopsis method. Also in a subgroup of four infants, binocular and monocular pattern VERs were recorded to evaluate binocular summation. Results revealed 50% of the infantile esotropia children who had corrective surgery before one year of life developed gross stereopsis two weeks following surgery. In addition, of four infants who showed no evidence of stereopsis, 50% showed some degree of binocular summation following surgery. The importance of prospective studies of binocular vision in infantile esotropia is discussed within the context of new tests that can be used to objectively assess binocularity in the preverbal child.

Visual acuities in infants with congenital cataracts operated on prior to 6 months of age.

Seven infants with complete bilateral cataracts were operated on and fitted with extended-wear silicone contact lenses. The infants were matched to 16 normal control subjects. A modified preferential looking technique was used to assess visual acuity; the Bayley Scale of infant Development was administered to measure psychological development. Of the seven infants with cataracts, those operated on prior to 8 weeks of age seemed to have normally developing vision. All others showed a substantial visual lag when compared with the control group. Bayley scores for infants operated on early (before 8 weeks) fell within the range of normal variability. The infants operated on later demonstrated a statistically significant lag in development. Also, a pendular nystagmus was noted in those infants with cataracts who were operated on later.