Eyes Of Infants Research Articles

The Eye in Infancy

General considerations vision in infants - developing and testing congenital malformations evident in the first year of life retinopathy of prematurity acquired disorders of the infant eye the infant eye in systemic disease.

Mapping of Fc gamma receptors in the human and porcine eye

By using an immunohistochemical technique, we detected a strong reaction product for Fc gamma receptors in the keratoconjunctival epithelium, uveal trabecular meshwork, optic nerve, and muscle walls of the retinal and ciliary vessels of infant human eyes; moderate staining was seen on the corneal endothelium, corneoscleral trabecular meshwork, non-pigmented ciliary epithelium, ciliary muscle fibers, endothelial lining of ocular blood vessels, as well as the anterior region of Muller cells, the outer nuclear layer, and pigment epithelium of the retina. In aged human and porcine eyes, the same structures stained somewhat less intensely than did those in infant human tissues. Primary cultures of porcine trabecular cells demonstrated a more intense immunoreaction product than did tertiary cultures. We discuss the possible role of Fc gamma receptors in various ocular inflammatory conditions and the implications of age-dependent expression by human trabecular cells in the pathogenesis of open-angle glaucoma.

Isolation of Chlamydia trachomatis from amniotic fluid

A 26-year-old white woman had premature rupture of membranes at 35 weeks' gestation. Cervical specimens initially demonstrated group B streptococci and Chlamydia trachomatis. Amniocentesis was performed and the amniotic fluid was positive for chlamydia by direct fluorescent antibody stain. The Gram stain was negative. The patient had an elevated white blood cell count. Labor was induced because of suspected chorioamnionitis. A 2120-g female infant was delivered with an Apgar score of 9 at 1 and 5 minutes. The infant's eye and nasopharyngeal specimens were positive for chlamydia by direct fluorescent antibody stain. After delivery, both Ureaplasma urealyticum and C trachomatis were isolated from the amniotic fluid and fetal membranes. This is the first reported case of chlamydial isolation in amniotic fluid.

Operational aspects of terminating randomization in the multicenter trial of cryotherapy for retinopathy of prematurity

The Multicenter Trial of Cryotherapy for Retinopathy of Prematurity (CRYO-ROP) is a randomized clinical trial sponsored by the National Eye Institute (NEI) designed to test whether cryotherapy applied to eyes of premature infants with a specified extent of stage 3+ ROP significantly decreases the incidence of an unfavorable outcome. An unfavorable outcome is defined as either retinal detachment or a retinal fold and was determined at 3 months posttreatment by the use of a masked photographic system. Enrollment into the trial was terminated on recommendation of the Data and Safety Monitoring Committee 9 months before the scheduled closing data for enrollment because of demonstrated treatment benefit. The purpose of this article is to discuss the operations involved in the orderly termination of enrollment and dissemination of results from this trial. These activities included preparation of trial participants and staff, release of trial information, continuing patient care, data collection and coding, and publication of trial results.

The quantity of rhodopsin in young human eyes

The rhodopsin content of 20 eyes of infants and children ages 27 weeks gestation to 8 years (11 donors) was assayed and compared to the rhodopsin content of adults (36 eyes; 19 donors). Infants have significantly lower rhodopsin contents than adults. On average the rhodopsin content of young infants is about a third of adults. Previously reported full-field b-wave sensitivity of young infants is about 0.5 log units, that is about a third, less than adults. Thus, as previously found in infant rats, photon capture by rhodopsin appears to limit the dark adapted sensitivity of young human infants.

Posterior Chamber Lens Implantation in Infants and Juveniles

Extracapsular cataract extraction with posterior chamber intraocular lens implantation was performed in 23 eyes (21 patients) of infants and juveniles. Four children with unilateral infantile cataract were operated on at the age of 3 or younger. Nine older children (11 eyes), all of them with bilateral juvenile cataract, were operated when older than 3. Seven children had traumatic cataracts: surgery was performed at the age of 3 or younger in three of them, and above this age in four. One patient aged 13 had a cataract due to heterochromic iridocyclitis. Final visual acuity results, binocularity, surgical complications and the need for additional surgery for secondary cataract development were analysed in relation to the age at surgery and the type of cataract. A visual acuity of 6/12 or better was achieved in 82.6% of the operated eyes. Stereopsis was found in 47.6% of the patients. Inflammation with fibrinous exudate, aqueous flare and cells in the anterior chamber appeared postoperatively in 57% of eyes, and were more common among the infant age group, but subsided with suitable anti-inflammatory treatment. Opacification of the posterior capsule was found within 3 months of surgery in 43.5% of the eyes, and was more common in the infants. Treatment with Nd-YAG laser was useful in the older children; in infants the opening made by laser in the posterior capsule did not last and a clear visual axis was achieved only after pars plana anterior vitrectomy and posterior central capsulectomy. The final results were excellent in patients with juvenile and traumatic cataracts. In those with unilateral infantile cataracts the results were considered encouraging.

Reduced Incidental Light Exposure: Effect on the Development of Retinopathy of Prematurity in Low Birth Weight Infants

In a recent study, it was reported that incidental lighting within the newborn intensive care unit setting may play a role in the development of retinopathy of prematurity. Consequently, the routine clinical management in the intensive care nursery at Yale-New Haven Hospital was modified to include shielding each premature infant's isolette, thereby decreasing the intensity of the nursery lights on an infant's eyes from a median light level of 55 foot-candles to 15 foot-candles. The effect of this reduction of light level on the incidence of retinopathy of prematurity in 161 premature infants was prospectively investigated. This group was then compared with a historic control group of 129 premature infants with similar characteristics who had been exposed to standard nursery lighting. There was no difference in the incidence and severity of retinopathy of prematurity between the two groups.

Halt called to infant eye tests

Halt called to infant eye tests

Expectation and Anticipation of Dynamic Visual Events by 3.5-Month-Old Babies

We report an investigation of the development of visual expectancies in 3.5-month-old infants. One of the infant's eyes was videorecorded as the infant watched a series of slides that were presented noncontingent on behavior. Babies were presented an alternating and an irregular series of 30 slides with a 700-msec onset duration separated by an interstimulus interval (ISI). The ISI for the alternating series was 1,100 msec, whereas the slides for the irregular series were separated by 900, 1,100, or 1,300 msec, randomly ordered. One-half of the babies saw the irregular series first, and one-half saw the regular series first. Babies in both groups provided evidence that they developed expectations for the visual events in the alternating series. Their reaction times (RTs) declined significantly from 3-5 "baseline" presentations, and their RTs were reliably faster during the alternating than the irregular series. Additionally, babies in the alternating-late group had significantly more stimulus anticipations during the alternating than during the irregular series. These findings indicate that 3.5-month-olds can detect regularity in a spatiotemporal series, will develop expectancies for events in the series, and will act on the basis of those expectancies even when those actions have no effect on the stimulus events. We believe that infants are motivated to develop expectations for noncontrollable spatiotemporal events, because these expectations permit them to bring their visual behavior under partial internal control.

First Conversations

Conversations of 48 mothers were recorded with audiotapes while they interacted with their newborn infants in the first 10 minutes after birth in an El Paso, Texas, birth center. Of the women recorded, 34 were Hispanic; 14 were Anglo. Analysis of verbal content revealed that, unlike previously reported studies, comments about the infant's eyes or resemblance to family members were rare or lacking entirely. Far more frequent than reported by others were questions or comments about the infant's gender. It is postulated that differences in verbal content among studies of these first "conversations" may be due to (1) different time intervals for recording or (2) different sociocultural backgrounds of the women observed (mother-infant interaction, language, and ethnicity).

Grooming with a stone in sooty mangabeys (Cercocebus atys)

"Stone-grooming," or grooming with a stone, has been reported in Macaca fuscata. This report provides a descriptive account of a similar behavior displayed by a female mangabey Cercocebus atys. During a study of embracing behavior in sooty mangabeys, one adult female was observed to groom her infant with a stone. The grooming pattern involved short strokes and/or a circular motion over the area being groomed-the infant's eye region. Stone-grooming appears to be a distinct type of grooming although the function(s) of this behavior remains unclear. The use of a stone in grooming may represent a case of tool use.

Light transmission of phototherapy eyeshields.

Twelve types of phototherapy eyeshields showed peak light transmission of less than 0.1%, and none transmitted greater than 0.04% light in the 460 nm spectral region. Commercial eyeshields offered no advantage over locally made ones. The choice of shield may be less important than how it is secured over the infant's eyes.

An Ultrastructural Study of DNA Precipitation in the Anterior Segment of Eyes with Retinoblastoma

The anterior segment of six infant eyes enucleated for retinoblastoma were studied by light and electron microscopy in an attempt to describe the pattern of DNA precipitation. In only one of these cases was extracellular deposition of DNA in the iris and aqueous outflow pathways detectable by routine light microscopy and Feulgen staining. In two cases, ultrastructural examination was necessary to resolve the presence of small discrete electrondense DNA granules (60–200 nm). In three cases, the DNA deposits were found on the anterior surface of the iris, in the mid-iris stroma around blood vessels, and in the outer layers of the trabecular meshwork around Schlemm's canal. Although the quantity of the material varied in the three cases, the similar pattern of distribution appeared to reflect routes of fluid movement within the eye and sites of permeability barriers at which the passage of larger particulate matter is obstructed. The DNA deposits had an affinity for collagen and basal lamina, especially in the iris. Interestingly, they were not phagocytosed by the trabecular endothelial cells. No DNA could be detected ultrastructurally in the anterior segment of the three remaining eyes also enucleated for retinoblastoma. The authors' findings suggest that DNA deposition in the anterior segment may be a more common phenomenon in retinoblastoma than has been suspected previously from routine histopathologic studies. The findings are discussed in relation to other types of tumor in which DNA coating around blood vessels has been observed. It would appear that tumor necrosis and cell death are crucial factors that may lead to DNA precipitation in a variety of forms.

Mensuration data in infant eyes with unilateral congenital cataracts.

The purpose of this study was to determine the size and shape of infant eyes having a unilateral congenital cataract. Fourteen infants presenting consecutively with a unilateral congenital cataract were studied. Ages ranged from 1.3 to 6 months (mean 3.7 months). Corneal curvature ranged from 43.00 to 49.50 D (mean 45.6 D). Refractive error at the corneal plane ranged from +23.50 to +34.00 D (mean +28.07 D). The axial length ranged from 16.49 to 20.09 mm (mean 18.41 mm). Microcornea was found in eight infants. There was rapid growth in eye size from normal neonatal dimensions. No significant relation was found among the following: corneal curvature and age; refractive error and age; axial length and age or presence of microcornea; and corneal curvature and refractive error. Corneal vault may be an important factor in fitting contact lenses to aphakic infants. Contact lenses for infants should be designed based on the dimensions of the infant eye.

Rearranged Automated Keratometer for Newborn Infants and Patients in the Supine Position

To measure corneal curvature in newborn infants and patients in the supine position, we rearranged an automated keratometer, dividing it into two parts, the power unit and the measuring system. The measuring unit was mounted on a universal stand. We observed no difference in measured value between the sitting and supine positions and no difference in maneuverability. We also examined the effect of a speculum in normal adult subjects in the supine position, in which both the strong and the weak radii and the axis of astigmatism were slightly affected. However, there was no significant difference in the mean values of the strong and weak radii of corneal curvature in 22 eyes of infants with corrected gestational ages of 37 to 43 weeks. The examination was carried out with ease. The mean value of corneal curvature was 7.05 mm and the range was 6.63 to 7.74 mm.

The penetration of detergents into adult and infant eyes: Possible hazards of additives to ophthalmic preparations

In studies of surfactant penetration into the eye, radiolabelled detergent was found to penetrate the rabbit cornea, to accumulate readily in ocular tissues and to be released slowly. Repeated applications led to increasing binding of the detergent. Permeability, ocular and systemic uptake and retention were all greater in juvenile than in adult rabbits. Preliminary tests of the effects of surfactants on ocular cells in vitro using concentrations found in vivo, suggest that some low-level effects might occur, particularly in juveniles.

Risk Factors Associated with Retrolental Fibroplasia

AbstractThe eyes of infants who were premature or had exposure to increased ambient oxygen from 1979 to 1981 were examined. Of 1012 neonates, 19 were found to have acute retrolental fibroplasia (RLF) grade III or worse in at least one eye. Sixteen also had chronic lung disease (CLD), and when compared to 25 control patients who had CLD but not grade III or more RLF, they were found to consistently have lower blood CO2 tensions (PCO2), lower pH values, higher inspired oxygen concentrations (FIO2S) and a higher incidence of seizure disorders (100% vs. 48%). We could not show that an elevated PC02 increased the risk for developing RLF. Infants with either chronic lung disease or chronic lung disease and seizures had a high risk for developing RLF grade III (39% and 57%, respectively).

Formate concentrations in a case of methanol ingestion.

An eight-month-old infant ingested at least 3.5 g of methanol when he accidentally received 5 mL of amoxicillin suspended in 70% methanol. The serum methanol concentration 8 h later was 9.7 mmol/L (310 mg/L) and the formate concentration 23 mmol/L (1.0 g/L). At 18 h after the ingestion, total CO2 had decreased to 6.8 mmol/L. Throughout the second day, 21-32 h after the ingestion, the methanol concentration was 2.8-3.4 mmol/L (90-110 mg/L) and that of formate was 31-33 mmol/L (1.4-1.5 g/L). On the third day, 46 h after the ingestion, methanol was not detected and the formate concentration had declined to 16 mmol/L (720 mg/L). The patient was treated with activated charcoal 7 h after the ingestion and with ethanol, administered both orally and intravenously, 21 h after the ingestion. No abnormalities of the infant's eyes were noted upon ophthalmological examination approximately 55 h after the incident.

Direct Fluorescent Monoclonal Antibody Stain for Rapid Detection of Infant Chlamydia trachomatis Infections

A method of direct fluorescent antibody staining for rapid diagnosis of Chlamydia trachomatis infections in infants is described. This method utilized a fluorescein-conjugated species-specific monoclonal antibody to C trachomatis for detecting chlamydial elementary bodies in smears of the conjunctiva, nasopharynx, oropharynx, anus, and vagina. The sensitivity of direct fluorescent antibody staining was compared with isolation of the organisms in McCoy cells. Thirty-nine infants with purulent conjunctivitis were studied. Diagnosis of C trachomatis conjunctivitis was correctly made by smear in all 16 infants when inflamed eyes were sampled. Positive smears were obtained from 12/14 culture-positive and 4/16 culture-negative nasopharyngeal specimens from infants with chlamydial conjunctivitis. All nasopharyngeal cultures and smears from infants with nonchlamydial conjunctivitis were negative. These results indicate that the direct smear test is a sensitive and specific test for diagnosing C trachomatis infection of the eye and nasopharynx in infants, and this test can be completed within one hour of specimen collection.

Extraocular muscle surgery in early infancy--anatomical factors.

The dimensions and topographical anatomy of 26 eyes from 14 neonates and infants were measured and photographed with special attention to the insertional position of the extraocular muscles. Additional measurements were made in histologic preparations of 12 normal infant eyes. Although the diameters of the neonatal eyes were found to be about 70% of the adult eyes, the volumes of the globes were only about half, and the surface areas even less. The insertions of the rectus muscles were about 2 mm nearer to the cornea than in emmetropic adult eyes, but some were close to or at the equator. The posterior segments of the neonatal eyes were much less developed than the anterior, so that the oblique insertions, as compared to the adult eye, were closer to each other, to the horizontal meridian and to the posterior pole. In some neonatal specimens the inferior oblique insertion was so close to the optic nerve that tenotomy at that point would have jeopardized some of the posterior ciliary vessels and nerves. The dramatic postnatal growth of the eye occurs in the scleral segment; there is minimal corneal growth. About half of the total lifetime increase in the diameters, volume and total surface area of the human eye occurs in the first six months of life. In the six-month-old specimens the volume of the globe and the surface area of the sclera had almost doubled as compared to the neonatal eyes.(ABSTRACT TRUNCATED AT 250 WORDS)