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At least 127 records · Page 7Linked to original sources

Color doppler imaging of the central retinal artery in premature infants undergoing examination for retinopathy of prematurity.

PURPOSE: Recent attempts have been made to quantify blood flow velocity in the central retinal artery (CRA) of adults using color Doppler imaging (CDI). Although retinal vascular abnormalities are the hallmark of severe retinopathy of prematurity (ROP), normal values have not been established for CRA blood flow velocity in premature infants. METHODS: CDI of the CRA was successfully performed on 43 eyes in 22 infants (postconceptional ages 32 to 39 weeks) before the infants underwent examination for ROP. Peak systolic velocity (PSV) and end diastolic velocity were recorded from at least 1 eye of each patient. Pourcelot's resistive index was then calculated for each eye studied. RESULTS: Mean PSV for patients with no ROP (n = 6) was 7.2 +/- 1.5 cm/s, whereas those with any degree of ROP excluding plus disease (n = 9) had a mean PSV of 8.9 +/- 1.8 cm/s. Of the patients with ROP and plus disease (n = 7), the mean PSV was 7.0 +/- 1.6 cm/s. There were no statistically significant differences among these 3 groups (P= .08). CONCLUSIONS: CDI can be successfully performed on preterm infants and yields values lower than those previously reported in healthy adult subjects. PSV in the CRA may be higher in subjects with ROP in the absence of plus disease; however, further study is needed to determine whether these differences are significant.

Blood Flow Velocity↗

Study of neurotransmitters in premature infants with or without apnea of prematurity.

Twelve-hour urinary excretion of 4-hydroxy-3-methoxymandelic acid (VMA), homovanillic acid (HVA), and 3-methoxy-4-hydroxyphenylglycol (MHPG) was studied in 20 premature infants, 8 without apnea and 12 with apnea. All infants were studied at 1-3 days of postnatal age (before apnea). Nonapneic infants were restudied at 10-15 days of postnatal age. Apneic infants were also restudied 24 h after apnea. Apnea was not associated with decreased urinary excretion of VMA and MHPG. Only HVA, when expressed as microgram/kg body weight, was significantly lower after the onset of apnea. This difference disappeared when HVA was expressed as microgram/mg creatinine. We suggest that apnea of prematurity may not be related to the immaturity of catecholamine pathways.

Apnea↗

Some risk factors for cerebral palsy in very premature infants: importance of premature rupture of membranes and monochorionic twin placentation.

OBJECTIVE: To delineate the perinatal risk factors of neurodevelopmental disabilities in very preterm birth applying logistic regression analysis. DESIGN: This prospective, geographically defined collaborative study was carried out in the Franche-Comté region of France. SUBJECTS: From October 1, 1990 to September 30, 1992, perinatal and follow-up data were collected on 203 consecutive live-born singleton or twin non-malformed infants with strictly ascertained gestational ages of less than 33 weeks. MAIN OUTCOME MEASURE: The rate of cerebral palsy and/or severe mental retardation as diagnosed by a family physician or pediatrician with a screening-skill test performed at 2 years of age. RESULTS: 167/171 (98%) survivors were evaluated. Twenty-two of the 167 examined infants (13%) showed signs of cerebral palsy, and 10 of these had severe cerebral palsy or mental retardation. Risk factors for disabilities were selected by a multivariate approach: premature rupture of membranes >/=48 h (OR 4.3, 95% CI 1.6-11.8); monochorionic twin placentation (OR 6.0, 95% CI 1.7-21.3), and respiratory distress syndrome (OR 2.8, 95% CI 1.1-7.1). CONCLUSION: This geographically defined prospective study gives epidemiological data and highly suggests that there is a link between prenatal events (premature rupture of membranes, monochorionic twin placentation), postnatal events (respiratory distress syndrome), and neurological disabilities in former preterm infants.

Birth Weight↗

Retinopathy of prematurity and other ocular problems in premature infants weighing less than 1500 g at birth.

PURPOSE: To estimate the incidence of retinopathy of prematurity and other ocular problems in a population of preterm infants. METHODS: This retrospective study included all infants with gestational age (GA) <32 weeks and birth weight (BW) <1500 g cared for in the neonatal intensive care unit (NICU) over a period of nine years (1992-2000). Ophthalmological examination was started the 4th week of life and included refractive examination, examination of the cornea and funduscopy under mydriasis. An ocular motility test was done after the 2nd month. RESULTS: The study included 194 infants. Stage I and II retinopathy occurred in 51 infants but regressed spontaneously. Five of the 194 (2.5%) had to undergo cryopexy. Optic disc atrophy was observed in association with peri-intraventricular hemorrhage (PIIVH) (grade IV) in seven infants. Fifteen infants (7.7%) had retinal hemorrhages which were absorbed by three months of age. Almost 20% of the study infants developed high refractive errors and 13.4% strabismus. CONCLUSIONS: Not only retinopathy of prematurity, but other serious ocular problems were observed in this population of preterm infants. The role of PIIVH III-IV in the pathogenesis of certain ocular problems needs further elucidation.

Cryosurgery↗

Efficacy of topical anesthetics to reduce pain in premature infants during eye examinations for retinopathy of prematurity.

BACKGROUND: Eye examinations for retinopathy of prematurity (ROP) are stressful and probably painful, but many ophthalmologists do not apply topical anesthetics because their efficacy in reducing pain has not been established. OBJECTIVE: To evaluate the potential benefits of topical anesthetic eye drops in reducing pain during neonatal eye examination for ROP. METHODS: Neonates born at < or =30 weeks' gestation and expected to have at least 2 examinations for ROP were included. Patients were randomly assigned to receive either proparacaine HCl ophthalmic solution 0.5% or NaCl 0.9% (saline) eye drops prior to an eye examination. In a subsequent examination, each patient received the alternate treatment. Eye drops were prepared in the pharmacy in identical tuberculin syringes, and physicians, nurses, and pharmacists were blinded to the treatment given. Pain was measured using a scoring system with both physical and physiologic measures of pain (Premature Infant Pain Profile [PIPP], possible range 1-21), which has been validated in preterm infants. PIPP scoring was performed simultaneously by 2 nurses: 1 and 5 minutes before and after the eye examination and during initial placement of the eye speculum. The same ophthalmologist performed all examinations. RESULTS: Twenty-two patients were studied, with 11 infants receiving proparacaine and 11 receiving saline as the first treatment. Crossover was performed with a median of 17.5 days between treatments. Patients experienced significantly less pain at speculum insertion with proparacaine than with saline (paired difference -2.5 +/- 3.4; p = 0.001). CONCLUSIONS: Topical anesthetic pretreatment reduces the pain response to eye examination for ROP and should become routine practice. Because this is not effective in all infants, additional measures to reduce pain should be taken.

Administration, Topical↗

[C-reactive protein in the maternal serum and risk of maternal infection in premature rupture of the fetal membranes and threatened premature labor].

For diagnosis of ascending intra-uterine infections, regular controls of the serum CRP levels were carried out in 129 patients with premature rupture of membranes and impending premature labour. The height of the maternal CRP level and the simultaneously determined leucocyte counts and band counts were compared with the peripartal fever morbidity (intrapartal fever, puerperal fever). It was established that patients who had a prepartal CRP level of 10 mg/l or more suffered febrile complications more frequently (fever morbidity 18.2%) than females in whom such high CRP values did not occur (fever morbidity 3.4%). Similar correlations existed between the other parameters tested and the fever morbidity, and subclinical intrauterine infections were recognized with higher reliability if CRP, leucocyte count and band count had been determined in combination.

C-Reactive Protein↗

[C-reactive protein in the maternal serum and risk of fetal infection in premature rupture of the fetal membranes and threatened premature labor].

In order to find out whether, in the framework of our obstetrical management, determinations of the C-creative protein (CRP) in maternal serum enables recognition of incipient intra-uterine infections, regular controls of the CRP level were performed in 129 patients with premature rupture of membranes and impending premature labour. The maternal CRP levels and the simultaneously determined total leukocyte counts and band counts were compared with the frequency of neonatal infectious diseases up to the 3rd day of life. None of the infants were affected whose mothers never had values above 10.0 mg/l. If he maternal CRP values exceeded the 10.0 mg/l limit, then 6.3%-57.1% of the newborns were affected depending on their birth weight. Therefore, the prepartal CRP diagnosis can, especially in infants with low birth weight, help to determine the risk of infection.

C-Reactive Protein↗

Perinatal intracranial hemorrhage and retinopathy of prematurity: currently nonpreventable complications of premature birth?

There is now considerable evidence that the control of cerebral circulation in sick small infants is sometimes seriously deranged and subject to wide fluctuations during neonatal care. Our current preoccupation with looking at oxygen administration and peripheral arterial oxygen tensions as the only cause of ROP is not likely to be productive. Until we know more about the causes of cerebral blood flow fluctuation, IVH, asphyxia, and their effects on the retinal circulation, we are not apt to make much progress. There is a strong association between retinopathy and IVH in premature infants. With our current knowledge, we are unable to prevent or to treat either IVH or ROP. The public should be better informed that both of these conditions are usually unavoidable complications of premature birth.

Asphyxia Neonatorum↗

Visual acuity, strabismus, and amblyopia in premature babies with and without retinopathy of prematurity.

One hundred eighty-seven premature babies, 48 of whom suffered from retinopathy of prematurity (ROP), were examined. A higher incidence of strabismus was found in the group with cicatricial ROP (23% vs. 9%). Amblyopia was present in 6% of the ROP group and in only 1.4% of babies without ROP. Myopia was found in 50% of the ROP group as compared with 15% in the nonROP group. Astigmatism and anisometropia were more common in the ROP group, but hypermetropia was equally represented in both groups.

Age Factors↗

[Relationship between premature labor and maternal age, as well as between premature labor and parity].

Various publications of the last years and own studies, too demonstrate that birth rank and maternal age, as well, in each case independently influence the risk of prematurity. The rate of prematurity for primiparous and multiparous women is above the average; it is just the same for very young and comparatively old women. Basing on a review of literature eventual causes are briefly discussed.

Female↗

[Brain damage in relation to occurrence of retinopathy of prematurity. A regional ophthalmologic follow up of premature infants born 1982-1984].

Regular ophthalmic surveillance started in 1982 for all surviving prematures in Frederiksborg County considered at risk of developing retinopathy of prematurity (ROP). During 1982-1984 185 infants of gestational age 25-35 weeks at delivery were examined; blindness eventually appeared in four out of the 28 who showed some stage of ROP. All 28 attended ophthalmic reassessment at age 7-10 years and were compared with 60 of the same cohort without evidence of ROP. At follow-up (n = 88) there was evidence of psychomotor disturbances in 45 children, manifesting as major CNS damage in 21, and minor in 24. With correction for drop-outs the regional frequency of severe CNS damage (mainly cerebral palsy and mental retardation) was 29.6% for gestational ages < 32 weeks at delivery and 24% as calculated for birth weights < 1500 g. An analysis of perinatal factors based mainly on matched pairs did not indicate any definite association with subsequent damage to eye or brain, and statistically there was no association between severity of ROP and CNS impairment. We have no explanation for the high frequency of CNS impairment at follow-up.

Brain Damage, Chronic↗

An international classification of retinopathy of prematurity. The Committee for the Classification of Retinopathy of Prematurity.

Because of modern life-support systems capable of keeping tiny premature infants alive, retinopathy of prematurity has recurred. No classification system currently available adequately describes the observations of the disease being made today. A new classification system, the work of 23 ophthalmologists from 11 countries, is presented in an attempt to meet this need. It emphasizes the location and the extent of the disease in the retina as well as its stages. The term "plus" is employed with the stage to denote progressive vascular incompetence. A computer-compatible diagram for recording the results of the examination employing the new classification system is furnished.

Humans↗

The correlation of visual function with posterior retinal structure in severe retinopathy of prematurity. Cryotherapy for Retinopathy of Prematurity Cooperative Group.

The Multicenter Trial of Cryotherapy for Retinopathy of Prematurity previously reported reduced incidence of both poor structural and functional outcomes after cryotherapy. We compared the results in 304 eyes of patients in the randomized portion of the trial in whom both structural and functional assessments were performed 12 months after randomization. Two hundred fifty-five eyes (83.9%) had concordant outcomes: 153 eyes had favorable structural and functional outcomes and 102 eyes had unfavorable structural and functional outcomes. Twenty-nine eyes (9.5%) had discordant outcomes: 20 eyes had favorable structural and unfavorable functional outcomes and nine eyes had unfavorable structural and favorable functional outcomes. The small number of discordant outcomes could generally be accounted for by three factors: (1) retinal abnormalities beyond those considered in the photographic grading system (12 eyes), (2) nonretinal visual pathway disease (five eyes), or (3) false-positive and false-negative results in the measurement systems used to evaluate structure and function (five eyes). In 20 eyes (6.6%), photographs could not be graded or the visual acuity was untestable. We conclude that the appearance of the posterior pole of the eye correlates well with grating acuity in the 12-month-old infant with a history of severe retinopathy of prematurity.

Cryosurgery↗

Prediction of visual function in eyes with mild to moderate posterior pole residua of retinopathy of prematurity. Cryotherapy for Retinopathy of Prematurity Cooperative Group.

OBJECTIVE: The Multicenter Trial of Cryotherapy for Retinopathy of Prematurity (CRYO-ROP) assigned eyes with macular heterotopia to the "favorable" outcome category and eyes with retinal fold involving the macula to the "unfavorable" outcome category. This binary assignment did not agree well with measured visual acuity outcome. We tested the hypothesis that rating structural outcome on a continuum from less to more severe would improve prediction of visual acuity in eyes with macular heterotopia or retinal fold. DESIGN: Fundus photographs of the 69 eyes in the CRYO-ROP trial that had macular heterotopia (n = 55) or retinal fold (n = 14) at the 1-year follow-up were analyzed for severity of macular heterotopia, macular elevation, and pigmentary disturbances. Each physician author estimated each eye's predicted Snellen acuity, based on the photographic findings and clinical expertise. These results were compared with the grating acuity obtained at ages 1 and 3 1/2 years with the Teller Acuity Card procedure and with letter acuity obtained at age 3 1/2 years with the crowded HOTV test. PATIENTS: The 69 eyes were from 59 patients in the randomized portion of the CRYO-ROP trial. RESULTS: Although eyes with retinal fold tended to have greater visual impairment than eyes with macular heterotopia, there was a wide variation in acuity in both groups, and physicians were unable to predict visual acuity from retinal appearance. CONCLUSION: The physician cannot reliably predict either grating acuity or letter acuity in eyes with macular heterotopia or macular fold due to retinopathy of prematurity. There is no substitute for periodic visual acuity testing in these eyes.

Child, Preschool↗

Retinopathy of prematurity. Risk factors in a five-year cohort of critically ill premature neonates.

We studied the importance of exposure to an elevated partial pressure of carbon dioxide (PCO2) in the development of scarring retinopathy of prematurity (SROP) in a cohort of 92 neonates with chronic lung disease (greater than or equal to 14 days of respiratory therapy, greater than or equal to 30 days of oxygen therapy, and greater than or equal to 70 days in the hospital), 31 of whom had SROP. This cohort was chosen to avoid confounding prolonged respiratory failure with the presence of SROP and because such a cohort was expected to contain approximately 85% of all patients with SROP. Patients with SROP had a lower PCO2 and spent more time on a respirator at higher respirator pressures during the first 70 days of life. In addition, infants with SROP had a lower mean arterial pressure and had a higher prevalence of seizures (97% vs 43%) and intraventricular hemorrhage (52% vs 26%). We conclude that an elevated PCO2 is not associated with SROP in this group of critically ill premature neonates but that the presence of a seizure disorder or an intraventricular hemorrhage is strongly associated with SROP.

Blood Pressure↗

Growth and phosphorus metabolism in premature infants fed human milk, fortified human milk, or special premature formula. Use of serum procollagen as a marker of growth.

Human milk promotes less than optimal growth and is associated with phosphorus deficiency and decreased bone mineralization in very-low-birth-weight (VLBW) infants. In this study, the effects of feeding premature infants either human milk (HM), fortified human milk (FHM), or special premature formula (Similac Special Care [SSC]) on growth, phosphorus metabolism, and serum type I procollagen (pColl-I-C) were evaluated. Infants fed FHM exhibited a rate of weight gain and an increase in head circumference comparable with infants fed SSC and significantly greater than infants fed HM, despite the fact that both the FHM group and the HM group demonstrated biochemical evidence of phosphorus deficiency. The pColl-I-C concentrations in VLBW infants were tenfold to 20-fold greater than concentrations in normal children older than 2 years of age. The pColl-I-C levels correlated positively with weight gain and were significantly greater in the FHM and SSC groups than in the HM group. By contrast, serum alkaline phosphatase levels did not correlate with weight gain and were significantly lower in the rapidly growing SSC group than in either of the two groups with phosphorus deficiency and presumed poor bone mineralization. We conclude that the serum pColl-I-C concentration is a biochemical marker of growth in VLBW infants and may prove useful as a predictor of growth responses to various nutritional and therapeutic interventions.

Blood Proteins↗

Do growth-retarded premature infants have different rates of perinatal morbidity and mortality than appropriately grown premature infants?

OBJECTIVE: To determine if perinatal morbidity and mortality differ in growth-retarded, small for gestational age (SGA), premature infants and appropriate for gestational age (AGA) infants. METHODS: All consecutive, singleton, nondiabetic, preterm pregnancies delivered over a 15-year period were analyzed. Infants were categorized as SGA (at or below the tenth percentile) or AGA (11th to the 89th percentiles), then stratified by birth weight and gestational age categories. Perinatal morbidity and mortality were examined. RESULTS: We studied 4183 preterm deliveries, 1012 of them SGA and 3171 of them AGA. Overall, we found significantly higher rates of fetal and neonatal death in the SGA group. Stratification by gestational age revealed significantly higher rates of neonatal death for the SGA group compared with the AGA group in each gestational age category. Overall, comparison also revealed significantly higher rates of fetal heart rate abnormality in the SGA group but no difference in neonatal sepsis, birth trauma, cesarean delivery, hyaline membrane disease, or congenital anomalies. CONCLUSION: Growth-retarded premature infants have a significantly higher risk of morbidity and mortality, both before and after delivery, than do appropriately grown infants.

Confidence Intervals↗

Operational aspects of terminating randomization in the Multicenter Trial of Cryotherapy for Retinopathy of Prematurity. Cryotherapy for Retinopathy of Prematurity Cooperative Group.

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 date 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.

Blindness↗