Non-ophthalmologist screening for retinopathy of prematurity.

AIM: To determine if a non-ophthalmologist can accurately screen for retinopathy of prematurity (ROP) by evaluating the posterior pole blood vessels of the retina. ROP is a common ocular disorder of premature infants and may require multiple screening examinations by an ophthalmologist to allow for timely intervention. Since there is a strong correlation between posterior pole vascular abnormalities and vision threatening ROP, screening examinations performed by non-ophthalmologist may yield useful clinical information in high risk infants. METHODS: Infants born at the Medical University of South Carolina who met screening criteria (n = 142) were examined by a single non-ophthalmologist using a direct ophthalmoscope to evaluate the posterior pole blood vessels for abnormalities of the venules and/or arterioles. To determine the accuracy of the non-ophthalmologist's clinical observations, infants were also examined by an ophthalmologist, using an indirect ophthalmoscope, who graded the posterior pole vessels as normal, dilated venules, or dilated and tortuous venules and arterioles (including "plus disease"). RESULTS: There was significant correlation (p <0.001) between the non-ophthalmologist's and ophthalmologist's diagnoses of posterior pole vascular abnormalities. 47 infants had normal posterior pole blood vessels by the non-ophthalmologist examination. Of these, 31 (66%) were considered to have normal vessels and 16 (34%) to have dilated venules by the ophthalmologist. The non-ophthalmologist correctly identified abnormal posterior pole vessels in all 21 infants diagnosed with abnormal arterioles and venules by the ophthalmologist. No infants with clinically important ROP ("prethreshold" or worse) would have failed detection by this screening method. CONCLUSION: Using a direct ophthalmoscope, a non-ophthalmologist can screen premature infants at risk for ROP by evaluating the posterior pole blood vessels of the retina. While not necessarily recommended for routine clinical practice, this technique may nevertheless be of value to those situations where ophthalmological consultation is unavailable or difficult to obtain.

Conversational maxims and scaffolded learning in children with learning disabilities: is the flying buttress a better metaphor?

In our commentary on Stone's (this issue) article on the metaphor of "scaffolding," we propose (somewhat tongue-in-cheek) the "flying buttress" as an improvement. Unlike a scaffold, the buttress symbolizes a nontemporary architectural device that begins as a support to building new knowledge on an existing foundation, but then itself becomes an integral and evolving part of the new structure. We then analyze scaffolded instruction as a kind of conversation that depends on rather sophisticated shared assumptions about the agenda and the rules underlying the process of the conversation, including an understanding of when these rules are suspended. We present evidence that some children with language/learning disabilities may not benefit from scaffolded instruction because they (a) follow a different agenda during instructional discourse (e.g., to camouflage their lack of comprehension); and (b) overrely on the default Gricean Maxims that cooperative speakers always make an effort to be informative, truthful, relevant, and clear.

Retinal examinations in infants after extracorporeal membrane oxygenation.

BACKGROUND: Ophthalmic examinations performed in infants undergoing extracorporeal membrane oxygenation (ECMO) are recommended because ocular abnormalities have been known to occur after this procedure. METHODS: We reviewed medical records of infants treated with ECMO was subsequently underwent routine ophthalmic examination prior to or immediately after hospital discharge. Examinations were performed in a fashion similar to that for retinopathy of prematurity screening. RESULTS: Eye examinations were recorded for 171 patients (342 eyes). Fundus examination was normal in 302 eyes (88%). Abnormal retinovascular findings such as venous dilation or intraretinal hemorrhages, when present, were not considered vision threatening and required no treatment. CONCLUSION: Clinically important retinal findings were not identified in our patients undergoing postECMO screening. Routine dilated fundus examination is probably not cost effective and places additional and potentially unnecessary stress on these infants.

Racial variation in retinopathy of prematurity. The Cryotherapy for Retinopathy of Prematurity Cooperative Group.

OBJECTIVES: To determine and compare the incidence of severe, vision-threatening retinopathy of prematurity (ROP) in black and white low-birth-weight infants. DESIGN: Prospective cohort study. SETTING: Seventy neonatal intensive care units in 23 US participating centers in the Multicenter Trial of Cryotherapy for Retinopathy of Prematurity. PATIENTS: A total of 4099 premature infants weighing less than 1251 g at birth were enrolled to evaluate the natural history of ROP. This 'Natural History' cohort included 2158 white infants and 1584 black infants who were followed up prospectively according to a Natural History protocol. MAIN OUTCOME MEASURES: Incidence and severity of acute ROP. RESULTS: While ROP occurred with similar frequency in all racial subgroups, severe ROP was less common in black infants. One hundred sixty (7.4%) of 2158 white infants reached threshold ROP (defined as at least 5 contiguous or 8 cumulative clock-hours of stage 3 retinopathy in zone 1 or zone 2 in the presence of "plus disease" [dilation and tortuosity of the posterior pole blood vessels]), but only 51 (3.2%) of 1584 black infants progressed to threshold ROP. Using multiple logistic regression analysis, race emerged as a highly significant factor (P < .001) in the development of threshold disease, even when birth weight, gestational age status at delivery, sex, multiple births, and transport status were considered. CONCLUSIONS: Severe, vision-threatening ROP occurs with greater frequency in low-birth-weight white infants than in low-birth-weight black infants who are seemingly at equivalent risk. The reason for this disparity is unknown. We speculate that differences in retinal pigmentation may confer relative protection against free radical-mediated phototoxic injury in black infants.

Retinal vascular endothelial growth factor (VEGF) mRNA expression is altered in relation to neovascularization in oxygen induced retinopathy.

The temporal and spatial expression of vascular endothelial cell growth factor (VEGF) mRNA was studied in normal developing cat retina, and in oxygen induced retinopathy. Unexposed control and oxygen-exposed animals (80 h of 80% oxygen from day 3, n = 16) were studied at 1, 2, 4, and 6 weeks after birth. India ink injected retinal flat mounts were used to study vessel progression, and in situ hybridizations using retinal cross sections were used to assess VEGF mRNA accumulation. In controls, as the retina matured, VEGF mRNA hybridization was evident in the ganglion cell layer in a scattered line of distinct cells prior to the ingrowth of vessels, involved the most cells in regions just peripheral to invading vessels and persisted in a fewer positive cells, widely spaced in the vascularized retinas of control, six week animals. In the inner nuclear layer, hybridization initially appeared diffusely and later became localized to a narrow portion of that layer and persisted there. In animals with oxygen induced retinopathy, a substantial increase in hybridization was observed in both the ganglion cell and inner nuclear layers of the avascular retina anterior to the advancing neovascularization. VEGF hybridization decreased abruptly to background levels in both layers at the point were neovascularization met avascular retina. By six weeks, when the neovascularization reached the ora, there was a return of VEGF mRNA in the inner nuclear layer which was similar to normal control expression. A low level of unchanging expression was also observed in the retinal pigment epithelium in both groups at all ages. These results indicate that VEGF mRNA abundance is regulated during retinal vascularization and is increased in relation to oxygen induced neovascularization, suggesting that VEGF may play an important role in both normal retinal vessel development and in the pathophysiology of retinopathy of prematurity.

A semipermeable skin dressing for extremely low birth weight infants.

Skin breakdown and high fluid requirements are common problems in extremely low birth weight infants that may be reduced by application of a semipermeable skin dressing (SPD). An SPD was applied to 39 study infants who weighed < 1000 gm (control subjects, n = 37) to determine whether it would protect the skin and decrease fluid requirements. Randomization occurred before 12 hours of life and SPD was applied to the chest, abdomen, and back. Sixty-one infants survived the first 14 days. Skin remained nonerythematous, intact, and undamaged under the dressing, whereas uncovered skin sustained significant breakdown in both groups. No significant differences were found in fluid or electrolyte status. Although the SPD did not affect fluid requirements, the significant improvement in skin integrity under the SPD may justify its use in premature infants with delicate skin.

Conversational interactions of mothers and their preschool children who had been born preterm.

This study examined the conversational interactions of mothers and their 4.5-year-old children, who had been born preterm, during a social problem-solving task asking each dyad to agree on the choice of a snack. Relative to comparison mothers, mothers of preterm children seemed to approach the task as a vocabulary lesson; they produced less complex sentences and were more likely to name the snacks and to test their children's knowledge of snack names. Comparison mothers were more likely to focus on the social negotiation aspect of the task, by offering more opinions and reasons. Discussed is whether the conversational strategies of mothers of preterm children reflect appropriate "fine-tuning" or a lag in adjusting to their children's emerging language skills because of a lingering "prematurity stereotype."

Can non-ophthalmologists screen for retinopathy of prematurity?

BACKGROUND: Dilation and tortuosity of the posterior pole vessels ("plus disease") is a poor prognostic sign and may indicate the presence of threshold or pre-threshold retinopathy of prematurity (ROP). Because stage 3 ROP appears rarely in the absence of posterior pole vascular abnormalities, we prospectively evaluated the ability of non-ophthalmologists (4th-year medical students, pediatric residents, and nurse practitioners) to identify abnormalities in the retinal blood vessels of infants undergoing examinations for ROP. METHODS: Fifty infants weighting less than 1600 g at birth were examined between 32 and 40 weeks after conception. Prior to ophthalmological examination, non-ophthalmologist examiners graded posterior pole vessels as normal or abnormal based on ophthalmoscopic appearance. One hundred twenty-one ocular examinations were performed using the teaching mirror of the indirect ophthalmoscope, 179 using the direct ophthalmoscope. The indirect ophthalmoscopy was performed simultaneously by an ophthalmologist who evaluated the posterior pole vessels for abnormalities prior to conducting a peripheral fundus examination on either eye. RESULTS: Testing sensitivity for the non-ophthalmologist examiners using direct and indirect ophthalmoscopy was 96% and 92%, respectively. Combining the results from direct and indirect ophthalmoscopy, the Clopper-Pearson 95% sensitivity confidence interval for identifying abnormal arterioles and venules was 82% to 99%, with a point estimate of 95%. CONCLUSION: These data suggest that non-ophthalmologist examiners can detect posterior pole vascular abnormalities in premature infants. If properly trained, they could possibly play a role in screening or follow-up examinations for ROP.

Interstitial deletion of 8q21-->22 associated with minor anomalies, congenital heart defect, and Dandy-Walker variant.

We describe an infant with a deletion of 8q21-->22 who had distinct clinical manifestations including minor facial anomalies, a congenital heart defect, a Dandy-Walker variant, and mild to moderate developmental delay. Her facial characteristics included small, wide-spaced eyes, asymmetric bilateral epicanthal folds, a broad nasal bridge, a "carp-shaped" mouth, micrognathia, and prominent, apparently low-set ears. Three other reports describe children with larger proximal deletions of 8q that include 8q21 and q22. These four children all have similar facial appearance. Of the others reported, one had a congenital heart defect and one had craniosynostosis. This case, in addition to the previously noted three cases, helps in delineating a recognizable syndrome.

In utero adrenal hemorrhage associated with fetal distress, subsequent transient neonatal hypertension, and a nonfunctioning ipsilateral kidney.

We present an unusual case of in utero adrenal hemorrhage associated with fetal distress. This case was further complicated by transient neonatal hypertension that resolved spontaneously and a nonfunctioning ipsilateral kidney. We discuss the possible underlying pathophysiology.

Early phonological and lexical development and otitis media: a diary study.

This diary study describes early phonological and lexical development in a child with chronic otitis media with effusion. Equipped with the tools of a referential/analytic language-learner, the child solved the problem of reduced and fluctuating auditory input with phonological selection and avoidance strategies that capitalized on prosodic cues. This 'tone-language' approach resulted in a lexical inventory that would be categorized as an extreme expressive style. Having 'boot-strapped' her lexical learning, the child continued to rely on phonological constraints and selection strategies to fuel lexical and syntactic growth, i.e. cross-domain interactions leading to a vocabulary spurt and the onset of two-word utterances. These findings illustrate the need to consider interactions among performance, input and linguistic constraints in order to explain individual variation in language learning.