Eye pathologies in neonates

Clinical usefulness of the baby vision test in young children and its correlation with the Snellen chart

AIM

To investigate the efficacy of a new visual acuity (VA) screening method, the baby vision test for young children.

METHODS

A total 105 eyes of 65 children aged 2-8y were included in the study. Acuity testing was conducted using a standardized recognition acuity chart (Snellen visual chart: at 3 m) and the baby vision model assessment. The baby vision device includes a screen, a near infrared camera and a computer. Children were seated at a measured distance of 33-40 cm from a display for testing. VA was estimated according to the highest resolution the children could follow. Decimal VA data were converted to logarithm of the minimum angle of resolution (logMAR) for statistical analysis. The VA results for each child were recorded and analyzed for consistency.

RESULTS

The mean VA measured using the Snellen visual chart was 0.62±0.32, and that assessed using the baby vision test was 0.66±0.27. The 95% limit of agreement was -0.609 to 0.695, with 95.2% (100/105) plots within the 95% limits of agreement. VA values of the baby vision test were significantly correlated with those of the Snellen chart (R=0.274, P=0.005).

CONCLUSION

The baby vision test can be used as a relatively reliable method for estimating VA in young children. This new acuity assessment might be a valid predictor of optotype-measured acuity later in preverbal children.

Analgesia for retinopathy of prematurity screening: A systematic review

BACKGROUND AND AIMS

Premature neonates require regular ophthalmological examination, generally indirect ophthalmoscopy, to screen for retinopathy of prematurity (ROP). Conventional analgesia is provided with topical anesthetic eyedrops and oral sugar solution, but neonates still experience significant pain. Here, the literature base was examined to evaluate the usefulness of other pharmacological analgesics.

MATERIALS AND METHODS

A systematic review was undertaken, adhering to a PROSPERO preregistered protocol in accordance with PRISMA guidelines (identifier CRD42022302459). Electronic databases were searched for primary research articles on pharmacological pain interventions used for ROP screening in neonates. The primary outcome measure was pain scores recorded using validated pain scoring tools, with and without pharmacological interventions in neonates during eye examination. For analysis, studies were separated into two categories: topical anesthesia and alternative pharmacological treatments.

RESULTS

Eleven studies met the inclusion criteria. Topical analgesia, oral paracetamol, and intranasal fentanyl were found to be effective in reducing the pain of eye examination. Oral morphine and inhaled nitrous oxide had no significant effect on premature infant pain profile (PIPP) scores during indirect ophthalmoscopy.

DISCUSSION

In addition to topical anesthesia, premedication with oral paracetamol is recommended during screening examination for ROP. The routine use of fentanyl is not recommended due to the risk of potential side effects. Non-pharmacological measures, such as sweet oral solutions and comfort techniques should also be employed. Further research is required to determine whether the use of nitrous oxide has a role, and to develop a safe and effective analgesic strategy to fully ameliorate the pain of ROP screening.

Advances in biomaterials for the treatment of retinoblastoma

Retinoblastoma is the most common primary intraocular malignancy in children. Although traditional chemotherapy has shown some success in retinoblastoma management, there are several shortcomings to this approach, including inadequate pharmacokinetic parameters, multidrug resistance, low therapeutic efficiency, nonspecific targeting, and the need for adjuvant therapy, among others. The revolutionary developments in biomaterials for drug delivery have enabled breakthroughs in cancer management. Today, biomaterials are playing a crucial role in developing more efficacious retinoblastoma treatments. The key goal in the evolution of drug delivery biomaterials for retinoblastoma therapy is to resolve delivery-associated obstacles and lower nonlocal exposure while ameliorating certain adverse effects. In this review, we will first delve into the historical perspective of retinoblastoma with a focus on the classical treatments currently used in clinics to enhance patients' quality of life and survival rate. As we move along, we will discuss biomaterials for drug delivery applications. Various aspects of biomaterials for drug delivery will be dissected, including their features and recent advances. In accordance with the current advances in biomaterials, we will deliver a synopsis on the novel chemotherapeutic drug delivery strategies and evaluate these approaches to gain new insights into retinoblastoma treatment.

Congenital Tarsal Kink Syndrome: Literature Review and Case Report

Background: The congenital tarsal kink syndrome is a rare form of congenital upper eyelid entropion associated with cardiovascular, musculoskeletal or central nervous system disorders. This syndrome must be recognized and surgically treated as a perinatal emergency to avoid associated complications—corneal ulcer, corneal leucoma, secondary amblyopia and decreased vision among children. Methods: A literature review was conducted to clarify the diagnosis particularities and the corrective surgery options of the congenital entropion on the upper eyelid. Results: Four relevant studies were found by researching the Web of Science and PubMed databases up to November 2021 for “congenital tarsal kink syndrome” and “congenital upper eyelid entropion”. Conclusions: In this paper, we present a case of congenital unilateral entropion of the upper left eyelid in the context of a tarsal kink syndrome in a one-month old infant, manifested by the absence of eyelashes on the upper eyelid of the left eye, hyperlacrimation and conjunctival hyperemia. Essential in managing the upper eyelid entropion is protecting the cornea. Furthermore, correcting a tarsal kink is eminently surgical, choosing between open or closed procedures. Herein, we address the difficulty in the timely diagnosis of this uncommon condition and make formal recommendations based on all reported cases.

Evaluation of the red reflex: An overview for the pediatrician

BACKGROUND

Red reflex test (RRT) is a simple, non-invasive method that can be performed easily by pediatricians during the clinical examination in neonatal period, infancy and childhood. Abnormal reflexes can lead to prompt diagnosis of several ocular disorders, with potentially severe consequences on patient's vision, cognitive function and even life.

AIM

To underline the contribution of pediatricians to early detection of vision and life threatening diseases by using RRT effectively.

METHODS

For the present systematic review, PubMed searches were performed using the key words "red reflex and newborn"; "red reflex and neonate"; "red reflex and complications"; "red reflex and necessity"; "red reflex and retinoblastoma"; "red reflex and congenital cataract"; "red reflex and glaucoma"; "red reflex and prematurity"; "red reflex and leukocoria"; "red reflex and blindness"; "red reflex sensitivity and specificity"; "red reflex and differential diagnosis"; "red reflex and guidelines". The relevant articles were selected without language restrictions. When a full-text publication was not available, their English abstracts were used. In some cases, studies from the reference lists of the selected articles provided useful information. The research took place in September 2020, in the Ophthalmology Department of University Hospital of Alexandroupolis.

RESULTS

A total of 45 articles were selected according to the used key words. After reviewing data from these articles, it is supported that red reflex remains an effective tool of undeniable importance for early detection of severe eye conditions, such as cataract, retinoblastoma, retinopathy of prematurity and glaucoma. Although literature reports some limitations of RRT, including a notable percentage of false positive tests, the inability to detect small, peripheral retinoblastomas and the lower sensitivity for posterior segment pathology, it is widely accepted that the benefits from the regular evaluation of the test on public health are significant. Therefore, RRT has been established by international guidelines and should be an essential component of pediatricians clinical practice. Red reflex implementation should be incorporated in pediatricians educational programs, so that they would be able to provide quality services and safe diagnoses.

CONCLUSION

The implementation of RRT should be encouraged in all neonatal/pediatric departments. Prompt education of pediatricians should be empowered in order to achieve careful vision screening, according to current guidelines.

Neonatal eye screening for 203 healthy term new-borns using a wide-field digital retinal imaging system

Background

The current practice for new-born eye examination by an Ophthalmologist in Malaysian hospitals is limited to only preterm new-borns, syndromic or ill infants. Healthy term new-borns are usually discharged without a thorough eye examination. This study is aimed at determining the proportion and types of ocular abnormalities detected in purportedly healthy term new-borns.

Method

This cross-sectional study is comprised of 203 participants, all purportedly healthy term new-born infants from the Obstetrics and Gynaecology ward at Hospital Kuala Lumpur over a 6 months period. The examination list includes external eye examination, red reflex test, and fundus imaging using a wide-field digital retinal imaging system (Phoenix Clinical ICON Paediatric Retinal Camera) by a trained Investigator. The pathologies detected were documented. The results were compared and correlated with similar studies published in the literature previously.

Results

Total ocular abnormalities were detected in 34% of the infants. The most common finding was retinal haemorrhage in 29.6% of the infants, of which 53.3% occurred bilaterally. Spontaneous vaginal delivery (SVD) remained the greatest risk factor which has nearly 3.5 times higher risk of new-borns developing retinal haemorrhage compared to Lower Segment Caesarean Section (LSCS). There was a 6% increased likelihood of developing retinal haemorrhage for every 1-min increment in the duration of 2nd stage of labour.

Conclusion

Universal eye screening for all new-borns using a wide-field digital imaging system is realistically possible, safe, and useful in detecting posterior segment disorders. The most common abnormality detected is retinal haemorrhage.

Vision Screening in Infants Attending Immunization Clinics in a Developing Country

Background: Vision screening in infants is an important part of the medical care of children as some eye abnormalities, if not treated in the first few months or years of life, can lead to irreversible vision loss. Objective: The objective of this cross-sectional, descriptive study was to identify ocular anomalies among infants attending immunization clinics in Nigeria and refer promptly and appropriately. Methodology: Infants were screened across 6 immunization clinics. Screening activities included relevant ocular history, vision assessment, external ocular examination, ocular motility, Hirschberg's test, pupil examination, and the red reflex test. Infants with abnormal findings were referred for comprehensive eye examination. Result: Of the 142 infants who underwent vision screening, 29 were referred. These referrals were either as a result of ocular abnormalities (n = 22) or presence of risk factors from history (n = 7). The prevalence of ocular abnormalities was 15.5% and neonatal conjunctivitis (38%), was the commonest ocular abnormality found. Others were bacterial conjunctivitis (14%), nasolacrimal duct obstruction (14%), strabismus (14%), capillary hemangiomas (10%), iris nevi (5%), and vernal keratoconjunctivitis (5%). Of the 7 infants referred based on history alone, 6 (85.7%) had a history of prematurity. Conclusion: Conjunctivitis, strabismus, congenital nasolacrimal duct obstruction, and capillary hemangioma are some of the prevalent disorders seen in infants at immunization clinics in Nigeria. Babies at risk of retinopathy of prematurity (preterm birth and oxygen therapy) can be identified. Immunization clinics can serve as good points of vision screening for infants in developing countries to facilitate prompt referral and treatment.

Didelphis albiventris: an overview of unprecedented transcriptome sequencing of the white-eared opossum

BACKGROUND

The white-eared opossum (Didelphis albiventris) is widely distributed throughout Brazil and South America. It has been used as an animal model for studying different scientific questions ranging from the restoration of degraded green areas to medical aspects of Chagas disease, leishmaniasis and resistance against snake venom. As a marsupial, D. albiventris can also contribute to the understanding of the molecular mechanisms that govern the different stages of organogenesis. Opossum joeys are born after only 13 days, and the final stages of organogenesis occur when the neonates are inside the pouch, depending on lactation. As neither the genome of this opossum species nor its transcriptome has been completely sequenced, the use of D. albiventris as an animal model is limited. In this work, we sequenced the D. albiventris transcriptome by RNA-seq to obtain the first catalogue of differentially expressed (DE) genes and gene ontology (GO) annotations during the neonatal stages of marsupial development.

RESULTS

The D. albiventris transcriptome was obtained from whole neonates harvested at birth (P0), at 5 days of age (P5) and at 10 days of age (P10). The de novo assembly of these transcripts generated 85,338 transcripts. Approximately 30% of these transcripts could be mapped against the amino acid sequences of M. domestica, the evolutionarily closest relative of D. albiventris to be sequenced thus far. Among the expressed transcripts, 2077 were found to be DE between P0 and P5, 13,780 between P0 and P10, and 1453 between P5 and P10. The enriched GO terms were mainly related to the immune system, blood tissue development and differentiation, vision, hearing, digestion, the CNS and limb development.

CONCLUSIONS

The elucidation of opossum transcriptomes provides an out-group for better understanding the distinct characteristics associated with the evolution of mammalian species. This study provides the first transcriptome sequences and catalogue of genes for a marsupial species at different neonatal stages, allowing the study of the mechanisms involved in organogenesis.

Genetic Testing in Pediatric Ophthalmology

The authors review the utility of genetic testing in ophthalmic disorders - precise diagnosis, accurate prognosis, genetic counseling, prenatal diagnosis, and entry into gene-specific therapeutic trials. The prerequisites for a successful outcome of a genetic test are an accurate clinical diagnosis, a careful family history that guides which genes to study, and genetic counseling (both pre-test and post-test). The common eye disorders for which genetic testing is commonly requested are briefly discussed - anophthalmia, microphthalmia, coloboma, anterior segment dysgenesis, corneal dystrophies, cataracts, optic atrophy, congenital glaucoma, congenital amaurosis, retinitis pigmentosa, color blindness, juvenile retinoshisis, retinoblastoma etc. A protocol for genetic testing is presented. If specific mutations in a gene are common, they should form the first tier test, as the mutations in Leber hereditary optic neuropathy. If mutations in one gene are likely, sequencing of that gene should be carried out, e.g. GALT gene in galactosemia, RS1 gene in retinoshisis. Disorders with genetic heterogeneity require multi-gene panel tests, and if these show no abnormality, then deletion / duplication or microarray studies are recommended, followed in sequence by clinical exome (5000 to 6000 genes), full exome (about 20,000 genes or whole genome studies (includes all introns). It is fortunate that most genetic tests in ophthalmology are available in India, including gene panel and whole exome/genome sequencing tests.