Imran Karim Janmohamed
Foundation Year 1 Doctor, East Surrey Hospital, Redhill, Surrey
Introduction
Eyesight is often regarded as the most valuable human sense (1). Thus, the identification and prevention of ophthalmic pathologies in neonates is a key component of the newborn examination in order to commence the management of ophthalmic conditions before they persist and lead to irreversible damage. In the UK, the standard Newborn Infant Physical Examination (NIPE) comprises an assessment of the eye in order to identify features such as abnormal eye movements, decreased visual acuity and symmetry of gaze that may point to early pathologies. As practitioners, it is important to identify signs that warrant further specialist examination, with appropriate follow-up, or features that can actually be normal in infants and children to reassure parents and caregivers. This article aims to provide an overview of this examination.
Preparation and initial interaction
Examining a child can be challenging due to difficulties in ensuring adequate engagement and comfort. Widen the ‘window of opportunity’ by advising that the child have a feed, recent sleep and a short wait before the consultation (2). Elicit any concerns that the child’s guardian may have by taking a brief history, which should also include a family history of ophthalmic problems. Be calm, friendly and gentle when examining the baby. It is probably a good idea to rest the baby on the parent or caregiver’s lap, with a toy or pacifier at hand if they are more restless.
Examination
Visual Acuity and attention
Watch the child as it is carried into the room and note when eye contact is made with you while smiling and at what distance. Consider doing the same with the child looking at itself in the mirror and identify the maximum distance at which they maintain their interest in their face (2). These help to estimate visual acuity.
Demonstrate the red reflex
This is performed using a direct ophthalmoscope in dim lighting, whilst standing at least 18 inches away, with the light projecting onto both eyes simultaneously. A normal finding should elicit the reflex in both eyes symmetrically. An abnormal reflex will be white (“leukocoria”) or a diminished reflex in one or both eyes, for example due to congenital cataract or retinoblastoma2,3. These are extremely important to elicit; vision and seeing are learnt in the initial years of life, and conditions which can be treated, such as cataracts, but left unresolved, can cause total loss of vision if left to persist, even when treated years later. Table 1 details common causes for leukocoria in the neonate.
An abnormal red reflex should prompt immediate specialist referral to an ophthalmologist. Referral should also seriously be considered in all newborns with a family history of retinoblastoma, cataracts, glaucoma, or retinal abnormalities.
| Cause | Description |
|---|---|
| Congenital cataract | A cataract is an opacity of the lens that typically occurs in older individuals. Congenital causes are uncommon and include genetic or systemic disorders. These may, for example, be associated with TORCH infections (toxoplasmosis, other agents, rubella, cytomegalovirus (CMV), herpes simplex). |
| Retinoblastoma | An embryonal tumour of the retina and the commonest intraocular malignancy in children. It can be either heritable or non-heritable. 40% of cases are heritable and caused by a mutation in the Retinoblastoma 1 gene on chromosome 13 (4). |
| Chorioretinitis | Inflammation of the retina and choroid. In neonates, the commonest congenital causes are CMV and toxoplasmosis. Both are often asymptomatic at birth. CMV-related chorioretinitis often remains stable and improves in infancy. Chorioretinitis associated with toxoplasmosis may progress years after birth, present bilaterally, and go on to threaten vision (5). |
| Coats disease | Congenital disorder caused by abnormal blood vessels (aneurysms and telangiectatic vessels) behind the retina, which lead to progressive deterioration of vision. It more frequently occurs in males (ratio of 3:1) and 95% present unilaterally (6). |
| Coloboma | Full-thickness developmental abnormality of the eye that arises during the embryonic stage, involving one or more structure of the eye, e.g. the eyelid, cornea, and optic disc among others (7). |
| Persistent foetal vasculature | Failure of the involution of a component of the foetal ocular vasculature (the tunica vasculosa and hyaloid systems). It is the second commonest cause of infantile leukocoria (8). |
| Retinopathy of prematurity | Abnormal blood vessel development, which occurs in premature infants. Particularly affects babies born before 32 weeks’ gestation, or who weigh less than 1,500 grams at birth. These babies will receive regular (1-2-weekly) screening tests by an ophthalmologist (9). |
| Vitreous haemorrhage | Blood clot in the vitreous body, often due to trauma or haemorrhagic disease. |
Penlight exam of eyelids, pupils and external eye structures
Assess and compare for eye colour, pupil size, drooping eyelids, teary eyes, photosensitivity, conjunctival injection, eye movement and spacing between the eyes. Note for the presence of swollen lacrimal sac, blepharitis, and slow or limited pupil constriction (2,3,10). Misalignment of the eyes (amblyopia or strabismus) can be easily assessed by shining a light in the eyes and observing the symmetry of the reflection in the pupils – the ‘corneal light reflex’. Pseudostrabismus, which is characterised by a wide nasal bridge or epicanthal folds, can misleadingly give the impression of eye deviation; however, the corneal light reflect will be symmetric.
Table 2 outlines findings on eye examination associated with congenital defects.
| Feature | Description |
|---|---|
| Coloboma | Several syndromes involve coloboma together with multisystem malformations, such as CHARGE syndrome (Coloboma, Heart anomalies, Choanal atresia, Restriction of growth and/or development, Genital and Ear abnormalities), or Treacher Collins syndrome. |
| Inner Epicanthal folds | Vertical folds of skin at the medial canthi. May give the impression of esotropia in the newborn. Normal variant in Asian and native American patients. Associated with congenital syndromes, e.g. Down Syndrome and Noonan Syndrome. Reflection of the pen torch in the pupil, and comparison between both eyes, can help rule this out (11). |
| Orbital separation | Hypertelorism Widely spaced eyes. Associated with Trisomy 18 (Edward’s syndrome). Contrast with telecanthus, which is the wide separation of the medial canthi; the orbits are normally positioned. Hypotelorism Narrowly spaced eyes. Associated with Foetal Alcohol Syndrome. |
| Orbital orientation | Downslanting palpebral fissures Eyes form a “^” shape, e.g. in Marfan’s Syndrome. Upslanting palpebral fissures Eyes form a “V” shape, e.g. in Down Syndrome. |
Visual attention, visual fields and eye movements
To test the newborn’s eye movements, quickly introduce a toy or brightly-coloured object into one quadrant of vision, then move the toy away as you introduce another one in another quadrant and attention switches. Observe for fast eye movements towards the object. Lack of eye movement may indicate a hemianopic visual field or hemi-attentional deficit. Keep an eye out for nystagmus and whether both eyes do not respond at the same time (2).
Normal findings that may cause worry
A number of ophthalmic symptoms and signs are benign but may cause worry in an infant or child’s parents. Table 3 below summarises a number of these normal findings (11).
| Feature | Description |
|---|---|
| Following delivery | Subconjunctival haemorrhage Results from rupture of blood vessels. May take weeks to resolve. Lid oedema and lid eversion |
| Dysconjugate gaze | This is a result of the low visual acuity of newborns, which is approximately 20/400. Normal in the first 2-3 months of a newborn’s life, but should prompt referral if persistent. |
| Nasolacrimal duct obstruction | The blocked tear duct (mainly at the valve of Hasner) results in epiphora (overflow of tears), and sticky yellow secretions from the eye. 90% of cases resolve within 1 year and first line management commonly involves observation and massaging of the lacrimal sac with a warm, moist cloth for the first 12 months of life. It is important to distinguish nasolacrimal duct obstruction from ophthalmia neonatorum, which is conjunctivitis within the first 4 weeks of life, most commonly caused by chlamydial infection. |
References
1. Enoch J, McDonald L, Jones L, Jones PR, Crabb DP. Evaluating Whether Sight Is the Most Valued Sense. JAMA Ophthalmol. 2019;137(11):1317-1320. doi:10.1001/JAMAOPHTHALMOL.2019.3537
2. Blaikie AJ, Dutton GN. How to assess eyes and vision in infants and preschool children. BMJ. 2015;350. doi:10.1136/BMJ.H1716
3. Lewis ML. A Comprehensive Newborn Exam: Part I. General, Head and Neck, Cardiopulmonary – American Family Physician. https://www.aafp.org/afp/2014/0901/p289.html#sec-3. Accessed March 13, 2022.
4. Lohmann DR, Gallie BL. Retinoblastoma. GeneReviews®. November 2018. https://www.ncbi.nlm.nih.gov/books/NBK1452/.
5. Lowth M, Tidy C. Chorioretinal Inflammation, Eye Disease. Patient | Patient. https://patient.info/doctor/chorioretinal-inflammation#ref-15.
6. Tsakiris KA, Epley D, Shah VA, et al. Coats Disease – EyeWiki. American Academy of Ophthalmology. https://eyewiki.aao.org/Coats_Disease#cite_ref-1. Published 2013.
7. Onwochei BC, Simon JW, Bateman JB, Couture KC, Mir E. Ocular colobomata. Surv Ophthalmol. 2000;45(3):175-194. doi:10.1016/S0039-6257(00)00151-X
8. Ramasubramanian A, Madison Duff-Lynes S, Tripathy K, Deshmukh S, Prabhu S, Hartnett ME. Persistent Hyperplastic Primary Vitreous – EyeWiki. American Academy of Ophthalmology Academy of Ophthalmology. https://eyewiki.aao.org/Persistent_Hyperplastic_Primary_Vitreous#cite_note-hartnett10-9. Published 2017.
9. Hellström A, Smith LEH, Dammann O. Retinopathy of prematurity. Lancet. 2013;382(9902):1445. doi:10.1016/S0140-6736(13)60178-6
10. Moses S. Eye Examination in Children. https://fpnotebook.com/Eye/Exam/EyExmntnInChldrn.htm#fpnContent-panel-id_4.
11. BELL AL, RODES ME, KELLAR LC. Childhood Eye Examination – American Family Physician. American Family Physician. https://www.aafp.org/afp/2013/0815/p241.html. Published 2013.