Eyes Adapted from Mosby’s Guide to Physical Examination, 6th Ed. Ch. 11 Development • By 2-3 months… – Voluntary control of eye muscles – Lacrimal ducts carry tears into nasal meatus • By 8 months… – Can differentiate colors • By 9 months… – Eye muscles coordinate; a single image is percieved Visual Development • Be familiar with Table 11-1(Mosby) Chronology of Visual Development Infant Eye Exam - Tips • Often shut their eyes tightly – Difficult to separate the eyelids To encourage the infant to open their eyes… – Use a dimly lit room – Hold the infant upright, suspended under its arms – Have parent hold infant over a shoulder Infant Eye Exam - Tips Even when the infant is crying, you may get a glimpse at the eyes. • Note anything you see… – – – – Symmetry Extraocular muscle balance Red reflex Etc. Infant Exam Inspect External Eye • Size of eyes – Small or different sized eyes • Eyelids – Epicanthal folds • Asian populations • Down syndrome – Position – Swelling • Slant of palpebral fissures Inspect the level of the eyelid covering the eye… To detect the “Setting Sun Sign”… – Rapidly lower the infant from upright to supine position – Look for sclera above the iris Differentials include: – Expected variant in newborn – Hydrocephalus – Brainstem lesion Note distance between the eyes… • Hypertelorism (widely spaced eyes) – may be associated with mental retardation Strabismus? Exoptropic vs. Esotropic Tests include: • Corneal light reflex (Hirschberg’s Test) • Cross-Cover Test • Cover-Uncover Test Corneal Light Reflex (Hirschberg’s Test) • Child stares at a penlight about 30 cm away • Doctor looks at the reflection from each cornea – In relationship to the pupil Normal: symmetrical Strabismus: asymmetrical Cross-Cover Test • Patient stares at penlight • Doctor covers one eye and observes the uncovered eye for movement Normal: no movement Exotropia: moves lateral to medial Esotropia: moves medial to lateral Cover-Uncover Test • Patient stares at the penlight • Doctor covers one eye and then observes as it is uncovered Normal: no movement (remains fixed on the light) Exotropia: eye moves lateral Esotropia: eye moves medial Inspect • Sclera • Conjunctiva • Pupil – Coloboma? • Iris – Brushfield spots? CLINICAL NOTE • A newborn’s eyelids may be swollen or edematous, accompanied by conjunctival inflammation and drainage – Consequence of routinely administered antibiotics Beyond the newborn period… • Redness • Hemorrhage • Discharge • Granular appearance …may indicate infection, allergy, or trauma. Cranial Nerves II, III, IV, VI “Vision is grossly examined by observing the the infant’s preference for looking at certain objects.” Cranial Nerves II, III, IV, VI 1. Expect the infant to focus and track through 60 degrees 2. Optical blink reflex – – Shine a bright light at the infant’s eyes Note the quick closure of the eyes and dorsiflexion of the head 3. Corneal light reflex (Hirschberg’s) Fundoscopic Examination • Deferred until 2-6 months – Very difficult to conduct on a newborn or young infant – Unless there is a need • premature infant – visual problems Red Reflex *Should be elicited in every newborn • Observe for opacities, dark spots, or white spots within the circle of red glow Congenital cataracts Retinoblastoma Exam Recommendations for Primary Care Physicians Newborn – 3 months Screening Method Require Further Evaluation Red reflex Abnormal Asymmetric Corneal light reflex Asymmetric Inspection Structural abnormality 6 months – 1 year Screening Method Require Further Evaluation Red reflex Abnormal or Asymmetric Corneal light reflex Asymmetric Differential occlusion Failure to object equally to covering each eye Fix and follow with each eye Failure to fix and follow Inspection Structural abnormality ~3 years old Screening Method Require Further Evaluation Visual acuity <20/50; 2 lines of difference between the eyes Red reflex Abnormal or asymmetric Corneal light reflex; Asymmetric; ocular Cover-uncover refixation movements Failure to appreciate Stereoacuity random dot stereogram Inspection Structural abnormality ~5 years old Screening Method Require Further Evaluation Visual acuity 20/30 or worse Red reflex Abnormal or asymmetric Corneal light reflex; Asymmetric; ocular Cover-uncover refixation movements Failure to appreciate Stereoacuity random dot stereogram Inspection Structural abnormality Child Exam Children • Inspect the external eye structure (same as infant) – – – – – Size of eyes Eyelids Palpebral fissures Distance between eyes Strabismus Inspect • • • • Sclera Conjunctiva Pupil Iris Beyond the newborn period… • Redness • Hemorrhage • Discharge • Granular appearance …may indicate infection, allergy, or trauma. Visual Acuity – Younger Children • Observe play with toys – Stacking, building, or placing objects inside of others If tasks are performed well, vision difficulties are unlikely. Visual Acuity *Usually ~3 years of age • Tested when child can cooperate with the Snellen* E game – Ask which way the “legs” are pointing *Also available with different shapes Snellen E Chart – Tips • Allow the child to practice following instructions before you administer the test – Instruct the child to point finger in the direction of the legs of the E • Have parent assist with covering one eye Snellen E Chart REMEMBER: *Test each eye seperately *With and without corrective lenses 20/25 +2 • Means that they can read all on the 20/25 line and 2 from the 20/20 line. Anticipated Visual Activity Age Visual Acuity 3 years 20/50 4 years 20/40 5 years 20/30 6 years 20/20 “When testing visual acuity in the child, any difference in the scores between the eyes should be detected.” • A 2 line difference (20/50 and 20/30) may indicate amblyopia – Reduced vision in an eye that appears structurally normal – In strabismus, the eye may be “unused” Extraocular Movements • Six cardinal fields of gaze • Peripheral vision – Parent may hold the child’s head still – Use a teddy bear or toy – Have child sit on parent’s lap Fundoscopic Exam – Child • PATIENCE! – often unable to keep eyes still and focused on a distant object • May want to do the exam with the patient supine… Fundoscopic Exam – Supine • Child laying supine on the exam table with head near the end • Stand at the end of the table • Use Rt. eye to examine the child’s Lt. NOTE: – Retinal findings will appear upside down – Inspect the optic disc, fovea, and vessels as they pass by Fundoscopic Exam – Tips • Do not hold the child’s eyelid open forcibly – Leads only to resistance • Often results are better when the child sits on the parent’s lap Common Conditions Strabismus Eyes do not focus on an object simultaneously… concern of amblyopia developing Paralytic • Impairment of extraocular muscles or their nerve supply Nonparalytic • No primary muscle weakness • Can focus with either eye but not both simultaneously Pseudostrabismus • Symmetrical corneal light reflex • Common in Asian and Native American populations • Disappears by 1 yoa Strabismus (esotropic) • Asymmetrical light reflex Coloboma “Keyhole pupil” • Loss of functional pupil • Often associated with other congenital abnormalities Brushfield spots • White specks in a linear pattern around the circumference of the iris – Strongly suggests Down syndrome Congenital Cataracts • Requires a full metabolic, infectious, systemic, and genetic workup… Common causes: – Infectious diseases – – – – • TOxoplasmosis, Rubella (MC), Cytomegalovirus, & Herpes Hypoglycemia Trisomies Prematurity Etc. Retinoblastoma • Congenital malignant tumor (retina) • <2 years old Initial sign: “white” reflex (aka cat’s eye reflex) Fundoscopic exam – Ill-defined mass arising from the retina – Chalky-white areas of calcification Horner Syndrome • Interruption of sympathetic nerve supply to the eye – Clinical presentation: • Ipsilateral miosis (constriction)& mild ptosis – Causes: • Operative trauma • Mediastinal tumors • Metastatic tumors • Bronchogenic carcinoma Congenital Horner Syndrome • Damage to the lower brachial plexus (birth trauma) • Sometimes seen with Klumpke’s Palsy Retinopathy of Prematurity • Blood vessels are straightened and diverted temporally • Cicatricial changes may be severe – Retinal detachment – Glaucoma – Blindness Retinal HemorrhagesShaken Baby Syndrome • Multiple hemorrhages Whenever retinal hemorrhages are seen, you must suspect infant abuse