Ophtha Pediatric Ophthalmology 2

Pediatric Ophthalmology Catherine Qui-Macaraig, MD 10 warning signs of treatable eye disease in the newborn Needs early definitive treatment •1. Leukocoria •2. Drooping Eyelid •3. Enlarged Cornea of one or both eyes 10 warning signs of treatable eye disease in the newborn and infant. Serious but infrequent •Cataract - 1 in 250,000 •Glaucoma - 1 in 10,000 •Retinoblastoma - 1 in 20,000 10 warning signs of treatable eye disease in the newborn and infant. •Should be evaluated soon •#4 Tearing, Discharge, Redness •#5 Strabismus •#6 Nystagmus •#7 Prematurity - Low Birth Weight - requires monitoring of the retina for development 10 warning signs of treatable eye disease in the newborn and infant Should be evaluated at next routine visit •#8 Abnormal Head Posture •#9 Pupil Defect •#10 Anisocoria The Bruckner Test •View two eyes simultaneously through a direct ophthalmoscope •Infant is upright and in a darkened room •Detects medial opacities, refractive errors, strabismus, large posterior fundus lesions

1. White Pupil (Leukocoria) Congenital Cataract •1) Diagnosis must be early to avoid - amblyopia - nystagmus if bilateral •2) Surgical treatment should be early •3) Requires special surgical technique - different from adults.

•4) Optical rehabilitation is difficult with contact lenses or glasses. •5) Any delay in treatment or lapse in optical or amblyopia treatment results in amblyopia. •6) Even in the best of circumstances vision after congenital cataract treatment is never normal. Congenital Cataracts Bilateral Retinoblastoma 2. Drooping Lid Lump or swelling of lids •- this can be a sign of cellulitis, tumor, hemangioma, etc. - amblyopia – from pupillary occlusion Capillary Hemangioma Marcus Gunn Jaw-Winking Phenomenon Drooping of the lid (or lids) •chin-up head back posture which retards motor development. 3 Enlarged Cornea of One or Both Eyes Congenital glaucoma •with tearing and photophobia.

• requires early and specialized surgical treatment including goniotomy, trabeculotomy, and filtering Congenital Glaucoma

•EARLY: -

Epiphora - Increase IOP - Glaucomatous optic disc cupping. Photophobia, loss of corneal luster

LATE: •- corneal diameter greater than 10.5 mm •- increased anterior chamber depth •- corneal opacity Congenital Glaucoma •7 year old with microcephaly •Cong. GL OU •Goniotomy at 12 days •Repeat surgery 2 weeks later on OS•Trabeculectomy-trabeculotomy

4 Excessive Tearing or Discharge This can be a sign of •glaucoma •infection •light sensitivity – from corneal problems, uveitis, etc. all of which require attention. 4 Excessive Tearing or Discharge •The most common cause is a blocked tear drainage system. •treated initially with gentle pressure over the tear sac and antibiotic drops. Symptoms •Manifest by age 1 month •Epiphora •Sticky mucoid or mucopurulent discharge •Bilateral involvement is common NLD Obstruction •gentle probing done before age 1 year. •Persistent tearing usually requires probing with general anesthesia often with placement of a silicone tube 5 Crossed Eyes

Eyes that deviate constantly should be evaluated immediately! Ocular Alignment in Neonates •Orthotropia 22.7 % •Exotropia 61.1 •Intermittent Exotropia 13.0 •Esotropia 0.2 •Intermittent Esotropia 0.5 •ET to XT 2.5 •Majority are orthotropic by 6 months of age

Strabismus Evaluation Cardinal Gazes Cardinal Gazes

Hirschberg Test Krimsky Cover Test •Cover-uncover Test – shows a manifest deviation e.g. esotropia •Alternate Cover Test – shows latent deviations too e.g. exophoria •Orthophoria- no shift on cover testing Cover Testing esotropia Exotropia Epicanthus •Vertical folds of skin over the medial canthi Pseudostrabismus Pseudostrabismus Who has crossed eyes? 6 Nystagmus Dancing Eyes -usually indicates subnormal vision -also often present in cerebral visual impairment 7 Head Tilt, Turn,Chin up or Chin down •Usu. starting at the time of sitting up or walking Head tilting can be a sign of •strabismus •disease of the central nervous system •an abnormality of the neck muscles Head tilt regardless of cause should be evaluated by an ophthalmologist. 8 Defect or Missing Part of the Pupil iris coloboma may be accompanied by retinal colobomata 9 Inequality of the Pupil Size •Persistent inequality of the pupil size can be a sign of serious disease or it may be an innocent finding. •If persistent, inequality of pupil size should be evaluated by an ophthalmologist. 10 Prematurity AAP/ AAO Screening Recommendation •a birth weight less than or equal to 1500 g •GA less than or equal to 28 weeks. also

ROP in Infants w/ BW >1250g •ROP in 18% of 1118 preemies from 1250g to 1600g •Stage 1 disease 11% •Stage 2 disease 3% •Stage 3 disease 3% •Stage 4 disease <1% •Gestational ages up to 32 weeks Recommendation •Screen 32 weeks and below •Or < 1500g Visual Acuity in Children •Visual acuity assessment •Conditions which predispose to amblyopia Visual Acuity Testing Testing Methods: •Infants •Pre-verbal children •Verbal Children Visual Acuity Assessment in Infants Visual Acuity Assessment in Infants: Importance •permits early, efficient detection of preventable or treatable causes of visual loss •to monitor response to therapy •provides clues to development in other neurologic systems Normal Visual Development •OKN- birth

•Ocular alignment stabilized- 1 month •Fixation- 2 months •Response to visual threat- 2-5 months •Smooth pursuit- 6-8 weeks Normal Visual Development (cont’d) •Accommodation- 4 months •Stereopsis- 3-7 months •Foveal maturation- 4 months •Contrast sensitivity- 7 months •Optic nerve myelination- 7 months to 2 years Age-related Visual Acuity Estimates by Test Method Birth to 2 months •Acuity at 20/400 to 20/60 Methods: •Observation response to light- blinks, flinches fixes and follows objects •OKN Drum Clinical Assessment in the Nursery •neonates fix and follow gross fixation targets •human face is most attractive •absence of fixation may mean lack of attention •babies follow a full arc of 180 degrees only at 4 months 2 months to 6 months •Acuity 20/50 + Methods: •Observation: blink to threat reach for objects •OKN Drum The Bruckner Test •View two eyes simultaneously through a direct ophthalmoscope •Infant is upright and in a darkened room •Detects medial opacities, refractive errors, strabismus, large posterior fundus lesions

Clinical Assessment of Visual Function in Infants •Lid Popping Responses •Vestibulo-ocular Reflex •OKN Drum •Fixation Preference •Preferential Looking Techniques Lid Responses •Suddenly reduce room light •Upper lids should retract to expose 1 to 2 mm of sclera •In newborn to 6 month old infants •Absent in significant retinal or optic nerve abnormalities •May be present in milder forms of visual loss OKN Drum •An involuntary pursuit response •CF at 3 to 5 feet •Pursuit and saccadic systems can be investigated •Requires the child’s attention •More for evaluation of movement disorders Vestibulo-ocular Reflex (VOR) •Spin child to induce a vestibular nystagmus •Nystagmus should dampen in 30 to 60 seconds due to fixation •Continued beating implies low vision

Vestibulo-ocular responses Fixation Preference •Most commonly used •Known as the ‘csm’ method •With a manifest strabismus, cover fixing eye for deviating eye to take up fixation •With straight eyes, induce a tropia Fixation Method: CSM •Central: 20/20 to 20/200 •Steady: 20/200 or better Nystagmus •Wandering – poor prognosis •Pendular – often secondary to central visual loss •Jerk – more commonly of motor origin; with unexpectedly good vision in a compensatory head position Preferential Looking Techniques •Forced choice PLT assume the child will prefer to look at a patterned object •Teller Acuity Cards-for clinical use

Visual Acuity In Pre-verbal Children Visual Acuity Assessment in Preverbal Children •Sheridan-Gardner Test •HOTV •‘E’ Game •Landolt C •Lea Symbols HOTV •matching each test letter to one of the four letters held in the child's hands

H, O, T, and V printed on a card that can be

Illiterate E •indicate with fingers the direction of the legs of a letter E that is rotated to point up, down, left or right Snellen Equivalents Lea Symbols Lea Symbols •more similar in configuration to Snellen letters than the Allen pictures •carefully calibrated and assessed for reliability Testing Procedure •Position the child 20 feet from the chart •Cover one eye •Prompt her to read one line at a time •Read until majority of responses on a line are erroneuous •Acuity is recorded as the line above the last Points to Consider •Normal preschoolers often test no better than 20/30 or 20/40

•May do better on 2nd eye tested because of practice with 1st eye •May do worse on 2nd eye tested because of waning interest or fatigue

Factors which affect acuity testing •Short attention span •Kids like to peek and memorize •Lack of familiarity with the pictured objects What to do Short attention span •Have several brief sessions beginning with alternate eyes •Test only a few sample letters per line •Record observations relating to the child's general behavior during testing as well as the numeric result What to do Kids like to peek and memorize •Be constantly alert to peeking and guessing or memorization

•Hold the occluder yourself •Test eye in question first Lack of familiarity with the pictured objects •Testing should begin with a review of the cards up close

Verbal Children: Visual Acuity Testing Snellen Acuity •Numerator- testing distance in feet or •Denominator- distance from which a

meters normal eye can read the line

Basic Ophthalmologic Exam: Visual Acuity Testing Snellen Chart •Number - distance in feet or m from which a normal eye can read all the letters Basic Ophthalmologic Exam: Visual Acuity Testing •Example: 20

testing distance 60 distance at which N eye Subjective Acuity Assessment •Motoric responses required •Fixation preference persists in non-amblyopic patients •Bilateral loss may be missed •Requires highly skilled personnel Objective Tests •Motor response not required •Less dependence on examiner Visual Evoked Potentials •Flash-presence of LP -albinism testing •Pattern Reversal VEP • Sweep VECP Flash VECP Pattern Reversal VEP •Supra-granular layers in striate cortex •Highly reliable •prolonged in MS, optic neuritis •Macular disorders •Affected in amblyopia •Limitations: non-specific; time-consuming

Swept Spatial Frequency VECP •VA estimate based on Cortical Electrical Response •VEP amplitude measured to reversing gratings •Bar width changes from wide to thin •32 bar widths tested in 10 second period (sweep)

Sweep (cont’d) Pediatric applications:

can see same line

•Acuity measured newborn through senescence •Amblyopia •Organic visual loss •Motility restrictions precluding behavioral measures Sweep (cont’d) Limitations •Fixate for ten seconds •Electrode placements could be non-optimal •Optimal temporal rate changes with age Binocular VECPs •Gross stereopsis develops by 3-5 months •Correlates well with binocular fusion •Documents effects of early surgery in infantile esotropia

Amblyopia Definition •Amblyopia is an acquired defect in monocular vision caused by abnormal visual experience early in life. Amblyopia •Decreased visual acuity •Abnormal visual development •Unilateral or bilateral •Normal eye exam Amblyopia •The most common cause of visual impairment in children •Also, the leading cause of monocular visual loss in the 20 to 60+ age group, surpassing GL, diabetic retinopathy, macular degeneration and cataract Pathophysiology of amblyopia •No retinal changes - ERG OK •Lateral geniculate layers subserving amblyopic eyes atrophic •Cortical ocular dominance columns representing amblyopic eye less responsive to stimulus and show changes microscopically Clinical Behavior in Amblyopia

•Vision reduced - less than 20/40, or 2 lines difference

•Relatively better vision in reduced illumination (scotopic sight) compared to normal •Slow reading Vision reduced by crowding Predisposing Factors •Poor clarity – media opacities •Poor focus - refractive errors •Poor aim - strabismus Deprivation Amblyopia Unilateral Congenital Cataract •More severe amblyopia Bilateral Congenital Cataract Strabismic Amblyopia •Constant use of left eye causes suppression of right eye

amblyopia

•Alternation with alternate suppression avoids amblyopia. Anisometropic Amblyopia •difficult to detect because there are no obvious physical signs •usually only found at vision testing Ametropic Amblyopia Uncorrected high hyperopia is an example of this bilateral amblyopia. Importance of Early Detection

•Vision develops early •Treatment depends on plasticity of the visual system Sensitivity to development and treatment Visual maturity after this age, amblyopia is not likely to occur and in the usual case is not successfully treated. Amblyopia: Screening •Amblyopia is preventable •Early detection is key to effective treatment •Screening is the responsibility of the pediatrician or primary care physician Amblyopia Catherine Qui-Macaraig, MD Associate Professor UST Faculty of Medicine and Surgery Definition •Amblyopia is an acquired defect in monocular vision caused by abnormal visual experience early in life Amblyopia •Decreased visual acuity •Abnormal visual development •Unilateral or bilateral •Normal eye exam Amblyopia •The most common cause of visual impairment in children •Also, the leading cause of monocular visual loss in the 20 to 60+ age group, surpassing GL, diabetic reti nopathy, macular degeneration and cataract Development of the Nervous System: Forces acting on epithelia Driving forces: Birth of cells distant from where they function Migration Death of excess cells Modulating forces: Cell specialization-migrates to where they function Connectivity- synapses Synaptogenesis •The major activity going on in the brain at birth •Brings the brain from infant to adult form •The mechanism by which experience of the outer world molds and modifies the brain during the first few years of life Visual Development •Retinal ganglion cells ---LGN---layer 4C of occipital cortex •Visual experience produces a modular organization of columns in the cortex for orientation, binocular disparity, motion direction, color, etc. Visual Development •Receptive field- a neural unit which transduces light energy into nerve energy and sends it to the cortex –to be decoded by other receptive fields into the neural analog of the world as our eyes and brain see it •-brain starts off as being relatively insensitive but becomes sharper like pixels Visual Deprivation •Hubel and Wiesel sewed one eyelid of a kitten shut •atrophic LGN: cells of layers 2, 3, 5 of ipsilateral n. and cells of layers 1, 4, 6 of contralateral n. •Layer 4C of cortex: shrinkage of input from deprived eye and expansion of opposite columns •Change in LGN is attributed to loss of axons and terminals to support the cell bodies Critical Period of Visual Development •A period of rapid visual development •When the visual system is sensitive to abnormal input caused by stimulus deprivation, strabismus, or significant refractive errors •Mixed data: 1st 2 months 3 – 4 yrs. depending on input manipulation Amblyopia defined •“lazy eye” •A loss of visual acuity without an identified organic cause •Abnormal visual development 2ndary to abnormal visual stimulation •Practically, at least 2 snellen lines poorer than sound eye Functional vs. Organic Amblyopia •Organic - caused by structural abnormalities of the eye or brain, independent of sensory input

Characteristics of Amblyopia •Crowding phenomenon •Neutral density filter effect •Decreased contrast sensitivity •Eccentric fixation •Slow reading Crowding Phenomenon •Better VA with single optotypes than multiple optotypes •Contour interaction •One to two snellen lines better with isolated letters •Clinically shows possibility of improvement in visual acuity with adequate therapy •Neurons have large receptive fields; inc. spatial summation and lateral inhibition Neutral density filter effect •Reduces overall luminance •In amblyopia, VA same as or better than sound eye •In organic disease, VA worse with profound decrease •More consistent in strabismic than anisometropic amblyopes Decreased Contrast Sensitivity •Central visual acuity – the smallest high contrast sensitivity which can be detected •There is loss of high spatial frequencies which increases with the severity of amblyopia •It represents a neural loss of foveal function Eccentric Fixation •Develops in patients with dense amblyopia •A general area of viewing, not a single point •Present in monocular and binocular conditions Classification •Strabismic •Anisometropic •Due to high refractive errors •Deprivation Strabismic Amblyopia •Caused by constant unilateral suppression of cortical activity related to the deviated eye •Usually in constant tropias •Most common form Anisometropic Amblyopia •Usually identified through vision screening at school age •Hyperopic and astigmatic – only 1 – 2 d can produce it •Myopic >3d; -6d often results in severe visual loss Amblyopia Due to High Refractive Errors •Hyperopia > 5d •Myopia > 10d •Astigmatism > 2d Deprivation Amblyopia •Amblyopia ex anopsia •Medial opacities-congenital cataract; Peter’s anomaly •Congenital ptosis •Occlusion amblyopia •Unilateral worse than bilateral Amblyopia Treatment •Establish a clear retinal image •Correct ocular dominance Establishing a Clear Retinal Image •Cataract removal •Ptosis surgery •Corneal transplant •Full hyperopic correction for high hyperopes •Full astigmatic correction for meridional amblyopes Correct Ocular Dominance •Patching •Penalization Patching •Cover the sound eye to stimulate neurodevelopment of amblyopic eye •Full-time Occlusion -most effective

-for all but one waking hour Patching •Part-time – not as effective - when not tolerated; not practical - for maintenance occlusion Age Limits for Occlusion •8 years? 9 years?

…none.

•Try full-time occlusion for three months max. •Progress is slower in the older patient. Patching: Technique •Adhesive orthoptic patches- opticlude -wet well before removing •Eye pad with black cloth and micropore tape •Black cloth sleeve over glasses Occlusion Amblyopia •Reversal amblyopia •Prevention - see the patient in one week per year of life of patching, max. of 4 weeks •Be very careful in patching infants < 6 months: < or = 50% of waking hours 6 – 12 months: 80% of waking hours Penalization •Blurring the sound eye to force fixation to the amblyopic eye •Optical- overplussing lens such that sound eye is used for near Atropine Penalization •If emmetropic, only blurs at near •If hyperopic, blurs distance and near •Not recommended for dense amblyopia unless highly hyperopic The Ophthalmologist treats amblyopia but the primary care physician detects amblyopia. Vision Screening Purpose: to identify children with one or more of the following conditions: •Decreased vision in one or both eyes •Eye conditions which could lead to decreased vision •Strabismus (crossed or wall eye) •Other eye related conditions such as: ptosis, nystagmus, head tilt, etc. The best age for vision screening: As near as possible to the 3rd birthday Recognition Acuity at 3 years Observe for: •eye crossing •"wall" eye •nystagmus •droopy lid •abnormal head positions Recognition Acuity at 3 years •Thank you! STRABISMUS The angle bet visual and central pupillary line

Angle Kappa

A nasally centered pupillary light reflex gives the appearance of exotropia and is physiologic. A temporally displaced pupillary light reflex gives the appearance of esotropia and is uncommon, occurring in some cases of very high myopia.

Extraocular Muscles Spiral of Tillaux •The line of insertion where the rectus muscles insert in sclera gradually farther from the limbus beginning with the medial rectus at 5.5mm (range 3.0 to 6.0mm), inferior rectus 6.5mm, lateral rectus 6.9mm and superior rectus 7.7mm. •It is also the line of insertion of posterior Tenon's capsule which then proceeds to the limbus as the episclera fused with the underlying sclera. Recti The rectus muscles are each 40mm long. They receive innervation on the global surface at the junction of the middle and posterior 1/3 of the muscle. The pulleys are located on the orbital surface at the junction of the middle and posterior 1/3 of the globe. The pulleys are fibromuscular structures that act as functional origins of recti

Coronal view - normal location of pulleys Inferior Oblique Superior Oblique The S.O. has its functional origin in the trochlea. This unique structure allows an 8mm increase in the trochlear insertion distance in upgaze and an 8mm decrease in distance between the S.O. insertion and trochlea in downgaze. Action Action Blood Supply A long posterior ciliary artery travels from the back of the eye in sclera beneath the horizontal recti. The oblique muscles do not contribute to the blood supply of the anterior segment of the eye. lateral rectus •innervated by the sixth cranial nerve. •The nucleus is located in the brain stem and the nerve is uncrossed. superior oblique •innervated by the fourth cranial nerve which crosses to reach the muscle. •The nerve passes through the "stiff" tentorium making it susceptible to the shearing force produced by brain oscillation in closed head trauma. third cranial nerve Innervates •the medial rectus •superior rectus •inferior rectus •inferior oblique •levator palpebri. •The sympathetic nerve supply travels along the innervation to the inferior oblique. •The parasympathetic supply travels in the nasociliary nerve.

Principles and definitions •Primary position of gaze- looking straight ahead •Field of action- direction where muscle exerts greatest force •Agonist- muscle that pulls eye into direction of gaze •Antagonist- opposing muscle which relaxes •Synergistic muscles – muscles that have same field of action ex. RSR and LIO are synergists for upgaze

Sherrington’s law •Reciprocal innervation of antagonistic muscles •- synergists are stimulated and antagonists inhibited •Ex. Right gaze- RLR and LMR stimulated • RMR and LLR inhibited Hering’s Law •Equal innervation given to yoke muscles

•Yoke- a pair of agonists with same primary action •Ex . RLR and LMR are the yoke pair for right gaze •Importance: secondary deviation in paretic muscles •Ductions-monocular rotations •Versions- binocular rotations •Primary deviation- normal eye fixing •Secondary deviation – paretic eye fixing •Prism diopter-unit of angular measurement • 1 degree of arc = 1 pd Evaluation Cardinal Gazes Hirschberg Test Krimsky Phoria vs Tropia

•Heterotropia- manifest strabismus - present under binocular viewing conditions

•Heterophoria- latent strabismus - only after binocular vision is interrupted Cover Test •Cover-uncover Test – shows a manifest deviation e.g. esotropia •Alternate Cover Test – shows latent deviations too e.g. exophoria •Orthophoria- no shift on cover testing Cover Testing Pseudo-strabismus esotropia Accomodative Esotropia Bifocals for High AC/A Accomodative ET

Deviation varies in different fields of gaze •Duane’s •Brown’s •III N Palsy •VI N Palsy •IV N Palsy

Exotropia Hypertropia Incomitant Strabismus

Duane’s Type 1 The Etiology of Duane Syndrome •IIIrd N regenerates to lateral r. causing co-contraction of LR on attempted adduction Brown’s Syndrome IVth Nerve Palsy VIth Nerve Palsy Non-surgical: Fresnel Prisms Strabismus surgery Adjustable sutures