1. M Evaluation of non seeing infant BY DR DIWA LAMICHHANE BIRATNAGAR EYE HOSPITAL, BIRATNAGAR 19 05 - 2013
2. Outline Epidemiology Visual development in infant Causes of non seeing infant Evaluation of non seeing infant
3. The prevalence of blindness increases from less than 0.01 per 100 in preschool- age children to 8.58 per 100 persons over the age of 60 . Bulletin of the World Health Organization, 63 (2): 375-386 (1985)
4. Nystagmus is absent in cortical blindness and is not found often in association with unilateral visual defects.
5. Visual development Complex maturation process Structural changes occur both in the eye & CNS Normal vision develops as a result of both genetic coding & experience in a normal visual environment Assessment Fixation target Blink reflex to bright light 30weeks after birth Pupillary light reflex 29- 31 wks of gestation
6. Visual development 6 weeks Make and maintain eye contact React with facial expression 2-3mths Interested in bright object Untill 4mths Disconjugate eye movements Skew deviation, sunsetting present as a transient deviation in new born
7. Visual development Sign of actual poor vision development Wandering eye movement Lack of response to familiar faces & objects Nystagmus Staring at bright lights Forceful rubbing of the eyes( oculodigital reflex )
8. Causes The causes of SVI and blindness may be: Prenatal Perinatal Postnatal
9. Causes.. Congenital anomalies Anophthalmos, microphthalmos, coloboma, congenital cataract, infantile glaucoma, and neuro-ophthalmic lesions Acquired during the perinatal period Ophthalmia neonatorum, ROP, & cortical visual impairment.
10. Most common causes Anterior segment anomalies Glaucoma Cataract Optic nerve hypoplasia Optic atrophy Leber congenital amaurosis Achromatopsia Congenital infection syndrome / TORCH Cortical visual impairment Delay in visual maturation ROP X-linked retinoschisis Congenital motor nystagmus Albinism Coloboma
11. Evaluation of normal infant
12. General history of the infant Parents or caretakers are asked routinely Young childs visual behavior with family members and at playtime Whether the child responds to a silent smile Enjoys silent mobiles Follows objects around the environment. Pertinent observations include strabismus, nystagmus, persistent staring, and inattention to objects.
13. Family history of ocular disease Such as blindness Poor vision Need for thick glasses Difficulty ambulating in dim Illumination Photophobia Color vision deficiencies Lazy eye or amblyopia Strabismus Nystagmus Leukocoria History of eye surgery.
14. Family history of systemic disorders That may be associated with ocular abnormalities Connective tissue Cardiovascular defects associated with Marfans syndrome Midfacial hypoplasia Arthropathy associated with sticklers syndrome Dental and umbilical abnormalities in riegers syndrome Urinary tract abnormalities in lowes syndrome Neurologic and skin abnormalities in the phakomatoses
15. Family history of systemic disorders Unusual physical traits, developmental delay, mental retardation, & early death Denial, illegitimacy, incest, paternal substitutions, & natural variability in expression of inherited disorders make the process even more difficult. A standard pedigree diagram of nuclear family
16. Male X linked disorder If sibling has similar condition not present in previous generations AR disease
17. Prenatal and perinatal history About the pregnancy, delivery, birth weight, gestational age, neonatal health. Maternal Illness, Infection, Radiation, Trauma Teratogenic potential of medications as ethyl alcohol, particularly in infants or children with dysmorphic features. The relatively free passage of substances from mothers circulation into breast milk provides infant with yet another route of ingestion. The importance of prematurity & its relationship to retinopathy of prematurity is well recognized.
18. Observing various components of the examination while taking history. Childs alertness, interaction with parents, head position, fixation & following ability, steadiness of gaze, gross alignment of eyes can usually be observed . Attention or crying it is sometimes best to interrupt history & begin more entertaining aspects of examination. Additional historical information can be obtained either during examination or after examination steps are completed. History..
19. General examination Childs general physical appearance, alertness, overall size, weight, body structure & interaction with adults accompanying child. Systemic disorders may be associated with ocular abnormalities, one should undress the child & examine various areas such as head, neck, integument, thorax, abdomen, genitalia, skeletal structure using inspection, palpation, & auscultation. The childs head size & shape eg. microcephaly & macrocephaly Unusual skull contours, such as plagiocephaly is related to certain types of strabismus.
20. Ocular examinations Position and size of the orbits Position of the globes which can usually be compared by looking down from over the childs forehead. Eye lids Palpebral fissures compared with respect to contour, size, location position & movement of the upper & lower eyelids, presence of epicanthal folds. Intercanthal & interpupillary distances is measured & compared with standard nomograms such as those listed in Smiths recognizable patterns of human malformation
21. Lacrimal system Size of tear meniscus, presence of epiphora, patency of lacrimal puncta, appearance of areas overlying lacrimal drainage system & lacrimal gland. Orbital structures Should be palpated & auscultated, with emphasis on areas of special concern. Ocular examinations
22. Visual acquity Infants & children up to the age of 2.5 to 3 years are generally unable to accomplish recognition visual acuity tests. It is evaluated by using objective techniques, such testing in clinical office setting is performed by observing eye movements that are produced in response to visual stimulation. The ability to fixate and follow a target is the principal clinical acuity test used to assess central visual function in infants & young children. Ocular examinations
23. Normal motor responses to visual stimulation in child consist of fast, voluntary, refixation saccades & slow, smooth pursuit movements that occur as eyes follow a moving target. Human face is generally strongest visual stimulus for young infant, even newborn infants intermittently attempt