Infant's vision
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This document discusses the importance of early vision screening and detection in infants. It provides recommended screening schedules based on age, describes typical visual development milestones in infants, and outlines common pediatric vision conditions and disorders. Screening tests are described to assess visual acuity, eye alignment and movement, color vision and other visual functions in infants. Treatment guidelines for common refractive errors like myopia and hyperopia are also mentioned. The overall message is that early detection through screening can help reduce vision loss in children.
Infant's vision
- 1. Infant’s Vision Héctor Santiago, OD, PhD, FAAO Inter American University of PR School of Optometry Bebé Héctor
- 2. Infant’s Exam Early detection reduces vision loss We can make the difference through early diagnosis and intervention
- 3. Recommended schedule AOA Pediatric Eye and Vision Examination Practice Guideline, 2000 Age Asymptomatic At risk Newborn to 6 months a 6 meses At 6 months At 6 m or as recommended 2 to 5 years 3 yo 3 yo or as recommended 6 a 18 years Before first grade and every 2 years Annually or as recommended
- 4. Visual acuity Preferential Looking (Forced choice) http://www.psych.ucalgary.ca/PACE/VA-Lab/Marcela/Pages/page9.html
- 7. 1 degree = 60’ 1’ = 60”
- 10. Visual Acuity 1 cycle/ degree (20/600 newborn) 3 cycles/ degree (20/200) at 3 m 6 cycles/degree (20/100) at 6 m 12 cycles/degree (20/50) at 12 m 30 cycles/degree (20/20) at 3-5 yo
- 13. Saccadic eye Movements Newborn: Horizontal hypometric Increased latency, less speed Normal by 1 yo
- 14. Accommodation Less than 2 months: Fixed accommodation, 30 cm More than 2 months: Good accommodation (worst for hyperopes and myopes)
- 15. Vergence 3 months: 70% have accurate convergence and divergence Primastic fusional vergence: Well developed by 6 months
- 16. Pursuits Presence for newborns if: Big stimuli ( > 12 degrees) Slow speed Present at 6-8 weeks
- 17. Optokinetic Nystagmus (OKN) Present at birth Poor nasal to Temporal Better temporal to nasal Symmetric by 3-6 m http://www.opt.indiana.edu/ce/infant/graphics/okn.jpg
- 21. Face perception http://www.psych.ucalgary.ca/PACE/VA-Lab/Marcela/Pages/page38.html
- 24. Color vision Cones : L (Red-Orange) , M (Yellow-Green), S (Blue) 1 week: Discriminate L and M Newborn to 1 month: Difficulties with S (blue) By 2 months: S are functional By 4 months: Normal trichromatic vision
- 25. focused correctly. Nearsightedness is a very common vision condition that affects nearly 30 percent of the U.S. population. Some evidence supports the theory MYOPIA
- 26. focused correctly. Common signs of farsightedness include difficulty in concentrating and maintaining a clear focus on near objects, eye strain, fatigue and/or headaches after close work, aching or burning eyes, irritability or HYPEROPIA
- 27. distances. People with severe astigmatism will usually have blurred or distorted vision, while those with mild astigmatism may experience headaches, eye strain, fatigue or blurred vision at certain distances. ASTIGMATISM
- 28. Disorders Pediatric Popualtion Desorden 6 m to 5 y -11 m 6 y to 18 yo Hyperopia 33% 23% Astigmatism 22.5% 22.5% Myopia 9.4% 20.2% Binocular disorders (Non strabismic) 5% 16.3%
- 29. Visual Disorders Type 6 m to 5 y - 11 m 6 y to 18 yo Strabismus 21.1% 10.0% Amblyopia 7.9% 7.8% Accommodative Disorders 1% 6% Retinal disorders 0.5% 2%
- 30. Equipment Trial case Prisms Lens bars Transilluminator Ophthalmoscope
- 31. Toys Brilliant colors With sound Without sound With movement Without movement
- 34. Hirschberg Test (binocular)
- 35. Measuring Angle Kappa and Hirshberg Catch attention Use source of light Occlude one eye: Angle Kappa Both eyes open: Hirschberg angle
- 36. Cover test
- 37. Extraocular motility Auditive-visual stimulus
- 39. Pursuits Visual, non-auditive stimulus
- 40. Convergence
- 41. 10 pd Base-Up Test Requires binocular attention An eye sees one image, a second eye sees an image displaced downwards If both images are clear, eyes switch from one to the other If one image is blurry, both eyes will look to the clear image
- 43. Confrontation (Visual Field) Use noisy stimulus to catch central attention Use interesting peripheral stimulus (eg puppet) Wait patiently for a response!
- 45. Bruckner Test
- 46. Bruckner Test Symmetry, brightness, clarity between eyes Subjective measure of visual acuity, deviation, refractive error
- 49. External Eye Exam Transilluminator 20 D lens or magnifier
- 50. Mohindra’s Refraction Monocular 50 cm distance Introduce lenses to neutralize Decrease by 1.25 D Use lens bar
- 52. Pearls Normal infants: hyperopic (Mean about 2.00 D) Emmmetropizatin between 2-5 yo 5-6 yo leptokurtic distribution, peak at low hyperopia
- 54. Anisometropia Anisometropic kids at risk of amblyopia Astigmatism > 1.50D - Hyperopic anisometropia > 1 D - Myopic anisometropia > 3 D
- 55. Prescription Anisometropia Correct if > 1D with acuity reduction Hyperopic anisometropia particularly harmful
- 56. Prescription guides Myopia: < 1 D generally ignore, only correct symptomatic and > 4 yo 1 to 3 D: correct if > 3 yo 3 to 5 D: correct > 1 yo
- 57. Prescription guide Hyperopia In general, correct if > 2.50D School children, correct hyperopias > 1 D
- 58. Internal eye exam Monocular ophthalmoscope DFE Fixation, pursuits and lack of aversion to occlusion well signs of equal visual acuity
- 59. Common cause lecucocoria Congenital cataracts Persistent primary hyperplastic Retrolental fibroplasia Tumors: retinoblastoma Coat’s disease Corioretinal Coloboma Old retinal detachment Intraocular inflammation: Toxoplasmosis
- 61. Persistent hyperplastic primary vitreous
- 64. Retinoblastoma Depósitos de calcio en retinoblastoma que pueden ser demostradas como radio-opacidades Pueden tener un origen único o múltiples orígenes en el mismo ojo
- 65. Retrolental fibroplasia Temporal retinal traction Paton et al - Introduction to ophthalmoscopy
- 66. Coat’s disease Anormalidad progresiva de los vasos acompañados de gran cantidad de exudados duros y muchas veces hemorragia. A la izquierda, la anomalía ha sido tratada con foto-coagulación.
- 67. Congenital Toxoplasmosis Cicatriz de toxo en el polo posterior. Nótese la pigmentación y la atrofia del epitelio pigmentario.
- 68. Toxocara canis Traction on retinal vessels Macular Granuloma with nematode Spalton –Atlas de Oftalmologia Clinica, 1984
- 69. Infant’s Vision Early detection is key Let’s work together to save vision – and may be life!
Editor's Notes
- #2: Que acción podemos realizar en nuestra práctica que tiene el mayor potencial en aumentar el número de pacientes que atendemos? Que acción podemos hacer que puede tener el mayor impacto en la salud visual de nuestros pacientes? Esta noche pretendo dar una contestación definitiva a esta preguntas.
- #3: Vamos a comenzar nuestro camino con una historia verídica. Es la historia de un bebé con uin defecto congénito. Y veremos como con la detección temprana se pudo hacer la diferencia en la vida de este bebé. (Presentación del video Vision and the Babys Brain (20 min).
- #5: Cuales son las destrezas visuales del bebé? Como podemos explorar el mundo de un ser incapaz de lenguaje? Sin duda, no hay un ser más delicado y débil en la naturaleza que el bebé humano. Ese ser humano tiene el mismo cerebro que el Australopithecus de hace 40,000 años. Sin embargo, cuando ese bebé se convierta en adulto tendrá que dominar una cultura en donde la información visual y auditiva son dominantes. Deberá aprender a leer, hablar, realizar procedimientos matemáticos. La primera función visual en que nos interesamos es la agudeza visual.
- #11: 30 ciclos/grado = 60 barras/ grado Por tanto: 1 barra = 1 minuto = 20/20
- #14: Saccades are rapid, ballistic movements of the eye that change fixation from one point to another. They reach near adult levels at about 3 to 4 months. Infants can make saccades more frequently than an adult - less than 200 msec between them vs. 200 to 250 msec. The actual velocity of an infant's saccades is almost as fast an adult's. The major difference between infant and adult saccades is that in the infant they begin somewhat later, and are smaller in magnitude. As a result, an infant may take over a second to fixate on a specific target. Sometimes infants display an oscillatory eye movement in which the eyes saccade away from an object before turning back to it. Such a movement in an adult would indicate pathology.
- #17: Smooth pursuit movements allow the eyes to maintain fixation on a moving target. Newborns lack this type of eye movement and instead make short saccadic movements to follow smooth targets. Smooth pursuit movements emerge at about 8 to 10 weeks, allowing the infant to track increasingly higher target velocities. Like adults, if the velocity of a moving target is too great to track, the infant will use a combination of saccades and smooth pursuit movements to keep up with the target.
- #20: The contrast sensitivity function (CSF) depicts an observer's sensitivity (i.e. 1/contrast threshold) to sinusoidal bar gratings of widely varied spatial frequency. Adult contrast sensitivity is greatest to intermediate spatial frequencies (about 2 to 4 c/deg). Lower and higher spatial frequencies require more contrast to be detected, resulting in an inverted-U function (see graph below). The highest spatial frequency can be resolved only at very high contrast and corresponds to the observer's acuity level. The contrast sensitivity function (CSF) depicts an observer's sensitivity (i.e. 1/contrast threshold) to sinusoidal bar gratings of widely varied spatial frequency. Adult contrast sensitivity is greatest to intermediate spatial frequencies (about 2 to 4 c/deg). Lower and higher spatial frequencies require more contrast to be detected, resulting in an inverted-U function (see graph below). The highest spatial frequency can be resolved only at very high contrast and corresponds to the observer's acuity level.
- #22: Infants seem to prefer looking at his/her's mother's face to that of a stranger. This preference might appear as early as 2 days after birth. Visual information appears to contribute to an infants' preference for the face of his or her own mother since it occurs even when viewed via a TV screen. Because of their poor contrast sensitivity for fine details (see section on Spatial Vision), this preference must depend on large, high-contrast stimuli. This information is provided by the mother's hairline/face boundary since if it is masked (e.g., with a scarf or bathing cap), the preference disappears. Infants preference for normally configured faces (below right) versus scrambled ones(below left) appears to develop at about 2 months of age.
- #23: Some form perception abilities appear to be present at or before birth. Even premature infants show preferences for patterned stimuli over plain stimuli. This suggests that the mechanisms underlying form perception are present sometime before birth. Given their poor acuity and contrast sensitivity, it is not surprising that infants show preferences for large patterns, high in luminance contrast (e.g. black and white). They also tend to prefer patterns with numerous features. For example, in the figure below, infants are likely to show a viewing preference for the stimulus in the top row over the bottom because it contains more elements (top left), is higher in contrast (top center) and/or is curved rather than straight (top right). At 3 to 4 months, infants are likely to attend to specific features within patterns. For example, when presented with a triangle, they may spend considerable time inspecting its vertices. A more global viewing pattern tends to emerge at 6 to 7 months.
- #25: Although the ability to discriminate different colors is not fully developed at birth, infants' sensitivity profile for different wavelengths is similar to that of adults. Their sensitivity is greatest to intermediate wavelengths (yellow/green) and less for short (blue) and long (red) wavelengths. violet 380–450 nm668–789 THz blue 450–495 nm606–668 THz green 495–570 nm526–606 THz yellow 570–590 nm508–526 THz orange 590–620 nm484–508 THz red 620–750 nm400–484 THz
- #64: Un coloboma es una fisura congénita de una parte del ojo. El coloboma de la coroide es una fisura en el coroide debido a una persistencia de una fisura fetal causando un escotoma en la retina. El epitelio pigmentado no esta presente , la retina sensorial esta presente generalmente pero es transparente y solo se pueden ver los vasos.
- #65: Después del melanoma maligno del coroide es la malignidad ocular mas frecuente y una de las mas comunes de la niñez. 1% de las muertes de la niñez son causados por el retinoblastoma.
- #66: Enfermedad de bebes prematuros expuestos a oxigeno suplementario. Causa vasoconstricción de y oclusión de las arterias y mas tarde una reacción de proliferación de vasos sanguíneos y reacción glial asociada causando cicatrización y tracción de la retina. Como los vasos temporales son os mas inmaduros en el nacimiento, son los mas afectados y halan la macula temporalmente
- #67: A teangiectasia (dilatacion de los capilares y arterias pequeñas causando una variedad de tumor (angioma) de la retina, mas comun en varones y unilateral. Estas teleangiectasias liquean exudados que pueden ser tan masivos que aparece una leucocoria. Puede terminar con desprendimiento de retina. Tratamiento: sellar telangiectasias con fotocoagulación laser o crioterapia.
- #68: Transmitida por la madre al feto. Causado por un parásito Toxoplasma gondii. Las lesiones son hiperpigmentadas corioretinales. Causado por ingerir alimento contaminado no bien cocido o limpieza de feces de gato. Puede causar retardación mental, microcefalia, estrabismo, nistagmo. Se usan sulfonamidas, esteroides y clindamicina. Puede tener episodios recurrentes.
- #69: Causado por jugar en lugares donde hay feces de perros. El parásito Toxocara canis, la larva pasa del estómago al sistema circulatorio y al coroide donde penetran a la retina o vítreo. Resulta en una masa blanca cerca de la macula y causar una reacción inflamatoria severa y leucocoria. Generalmente hay perdida visual severa con cataratas y atrofia del nervio óptico. Tratamiento con esteroides y drogas anytiparasiticas.