VISION SCREENING 101

Dr. Thanh (Kai) Nguyen University of Florida 2005 Nova Southeastern College of Optometry 2009 You & Eyes 2011

You & Eyes www.youandeyes.com 407-658-6580

Importance of Wellness Eye Exam An important part of preventive health care Please note that a person can have “20/20” eyesight, with or without glasses, yet he/she may have an eye problem. Many eye and vision problems have no obvious signs or symptoms such as glaucoma, tumor, cancer, retinal detachment, and optic nerve/retinal diseases Early diagnosis and treatment of eye and vision problems Preventing vision loss Detection of many general health problems such as diabetes, high blood pressure, heart disease, infectious diseases, and vascular diseases.

Wellness Eye Exam Complete internal and external health check of the eyes Eye focusing, eye teaming, and eye movement abilities assessment Ocular muscles, blood vessels and nervous systems evaluation Risk assessment of eye diseases resulting from general health problems and family history of eye problems Refractive error (nearsightedness, farsightedness, astigmatism, or presbyopia) evaluation Dilated pupil posterior ocular segment evaluation

Vision Screening Intake Questionnaires Extra Ocular Muscle Test (EOM) Near Point Convergence (NPC) Accommodative Amplitude Suppression Test – Depth Perception Confrontation Field Test (CF) Color Vision Test Visual Acuity Test (VA)

Look for these common warning signs in children/teenagers Blurred and/or double vision One eye turning in or out Squinting, eye rubbing, or excessive blinking Red, sore, itchy eyes Headaches, dizziness, or nausea after reading Head tilting, closing or blocking one eye Avoidance of near work

Look for these common warning signs in children/teenagers Trouble seeing the board Book held too close to the eyes Confuses similar looking words Poor reading comprehension Tired and sleepy after reading Dislike reading Frequent loss of place during reading

Vision Screening Visual System Visual Acuity Test Color Test Suppression Test Confrontation Field Test Eye Teaming System (Convergence/Divergence) Near Point Convergence Extra Ocular Test Accommodative System (Focusing) Accommodative Amplitude

Visual System “20/20” Eyesight With or Without Glasses Healthy Eyes Refractive Errors Myopia Hyperopia Astigmatism

Anatomy of the eye

Myopia

Hyperopia

Astigmatism

Visual Acuity (VA) Test VA (cc) @ Distance 20/30 -1 OD @Near 20/20 OD 20/25 +2 OS 20/25 OS VA(sc) @ Distane 20/200 OD @Near 20/30 OD 20/100 -2 OS 20/20 OS CC = With Correction SC = Without Correction Stand at 20 Feet From Chart No Squinting Test One Eye At a Time Sometimes Patients Still Need Rx Even if Patients See “20/20’ - Hyperopia

Visual Acuity Test 30 E L G P T 25 S P H B E 20 D T C B O

Color Test OD: 14/14 OS: 12/14 #3,8 Age Limit: All Ages Test One Eye At a Time Require Good Vision EyeHandBook App High Rx, Retinal Disorders, Optic Nerve Diseases, Cataract

Color Test Number of Plate Normal Person Person with Red-Green Deficiencies Person with Total Colour Blindness and Weakness 1 12 2 8 3 X 5 4 29 70 74 21 6 7 45 9 11 16 Traceable   Protan Deutan Strong Mild 13 35 (3) 5 3 (5) 14 96 (9) 6 9 (6) Can trace two lines Purple Purple (red) Red Red (purple)

Suppression Test Require good vision - Need to wear glasses or contact lenses Test both eyes together Worth 4 Dot Right Eye – Red Filter – See 2 Dots Left Eye – Green Filter – See 3 Dots High Rx, Amblyopia, Strabismus

Suppression Test

Confrontation Field (CF) Test Gross Peripheral Vision Test Only Preferred Without Glasses FTFC OD, OS (Full to Finger Count) Age Limit: All Ages Test One Eye At a Time 80cm From The Patients Optic Nerve Pathway, Ocular Diseases

Confrontation Field Test

Extra Ocular Muscle (EOM) Test FROM OU (Full Range of Motion) Age Limit: All ages Test Both Eyes Together Check For Full Extension, No Double Vision, No Pain Perform Without Glasses Ocular Muscle Problems, Cranial Nerve Disorders, Compression

Extra Ocular Muscles (EOM)

Extra Ocular Test (SO4LR6)3

Near Point Convergence (NPC) Convergence Disorders Require Good Eyesight – Wear Best Correction Require a Small Target Test Both Eyes Together Start at 40cm Bring target close to patient’s nose until the patient reports blurry target, then double or you notice an eye turn outward, then pull target out until patient report single vision Measure the distances from the target to the eyes (Blurry Distance/Double Vision Distance/Single Vision Distance) Normal Value: 5-7cm (see double)/11cm (see single again)

Accommodative Test Donder’s Push Up Method Accommodative Disorders Need Small Target Test One Eye At a Time Start at 40cm Push Target Toward Eye Until Blurry Measure Distance From Target to Eye (Blurry Target to Eye) Require Good Eyesight – Wear Best Correction 1/Distance At Blur (For Example: 1/0.1m = 10D

The End! 407-683-8697 Dr.TKNguyen@gmail.com