Pediatric Vision Assessment Quiz

Stress Theory (Physics)

• Stress is the force that deforms a body.
• Strain is the result of stress.
• In everyday language, we say "under stress," implying the effect. But in physics, stress is still the cause.

Hans Selye's Stress Theory

• Stress is the body's response to a demand.
• Stressors are the factors that produce the body's response.
• The response of the body is non-specific to the demand.

Influences on Adaptation

• Stress affects individuals differently.
• Individuals have varying tolerances to stress.
• Stressors: type, persistence, intensity, concurrent conditions.
• Factors: genetics, external factors (temperature, pollution, noise), psychological factors (personality, attitude), prior conditioning.

Skeffington's Model of Vision

• The model emphasizes four key dimensions of vision:
• Centering (convergence): directing the body, head, and eyes toward a spatial area for processing information and attention to the external world.
• Antigravity (vestibular): internal balance, orientation, and spatial localization.
• Identification (accommodation): gathering the meaning from areas of selected attention (resolution, discrimination, differentiation, and determination of relationships between details)
• Speech-Auditory: analysis and communication of what is seen

Nearpoint Stress Model (Skeffington)

• Humans are not biologically suited for near-vision tasks.
• Near-vision tasks cause sustained concentration, immobilization, and mental effort which lead to a stress response.
• The centering process to localize is a more crucial and stronger individual drive than identification.

Nearpoint Stress Model (Efficient Reading)

• Accommodation and vergence need to localize at the plane of regard.
• The drive for vergence to be closer than accommodation leads to blur and diplopia — the stressor!
• Adaptation is the way out of this.

Nearpoint Stress Model: Choices

• Avoidance: the easiest solution.
• Inefficient visual function: avoidance can lead to ineffective reading.
• Accommodative or vergence adaptation: addressing the issue (e.g., accommodative or convergence insufficiency).

COVID Quality of Life (QOL) Questionnaire

• Developed in 1995 by a COVID committee.
• Ascribes to vision therapy, change in distance spectacle RX, and near point lenses.
• Original version had 30 questions; shortened version has 19.
• Advantages of survey: easy administration, low cost, standardized.
• Disadvantages: leaves no room for clinic elaboration.

COVID QOL Questionnaire Scoring

• Scoring system: points for 'always' (4), 'frequently' (3), 'occasionally' (2), 'seldom' (1), 'never' (0).
• Summing scores from each question to gain a total; scores above 20 suggest visual efficiency and/or perceptual disorder concerns.

Cover Test

• Used for unilateral and alternating tests to determine strabismus and phoria.
• Norms for distance and near vary.

Phoria Measurement (Von Graffe Method)

• Uses a phoropter for assessing lateral and vertical phoria.
• The patient must keep the letters clear.
• Norms for distance and near tests are available.

Near Point of Convergence

• Assesses convergence amplitude with objective and subjective tests.
• Repetition is critical for accuracy.
• Different target types are used, including those for accommodative testing (5cm break, 7cm recovery, penlight with red lens).

Smooth Vergence

• Measures the amplitude of the fusional vergence response in positive and negative fusional vergence.
• Assessment includes blur finding, accommodation, break finding and recovery.

Stereo Testing

• Evaluates the presence and degree of stereopsis.
• Methods include suppression check, local/contour stereopsis, Wirt circles, and Titmus instruments.
• The tests are used to see if peripheral stereopsis exists.

Prism Facility

• Measures the dynamics of the fusional vergence system while also tracking the ability to respond given periods of time.
• Evaluates the accommodative amplitudes and accommodative facility.

Accommodative Testing

• Amplitude methods such as push-up, pull away, and minus lens-to-blur.
• Facility methods include monocular and binocular.
• Response methods such as Monocular Estimated Method (MEM) and Fused Cross Cylinder (FCC).
• Additional methods include NRA/PRA.

Hofstetter's Formulas

• Formulas based on Donders and Duane's work on accommodation.
• The target is a single black line.
• Methods for minimum accommodation and average accommodation.

Accommodative Amplitude

• Push-up vs. pull-away measurements.
• Materials include near point cards or target systems (like tongue depressors).
• Monitoring patient response, including facial expressions, is important.
• Comparison to existing Hofstetter formulas.

Accommodative Amplitude (Minus Lens-to-Blur)

• Important issues related to minification due to varied minus lens powers are present.
• Adaptation to testing distance to 33cm rather than 20cm should be considered for better accuracy.
• Expected results should differ from push-up methods by about 2 diopters.

Accommodative Facility

• Failure to clear minus: accommodative insufficiency, convergence excess
• Failure to clear plus: accommodative excess, convergence insufficiency
• Record performance deterioration during testing, suppression occurrences, postural changes, patient complaints and attempts at moving cards.

Accommodative Posture (Monocular Estimated Method — MEM)

• Used to determine accommodative posture or lag, determining an appropriate near-vision Rx.
• Appropriate MEM card choices based on patient reading level (low-demand-large print vs. high-demand-small print) are crucial. Cards should be chosen closely to the actual patient reading level.
• Lens speed is crucial, as is checking both meridians for astigmatism.

Accommodative Posture: Recording

• Record the neutralizing lens power for each eye and if present the axis and amount of astigmatism.
• Record fluctuations or instabilities in the reflexes.
• Record the reading level and distance.
• Normal lag of accommodation is between +0.25 to +0.75 diopters.

Accommodative Posture

• Lag of Accommodation
• Lead of Accommodation

NRA/PRA

• Indirect measure of accommodation using binocular procedures.
• Procedures include having the patient in a phoropter, wearing habitual Rx, target (20/30 line at 40cm), sufficient illumination.
• Procedure involves the introduction of plus and minus lenses until the patient reports sustained blur.
• Expected PRA amounts: -2.37 +/- 1.00
• Expected NRA amounts: +2.00 +/ - 0.50

AC/A Ratio

• Measures the change in accommodation and vergence responses to accomodation changes or stimuli.
• Calculated using IPD (cm) + NFD (m) (Hn – Hf).
• Phoria measurement is repeated with either +/- 1.00.
• Calculated ratios are typically larger than gradient ratios due to under-accommodation and lag.

Eye Movements (Fixation)

• Includes direct observation, patient position (seated), and binocular/monocular targets.
• Grading involves steady fixation.
• Issues with fixation can arise after loss of accuracy.

Pursuit Testing (NSUCO)

• Direct observation test with the patient standing.
• Procedure involves moving an object clockwise and counter-clockwise.
• Grading criteria are based on ability, accuracy and body/head movement and on age/gender.

Saccade Testing (SCCO)

• Direct observation with the patient seated.
• Procedure involves moving a target horizontally, vertically and diagonally.
• Grading criteria are based on smooth pursuit, any gross issues with undershooting or overshooting and any uncontrolled head movement.

King-Devick Saccadic Test

• Measures reading eye movements (developmental growth).
• The procedure involves patients calling out 40 numbers horizontally (with errors and time assessed).

Developmental Eye Movement Test (DEM)

• Visual-verbal test involving vertical and horizontal arrays with timing and error evaluations.

Visagraph/Readalyzer

• Objective test to measure reading eye movements.
• Goggles with infrared sensors record eye movement.
• The tests looks at fixations, regressions, backward jumps, reading rate, fixation duration, span of recognition, directional attack and efficiency as assessed by a computer program. This results in a grade equivalent.

Prescribing Based Off the Binocular Vision Examination (Part 2)

• Prescribing principles, focusing on binocular vision examination data and treatment protocols.

Nearpoint Stress Model

• Describes the interconnected action of stress, vergence, accommodation, and the effect on reading.

Adaptation to Visual Stress

• Signs of this include the possible symptoms like exophoria, low or high MEM, fused cross-cylinder, and low absorption levels.

General Management Approach

• Discusses the need for plus at near, prism, and vision therapy.

Visual Hygiene

Treatment Strategies (Plus at Near)

• Examines whether plus at near alleviates symptoms.
• Findings that indicate the need for plus at near are outlined (low AA, eso at near, low PRA, high lag on MEM/FCC, NRA higher than PRA).
• Balanced amounts of plus and minus are considered for determining the tentative add power.

Treatment Strategies (Plus at Near): Acceptable Conditions

• Describes the conditions that generally respond well to plus at near treatments, including accommodative insufficiency, ill-sustained accommodation, and symptomatic esophoria at near.
• Performance testing with tentative added, using MEM, AA, stereo testing, VO star, or NPC.
• A trial period may be implemented to monitor progress with either loaner lenses or in-office use.

Case Studies (Various)

• Provides case examples of children with various ocular conditions, including symptoms, test results, diagnoses, treatment plans, and follow-up results.

Test your knowledge on pediatric vision assessments, including stereopsis, visual acuity, and retinoscopy results. This quiz covers various measurements and conditions that affect children's visual health. Perfect for those studying optometry or pediatric care.