A. The vestibulo-ocular reflex has the shortest latency of all eye movements with a latency of 15msec. The purpose of the VOR is to stabilize the retinal image as the head moves so it must occur quickly.

E. -2.00 D. A far point that is reduced from infinity is more indicative for myopia. Using the equation 1/0.5m = 2.00 D. A +2.00 eye requires -2.00 D to return the far point to infinity.

D. Latent hyperopia (refractive error that is correctable with accommodation) is +3.00 D. Manifest hyperopia (refractive error that is present in subjective refraction) is +4.00 D.

C. Absolute hyperopia (hyperopia that cannot be neutralized with accommodation alone) is +3.00 D; the difference between the two values. Facultative hyperopia (amount of hyperopia neutralized by accommodation) is +2.00D; the total accommodative ability.

C. Accounting for your working distance (50cm = -2.00 D), the 90 (or vertical) meridian is plano while the 180 (or horizontal meridian) is -0.50 D. Using the most plus meridian as the sphere, the prescription should be plano -0.50 x 090.

D. The correct answer should be 60 since the clock dial equation is (lower number on the clock x30) which will give you in this case (2×30=60 degrees)

What is the Procedure of using a Lens Clock?
1) Multiply the smaller number (the lower number is always the number used in the clock dial equation) by 30 degree to find the orientation of the minus cylinder axis

D. Sherrington’s Law states that reciprocal muscles in the SAME eye will both be innervated to provide stability of eye position and gaez. Hering’s law states that yoked muscles in both eyes will receive equal innervation. Donder’s and Listing’s refer to unique orientations of the eye in space and how the eye achieves these positions.

C. To the LEFT. Recall COWS – cold = opposite, warm = same. As we know nystagmus is named by the fast phase (not the slow fixation period). Thus, since the nystagmus is in the same direction with warm water, we know it is to the left.

B. End-point nystagmus is noted in extreme position of gaze. It is not noted at other times. Caloric nystagmus refers to the use of warm or cold water to induce eye movement. Optokinetic is related to viewing fast moving or rotating objects as the eye attempts to fixate a target. Rotational refers to rotation of the individual’s body. Latent refers to nystagmus that appears when one eye is occluded.

C. Undershooting is the most common saccadic error. Recall that saccades are rapid, yoked eye movements to quickly move an image to the fovea. These eye movements are important in reading and spotting tasks.

B. There is an issue with the Superior Oblique of the right eye. To answer this question, you must implement Parks 3-Step. First, we note right hyper in primary gaze which indicates either RIR/RSO or LIO/LSR. Next is the head tilt. The patient is tilted to the right meaning RSR/RSO or LIO/LIR. Last, which gaze is the hyper worse? In this case left gaze which indicates RIO/RSO or LSR/LIR. RSO is the only muscle in all three.

A. Fixation disparity is measured under ASSOCIATED conditions. Associated is defined as when two eyes are focused on the same target and fusing images. The other options rely on disassociating the eyes to complete measurements.

C. The calculated AC/A is 3.6. The equation of note is AC/A = PD(cm) + WD(m)[Phoria @ N – Phoria @ D]. When plugging in values, Exo is considered “-” and Eso is considered “+”. Therefore, AC/A = 6.4 + .4(-8-(-1)) = 3.6. CAREFUL that PD is in centimeters.

C. Minus lenses indirectly test NEGATIVE fusional vergence. Adding minus lenses increases accommodation and convergence. In order to maintain images on the fovea,negative fusional vergence is required to overcome the changes. Prisms directly test the direction of their apex.

A. 10 pd BI. As we are calculating the prism necessary for exophoria, it is recommended to use Sheard’s Criterion. The equation is Prism = ⅔ Phoria – ⅓ Compensating Fusional Vergence. In this case, the phoria is 18Δ and the compensating fusional vergence (positive fusional vergence for exophoric patients) is the blur point of the BO measurement. To alleviate phoria we expect to move images to the fovea. Therefore the 10Δ will be BI. Remember this is total and NOT per eye.

B. The minus lens test is the only option that does not measure accuracy but instead measures amplitude.

B. 12.5 D. Hofstetter defines three equations: 1. Average Amp of ACC = 18.5 – 0.3(Age), 2. Minimum Amp of Acc = 15 – 0.25(age), 3. Maximum Amp of Acc = 25 – 0.4(age). For this problem, we use equation 2.

D. One would expect a low NRA. This is due to the reduced fusional vergence needed to keep eyes aligned. All other findings can be found in a CI patient. Other findings include: reduced positive fusional vergence, and a low lag/lead of accommodation.

C. One would expect a high LAG of accommodation as the patient does not have the ability to accommodate. The remaining options are expected findings in AI.

D is the correct response, having hyperopic aniso > 1.00
Diopter can lead to amblyopia in the eye with higher prescription, in this case OS which is +7.00.

Norms include:
ANISO: H >1.00, A >1.50, M >3.00; ISO: H >5, A >2.50, M >8.

B. Anisometropic hyperopia is more likely to cause amblyopia as one eye never receives a clear image. In patient with aniso myopia, there is a point of clarity for either refractive error. Strabismus first presents with diplopia but with time can become suppressed. Eso = nasal, Exo = temporal. Deep amblyopia is considered 20/100 – 20/400.

B. This is the definition of Harmonious ARC. Unharmonious ARC is when the angle of anomaly is less than the objective angle and occurs mostly post-strab surgery. Paradoxical is split into two types: Type 1 is subjective angle greater than objective – Type 2 is an eccentric fixation in the opposite direction of what is expected.

B. Maxwell’s spot, as well as visuoscopy and Hidinger’s brush, are used to measure eccentric fixation. 4 BO test is used for ocular alignment, such as in microstrabismus syndrome. Bagolini lenses are used for ARC. W4D is used for sensory status.

D. 22Δ LET. The normal Hberg position is at 0.5mm nasal. Any 1mm displacement past that is equal to 22Δ.

A/D. Both media opacities and higher refractive error at a longer test distance can both present with darker reflexes. The deviated eye in strabismus, as well as higher refractive error at 1 meter and retinoblastoma, present with brighter reflexes.

C. Suppression of the left eye. Placing a loose 4BO in front of the right eye causes a small movement of the right eye toward the apex of the prism. Due to yoked muscles movement, the left eye will also move. If the left eye is not suppressing, it should quickly re-fixated to target. If there is NO movement of either eye with lens placement, it is a suppression of the right eye. If the left eye does not refixate after a right eye shift, the left eye is considered suppressed.

D. Crossed diplopia. Recall that the right eye sees the red dots and the left eye sees the green dots. If the red dots were located to the right of the green, that is considered uncrossed (or ESO) diplopia. Red dots above or below the green are indicative of a hypertropia. A patient reporting only one set of lights indicates suppression of either eye. A report of 4 dots is what we hope for.

B. Accommodative esotropia is the most likely diagnosis at this time. There are a few pieces of information that are key. First, the infant is demonstrating an eye turn some of the time. This means there is either a stimulus to the eye turn or it may be a decompensated phoria. The second piece of evidence is the orthophoric position with +3.00D lenses. This indicates that when accommodation demand is low, the eye turn is not present (or reduced).

D. Wold Sentence Copy is an example of a VMI test. The Beery VMI is another example. Piaget and Gardner, as well as Standing Angels in the Snow, are examples of tests of visual spatial skills. Visual analysis encompasses 6 sub-categories focused on analyzing images of different complexities.

D. The Critical Period for development of clear, binocular vision is between 7 and 8 years of age. This is why it is critical to provide thorough eye examinations to young children. The earlier the diagnosis, the better outcome to treatment.

C. Duane retraction syndrome Type 1 as there is only an issue of aBDuction of the right eye. To remember, recall that you “count the D’s” to determine the diagnosis.

E, 4.5 years is roughly when a child should be able to draw and identify a square. Some important shapes to know include: Straight line near the end of 2 years of age, Circle at 3 years, and Triangle near 5 years.

A. Accommodative response is present at birth and reaches maturity at about 3 months of age. It is important to review key ocular motor and visual development milestones.

B. According to Piaget, object permanence indicates the beginning of the pre-operational stage (2-7 years). There are four stages: sensorimotor (0-2 years), pre-operational (2-7 years), concrete operations (7-12), and formal operations (12 years and older). Object permanence is the knowledge that an object still exists even if it is not in the same room.