Binocular Vision

The ______________ visual direction is the line of sight going through the fovea.

primary visual direction

Is oculocentric a monocular or binocular phenomenon?

Monocular

Is egocentric a monocular or binocular phenomenon?

Binocular

The _____________ is a spatial representation of all points in space that are imaged on corresponding retinal points in the two eyes.

horopter

___________________ describes the area immediately around the horopter where objects are still seen as single and in depth (wiggle room).

Panum's fusional space

________________ is the area around a corresponding retinal point where are objects are still seen as single and in depth.

Panum's fusional area

Is Panum's fusional area or Panum's fusional space more related to points within the retina?

Panum's fusional area

Is Panum's fusional area or Panum's fusional space more related to points within object space?

Panum's fusional space

What test primarily distinguishes a phoria from a tropia?

A) Alternating cover test

B) Unilateral cover test

C) Maddox rod testing

D) NPC

B) Unilateral cover test

Which of the following is an abnormal cover test finding?

A) 4 XP at near

B) 2 XP at distance

C) 1 EP at near

D) 6 XP at distance

C) 1 EP at near

Do you neutralize an exophoria cover test finding with BI or BO prism?

BI

Do you neutralize an esophoria cover test finding with BI or BO prism?

BO

The _____________ phenomenon describes the patient's perception of movement opposite to the direction of deviation of an eye as it is uncovered.

The phi phenomenon

According to the phi phenomenon, during a subjective cover test would you expect a patient with an eso deviation to view the paddle motion in the same direction or opposite direction as the deviation of the eye as it is uncovered?

Opposite direction

According to the phi phenomenon, during a subjective cover test would you expect a patient with an exo deviation to view the paddle motion in the same direction or opposite direction as the deviation of the eye as it is uncovered?

Same direction

A patient with an esophoria an image moving to the ____________ (opposite of the inward turn of the eye) as the paddle is switched from covering the left eye to the right eye.

Left (opposite direction)

A patient with an exophoria an image moving to the ____________ (opposite of the outward turn of the eye) as the paddle is switched from covering the left eye to the right eye.

Right (same direction)

Which of the following are subjective ways to determine the magnitude of a deviation? (Choose 2)

A) Alternating cover test

B) Unilateral cover test

C) Von Graefe phoria

D) Maddox rod testing

C and D

A patient holds a maddox rod over their right eye oriented vertically. They report that they see the red line below the light source. What does this indicate?

A) LHT

B) RHT

C) XP

D) EP

B) RHT

A patient holds a maddox rod over their right eye oriented vertically. They report that they see the red line above the light source. What does this indicate?

A) LHT

B) RHT

C) XP

D) EP

A) LHT

What is the Maddox Rod test performed at 40 cm called?

Modified thorington

Which of the following is NOT measured under disassociated conditions?

A) Maddox Rod

B) Wesson card

C) Alternating cover test

D) Von Graefe phorias

B) Wesson card

Which of the following is NOT a device used to measure fixation disparity?

A) Mallet unit

B) Bernell lantern

C) Wesson fixation card

D) Maddox Rod

D) Maddox Rod

The amount of prism required to neutralize fixation disparity is known as ______________ phoria.

associated phoria (Not disassociated)

______________ fixation disparity occurs when the associated and disassociated phorias are in opposite directions.

Paradoxical fixational disparity

Which fixation disparity curve is seen in a sigmoidal shape and present in patients that are asymptomatic?

A) Type 1

B) Type 2

C) Type 3

D) Type 4

A) Type 1

Which fixation disparity curve is seen in an eso deviation?

A) Type 1

B) Type 2

C) Type 3

D) Type 4

B) Type 2

Which fixation disparity curve is seen in an exo deviation?

A) Type 1

B) Type 2

C) Type 3

D) Type 4

C) Type 3

Which fixation disparity curve is seen is associated with unstable binocular vision and will often have symptoms of aniseikonia and poor sensory fusion?

A) Type 1

B) Type 2

C) Type 3

D) Type 4

D) Type 4

What is the formula for calculated AC/A?

PD (cm) + Near fixation distance (m) (Near phoria- Distance phoria)

Does BI prism or BO prism test NFV?

BI prism

Does BI prism or BO prism test PFV?

BO prism

Does plus lenses or minus lenses indirectly test PFV?

Plus lenses

Does plus lenses or minus lenses indirectly test NFV?

Minus lenses

The blur point during smooth vergences represents _____________.

A) Limit of fusional vergence only

B) Limit of accommodative vergence only

C) Limit of accommodative and fusional vergence

D) Limit of proximal vergence only

A) Limit of fusional vergence only

The break point during smooth vergences represents _____________.

A) Limit of fusional vergence only

B) Limit of accommodative vergence only

C) Limit of accommodative and fusional vergence

D) Limit of proximal vergence only

C) Limit of accommodative and fusional vergence

What are the expected findings (Morgan's norms) for Distance BI smooth vergences?

-----/7/4

What are the expected findings (Morgan's norms) for Distance BO smooth vergences?

9/19/10

What are the expected findings (Morgan's norms) for Near BI smooth vergences?

13/21/13

What are the expected findings (Morgan's norms) for Near BO smooth vergences?

17/21/11

Is Sheard's or Percival's criterion more effective for prescribing prism in patients with an exophoria?

Sheard's criterion

Is Sheard's or Percival's criterion more effective for prescribing prism in patients with an esophoria?

Percival's criterion

Which criterion states that the compensatory fusional vergence reserve should be at least twice the demand of the phoria?

Sheard's criterion

A patient has 15 pd of exophoria at near and vergence ranges of 17/25/18 BI and 6/9/4 BO. What is the amount of prism that should be prescribed based on Sheard's?

A) 4 pd BO

B) 4 pd BI

C) 8 pd BO

D) 8 pd BI

D) 8 pd BI

What is the formula for prescribing prism using Sheard's criterion?

2/3 phoria - 1/3 (compensating fusional vergence)

Exo phoria= BO blur/break point

Eso phoria= BI blur/break point

Which criterion states that the smaller fusional vergence reserve should be at least half the greater fusional vergence reserve?

Percival's criterion

What is the formula for prescribing Rx using Percival's criterion?

1/3 (greater vergence) - 2/3 (lesser vergence)

A patient has 10 pd of esophoria with BI vergence 6/10/4 and BO vergence 21/28/22, what is the amount and direction of prism prescribed using Percival's criterion?

A) 3 pd BO

B) 3 pd BI

C) 12 pd BO

D) 12 pd BI

A) 3 pd BO (Remember BO prism is prescribed for eso deviations)

What prism is alternated during vergence facility? (Choose 2)

A) 12 BO prism

B) 12 BI prism

C) 3 BO prism

D) 3 BI prism

A and D

The expected findings for a NPC is a ___________ cm break, and ___________ cm recovery.

5 cm break, 7 cm recovery

Which of the following does NOT test the amount of accommodation present (amplitude)?

A) Push-up

B) Pull-away

C) FCC/BCC

D) Minus lens test

C) FCC/BCC

Which of the following does NOT test the accuracy of the accommodative system?

A) Nott's retinoscopy

B) MEM

C) NRA/PRA

D) MAF

D) MAF

Which of the following tests the flexibility of the accommodative system? (Choose 2)

A) Push-up

B) Pull-away

C) MAF

D) BAF

C and D

What is Hofstetter's formula for the average amplitude of accommodation?

18.5 - 1/3 (age)

What is Hofstetter's formula for the minimum amplitude of accommodation?

15- 1/4 (age)

What is Hofstetter's formula for the maximum amplitude of accommodation?

25 - 0.4 (age)

Does the push-up test tend to overestimate or underestimate the amplitude of accommodation compared to other methods?

Overestimate due to RDM

Using the minus lens method, a patient first experiences sustained blur at -3.00D. What is their amplitude of accommodation?

5.50D (Add +2.50 to account for working distance of 40 cm)

Which amplitude of accommodation test requires you to add the working distance (+2.50D) to your findings?

A) Push-up test

B) Pull-away test

C) Minus lens test

D) MEM

C) Minus lens test

Does the minus lens test tend to overestimate or underestimate the amplitude of accommodation?

Underestimate

The expected findings for BAF is approximately _________ cpm.

8 cpm

The expected findings for MAF is approximately __________ cpm.

11 cpm

Which of the following is a binocular test that assesses accommodation?

A) Minus-lens test

B) Push-up test

C) MAF

D) MEM

D (Binocular!!)

What are the expected findings of MEM?

A) Plano

B) +0.25 to +0.50

C) +0.75 to +1.00

D) > +1.00D

B) +0.25 to +0.50

Do you expect a patient to have a slight lag or slight lead of accommodation on MEM?

Lag

For FCC, if the horizontal lines are sharper at the beginning of the test, do you add plus lenses or minus lenses until both the vertically and horizontally oriented lines are equally sharp?

Plus lenses

For FCC, if the vertical lines are sharper at the beginning of the test, do you add plus lenses or minus lenses until both the vertically and horizontally oriented lines are equally sharp?

Minus lenses

What are the expected findings for FCC of a non-presbyope?

A) Plano

B) -0.50 to Plano

C) +0.25 to +0.75

D) > +1.00

C) +0.25 to +0.75

Does NRA indirectly test PFV or NFV?

PFV

Does PRA indirectly test PFV or NFV?

NFV

Does NRA relax accommodation or stimulate accommodation?

Relax accommodation

Does PRA relax accommodation or stimulate accommodation?

Stimulate accommodation

A patient has a FCC of +1.00 , NRA +1.50, PRA -1.00. What is the patient's tentative ADD?

+1.25D

_________________ is a group of non-specific symptoms including blurred vision, intermittent diplopia, eye pain, eye strain or fatigue, and headaches that occur during or after the completion of visual tasks.

Asthenopia

Which binocular vision disorder is characterized by an exo deviation greater at near >>> distance and a low AC/A ratio?

Convergence insufficiency

Which of the following would you NOT expect in a patient with Convergence insufficiency?

A) Larger exophoria at near than distance

B) High NRA findings

C) Receded NPC

D) Unable to clear plus lenses on BAF

B (Low NRA findings)

Does a patient with Convergence Insufficiency primarily have difficulty with PFV or NFV?

PFV

_________________ is a binocular vision disorder similar to Convergence Insufficiency except it is primarily characterized by an accommodative insufficiency with CI characteristics.

Pseudo-convergence insufficiency

Would you expect plus lenses to help with NPC in a patient with a CI or Pseudo-CI?

Pseudo-CI

Which of the following would you expect in a Pseudo-CI patient but NOT a true CI patient?

A) Decreased amplitude of accommodation

B) Near exophoria

C) Low NRA

D) Unable to clear plus on BAF

A) Decreased amplitude of accommodation

What are two key differentials in a patient that presents with sudden symptoms of a Convergence Insufficiency? (Choose 2)

A) Horner's syndrome

B) Myasthenia Gravis

C) Multiple sclerosis

D) Toxoplasmosis

B and C

Which of the following is the LEAST common non-strabismic binocular vision disorder?

A) Convergence insufficiency

B) Convergence excess

C) Divergence insufficiency

D) Divergence excess

C) Divergence insufficiency

Which of the following is the MOST common non-strabismic binocular vision disorder?

A) Convergence insufficiency

B) Convergence excess

C) Divergence insufficiency

D) Divergence excess

A) Convergence insufficiency

Which of the following is NOT associated with Divergence Insufficiency?

A) Greater esophoria at distance than near

B) Low AC/A

C) Non-comitant eso deviation

D) Reduced NFV at distance

C (comitant)

Which CN palsy is the closest differential to Divergence Insufficiency?

A) CN 3 palsy

B) CN 6 palsy

C) CN 4 palsy

D) CN 5 palsy

B) CN 6 palsy

Is Convergence Insufficiency or Convergence Excess associated with a higher AC/A ratio?

Convergence excess

Does a patient with Convergence excess primarily have reduced PFV or NFV ranges?

NFV ranges

What is the most common symptom associated with divergence excess?

Intermittent diplopia

Which of the following would you LEAST expect in a patient with a basic exophoria?

A) Reduced PFV ranges

B) Low AC/A

C) Reduced NRA

D) Inability to clear plus lenses on BAF

B (Normal AC/A)

Would you expect more of a lag of accommodation on MEM in a patient with Convergence Insufficiency or Convergence Excess?

Convergence Excess

Skipping lines while reading, diplopia, and a head tilt are all signs/symptoms most likely associated with which BV condition?

A) CI

B) CE

C) Vertical phoria

D) Divergence excess

C) Vertical phoria

Which of the following would you LEAST expect in a patient with Fusional vergence dysfunction?

A) Reduced accommodative testing

B) Reduced NFV ranges

C) Reduced PFV ranges

D) Normal phoria measurement at distance and near

A (Near)

Would you expect a patient with Fusional vergence dysfunction to have more abnormal BAF or MAF results?

BAF (accommodative function is normal)

Which of the following patients will fail BAF and MAF testing?

A) Fusional vergence dysfunction

B) Convergence insufficiency

C) Accommodative infacility

D) Convergence excess

C) Accommodative infacility

Which of the following is the LEAST likely to be found in a patient with Accommodative insufficiency?

A) Reduced PRA

B) Reduced amplitude of accommodation

C) Inability to clear plus lenses on MAF and BAF

D) High lag on MEM

C (minus lenses)

Will a patient with accommodative insufficiency have a lag or lead of accommodation on MEM?

Lag of accommodation

Will a patient with accommodative insufficiency have a more reduced NRA or PRA?

PRA

Will a patient with accommodative excess have a more reduced NRA or PRA?

NRA

Will a patient with accommodative excess have a lag or lead of accommodation on MEM?

Lead of accommodation

Is the inability to clear plus lenses on BAF and MAF more characteristic of Accommodative insufficiency or Accommodative Excess?

Accommodative Excess