Primary Care Optometry & Refraction

Goodluck Doctors!

The primary care exam sequence can be grouped into four general areas :

• Case history

• Refractive status

• Binocular and Accommodative status

• Ocular health

Allows the examiner to learn the nature of the px’s problem regarding the px’s visual and ocular health.

ROLE AND SIGNIFICANCE

What are the 3 methods of history taking?

• Interview

• Questionnaire

• Combination of 1 & 2

Pertains to personal information of the patient.

PATIENT’S PROFILE

Includes complaints experienced or observed by the px. The examiner should ask more details about the px’s problem.

PROBLEM LIST

What are the common complaints of the px?

• Blurring of vision

• Headache

• Double vision ( diplopia )

• Light sensitivity ( photophobia)

• Itching

• Floaters

What are the basic components of case history?

• Patient profile

• Problem list

• Visual and Ocular History ( present and past )

• Family History

• Occupational and recreational visual requirements

What are the 3 sources of complaints?

• Accommodative

• Motor

• Intergrative

Blur or fluctuating vision at near point.

a. Accommodative deficiencies

b. Vergence deficiencies

c. Ocular Motility deficiencies

A. Accommodative deficiencies

Intermittent diplopia, closing or covering of one eye abd difficulty aligning columns of numbers.

a. Accommodative deficiencies

b. Vergence deficiencies

c. Ocular Motility deficiencies

B. Vergence deficiencies

Letters or words appear to jump, float, or move around asthenopia, headaches, or ocular fatigue with near work.

a. Accommodative deficiencies

b. Vergence deficiencies

c. Ocular Motility deficiencies

B. Vergence deficiencies

Eyes hurt, or tire while reading. Asthenopia, headaches or ocular fatigue with nearwok, excessive rubbing, blinking or tearing eyes. Intermittent blur of distance vision after near point activities.

a. Accommodative deficiencies

b. Vergence deficiencies

c. Ocular Motility deficiencies

A. Accommodative deficiencies

Excessive head movements when reading, frequent loss of place when reading, omission of words or skipping of lines when reading.

a. Accommodative deficiencies

b. Vergence deficiencies

c. Ocular Motility deficiencies

C. Ocular motility

Use of finger or a marker when reading, lack of comprehension when reading.

a. Accommodative deficiencies

b. Vergence deficiencies

c. Ocular Motility deficiencies

C. Ocular motility deficiencies

Distance between the centers of the entrance pupil of the eye. Also referred to as interocular distance (IPD) and pupillary distance (PD)

Interpupillary distance

To place the optical centers of spectacle lenses accurately relative to the eyes, either to avoid unwanted prisms or to produce desired prism. This is the clinical significance of the_____ ?

Interpupillary Distance

True or False

The near point PD is needed for proper placement of bifocal in the finished lenses?

True

What are the two methods of taking the PD?

1. Anatomical method ( far and near )

2. Catopric method

The px’s fixation is the examiner’s eye for distsnce PD and examiner’s nose for near PD.

A. Anatomical method

B. Catopric method

A. Anatomical method

True or False

If the PD for near is below 60 mm. Add 3mm to represent the PD for far.

False. Add 2mm

True or False

If 60 to 64 mm. Add 3mm for the PD for far.

True

True or False

If 65 and above add 5mm to make the PD for far.

False, add 4mm.

Factors to be considered to ensure accuracy in taking the PD.

1. Lines of sight of the patient should be horizontal to each other.

2. Line of sight of the examiner should intersect the measuring rule from identical angle for both reading.

A. 1 & 2 are correct

B. Only 1 is correct

C. Only 2 is correct

D. 1 & 2 is incorrect

C. Only 2 is correct.

The line of sight of the patient should be parallel to each other.

Factors be observed when taking the PD.

1. The examiner must not move his head when taking the examination.

2. The illumination should not be of such intensity that will distort the fixation of the patient.

3. While asymmetry exist, it is well to note the distance from the line of sight to the center of pupil.

4. The measurement is not accurate only when the PD of both the examiner and the px are approximately the same.

5. If faulty binocular fixation ( strabismus ) is present, it is necessary to take the reading of each eye separately while the other eye is occluded.

6. Where the two cornea are unequal, the centers of the pupil must be used.

A. All are correct

B. 1,2,3,4 are correct only

C. 1,4,5,6 are correct only

D. 2,4,6 are incorrect

E. 3,4,6 are incorrect

E. 3, 4, 6

3. The measurement is accurate only when the PD of both the examiner and the px are approximately the same.

4. The asymmetry exist, it is well to note the distance from the center of the nose to the center of the pupil.

   6. Where the two pupils are unequal size, the centers of the pupils must be used ( anisicoria )

What is the adult mean or average PD?

64mm

What is the children mean or average PD?

50-60 mm

It is the point of intersection of the lines of sight of the eyes when maximum convergence is utilized.

Near point of convergence ( npc)

Is the distance from the near point of convergence to the midpoint of the line connecting the center of rotation of the eyes.

Near point of convergence distance

The is the clinical use of ___. The measurement of the maximum convergence ability of the patient.

Near point of convergence ( ncp )

Patient’s with a remote npc may express symptoms such as :

Diplopia, frontal headaches, decreased reading comprehension, asthenopia, and occassionally fatigue

According to ___ (2008), the normal values of the NPC differ depending on the test target used.

Scheiman and Wick

What is the dioptric value of the near point of convergence?

Amplitude of convergence

Is equal to the reciprocal (in meters) of the near point of convergence multiplied by the patient’s PD in centimeters.

Amplitude of convergence

Measurement of the pupil size under constant stimulus.

Static pupil evaluation

Measurement of changes in the pupil size w/ changes in stimulus conditions either of light or accommodation.

Dynmic pupil evaluation

This is a clinical use of ____. Careful evaluation of the size of the pupil and mobility of the pupil provides the examiner information about the integrity and function.

Size of the pupil

True of False

The pupils are normally equal in size and vary from 2-4mm in diameter in bright light and from 4mm to 8mm in the dark.

True

True or False

Pupils with 1 mm difference in size in the light or dark or appear to be abnormally constricted or dilated, may indicate normal result.

False. Pupils with 0.5mm difference in size in the light or dark or appear to be abnormally constricted or dilated, may indicate presence of neurologic disease.

Normal size of the pupil

3-4 mm

Pupil size when iti s constricted - myosis ( hyperopia , astigmatism & presbyopia )

2mm

Pupil size when it is dilated ( mydriasis, myopia)

5mm

What is the mean and average value for pupil size under room light?

4.0mm ( average range : 2.5-5.0mm)

The mean value and range for pupil size under near total darkness?

+6.5mm ( average range : 5.0 to 8.5mm)

The mean value and range for pupil size under direct light?

3.0mm ( average range 2.0 to 4.5 mm )

Unequal size of the pupil.

Anisicoria

Is a convenient test for determining the presence of starbismus at Kea. It is particularly useful for a child on whom results with the unilateral cover test were questionable.

What is the other name of this test?

Fixation test / corneal reflex test.

Far or penlight held by the examiner at a distance of 40 cm.

Point of reference

If the location of the reflex is slightly nasal ward?

No deviatio. Normal.

If the location of the reflex is extremely nasal ward.

Exo deviation

If the location of the reflex is temporal side.

Eso deviation

Deviation of the corneal reflex from the center of the pupil is estimated. It is a quantitative diagnosis of strabismus.

Hirschberg method

Slightly nasal ward - 5 degrees = ____ prisms ?

10 prism

Pupillary margin — 15 degrees = ____ prisms?

30 prisms

Between pupillary & limbal area - 30 degrees = ___ prisms?

60 prisms

Limbal area - 45 degrees = ____ prisms?

90 prisms

Refers to the six extra ocular muscles of the eye responsible for eye movements to the different positions of gaze. What is the other name of this test?

Version test / motility test

Binocular, conjugate movements of the eyes allowing the lines of sight to move in a parellel direction.

Version

Movement of one eye in any direction.

Duction

Binocular movements with the two eyes moving synchronously & symmetrically in opposite directions.

Vergences

Rapid, voluntary or fixational movements of the eye.

Saccades

Used to determine the presence and absence of heterophoria and heterotropia.

Cover- uncover test

The distance when performing cover- uncover test?

Far ( 20 ft)

Near (16 inches)

If the eye moves in upon occlusion and moves out upon exposure, it indicates?

Esophoria

If the eye moves out upon occlusion, and moves in upon exposure, it indicates?

Exophoria

If the eye moves up upon covering and moves down upon exposure, it indicates?

Hyperphoria

If the eye moves down upon covering and moves up upon exposure, it indicates?

Hypophoria

Measures in diopters a px’s ability to change the focus of the eyes crystalline lens in response to a near stimulus. This can be done using the minus lens to blur method or push up technique.

Amplitude of accommodation

What is the hofstetter formula in minimum expected amplitude?

15- 0.25 (age)

What is the hofstetter formula in average expected amplitude?

18.5 - 0.30 (age)

Smooth movements of the eye while following an object in the difference positions of gaze.

Pursuit

What is the hofstetter formula in maximum expected amplitude?

25- 0.40 (age)

Superiority of one eye over the other in some perceptual or motor.

Dominant eye test

Constriction of the pupil in response to light stimulation of the retina.

Direct pupillary light response / reflex

Constriction of the pupil in the eye opposite to the eye stimulated with light.

Indirect ( consensual ) pupillary light response / reflex

Determine the quality of the change in the size of the pupil of the eye when looking at a near object.

Pupillary near response / response to accommodation

Used to detect unilateral anomalies of the retina and optic nerve pathway anterior to the lateral geniculate nucleus.

Swinging flashlight marcus - gunn test

Inability to distinguish certain colors. The defects in color vision result from the absence, malfunction or alteration of one, two or all of the photo- pigments.

Color vision test

What are the two classification of color vision deficiency

• Congenital / inherited

• Acquired

What are the two types of CVD

• Total colour blindness

• Partial colour blindness

Give the 5 causes of poor color vision

• genetics

• aging

• certain medications

• exposure to chemicals

• disease

also known as total color blindness?

monochromacy

is a moderately severe color vision defect in which the three basic color mechanisms is absent or not functioning.

dichromacy

blindness to red?

protanopia

blindness to green?

deuteranopia

blindness to blue

tritanopia

this is a tool for color vision test.

example: pseudo-isochromatic plates ( ishihara test)

Plate test

tool for color vision test.

example: fansworth D-15 Test ( dichromatous test)

Arrangement Tests

It is a standard instrument for the diagnosis of color vision defects

Anomaloscopes

Designed as practical means for measuring the ability of seamen, rallway personnel, and airline pilots to identify and discriminate navigational aids and signal.

Lantern Tests

lt is a color vision anomalies. Tend to cause yellow- blue anomaly?

Lesion of the choroids

lt is a color vision anomalies. Tend to cause either yellow- blue or Red- green anomaly.

Lesion of the retina

lt is a color vision anomalies. Tend to cause red-green anomaly.

lesion in optic nerve

An entire area that can bee seen when the eye is directed/ focused on a single point.

Visual Field Test

The clinical use is to measure the extent and distribution of the field of vision (central and peripheral’s side)

Visual Field Test

example of recording in confrontation test :

1. FCF : OD full, OS full

2. OD half, restricted temporally OS

3. Restricted upper right quadrant OD and OS

a. 1,2,3 are correct

b. 1 and 2 only is correct

c. 1 and 3 only is correct

d. 1, 2, 3 are incorrect

c. 1 and 3 are correct. OD full, restricted temporally OS.

asses the integrity of the visual field corresponding to the macular region of the retina.

Amsler Grid Test

give the 4 other names of retinoscopy

• keratoscopy

• shadow test

• skiascopy

• skiametry

give the 2 general types of retinoscopes

• spot

• streak

The apparent source is behind the mirror.

Plane mirror

Apparent source is in the front of the mirror.

Concave mirror