Clinical Optometric Procedures: Patient Profile And Case History

Clinical Optometric Procedures: Patient Profile And Case History

CHAPTER 2 – PATIENT PROFILE AND CASE HISTORY

• This chapter will include a review of:
• Patient profile
• Case history

PATIENT PROFILE

A patient’s profile is essential in every eye exam. It involves the extraction of information on the demographics of the patient and their profile in terms of his or her family life, education, marital status, etc. It has been suggested that a patient profile will allow the practitioner to be effective in providing patient care if he or she has knowledge of the patient’s profile. The demographic information extracted facilitates future communication with the patient. In addition, the significance of the information gathered in this part of the examination is linked in large part to susceptibility to normal or abnormal conditions of vision or ocular health. For example, a patient who is approximately 50 years of age is likely to complain of near vision problems due to age related changes in focusing ability at a near distance (presbyopia). In the broader sense, information elicited also informs the practitioner’s differential diagnosis or formulation of a tentative diagnosis.

• Information extracted includes the following aspects:
• Name of patient
• Address
• Contact details
• Age
• Occupation
• Race/ethnicity
• Gender

 Hobbies/Lifestyle

• Education level
• These aspects are the first that are recorded in the patient record card (Table 2.1)
• Table 2.1 Patient profile aspect of the record card
• (Adapted from Clinical Procedures in Primary Eyecare Care: DB Elliot)

EYE EXAMINATION RECORD CARD

• PX ID

First name: Age Date:

Surname D.O.B.: Gender:

• Address: Contact number:
• Occupation:
• Hobbies: Race: International Centre for Eyecare Education

CASE HISTORY

• The Case History comprises a numerous aspects, viz.
• 1. Communication
• 2. The Chief Complaint
• 3. Patient’s Ocular History
• 4. Patient’s Ocular Health
• 5. Medications
• 6. Allergies
• 7. Family Ocular and Medical History
• 8. Vocational And Avocational visual Requirement

Introduction

Generally, case histories are taken at the beginning of a consultation. However, with experience the eyecare practitioner will notice that history taking continues throughout the examination as more information arises from conversations, occurring during the course of the examination. A case history should be taken in an appropriate location so that the patient is free to provide as much information as they can without any apprehension and respectful to the patient’s privacy. Ideally the practitioner should be facing the patient and should be positioned at about the same level. Room lights should be on fully. These simple guidelines will allow the patient to be more comfortable with the eyecare practitioner and establishes a good rapport with the patient.

• Main Objectives of a Case History
• 1. To elicit reasons for visit
• 2. To ascertain patient’s expectations

3. To acquire relevant background information 4. To determine the specific tests or procedures that should be performed during the examination 5. To form a tentative diagnosis

1. Communication

Figure 2.1 Communication

• Greet the patient with confidence. Introduce yourself. Be professional
• Establish a relationship of trust
• Show genuine interest
• Be courteous and respectful
• Ask open-ended questions. For example, an open ended question would be: “what difficulties are you

experiencing with your vision?” while a closed-ended question would be: “can you see clearly at distance?”

• Open-ended questions (open probing) are more likely to elicit useful information, e.g. ‘How does your eye

feel?’, rather than ‘Does your eye feel painful? If necessary, list symptoms or conditions to elicit specific information. Generally, asking questions which can be answered by a simple ‘yes’ or ‘no’ (closed probing) should be avoided, unless such a response is all that is sought.

To ensure that a comprehensive case history is obtained, questions should be asked in a logical sequence.

Repetitive or redundant questions avoided. Questions should be asked in a clear and concise manner. The use of jargon and technical terms must be avoided under all circumstances. Either a standard form or a structured approach can be employed.

There are six elements that are essential in a case history. They include: The chief complaint, patient’s medical history, visual and ocular history, medication and allergy history, family ocular and medical history and vocational and avocational visual requirements.

2. The Chief Complaint

The chief complaint is usually the primary reason for the patient seeking consultation. The patient’s chief complaint may be a symptom that is concerning them. One may be able to elicit the chief complaint by asking:

• “What is the reason for your visit?’’
• “What brings you to the practice today?’’
• “What seems to be the problem?’’

How to explore the Chief Complaint?

Once the chief complaint(s) has/have been elicited, more details must be elicited from the patient. Depending on the complaint the following questions will help gather detailed information.

For example, if the patient comes in complaining of a HEADACHE, the information gathered about headache would cover the following aspects which can be remembered by using the pneumonic DR. FALLOPPES. The pneumonic is elaborated as follows:

Description of the complaint/symptoms: What is the main complaint?

• Duration: How long does it last? Sometimes symptoms can present themselves for short periods of time due

to their association with other systemic conditions. For example, migraine sufferers would usually experience a visual aura that lasts for approximately 20 minutes before the headache presents itself

• Relief or remitting factors: What relieves it? Both of these factors would contribute to one establishing an

appropriate aetiology or tentative diagnosis for the patient.

• Frequency: How often does it occur? It is important to determine the periods of exacerbations and

remissions of the signs or symptoms presented by the patient

• Associated signs or symptoms: the practitioner must be aware of other associated signs and symptoms to

the patient’s chief complaint. e.g. headache follows loss of vision)

• Location: Where is the sign of symptom manifested? For example, headaches can have a specific location,

e.g. temporal, frontal, and occipital, etc. Blurred vision can be at a particular distance, e.g. distance or near, or in some cases at both distances International Centre for Eyecare Education

• Laterality: e.g. right, left, or both eyes?
• Onset: When did the symptom(s) start? This will help in deciding the aetiology of the condition. For

example, a sudden loss of vision may be associated with a vascular problem. A gradual loss of vision may be associated with a cataract

• Pain: Is there pain associated with the main complaint. If it is reported, the practitioner should probe further

to determine if it is dull, dull, sharp, piercing, radiating, etc.

• Prescription medication: Does the patient take any prescription medication? If the patient is doing so,

what is the regimen, its regularity, is there any abuse of medication, etc.

• Exacerbating factors: Are there any factors or circumstances that tend to make the symptom experienced

worse?

• Severity: How severe is the sign or symptom being experienced? One may ask the patient to rate the

severity of the problem on a scale from 0 to 10 with 0 being minimal discomfort and 10 being unbearable and debilitating. This can be especially significant when investigating a complaint of pain.

Regardless of the chief complaint however, the practitioner must still explore other aspects of blurred vision, flashes and floaters, etc.

An example of a patient who complains of BLURRED VISION Routinely, patients should be asked if they have experienced any visual symptoms. Since blur may be due to a range of causes other than uncorrected refractive error, it is necessary to follow-up a positive response to blur by seeking further details.

• Description of the complaint/symptoms: BLURRED VISION
• Duration: Is the blurred vision constant or transient (lasting only a couple of minutes to hours or days only).
• Relief or remitting factors: Is the vision less blurred when the patient moves closer or further from the task

at hand.

• Frequency: Does the blurred vision last for long periods of time or is it unchanging? If it does change as in

the case of diabetic patients, it can be related to episodes of high blood sugar levels.

• Associated signs or symptoms: Does the patient squint to make the vision better creating a pinhole effect
• that has a tendency to improve vision slightly?
• Location: Is this blurred vision at distance or near?
• Laterality: Is the blurred vision bilateral, unilateral, is one eye worse than the other, etc.?
• Onset: Did the blurred vision occur gradually like in the case of age related changes or did is occur suddenly

as in the case of a retinal blood vessel occlusion or a vascular problem?

• Pain: Is there pain associated with the blurred vision? The patient should rate its severity.
• Prescription medication: Does the patient take any prescription medication that could account for the visual

disturbance? In the case of blurred vision, it can be related to the ocular side-effects of the medication.

• Exacerbating factors: Does the blurred vision get worse at various times of the day? For example, myopes,

tend to have greater difficulties with their vision at night or under conditions of low illumination.

• Severity: How severe is the blurred vision? The patient’s function may be a good indicator of the severity of
• the symptom.

Likely aetiologies for blurred vision include

 Ametropia/Presbyopia

• Night myopia
• Malingering International Centre for Eyecare Education
• Ocular disease conditions, e.g. cataracts, retinal disease, optic nerve diseases
• Amblyopia
• Accommodative dysfunction
• Constant distance and near blur could be refractive such as astigmatism
• Constant distance blur could be refractive such as myopia
• Intermittent near blur could be refractive such as moderate hyperopia
• Constant near blur – Presbyopia or high hyperopia
• There may be other causes of blur or even multiple causes compounding one another
• Other chief complaints are explored in a similar manner.
• Possible chief complaints could include
• Decreased vision
• Headache
• Eyestrain/asthenopia
• Itching
• Burning/stinging eyes
• Tearing
• Foreign body sensation
• Double vision (diplopia)
• Flashes
• Floaters

Appendix III contains a list of the various aetiologies of visual and ocular symptoms: Adapted from Clinical Procedures in Optometry: Eskridge et al.

3. Patient’s Ocular History

• Last eye examination: When? By whom? Outcome? This aspect of enquiry will provide the practitioner

information about the patient’s knowledge of their visual status, the progression of the condition from the last examination and regularity with which the patient is monitoring their visual status, especially in those patients where systemic conditions can have detrimental effects on a patient’s visual status.

• It is important to have knowledge of previous ocular disease or trauma/injury. This aspect of investigation

would provide the practitioner with information regarding possible changes that could have resulted since the last visit, the visual and functional outcomes of conditions previously diagnosed and possible complications that could ensue.

• An ocular surgery history provides information on what condition the eyes may be found in at examination

time for example if they are aphakic or pseudo-phakic or had any refractive error surgery, etc.

• Any history of strabismus or Amblyopia.

For each condition reported the optometrist must ask when the condition was diagnosed and what its current status is.

Previous prescriptions including spectacles or contact lenses One needs to explore the type or purpose of the prescription, age when the Rx was first worn, the age of the current Rx, the patient’s subjective assessment of current Rx (is it still helping or not).

• Ascertaining when the patient’s first vision correction was prescribed. This will provide information on the

onset of their refractive error.

• The date of the patient’s current prescription will give an indication of how stable their refractive status is. A

comparison can be made between their current and new prescriptions. A sudden change in refractive state requires further investigation.

• Determining the wearing schedule or regimen of the patient’s current spectacles (e.g. reading only, or

distance only, or both distance and near) may influence the type of lenses prescribed. The prescription is also influenced by the characteristics of their previous lenses, especially powers, prism (if any), materials, tints, etc.

4. Patient’s General Health or Medical History This should explore the existence of previous and current health problems. This should include the following:

heart or kidney disease, high blood pressure, diabetes, arthritis, general fitness, headaches (those not related to vision) or any other systemic condition.

Patients who have heart disease, high blood pressure (hypertension) and/or diabetes are at a higher risk of retinal changes that can have a signification effect on vision.

• Last medical examination: When? By whom? Outcome? This would provide the practitioner with information

regarding the regularity with which they are monitoring their health status and its possible effect on the patient’s visual status.

5. Medications and Allergies

Specific information should be elicited, namely: drug name, purpose, dosage, compliance, side effects and the duration of the treatment. Taking note of these drugs would alert the practitioner to the possibility of the nature, course and ocular side-effects/complications of the drugs and their associated conditions.

Some medications have ocular side effects that may account for symptoms of dry eye, burning eyes or, in some cases, decreased amplitudes of accommodation resulting in problems at near, etc. It is therefore important for the practitioner to be familiar with the various drugs, its mode of action and effects and side-effects. If the practitioner is unfamiliar with the drugs used at the time of the eye examination, looking up at the relevant information is necessary.

Allergies may cause ocular irritation. Patients will often report itchy, watery and red eyes which can be attributed to allergies. Address how the patient has sought relief/treatment. These could have implications on contact lens wear and the presentation of certain symptoms. One should note the cause of allergy, if it is environmental or due to a medication.

6. Family Ocular and Medical History Family ocular history: glaucoma, low vision/blindness, significant refractive errors (exclude Presbyopia). This aspect of the case history is important because of the genetic implications of certain inherited conditions like retinitis pigmentosa for instance. Patients with any family ocular history of disease should receive a comprehensive ocular health examination to rule out the presence of the same condition in the patient.

Family health history: heart / kidney disease, high blood pressure, diabetes, etc. Who suffers from the condition (this is a factor that is considered with respect to genetic inheritance) like mother, father, sibling(s), grandparents International Centre for Eyecare Education (maternal or paternal side), etc. How long have they had the condition and what treatment is being used? Again, the implications of this area of questioning are based on the genetic implications for the patient.

7. Vocational and Avocational Visual Requirements This will guide the practitioner to take note of the patient’s special needs and prescribing accordingly, for example,

• Lighting conditions
• Computer monitor use
• Print size(s)
• Working distance(s)
• Safety/eye hazards

In certain specialty areas, like that of low vision for instance, these aspects of the case history are especially important to ensure that the individual is able to remain as productive and functional as possible. In addition, closer review of these factors could indicate to the practitioner if certain environmental or physical settings can be changed without the need for or dependency of the patient on spectacles.

Careful consideration of all of the aspects listed above can lead the practitioner to formulating a tentative diagnosis which can be confirmed or refuted by performing clinical testing. Finally when considering the history and testing the practitioner is able to arrive at a final diagnosis. The patient profile and case history is therefore one of the most vital aspects of the clinical assessment since it provides direction to the practitioner in terms of investigation and management or referral.

Refer to Appendix IV for a draft Record Card (Adapted from DB Elliot: Clinical Procedures in Primary Eye Care) Table 2.1 Common Abbreviations used in recording the case history (Source: Clinical Procedures in Primary eye care: DB Elliot) Px (or Pt) Patient Rx Prescription

• DS Sphere DC Cylinder
• CC Chief Complaint DV Distance Vision

NV Near Vision h/a Headache

R Right L Left

• RE (or OD) Right Eye LE (or OS) Left eye
• B (or binoc) Binocular BE Both eyes

With Without

• 1/52, 3/52 1 week, 3 weeks 3/12, 6/12 3 months, 6 months

 Increase  Decrease

• OK Okay Sx Symptoms
• FOH Family ocular history FMH Family medical history
• GH General health Meds. Medication

LEE Last eye examination LME Last medical examination

Occ. Ointment Gutt. Drops

BID Twice a day TID Three times a day Refer to Appendix V for a comprehensive list of the “Most commonly used Optometric abbreviations” referenced from Berman M and Stelmack T. Ophthalmic clinical abbreviations. Journal of the American Optometric Association 1984; 55:601-604. International Centre for Eyecare Education

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Chapter 3-1(Additional)

Basic Ocular Inspection & Associated Procedures

• This chapter includes a review of:
• Face/head
• Nodes
• Sinuses (frontal & maxillary)
• Orbit/rim
• Adnexae (lids, lashes, conjunctiva, lachrymal apparatus)
• Globe
• Thyroid assessment
• Cornea
• Iris color, pupil and anterior chamber

INTRODUCTION

Gross ocular inspection consists of gross visual assessment, palpation and manipulation of the face, eyes, lids and adnexae to detect any unusual condition or deviation from normal. Although in the course of an eye examination many structures will be assessed specifically and in detail, it is often critical and useful to get a global picture of the patient especially in the area of the head and neck. In other words, it is wise to “look at the whole forest, before looking at each tree”.

Gross observation may be supplemented by some associated procedures to aid not only in the examination and documentation of findings but also in the diagnosis of abnormal conditions. These will be discussed where pertinent under each structure or area under inspection.

FACE / HEAD

Observation

Observation of the face & neck is important in detecting various anomalies that may be related to the patient’s ocular status or total well being. Areas of interest are listed below:

• Facial expressions & symmetry
• Skin color & texture
• Muscular fasciculation or fibrillation
• Hair color & texture
• Gross eye movements & position
• Head position International Centre for Eyecare Education

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• NODES

Palpation

Palpation of the pre-auricular and sub-mandibular nodes for swelling & tenderness can be quite useful in the presentation of some ocular conditions particularly in cases of red eyes. Normal nodes cannot be felt. Swollen and tender nodes typically and most often point towards conjunctivitis or systemic infections by viral organisms. Red eyes secondary to Chlamydial infections can sometimes present with swollen but not tender nodes. Severe allergic reactions & malignant affections can also produce nodal inflammation.

Figure 1

SINUSES (FRONTAL & MAXILLARY)

• Tapping and Trans-illuminating

Tapping & trans-illuminating the sinuses can be helpful in detecting sinus inflammation.

Tapping is performed by gently hitting over the sinus areas using 1 or 2 fingers to detect tenderness or pain.

Trans-illumination is performed in a completely dark room to assess the sinuses for clarity. Tenderness, pain or the presence of dark shadows may indicate the presence of fluids or masses within the sinus cavities.

ORBIT/RIM

Palpation

Palpation of the bony contour looking for irregularities or breaks may give important clues about the status of the orbit & rim especially in cases of trauma. Tenderness, pain, lumps or crepitus (air in soft tissues) may prove to be valuable diagnostic indicators. The practitioner should of course be familiar with the normal aspect of the orbit & rim.

ADNEXAE

(LIDS, LASHES, CONJUNCTIVA, LACHRYMAL APPARATUS)

• Drawn from Catania, 1ary Care of the
• Pre-auricular nodes
• Sub-mandibular International Centre for Eyecare Education

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Observation and Palpation

Observation & palpation of the lids, lashes, conjunctiva, lachrymal apparatus as well as noted abnormalities provide important diagnostic information. The inspection of tissues under natural lighting is probably the easiest & most reliable way to examine the mentioned areas. Natural lighting provides a soft illumination and an undisturbed view that is often necessary to properly assess tissues. Feeling & squeezing abnormalities also yields information about the content and nature of any observed anomaly.

In assessing structures via observation and palpation, it is worthwhile noting findings concerning color, texture, integrity, position, symmetry, elicitation of tenderness or pain, etc.

Functional Assessment

Functional assessment of the adnexae can also be performed by simple visual inspection. The blink quality, completeness & rate or the tear drainage are best studied while the patient is sitting undisturbed.

Lid Eversion

Lid eversion may be warranted while the patient is sitting in the ophthalmic chair and not necessarily behind a biomicroscope. The lid should be everted whenever an anomaly or a foreign body is suspected under the lid. A single or double lid eversion can be performed. A double lid eversion, more properly called lid retraction, is usually reserved when a foreign body is suspected in the superior cul-de-sac.

• Single lid eversion
• Position the patient’s head firmly on the chair’s headrest
• Have the patient look down keeping the eyes opened & relaxed
• Grasp the lashes of the lid between the index & thumb of one hand
• With the other, place the index or a cotton tip gently above the lid crease (tarsus)
• Gently press downward on the lid
• Avoid pulling on the lashes; proper pressure is sufficient to cause the lid to evert
• With the lid everted, examine the conjunctiva using a transilluminator or the spotlight
• Double lid eversion
• Proceed as above but use a Desmarres Lid Retractor
• Place the retractor gently over the tarsus until a single lid eversion is obtained
• Slowly lift the handle of the retractor to elevate the lid a little higher
• One may have to gently hold the everted lid on the retractor while lifting the retractor
• Illuminate & observe the superior cul-de-sac

Note that a double eversion does not actually take place. The lid is simply elevated enough to expose the deep cul-de-sac. Care must be taken not to pull the retractor too far back.

Lid Measurement International Centre for Eyecare Education

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Lid measurement is indicated when ptosis is observed. The three measures shown below must be noted. Since ptotic patients often attempt to raise the falling lid(s) with the Frontalis muscle, it is advisable when indicated to firmly hold down the forehead muscle with the palm while performing the measurement. The comparison between both eyes is instrumental in ptosis assessment. As such, the test set-up must be maintained as constant as possible when measuring each eye.

Lid Aperture (LA)

It is the widest portion of the lid aperture when the eye is in primary position. The LA is taken from the lower lid margin to the upper lid margin

• Figure 2 a

Lid Crease (LC)

It is the widest region between the upper lid margin to the lid crease, which is formed by the insertion of the levator muscle into the lid tarsus.

• Figure 2 b

Levator Function (LF):

It is the measure of distance from the upper lid margin when patient is looking down maximally to the same upper lid margin when patient is looking up maximally.

• Figure 2 c
• GLOBE
• LF
• LC

LAInternational Centre for Eyecare Education

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Finger Tension

Finger Tension provides a very gross assessment of intra-ocular pressure (IOP). Finger tension IOP should be reserved as a last resort where more sophisticated methods are not available or possible (e.g. uncooperative patients, infants, developing countries, etc.).

• Have the patient look down
• Gently press on the globe through the upper lid with the tip of both index fingers
• Compare between the eyes
• Assessment of the globe softness
• The harder the globe, the higher the IOP
• Record as: soft, medium, or hard

Retro-displacement

Retro-displacement is used to assess the presence of globe congestion (resistance), due to space occupying lesion, vascular anomaly, or edema. The method is very similar to finger tension IOP except that a more forceful pressure is applied to the globe in order to push it backward into its socket.

• Have patient close eyes
• Simultaneously push back the globes with your thumbs into orbits.
• Note any asymmetry in globe displacement or bilateral limited displacement (resistance)
• Note patient discomfort

Exophthalmometry

Exophthalmometry is used to look for any forward protrusion (exophthalmos) or backward displacement (enophthalmos) of the eye(s) in the orbit. The measurement is performed by assessing the anterior projection of the cornea relative to the lateral orbital rim.

• Luedde/Ruler exophthalmometer
• Patient looks straight ahead
• Feel bony temporal orbital rim
• Place the notch of the exophthalmometer firmly on it, with the scale facing towards the side.
• Look from the side above the ruler or through the transparent Luedde scale.
• Close one eye to reduce parallax (with the Luedde, align the scales on each side as well)
• Assess and note where the apex of the cornea intersects the mm scale
• Test the other eye
• Example of recording: (OD/OS): 17/19mm

Hertel exophthalmometer

• Loosen the screw of the crossbar & ensure that the numeral scale is on top International Centre for Eyecare Education

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• Have the patient look straight ahead
• Feel bony ridge of lateral orbital rim
• Ask patient to close eyes and slowly bring the exophthalmometer forward
• Place right internal arc on right bony temporal rim, then slowly close the exophthalmometer and place
• internal arc of left arm on left temporal orbital rim
• Tighten the locking screw & note base reading closing 1 eye to eliminate parallax
• Have patient open his eyes and look straight ahead
• Look into the mirrors & measure where the apex of the cornea falls on the mm scale.
• Note result of both eyes
• Take base reading before removing instrument away from patient
• Example of recording: (OD/OS @ base): 17/18 @ 100mm or ଵ଻ିଵ଼
• ଵ଴଴
• Norms for Exophthalmometry
• Difference between both eyes < 3mm
• Whites: 12 to 20mm

Blacks: 12 to 24mm

THYROID ASSESSMENT

The thyroid gland consists of a left and right lobe connected inferiorly by the isthmus, a narrow band of tissue roughly midway between the thyroid cartilage and the suprasternal notch, below the cricoid cartilage. The lobes of the thyroid surround the cartilage of the trachea between the trachea and the sternomastoid muscle.

Procedure

• Inspect the neck looking for the thyroid gland. Note whether it is visible and symmetrical.
• Have the patient tilt the head slightly back to accentuate asymmetry or gland enlargement.
• Look for deviations of the trachea.
• Locate the isthmus by palpating just below the cricoid cartilage
• Have the patient swallow. Feel the gland move freely.
• Evaluate the left and right lobes of the gland
• Use the thumb of one hand to fix the lobe on one side
• With the other hand, locate the other lobe between the trachea and sternocleidomastoid.
• Palpate the other side using the index and middle finger
• Identify the cricoid cartilage and move downward 2-3 tracheal rings palpating for the isthmus.
• Move laterally from the midline while palpating for the lobes of the thyroid.
• Reverse hand position and examine the other lobe. International Centre for Eyecare Education

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Clinical Relevance

A thyroid gland inspection is indicated in cases of systemic and ocular signs and symptoms consistent with Grave’s disease.

The normal gland is often not palpable. If palpable, the normal gland feels fairly flat, with the consistency of muscle and should not be tender, spongy, hard, or nodular. A visibly enlarged thyroid gland is called a goiter.

CORNEA

Direct Assessment

Direct assessment of corneal clarity looking for the presence of scars, foreign bodies, infection or inflammation cornea is often useful and easily performed by simple observation.

Corneal Sensitivity

Corneal sensitivity measurement can be useful in diagnosing pathological conditions and neurological disorders affecting the nerves innervating the cornea. Corneal sensitivity can be assessed grossly using the cotton wisp method or more precisely using the esthesiometer. The qualitative assessment of a difference between the 2 eyes is more useful clinically.

Cotton Wisp Method

• Educate patient about the test and ask him to signal as soon as sensation is felt
• Prepare cotton wisp by pulling and twisting a small thread of the extreme cotton part
• Have patient look up
• Place your hand on the patient cheek
• Point the cotton-tip applicator parallel to the corneal plane
• Move cotton wisp slowly from the side towards the apex of the cornea
• Gently touch the cornea somewhere between the limbus and apex (avoid visual axis)
• Continue touching the cornea with the wisp until the patient signal its sensation
• When sensation occurs ask patient to grade it comparing both eyes
• Observe if patient tears or blinks after the wisp contacts the cornea
• Test the other eye
• Example of recording: OD: 50% of OS corneal sensitivity

Esthesiometer

Esthesiometry is a more precise method that uses a calibrated device. The Cochet-Bonnet esthesiometer, the most popular one, uses a nylon filament to evaluate the sensitivity of the cornea. Used more often in research modalities, it is rarely used in practice for diagnostic testing International Centre for Eyecare Education

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IRIS COLOR, PUPIL & ANTERIOR CHAMBER

Inspection

Inspection of the iris & pupil for irregularities or asymmetry in color, size, position & shape is quickly & often best performed with natural lighting while facing the patient. Anterior chamber clarity can also grossly be assessed via direct observation searching for findings such as blood or inflammation, which would obscure the view of the iris.

Anterior Chamber Depth

Anterior chamber depth can roughly be assessed to determine if the patient is at risk of AC angle closure.

Although more precise methods exist, it may be necessary in some cases (e.g. non-cooperative patients, unavailable material) to do so using a gross estimation method with a penlight known as the shadow test.

Penlight Method (Shadow Test)

• Have patient look straight ahead
• Dim room illumination
• Place penlight temporally parallel to the corneal plane,
• Direct the light towards the nasal limbus
• Determine which % of the nasal iris is illuminated
• Record whether the angle is wide open , moderately narrow, or extremely narrow

Adapted from Eskridge JB, et al., Clinical Procedures in Optometry, Philadelphia, PA: J.B.Lippincott Company, 1991.

Figure 3

• Table 1: Estimation of AC angle & Likeliness of angle closure

Figure Angle Type Nasal Iris

• Illumination
• Angle between
• iris & Cornea
• Angle
• Grading Probability of closure
• A Wide open 100% 45 4 Impossible
• B Open 75% 35 3 Unlikely to Impossible
• C Moderately open 50% 20 2 Possible
• D Extremely Narrow 25% 10 1 Very likely
• Light source
• Grade 4 – Wide open angle
• Grade 2 -Moderately narrow angle
• Grade 3 – Open angle

Grade 1 -Extremely narrow angleInternational Centre for Eyecare Education

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Closed 0% 0 0 100%

Adapted from Eskridge JB, et al., Clinical Procedures in Optometry, Philadelphia, PA: J.B.Lippincott Company, 1991.)International Centre for Eyecare Education Section A – PRELIMINARY EXAMINATION