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Orthoptic abbreviations

Eesophoria

Hhyperphoria

Clinical skills

Obtaining an ophthalmic history 2 Assessment of vision: acuity (1) 5 Assessment of vision: acuity (2) 7

Assessment of vision: clinical tests in children and tests of binocular status 9

Assessment of vision: contrast and color 11 Biomicroscopy: slit-lamp overview 13 Biomicroscopy: use of the slit lamp 15 Anterior segment examination (1) 17

Additional techniques for anterior segment examination 18 Anterior segment examination (2) 19

Gonioscopy 20

Posterior segment examination (1) 22 Posterior segment examination (2) 24 Pupillary examination 27

Ocular motility examination (1) 29 Ocular motility examination (2) 31 Visual fields examination 33 Lids/ptosis examination 34

Orbital examination 36 Nasolacrimal system examination 38 Refraction: outline 40

Refraction: practical hints 42 Focimetry 44

2CHAPTER 1 Clinical skills

Obtaining an ophthalmic history

One of the first and most vital skills acquired by those involved in eye care is the accurate and efficient taking of an ophthalmic history. In ophthalmology clinical examination is very rewarding, probably more so than in any other specialty. However, this is additional to, rather than instead of, the history.

Apart from the information gained, a rapport is established which should help the patients to tolerate the relatively invasive ophthalmic examination. The patients are also more likely to accept any subsequent explanation of diagnosis and ongoing management if they know they have been listened to.

Presenting illness (PI)

Why are they here?

The patient’s initial illness (i.e., complaint) often helps to direct additional questioning and examination. Routine eye care referral has a valuable role in screening for asymptomatic disease (notably glaucoma) but may generate unnecessary referrals for benign variants (e.g., anomalous discs, early lens opacities).

History of presenting illness (HPI)

The analysis of most ophthalmic problems center around general questions regarding the onset, precipitants, associated features (e.g., pain, redness, discharge, photophobia, etc.), duration, relieving factors, recovery, and specific questions of the presenting illness (i.e., complaints) (Box 1.1). Even after clinical examination, further information may be needed to include or rule out diagnoses.

Although some of these processes can be formalized as algorithms, their limitations should be recognized; they cannot compare to the multivariate processing, recognition of exceptions, and calculation of diagnostic probabilities subconsciously practiced by an experienced clinician.

Past ophthalmic history (POH)

The background for each presentation is important. Inquire about previous surgery/trauma, previous/concurrent eye disease, and refractive error. The differential diagnosis of an acute red eye will be affected by knowing that the patient had complicated cataract surgery 2 days previously or has a 10-year history of recurrent acute anterior uveitis, or even that the patient wears contact lenses.

Past medical history (PMH)

Similarly, consider the entire patient. Ask generally about any medical problems. In addition, inquire specifically about relevant conditions that they may have forgotten to mention. The patients presenting with recurrently itchy eyes may not mention that they have eczema or asthma. Similarly, if they have presented with a vascular event, ask specifically about diabetes, hypertension, and hypercholesterolemia.

OBTAINING AN OPHTHALMIC HISTORY 3

Box 1.1 Obtaining the history of the presenting illness (HPI)—an example

Patient presenting with loss of vision

Did the event occur suddenly or gradually?

Sudden loss of vision is commonly associated with a vascular occlusion (e.g., AION, CRAO, CRVO) or bleeding (e.g., vitreous hemorrhage, “wet” macular degeneration). Gradual loss of vision is commonly associated with degenerations or depositions (e.g., cataract, macular dystrophies or “dry” macular degeneration, corneal dystrophies).

Is the vision loss associated with pain?

Painful blurring of vision is most commonly associated with anterior ocular processes (e.g., keratitis, anterior uveitis), although orbital disease, optic neuritis, and giant cell arteritis may also cause painful loss of vision.

Is the problem transient or persistent?

Transient loss of vision is commonly due to temporary/subcritical vascular insufficiency (e.g., giant cell arteritis, amaurosis fugax, vertebrobasilar artery insufficiency), whereas persistent loss of vision suggests structural or irreversible damage (e.g., vitreous hemorrhage, macular degeneration).

Does the problem affect one or both eyes?

Unilateral disease may suggest a local (or ipsilateral) cause. Bilateral disease may suggest a more widespread or systemic process.

Is the vision blurred, dimmed or distorted?

Blurring or dimming of vision may be due to pathology anywhere in the visual pathway from cornea to cortex; common problems include refractive error, cataract, and macular disease. Distortion is commonly associated with macular pathology, but again may arise from high refractive error (high ametropia/astigmatism) or other ocular disease.

Where is the problem with their vision?

A superior or inferior hemispheric field loss suggests a corresponding inferior or superior vascular event involving the retina (e.g., retinal vein occlusion) or optic disc (e.g., segmental AION). Peripheral field loss may indicate retinal detachment (usually rapidly evolving from far periphery), optic nerve disease, chiasmal compression (typically bitemporal loss), or cortical pathology (homonymous hemianopic defects). Central blurring of vision suggests diseases of the macula (positive scotoma: a “seen” spot) or optic nerve (negative scotoma: an unseen defect).

When is there a problem?

For example, glare from headlights or bright sunlight is commonly due to posterior subcapsular lens opacities.

4CHAPTER 1 Clinical skills

Family history (FH)

This is relevant both to diseases with a significant genetic component (e.g., retinitis pigmentosa, some corneal dystrophies) and to infectious conditions (e.g., conjunctivitis, TB, etc.).

Social history (SH)

Ask about smoking and alcohol intake if relevant to the ophthalmic disease (e.g., vascular event or unexplained optic neuropathy, respectively). Consider the social context of the patients. Will they be able to manage hourly drops? Can they even take the top off the bottle?

Drugs and allergies

Ask about concurrent medication and any allergies to previous medications (e.g., drops), since these may limit your therapeutic options. In addition to actual allergies, consider contraindications (e.g., asthma or chronic obstructive pulmonary disease [COPD] and B-blockers).