As is the case in the medical evaluation of any patient, obtaining a history is an important step in the evaluation of the eye. Questions should be directed in much the same fashion as when evaluating non-eye-related patient complaints, albeit with a focus on the chief complaint and its relation to the vision system.

Eye complaints generally fall into three groups: visual disturbance, eye pain, and change in the appearance of the eye. Visual disturbances involve either difficulty seeing what is there (blurred vision, foggy vision, dim vision, wavy vision, blind spots, double vision, or total loss of vision) or seeing things that are not there (flashing lights, shimmering lights, floaters, scintillating scotomata, or formed hallucinations).

Eye pain may be characterized as foreign-body sensation, burning, aching, photophobia, or periorbital pain. Patient-reported changes in the appearance of the eye may include redness of the eye or periocular structures, discharge from the eye, white spots on the eye, unequal pupils, bulging of the eye, droopy or retracted eyelids, and swelling or discoloration of the tissues around the eye.

After establishing the chief complaint, further details surrounding the presenting symptoms should be obtained. The causative factor for an eye complaint may be obvious, as in the case of recent mechanical or chemical injury. When an eye injury is reported, ask when the injury occurred and by what mechanism. Ask if the patient was wearing protective glasses. The clinician should also be aware of patient activities such as grinding or hammering metal objects, mowing the grass, or using a line-trimmer that can produce small high-velocity projectiles. These objects can result in a penetrating eye injury that is easily missed on examination. The resultant retained intraocular
foreign object, if untreated, puts the eye at markedly increased risk for endophthalmitis and profound vision loss.

The quality, duration, severity, location, associated symptoms, and any alleviating or exacerbating factors should be noted. Ask the patient if they have had recent eye surgery or have ever experienced similar symptoms in the past. Sometimes, a patient will give misleading information about causation, reinforcing the importance of a careful organized history. Examples include the contact lens wearer who reports having scratched their eye because they are experiencing foreign-body sensation, when in reality the problem is a bacterial ulcer, or the postoperative cataract patient who reports pain and vision loss after bumping their eye, when the real cause is postoperative endophthalmitis.

Ask the patient about all the medications they use and if they have any allergies to medications. This includes eye drops and homeopathic medications. It is important to note whether any medications have been recently started. Many systemic medications, including antihistamines, anticholinergics, cholinergics, adrenergics, antiepileptics, glucocorticoids, antibiotics, and antirheumatics can result in acute or chronic ocular side effects.

Ask the patient if they have established care with an ophthalmologist or optometrist. Ask if they wear eyeglasses or contact lenses, have been diagnosed with any eye diseases, have had eye surgery, or have a history of significant eye injury.

Obtain a history of the patient’s medical problems and past surgeries. It is common for systemic medical conditions to have secondary eye findings. Examples include diabetes (diabetic retinopathy), hypertension (hypertensive retinopathy), rheumatoid arthritis (dry eye, peripheral ulcerative keratitis), cancer (choroidal metastasis), idiopathic intracranial hypertension (papilledema), and autoimmune disease (uveitis).

Gather the patient’s general family history, but also ask the patient specifically whether any eye diseases are prevalent in their family. Glaucoma, congenital cataract, retinal detachment, and numerous retinal and corneal dystrophies run in families.

The social and occupational history may reveal important information concerning risk of eye injury and exposure to caustic compounds. Tobacco, alcohol, and illicit drug use should also be documented. Intravenous drug abuse can produce endocarditis, with endophthalmitis secondary to septic emboli as the initial clinical manifestation. Crack cocaine use can result in corneal perforation from chronic denervation. Prescribed and illicit opioids are known to produce pupillary abnormalities.

A focused review of systems should always be completed, because it may produce important information that can lead the clinician to the correct diagnosis. For example, many patients with acute angle closure glaucoma complain of headache, nausea, and vomiting in addition to their primary complaints of unilateral eye pain and decreased vision.

A patient’s presenting visual acuity is the most important part of the eye exam diagnostically, prognostically, and medicolegally. Visual acuity should be assessed for each eye individually by having the patient or an assistant cover the eye not being tested. Vision is best assessed using a Snellen chart or a near acuity card. Having the patient wear their own glasses, contacts, or readers for the assessment of visual acuity is preferred. Either the examiner or the patient can hold the near acuity card. If a Snellen chart or near acuity card is not available, the clinician can still assess the patient’s vision by having them read print in a magazine or a book or on a smartphone application. It is important to document how the visual acuity was measured and to adhere to the distance calibration for the eye chart or card used.

If the patient is unable to read any print, the examiner should then assess whether the patient can count fingers and record at what distance they are able to do so. For example, the patient may be able to count fingers held 2 feet from their face, in which case the visual acuity should be recorded as “count fingers (CF) at 2 feet.” If the patient is unable to count fingers, the clinician should note whether the patient can see hand movements, and, if so, the visual acuity should be recorded as “hand movements (HM).” If the patient cannot perceive hand movements with a given eye, the eye should be tested for the ability to perceive light; if they can, visual acuity is recorded as “light perception (LP).” For an eye unable to see any light, record “no light perception (NLP).” The fellow eye should be covered to make sure the unaffected eye is not seeing the test image.

It should be noted that light perception vision can sometimes be determined with a bright light even when a patient is unable or unwilling to open the eye. An aversive maneuver by an uncooperative or noncommunicative patient to avoid a bright light shone on an eye may be good evidence of light perception. Pupillary reaction alone is not adequate evidence of light perception.