Most of the presenting manifestations of eye involvement fall into one of 5 categories: (1) subnormal visual acuity; (2) pain or discomfort, (3) change of appearance of lids, orbit, or eye; (4) diplopia or dizziness; and (5) discharge or increase conjunctival secretion. Some of the important features of each complaint are discussed below.
• Subnormal Visual Acuity
A. Duration: Is visual acuity the same as it has been for most of the patient’s life? Was the change noted recently? Was if found by accidentally covering one eye? Has there been a gradual diminution of acuity over months or years?
B. Difference is Visual Acuity in the 2 Eyes: Is the patient certain that visual acuity was formerly the same in both eyes? Has the patient passed an eye examination as part of a driver’s test or military physical examination? At that time was the visual acuity the same in both eyes?
C. Disturbances of Vision:
1. Distortion of the normal shapes of objects (metamorphopsia) is most often due to astigmatism or macular lesions.
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2. Photophobia is commonly due to corneal inflammation, aphakia, iritis, and ocular albinism. Some drugs may produce increased light sensitivity (e.g.
Chloroquine, acetazolamide).
3. Colour change (chromatopsia), such as yellow, white, or red vision, may be due to chorioretinal lesions or lenticular changes, or may be associated with systemic disturbances (e.g, yellow or white vision in digitalis toxicity).
4. Halos, or rings seen when viewing lights or bright objects, are typically thought of as accompanying glaucoma but are also found with other processes causing corneal edema or infiltration as well as with lens changes.
Incipient cataract is the most common cause of halos.
5. “Spots” before the eyes, seen as dots or filaments which move with the eye, are almost always due to benign vitreous opacities.
6. Visual field defects may be due to disorders of the cornea, media, retina, optic nerve, or brain. Quivering or scintillating blind spots (scotomas) may occur transiently as a result of localized constriction of cerebral or retinal arteries.
7. Night blindness, or difficulty seeing in the dark (nyctalopia), may be congenital (retinitis pigmentosa, hereditary optic atrophy) or acquired (vitamin A deficiency, glaucoma, optic atrophy, cataract, retinal degeneration).
8. Momentary loss of vision (amaurosis fugax) may imply impending cerebrovascular accident, spasm of the central retinal artery, or partial occlusion of the internal carotid artery.
• Pain or Discomfort
The usual painful symptoms mentioned are headache, “eye-ach,” and burning or Itching of the eyes or eyelids. Photophobia (sensitivity to light) may cause great discomfort; fatigue symptoms such as “pull,” “tired eyes.” And “a feeling of
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pressure” may be described. Acute localized pain intensified by movement of the eye or lid suggests a foreign body or corneal abrasion.
Aside from poor visual acuity, headache is the most common complaint that causes a patient to go to an ophthalmologist for an eye examination. If the eye examination discloses no pathologic abnormalities that may account for the symptom, a careful description of the type of headache and a history of its onset, relationship to use of the eyes, duration, and associated symptoms may not only rule out eye disease as a probable cause but may indicate the proper diagnosis.
For example, the headache that occurs upon arising in the morning and disappears soon afterward is seldom caused by eye disorders; a general medical examination is indicated. On the other hand, mild to moderate headaches that occur toward the end of a day of exacting eye work and that are relieved by a few hours of rest or sleep are more probably due to ocular disorders. Any case of severe headache that is becoming worse should suggest an intracranial lesion; visual field test, ophthalmoscopy, and neurologic consultation are indicated.
“Eye-ache” often accompanies extreme fatigue with or without excessive use of the eyes. It is more common in patients with muscle imbalances, but it may be present with inflammatory lesions involving the episclera, iris, or choroid. The eyes may also ache with the increased pressure of glaucoma. In severe acute congestive glaucoma, the pain may be so intense as to radiate throughout the cranium and be accompanied by nausea and vomiting. Ocular pain may also be caused by fever, neuralgia, retro bulbar neuritis, and temporal arthritis. Aching eyes constitute one of the first symptoms of severe influenza and dengue. Burning and itching may be a symptom of eyestrain, but the most frequent cause is inflammation of the lids or conjunctiva, e.g., chronic blepharitis, conjunctivitis,
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and allergic reactions of the hay fever type. Itching in particular, is a symptom of ocular allergy.
A sensation of “pull” is often described in adjusting to a new lens prescription, particularly if the prescription incorporates a change in astigmatic correction.
There may also be sensations of pull or actual ache in adjusting to the first pair of bifocals.
• Change in Appearance
A. Discoloration: Redness or congestion of the lids, conjunctiva, or sclera may