FOURTH IN A SERIES

PHYSICAL ASSESSMENT OF THE OCULAR APPARATUS

by David E. Stewart, Quentin M. Srnka, Jon C. Calvert and R. Leon Longe

Introduction INTRAOCULAR (WITHIN THE EYE) DISEASE and many disease states affecting other body systems can be detected through physical assessment of the ocular apparatus. Also, the severity of various chronic diseases can be determined and the progress of certain disease states can be followed. Important to the pharmacist and the physician is the fact that use or misuse of certain medications may produce characteristic changes in the

DAVID E. STEWART, Pharm.D., is Pharmacy Resident, and QUENTIN M. SRNKA, Pharm.D., is Associate Professor of Pharmacy Practice, College of Pharmacy, University of Tennessee Center for the Health Sciences, Memphis, Tennessee. JON C. CALVERT, M.D., Ph.D., is Professor and Chairman, Department of Family Practice, Medical College of Georgia, Augusta, Georgia and R. LEON LONCE, Pharm.D., is Assistant Professor of Pharmacy, School of Pharmacy, University of Georgia, Athens, Georgia.

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functions and/or appearance of the anatomical structures of the eye. The eye is unique, in that better than any other organ or organ system it serves as a "window" through which, by noninvasive means, the microcirculation can be visualized. Inspection of the vasculature is useful in assessing the severity öf several common diseases. Hypertension, for example, yields characteristic changes in veins and arteries and may result in hemorrhages and exudates of the fundus (retina). These abnormalities are often visible upon inspection with the ophthalmoscope. Because the retina and associated structures are an extension of the brain, examination of the retina may reveal the presence of certain diseases involving the brain.

Anatomy and Physiology To appropriately consider the physical assessment of the ocular apparatus, it is essential to understand the

basic anatomy and function of gross ocular structures. With the exception of the cornea, the portions of the eyeball visible upon inspection (Figure 1) are covered by the conjunctiva. The conjunctiva merges with the cornea at the limbus (junction of the sciera and cornea). The conjunctiva folds above and below to form the inner tissue (mucosa) of the eyelids. The small vessels of the bulbar conjunctiva are numerous and are apparent upon inspection with the unaided eye. The eyeball itself is composed of three concentric layers of tissue which encase the inner fluids of the eye (Figure 2). The outer layer of the sphere (globe) of the eye is called the sciera. Anteriorly, the normally opaque sciera is clear or transparent and is called the cornea. Behind the lens and immediately adjacent to the aqueous humor is a nerve tissue called the retina. The retina contains the nerve endings, rods and cones that function as visual sensory receptors. Between the innermost layer, the retina, and the outermost layer, the sciera, is a layer called the choroid. The choroid layer contains the blood vessels, arteries and veins and a black pigment layer which reflects light images back onto the sensory receptor rods and cones in the retina. The fluids within the eyeball are divided by the lens into two chambers. The anterior chamber (that portion of the inner eye between the cornea and the lens) contains the fluid termed aqueous humor. The lens is suspended in this fluid. The posterior portion of the inner eye between the lens and the retina contains the vitreous humor. The anterior portion of the eye, anterior to the lens, contains the ciliary body and the iris. The ciliary body contains muscle tissue. The doughnut shaped ciliary body is connected by ligaments to the lens: the lens sits in the hole of the doughnut. Contraction or relaxation of the ciliary body places tension on the lens and causes it to change shape, and thus accommodate to far and near vision. The iris is a pigmented structure (blue eyes, brown eyes, etc.) containing muscle fibers. It is located anterior to die ciliary body and posterior to the cornea. Contraction and relaxation of the muscle fibers causes the lens to open or close, much in the way the diaphragm of a camera opens or closes to control the amount of light that reaches the film (retina). The innermost layer of the eyeball, the retina, is an externalized portion of brain. The optic nerve, connecting the retina to the brain, is structurally and functionally a nerve tract of the central nervous system (brain and spinal cord) rather than a peripheral nerve. There are two groups of muscles found in the ocular apparatus. The intrinsic muscles are located within the eye and are involuntary and controlled by autonomie nerves. These intrinsic muscles have been described previously as the muscles of the iris and the ciliary body. The involuntary muscle of the iris controls the size of the pupil and the involuntary muscles of the ciliary body control the shape of the lens. A second group of muscles, the extrinsic muscles, are attached to the sciera, the outer layer of the globe and to the bones and cartilage Drug Intelligence and Clinical Pharmacy

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TERMINOLOGY

TONOMETRY - the measurement of pressure or tension within the eye. OPHTHALMOSCOPY - examination and visualization of the fundus (retina), cornea and lens of the eye by means of the ophthalmoscope. FUNDUSCOPIC EXAM - relating to the visualization of the eye fundus (retina) with the ophthalmoscope. ( Synonymous- with retinal exam or exam of the "eye grounds".) VISUAL ACUITY - relating to the ability of the eye to focus on both near and far objects. OCULAR APPARATUS - consists of the eyeball and its parts, the extraocular muscles responsible for eye movement as well as the nerves, arteries and veins going to and from the eyes. PTOSIS - drooping of the upper eyelid. EXOPHTHALMOS - protrusion of the eye. DIPLOPIA - perception of two images of a single object. MYOPIA - near sightedness. HYPEROPIA - far-sightedness. STRABISMUS - an eye muscular defect resulting in one eye turning inward or outward. NYSTAGMUS - involuntary rapid movement of the eyeball, which may be horizontal, vertical, rotatory or mixed.

ABSTRACT

The article introduces the physical assessment of the ocular apparatus. Normal and abnormal anatomy and physiology are described, along with assessment techniques and tools. Drugs affecting the eye are discussed and a case study is presented. APR 78

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Competency Statement on the Physical Assessment of the Ocular Apparatus STATEMENT ON ANATOMY AND PHYSIOLOGY

Given a case presentation, the reader should be able to correctly respond to questions on the basic anatomy and physiology of the ocular apparatus.

Elaboration The reader should know the gross anatomical structures of the eye and the basic physiologic actions of the eye. STATEMENT ON METHODS OF ASSESSMENT AND CLINICAL FINDINGS

Given a drug history and physical examination of the eye, the reader should be able to (1) recognize normal/abnormal physical and historical information and (2) answer questions concerning methods of performing physical assessment of the eye. Elaboration The reader should know (1) methods of assessing the eye, (2) normal physical findings of the eye and some common abnormal physical findings. The reader should know how to use the Snellen Chart, flashlight, tonometer and ophthalmoscope, as related to methods of physical assessment of the eye. The reader should know the physiological basis of normal and abnormal clinical findings. The reader should know historical content suggesting the presence of or potential for, eye disease. STATEMENT ON MONITORING DRUG THERAPY ON THE EYE

Given a case study, the reader should be able to evaluate drug action on the ocular apparatus.

Elaboration The reader should be able to write baseline normal physical findings. The reader should be able to recognize patients requiring pharmacotherapeutic evaluation. The reader should be able to recognize medicinal agents potentially harmful to the eye. STATEMENT ON MEDICAL TERMINOLOGY

Given medical terms, the reader should be able to communicate them. Elaboration The reader should be able to define medical terms relating to the eye. The reader should be able to communicate (both in writing and verbally) medical terms in a manner consistent with the health provider's/patient's level of understanding.

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of the orbit (eye socket). There are six extrinsic muscles, each composed of voluntary muscle fibers innervated by motor and sensory non-automatic nerves. These six extrinsic muscles can move the eyeball in virtually any direction. When the eye is viewed through the cornea, pupil and lens using an ophthalmoscope, the fundus (retina) is visualized. The fundus (Figure 3) contains the optic disc, macula, fovea, arteries and veins. Inspecting the fundus is termed funduscopic exam. The optic disc is that part of the retina through which the nerves, arteries and veins enter from behind the globe. The macula and fovea are the most sensitive parts of the retina. This is where the light rays passing through the cornea and lens are maximally focused. The funduscopic examination is an important and valuable adjunct to the determination of ocular status and in the evaluation of the severity and progress of certain disease states. There are many specialized references dealing with eye disease that contain textbook descriptions and color photographs of fundi reflecting the various disease states.

Physiohgy of Vision There are four processes which focus light rays so that a clear image may be formed on the retina: (1) refraction of light, (2) accommodation of lens, (3) constriction of pupil, and (4) convergence of eyes. Refraction of light means the bending or deflecting of light rays as they pass through the cornea, aqueous humor, lens and vitreous humor, so that these rays focus on the retina in the area of the fovea. When these light rays are not clearly focused on the retina, corrective lenses may be necessary to alter the refraction of light so that a clear image is formed on the retina. Accommodation of the lens involves a change in its curvature. The lens may be stretched or relaxed and in this manner assists in the focusing of an image on the retina. Correct accommodation of the lens must occur so as to allow visualization of objects at both near and far distances. With age, the lens loses some of its elasticity that aids in near vision. Bifocal lenses are then prescribed. These assist the wearer to again clearly focus images on the retina. Constriction of the pupil occurs secondary to movements of the iris and in response to attempts to visualize near objects or to protect the retina from strong bright light by preventing too intense or too sudden stimulation of the retina sensory receptors. Constriction of the pupils also prevents blurred images that would otherwise be produced through peripheral light rays entering the pupil. Convergence of the eyes is the movement of the eyeballs inwards so as to allow binocular vision of near objects. The nearer the object, the more convergence must occur for a clear image to be cast on the retina. Normal vision occurs when light rays pass through the cornea, aqueous humor, pupil, lens and vitreous humor and are then focused upon the retina. The image produced on retinal receptors (cones and rods) produces neural impulses which are conducted to the visual areas

PHYSICAL ASSESSMENT OF THE EYE

Upper Eyelid Lateral Canthus

Medial Canthus Sciera Covered by Conjunctiva

Lower Eyelid

Limbus (junction of cornea and sciera)

Figure 1. The ocular apparatus visible upon Inspection

(cortex) of the brain. Disease of the cornea, pupils, lens, anterior chamber (aqueous humor), posterior chamber (vitreous humor), retina, optic nerve, or visual cortex which prevents the passage of light rays to the retina or the transmission of nerve impulses from the retina to the cortex, or reception of the impulses by the cortex may result in decreased visual acuity or blindness. An important part of the ocular apparatus is the area of the external eye which includes the eyelids and the lacrimal duct, which drains the fluid secreted by the lacrimal gland. The lacrimal gland secretions continually bathe the sciera and cornea and maintain its integrity. The lacrimal duct carries these secretions from the eye to the nasal cavity. Also, there are various glands associated with the hairs of the eyelids, as well as the parafollicular glands of the eyelid that may be

involved in disease processes. It is also important to realize that the conjunctiva of the eyelids is a mucus membrane which may also reflect disease processes, such as anemia and allergies.

Physical Assessment of Ocular Apparatus As described in the introductory article of this series, there are four basic techniques of physical assessment: (1) inspection, (2) palpation, (3) percussion, and (4) auscultation.1 Of these four techniques, inspection and limited palpation are most useful in the assessment of ocular status. Also of value is the application of other methods for the determination of intraocular tension and visual acuity. If the reader is unfamiliar with these four basic techniques, a review of the introductory article is suggested.

Figure 2. Horizontal cross section of the eye

Rectus Muscle Sciera

Conjunctiva Ciliary Body Post. Chamber Cornea Pupil Ant. Chamber Iris Zonule

Choroid Retina Vitreous Chamber Fovea Optic Nerve

Ciliary Muscle

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Visual acuity is defined as the ability to distinguish form and outline by a fraction that compares the distance at which an individual sees an object clearly with the distance at which the normal eye would see the object. To test visual acuity, the traditional Snellen Chart is utilized.2 The usual distance from the chart to the eye is arbitrarily set at 20 feet. At this distance, letters of a specific size can be identified by the normal eye. The line of letters is labeled 20 feet. If the normal subject stands at 100 feet, another row of letters which are identifiable would be labeled 100 feet. If a myopic (nearsighted) person is now standing at 10 feet, he may possibly be able to read only the line marked 20. He will then be said to possess a visual acuity of 10/20. Normal vision is, of course, 20/20. Any drug that can interfere with accommodation (affect the smooth muscle of the iris or ciliary body) may alter visual acuity. Parasympathomimetics and anticholinergics may change the shape of the lens or the ability of the lens to constrict and alter focusing. Eyelids (both external skin and internal mucus membranes ) are visualized and may also be palpated to detect masses or irregularities. Periorbital edema (swelling of the subcutaneous tissue of the eyelid) is determined by palpation and inspection. Lids are observed for ptosis (drooping of upper lids), retardation (failure of lids to cover eyeball) and abnormal growths. Abnormal movement of the lids may suggest various pathological states. While examining the eyelids, the relationship of the eyeball (globe) to the eye socket (bony orbit of the eye) should be considered. In some patients having a hyperactive thyroid gland, the eyeball (globe) may be pushed outward in the socket and appear to be bulging from the socket. This is termed exophthalmos or proptosis. As discussed, the conjunctiva covers the inside of the lids and folds to cover the sciera up to the cornea. There are numerous vessels in the conjunctiva and these are subject to irritation by allergens, viral or bacterial infection and foreign bodies. Inspection may reveal the presence of conjunctivitis, a condition in which the conjunctiva becomes red secondary to the dilatation of scierai blood vessels in response to the irritating agent. Parts of the conjunctiva may be inspected by merely observing the eye. To visualize the conjunctiva beneath the lower lid, it must be pulled from the eye very gently. Visualization of the conjunctiva of the upper lid, however, requires eversion of the lid. Generally the examiner places a tongue depressor, Q-tip applicator, or the eraser tip of a pencil about 1 cm above the upper lid margin and then everts the lid by turning up the upper lash and lid. This is not a simple procedure and must be done with care in order not to injure parts of the ocular apparatus. The presence or absence of growth, inflammation, or a foreign body is then observed. A perfectly smooth and perfectly clear cornea is essential for good vision. Light directed in an oblique 218

manner upon the cornea will help detect abrasions and/or opacities, two of the most common abnormalities. The instillation of fluorescein onto the conjunctiva and sciera by the use of a fluorescein strip will aid in the elucidation of abrasions, which will be characterized by a brilliant yellow-green color under proper lighting conditions. The fluorescein differentially attaches to the damaged epithelium of the cornea and sciera. The cornea is normally devoid of vascularization and depends upon surrounding tissues for oxygen and nutrition. The presence of vessels usually indicates the presence of a pathologic (abnormal) process. Because the cornea is normally clear, its inspection is facilitated by the use of the ophthalmoscope. Normal pupils are round, of equal size and will react by constricting bilaterally, equally and consensually to light. This is accomplished when light from a flashlight is directed to the retina of one eye or the other in a darkened room. When light is directed through the cornea to the retina of one eye, both pupils will constrict simultaneously and to an equal degree. The procedure is repeated with the other eye. A lesion (neurological or otherwise) is suggested if bilateral equal and consensual constriction does not occur. As a normal variation, pupils may be of unequal size. This may be harmless but it should not be dismissed as a variant of normal without examination by a physician. The intraocular tension or pressure exerted on the eyeball by fluid from within can be measured through tonometry. A tonometer is placed upon the cornea of the anesthetized eye and a reading obtained. This reading is converted from a table to mm Hg. Glaucoma is a condition characterized by high intraocular pressure (tension) and may be diagnosed through the use of tonometry. It may have no other accompanying symptoms or signs. The increased intravascular pressure of glaucoma produces characteristic changes in the optic disc which may be visible upon inspection with an ophthalmoscope. A well known harmful potential of anticholinergic agents is to increase the pressure within the glaucomatous eye. Other agents, such as pilocarpine (a parasympathomimetic), may reduce the intraocular tension of glaucoma. Each eye's movement is controlled by the action of six voluntary muscles. The third, fourth and sixth cranial nerves innervate these muscles. A problem or lesion of any one nerve would result in abnormal extraocular movement of the eyeball. To test whether or not the eyes' extraocular muscles and/or nerves are intact (functioning normally), the patient is instructed to direct eye movement in each of six cardinal directions. The inability of either one or both eyes to move appropriately indicates a potential muscular and/or nerve problem. Nystagmus is a rhythmic oscillation of the eyes. There are various types of nystagmus, with classification depending upon the direction of movement. Phenytoin, for example, can produce nystagmus, as can several pathological states. An important and informative portion of the assessment of the eye is the ophthalmoscopic evaluation of

PHYSICAL ASSESSMENT OF THE EYE

Figure 3. The fundus, showing its landmarks

the fundus or the posterior portion of the ocular apparatus. Use of the ophthalmoscope allows access to the anterior and posterior compartments of the eye. The anterior ophthalmoscope permits the examiner to visualize the cornea, anterior chamber, lens, posterior chamber and the retina, its vasculature and its anatomical landmarks. Besides the detection of ocular abnormalities, a thorough examination can sometimes detect more serious systemic diseases involving, for example, the cardiovascular system (hypertension, atherosclerosis) and diabetes mellitus. A successful ophthalmoscopic examination requires cooperation from the patient and a darkened room. Dilatation of the pupil by some mydriatic agent, such as tropicamide 1 percent, or phenylephrine 10 percent is sometimes beneficial and allows for visualization of a larger portion of the retina. There are several types of ophthalmoscopes available, with various apertures and colored filters. For most examinations, the small round white light is most suitable. It must be stressed that becoming skillful and confident in performing the ophthalmoscopic exam requires a considerable amount of experience. There is a wide range of normal variants that should not be confused with a wide variety of obvious and not so obvious pathological findings. In examining the fundus of the normal eye, the most conspicuous feature is the optic disc (Figure 3). If the optic disc is not immediately seen, a major vessel may be traced proximally until its point of origin from the optic disc is visualized. When examining the optic disc, the size, shape, color and margins should be particularly noted. Major changes in the optic disc that may be distinguished include optic atrophy (death of optic nerve fibers), papilledema (swelling of the optic disc margin with loss of sharp demarcation between optic disc and retina) and changes in the optic disc referred to as "cupping" which is characteristic of glaucoma.3 Drug Intelligence and Clinical Pharmacy

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Changes characteristic of glaucoma within the disc are due to the increase in intraocular pressure. The disc will take on an abnormal curvature and backward displacement because of the increased pressure. If increased pressure is prolonged,. it leads to the death of optic nerve fibers. Of importance in the ophthalmoscopic examination is the observation of arteries and veins in the retina. Close observation of the retinal vessels may detect such diseases as hypertension, diabetic changes, anemias and blood dyscrasias, as well as inflammatory and toxic processes. Changes in disease states are often evaluated by serial assessment of the integrity of the retinal vessels over long periods of time. The Keith-Wagner system of classification of vasculature and retinal changes is useful in assessing the severity of the effect of hypertension on the peripheral vascular systems. The changes noted in the retina appear to be one of the most accurate guides to the prognosis of hypertension.4 Retinal changes by the Keith-Wagner system of classification are as follows: Grade 1 Changes: Minimal arteriolar narrowing Grade 2 Changes: Arteriovenous "nicking" plus Grade 1 changes Grade 3 Changes: Hemorrhage and exudate plus Grade 2 changes Grade 4 Changes: Papilledema plus Grade 3 changes5 Diabetic changes in the vasculature of the retina is one of the most common causes of visual loss in patients under 65 years of age. As many as 75 percent of patients who have had diabetes for ten years or more have some degree of retinopathy.8 Diabetic retinopathy ranges in severity from edema and hemorrhages to areas of new vascularization and proliferating fibrous tissue which may cause detachment of the retina. Arteries are usually easily differentiated from veins in that arteries are 25 percent smaller in diameter, APR 78

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Table 2. Drugs Capable of Producing Adverse Ocular Effects* Conjunctival Congestion Carbachol Epinephrine Miotics Conjunctival Pigmentation Epinephrine Conjunctivitis Carbamazepam Noscapine Physostigmine Cataracts Corticosteroids Anticholinesterase Agents (Long Acting) Busulfan Corneal Damage Indomethacin Cocaine Chloroquin Chlorpromazine Corticosteroids

Nystagmus Carbamazepine. Cephaloridüie Phenytoin Lithium carbonate Methocarbamol Oculogyric Crisis Antipsychotic Agents Photophobia Anticholinergic Agents Quinine Quinidine Retinopathies Chloroquin Indomethacin Miotics Chlorpromazine Thioridazine Oral Contraceptives Uveitis Anticholinergic Agents

Optic Nerve Damage Chloramphenicol Disulfiram Ethambutol Isoniazid Increased Intraocular Tension Oral Contraceptives Adrenergic Agents Chloroquin Anticholinergic Agents Streptomycin Antipsychotics Topical Corticosteroids Quaternary Ammonium Compounds Opacities and Pigmentation Corticosteroids of Lens Mydriasis Chlorpromazine Thiothixene Amphetamines Anticholinergic Agents Miosis Levodopa Narcotic Analgesics Quinine Anticholinesterase Quinidine Agents Tricyclic Antidepressants Eye Lid Edema Idoxuridine Iodine

♦Derived from AMA Drug Evaluations, 2nd Ed., Publishing Sciences Group, Acton, Mass., 1973.

brighter red in color and manifest an arteriolar light reflex. The arteriolar light reflex is a narrow band of bright light reflected from the center of the artery. In the normal retina, arteries and veins often cross in a random manner. Arteriovenous crossing should be noted and evaluated for the presence of abnormal venous indentations (nicking) which are characteristic of atherosclerosis, as well as hypertension. As opposed to arteries, veins are slightly larger and darker and they do not have the prominent light reflex. A slight, visible pulsation can usually be noted at the proximal end of the vein where it overlies the optic disc margin. This is termed venous pulsation and is normal. The macula is an area on the retina located lateral (temporal) to the optic disc. If the macula is difficult to visualize, it may be helpful to instruct the patient to look directly into the ophthalmoscope. This will place 220

the macula in the center of the examiner's visual field. The macula deserves special attention since it is the region of the retina with the greatest visual acuity. The miniature spot of reflected light seen in the center of the macula represents a small fine depression, the fovea (Figure 3 ) . Table 1 summarizes the normal physical findings of the eye.

Monitoring Drug Action on the Eye Many drugs affect the eye, both directly and indirectly. Topical agents such as anticholinergics (e.g., atropine) act directly on the eye, whereas systemic antiobiotics control certain infections of the eye. As with any drug, ophthalmologic agents may cure or cripple. The clinical pharmacist, in cooperation with the physician, must be alert to the dramatic or insidious dynamics of therapeutics. Table 2 presents some drugs reported to be toxic to the eye. Some of these agents are prescribed for ophthalmologic disease, while others ameliorate other conditions. Patients receiving any of these agents should have a periodic eye examination. Any patient reporting, via drug history, the previous administration of any of these agents should be assessed. Or, when initiating chronic, high dose treatment with any of these drugs, a baseline recording should be made, such as: eyes: lashes and brows intact. No exaphthalmos or ptosis. Conjunctivae clear. Sclerae white. No corneal defects. Snellen 20/20 both eyes. Extraocular movements (EOM) intact. No strabismus or nystagmus. Color vision normal. Pupils are equal, round, react to light and accommodation (PERRLA). Discs clear. No A-V nicking, hemorrhages or exudates. Tonometry normal. Blurring of vision or ocular pain requires careful examination by a competent clinician. Reddened eyes are sometimes secondary to an allergy to an eye cosmetic. Patients with narrow, closed angle glaucoma should be advised to avoid self-medication with anticholinergic or adrenergic agents which may precipitate a glaucomatous attack. Open-angle glaucoma is not a contraindication to their use. However, unless the pharmacist has consulted with the physician (i.e., desirably an ophthalmologist), the patient should avoid glaucomainducing agents. Convenient use of a topical corticosteroid carries the dangers of suprainfection (especially by virus or fungus) and drug-induced tissue damage.

Conclusion Assessment of the ocular apparatus demands that the examiner be experienced and competent in order that even obvious changes be detected. The eye truly serves a dual purpose. It not only allows the patient to visualize that which occurs around him, but it also provides a "window" through which certain normal internal body processes may be visualized and assessed. A competency test will be forthcoming for self-evaluation.

PHYSICAL ASSESSMENT OF THE EYE Table 1. Normal Physical Examination of the Ocular Apparatus

Appendix

Vision

CASE STUDY AND DISCUSSION Patient Profile: A 52-year-old white male having essential hypertension and peptic ulcer disease had been treated by his family physician with the following: Methyldopa

500 mg bid

Hydrochlorothiazide Glycopyrrolate

Orbits Lids

100 mg qd

2 mg qid

Potassium (Wax Matrix)

Conjunctiva

16 mEq qd

Magnesium/Aluminum Hydroxide Suspension prn On 4-1-77 the patient appeared at his local pharmacy requesting medication for the relief of headache. The patient, realizing that he should not take aspirin, asked the assistance of the pharmacist in the selection of a remedy. The pharmacist interviewed the patient concerning the character, location, duration and intensity of the pain. The patient reported a sharp pain, not unlike that of toothache. Pain had persisted for six weeks but, during that period, would increase and decrease in intensity during the day. Pain occurred primarily "behind" the eyes and was of increasing intensity during the last two weeks. Upon review of the patient's medication profile, the pharmacist suggested immediate referral to the family physician. The following data was obtained in the clinician's office.

Sciera Cornea Pupils Movement

Lens Anterior Chamber Fields Pressure

Subjective: Occasional blurred vision; pain in and behind both eyes but primarily right eye affected; occasional nausea and vomiting; has noticed reddening of eyes during last two weeks.

Uveal Tract

Objective: Pupils dilated bilaterally; decreased visual acuity in both eyes from previous exam; applanation tonometry yielded a right eye pressure of 60 mm Hg and a left eye pressure of 32 mm Hg.

Disc

Retina

Arteries

Acuity in normal range (20/20 by Snellen Chart is perfect) Color perception appropriate Depth perception appropriate Size, position and prominence in normal range Sphere of eye covered when lids closed Upper lid follows iris in downward movements No periorbital edema No external inflammation, growths, structural abnormalities Clear on sciera without redness Conjunctiva of lids pink without excessive redness No growths or structural abnormalities White, with a possible bluish cast Transparent without abrasions Bilaterally round, symmetrical, equal in size Pupils equally reactive to light and accommodation Spheres move in coordinated manner in six cardinal directions Spheres devoid of motion when gaze is fixed No deviation or nystagmus Transparent Depth appropriate Contents clear Normal central and peripheral vision Blind spot appropriate Intraocular pressure in normal range (usually 21 mm Hg or less) Iris, choroid, ciliary body appropriate and intact Reddish-orange color (differs with race) intact Pink color (differs with race) Round to vertically ovoid Sharp borders Appropriate site of vascular insertion Normal artery/vein size ratio (2:3) Light reflex present and of appropriate color No a/v nicking No tortuosity, hemorrhages, exudates, or papilledema Appropriate size No tortuosity, hemorrhages, exudates, or papilledema

Assessment: Acute closed angle glaucoma (further recognized through gonioscopy) aggravated by the use of an oral anticholinergic agent (glycopyrrolate).

Veins

Plan: Discontinue the use of the anticholinergic agent (glycopyrrolate); admit to ophthamology service for acute care and surgical work-up. The patient was given 75 mg of meperidine hydrochloride for relief of pain. Four ounces of glycerol over ice with lemon juice was administered orally, in order to reduce the intraocular pressure. Pilocarpine 4 percent was started at the rate of 2 drops to each eye every 15 minutes for 4 hours. The following day the patient received a peripheral iridectomy in surgery. Angle closure glaucoma occurs when there is a sudden increase in intraocular pressure due to a blocking of the outflow of aqueous humor from the anterior chamber secondary to closure of the angle by the iris. This patient's acute attack was aggravated by use of the anticholinergic agent glycopyrrolate, which produced pupillary dilatation (mydriasis) and a subsequent blocking of the angle of the anterior chamber.

1. Longe, R. L. and Calvert, J. C.: Physical Assessment and the Clinical Pharmacist, Drug Intell. Clin. Pharm. 11: 200-203 (Apr.) 1977. 2. Bates, B. : A Guide to Physical Examination, J. B. Lippincott, 1st Ed., Philadelphia, Pa., p. 31, 1974. 3. Prior, John A. and Silberstein, Jack S.: Physical Diagnosis, 4th Ed., C. V. Mosby Co., St. Louis, Mo., p. 102, 1973. 4. Wilkins, R. et al.: Clinical Symposia, Evaluation of Hypertensive Patients, Ciba-Geigy, Summit, N.H., p, 26, 1972. 5. Englemann, K., et al.: Elevation of Arterial Pressure. (Ch. 33) In Harrison's Principles of Internal Medicine, 7th Ed., McGraw-Hill Book Co., New York, N.Y., p. 190, 1974. 6. Kohner, E. M. and Oakley, N. W.: Metabolism 24: 1085, 1975. 7. Meyler, L. and Peck, H. M.: Drug-Induced Diseases, 4th Ed., Excerpta Medica, Amsterdam, pp. 524-533, 1972.

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References

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