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CHAPTER 8 Factors That Complicate Eye Examination in the Older Adult LYMAN C. NORDEN A ging adults undergo and adjust to many physical and emotional changes. Although many of these changes may be unrelated to their...

CHAPTER 8 Factors That Complicate Eye Examination in the Older Adult LYMAN C. NORDEN A ging adults undergo and adjust to many physical and emotional changes. Although many of these changes may be unrelated to their listening devices may not work as well as expected by not adequately screening out back- ground noise or helping isolate desired fre- eyes or vision, they can make an eye examina- quencies. These may be among the reasons why tion more difficult and more time-consuming older adults who have hearing aids sometimes than is customary for younger patients. The choose not to wear them. widely varying reasons for this are broadly Whether or not the patient is wearing a classified in Box 8-1. hearing aid, communication can always be Knowing how to recognize and overcome improved by reducing background noise, these problems can make the examination both facing the patient, and speaking with deliberate more effective and more efficient. This chapter clarity. Close the door and eliminate as much describes eye examination techniques adapted ambient noise as possible. Leave the room lights specifically to older patients. on so the patient can see the examiner’s face and lips. Use as few words as possible, with as HEARING IMPAIRMENT few syllables as possible. Add slight emphasis Hearing impairment is a common problem to word sounds that are easy to hear and slight associated with aging. It is more prevalent pauses to separate word sounds that are hard to among older patients than is visual impairment, hear. Sounds associated with the letters h, t, and and it can greatly impede the clinical assess- d are relatively easy to emphasize with a little ment of vision.16 Depending on the population extra push from the diaphragm. Softer sounds being served, 25% or more of those 65 years associated with the letters z, sh, r, m, and n are or older and 50% or more of those older than hard to emphasize but become easier to hear 80 years are hearing impaired. when followed by a slight pause. A good Hearing impairment associated with aging example of this is heard in the way a sergeant usually manifests as difficulty with higher calls a room full of soldiers to attention. He pitched sounds that is made worse by back- does not shout, “Room, attention.” He shouts, ground noise. Simply speaking louder does not “Hroomm… ahTenn… Hutt.” Of course this always work with hearing-impaired older extreme is not necessary with patients, but adults, especially if a louder voice results in clinicians can speak purposefully from the a higher pitch. It also means that assistive diaphragm, adding emphasis to hard sounds 163 164 ROSENBLOOM & MORGAN’S VISION AND AGING BOX 8-1 Problems Related to Communication or the Physical Examination Communication Impaired hearing Impaired cognition (dementia) Impaired affect (depression) Complex medical/ocular history Physical examination Limited mobility/examination environment Diminished quality of vision Fig. 8-1 Pocketalker used to amplify examiner’s BOX 8-2 voice for hearing-impaired patient. Recommendations for Improving Communication with the Hearing Impaired possible to the mouth to selectively amplify the voice. Lightweight headset earphones are avail- Move to within 3 to 4 feet of the patient. able for added convenience and for use over a Position self with eyes at the patient’s eye level. patient’s existing hearing aids if necessary (see Ensure that mouth and face are optimally visible to the patient. Chapter 9 for further discussion of auditory Ensure the patient is paying attention before impairments in the older adult). speaking. Identify the topic of conversation and avoid sudden COGNITIVE IMPAIRMENT changes. The prevalence of cognitive impairment among Speak at normal to slightly louder than normal volume, but do not shout. older patients is not as easily determined as is Speak at normal to slightly slower than normal pace. hearing impairment. Depending on methods Be concise. and criteria used, reports range that from 1% of Say every word clearly. persons aged 60 years and younger have a cog- Emphasize key words by saying them a little more nitive impairment to 33% of persons older than slowly. Follow key words with a slight pause. 60 years have a cognitive impairment.5,9,22 One Use gestures that emphasize what is being said. study of community-dwelling older adults Give the patient time to respond, and never end a found that 3% to 11% have dementia.4 Unlike statement with an abrupt “OK?” the hearing impaired, the cognitively impaired Do not simply repeat missed statements; rephrase do not self-report their condition and usually them. Ask the patient to repeat information as needed to respond to questions as though they both hear ensure comprehension. and understand—but they may not respond reliably. Neuropsychologists are able to detect and and pauses to soft sounds. A clinical example of categorize cognitive impairment with a highly this technique is “Hwhitch is PbeTTer… specialized battery of tests, such as the Wechsler Hwon… or Two (Box 8-2)?” Adult Intelligence Scale. Less specialized but If despite these measures a hearing problem highly popular is the Mini-Mental Status Exam, persists, a readily available assistive listening with test items such as “Spell world back- device known as the Pocketalker can be kept in wards.” More basic are three simple questions the examination room for use as needed. The testing orientation to person, place, and time: Pocketalker (Williams Sound Co., Eden Prairie, (1) “What is your name?” (2) “Where are we Minn.) is a small, single-unit amplifier and now?” or “What is this place called?” and microphone that fits in the pocket and assists (3) “What day is this?” Questions such as these, hearing in noisy backgrounds. It amplifies the however, seem out of place in an eye examina- higher frequencies and picks up sound closer to tion. They are time-consuming, and some its source, providing a better speech-to-back- patients would understandably be offended at ground-noise ratio. As Figure 8-1 shows, the their implication. The practical solution to this user places it in a breast pocket as close as problem is to incorporate elements that require Chapter 8 Factors That Complicate Eye Examination in the Older Adult 165 orientation to person, place, and time into ques- have similar neurobehavioral manifestations.3 tions that also supply useful ocular information. Approximately 2% to 14% of community- The first question or request of the patient dwelling older adults have depression.2 could be, “Tell me your full name.” Although Symptoms of depression include anxiousness, this is actually a command, presenting it more agitation, irritability, sadness, and loss of as a question—raising the voice slightly on the interest. When some of the problems common last word—sounds better and is easier for to older patients are considered, such as loss the hearing impaired to hear. This answers the of a spouse or close friends, chronic pain and “orientation to person” question and serves to illness, decreased mobility, frustration with verify that the right patient data are destined normal memory loss, and need to adapt to for the right patient’s chart. Mistaken patient changing living circumstances, the difficulty in identity is a potential problem in busy clinics making distinctions between normal sadness and institutional settings. and clinical depression can be perceived. In If the patient is seriously cognitively impaired, either case, some difficulty communicating he may be accompanied by a family member or with, and subjectively examining, some older significant other who preempts the patient with adults will occur (Boxes 8-3 and 8-4). correct answers. As a practical matter, and as a Understanding the impact and the signs of matter of courtesy, never begin the interview by both dementia and depression is the first step addressing that person instead of the patient. toward making the eye examination as effective Rather, ask the patient, “Who is this with you and efficient as possible. Recommended exami- today?” If the patient answers, you gain what- nation techniques for working around these ever information comes with the answer, and problems are essentially the same as for normal you avoid offending anyone. If, however, the older adults. Ask brief, directed questions and other person provides an answer such as, “I’m offer clear, discrete choices. his daughter and I’m here with him because he has Alzheimer’s,” the patient’s cognitive status is quickly determined. If serious cognitive impairment is not clearly BOX 8-3 established by the first question, continue with Symptoms of Depression in Older Adults the following questions. Look directly at the patient and ask, “How long has it been since Persistent, vague, or unexplained somatic your last eye examination?” This calls for a complaints calculation that represents a fairly high level of Memory complaints or problems Difficulty with concentration mental ability. Despite their ability, however, Confusion, delusions, or hallucinations many patients will reply by naming a year or Social withdrawal a month and year, which, if correct, indicate Loss of interest in normally pleasurable activities orientation to time. The immediate follow-up Persistent sadness, hopelessness question of “Where was that [eye examination] Decreased appetite Sleep disturbances done?” indicates orientation to place. Irritability or demanding behavior This brief line of questioning provides useful Lack of attention to personal care information on both cognitive status and ocular history. The next question to ask is, “Did the doctor say whether you have any eye disease?” Most older adults remember terms such as “cataract” or “glaucoma,” and this question BOX 8-4 leads into the medical/ocular history phase of Signs of Dementia the interview. Changes in memory, personality, and behavior DEPRESSION Asking the same questions repeatedly Another potential barrier to communication Getting lost in familiar places Inability to follow directions with older patients is depression. Depression Disorientation to time, people, and places can easily be mistaken for subcortical dementia Neglecting personal safety, hygiene, and nutrition or simply normal aging because all three 166 ROSENBLOOM & MORGAN’S VISION AND AGING impractical to move patients from pretest station COMPLEX MEDICAL/OCULAR HISTORY to examination chair to waiting area (for pupil Older patients have had many years to compile dilation) and back to the chair for examination a lengthy medical/ocular history and often are completion, as is often done with more mobile, willing to relate every detail that any clinician younger patients. For this reason, leaving the wants to hear. In some cases the information patient in the examination chair the entire time being offered is unrelated or too outdated to and starting pupil dilation as early as possible help determine the patient’s current needs. may be preferable. Whether pupil dilation For these reasons, using brief and structured adversely affects the subjective refraction of interview questions is recommended so that patients with absolute presbyopia is a debatable judgment is required of the patient. The three question, but no published data are available medical/ocular history questions presented to provide the answer and many eye care earlier are designed to do that specifically, and providers have found it acceptable. Early pupil the next question does the same. Ask, “What dilation is discussed later. bothers you most about your eyes [today]?” If the patient responds with multiple problems, Wheelchair Patients ask, “Which one would you like to have me to Not all wheelchair patients are wheelchair start with?” Listen for all problems but try to bound. Many can transfer to the examination narrow them down to one at a time. chair with minimal assistance. This can be facili- Once the patient has focused on a single tated by parking the wheelchair as close to a problem, ask, “When did that problem start?” right angle as possible at the front of the exami- Then ask, “Is it worse now than when it nation chair. Once in position, lock the wheels started?” If the patient says “yes,” ask if it is and raise the footrests on both the wheelchair worse now than it was half the reported time and the examination chair to provide a clear interval ago (e.g., 6 months ago for a problem path for the patient. that started 1 year ago). If the patient says If the patient cannot easily transfer to the “yes,” ask, “Is it worse now than it was 1 month examination chair, he or she can be examined ago?” If “yes,” ask, “… 1 week ago?” Finally, while seated in the wheelchair. Specially ask: “Is there anything that makes it better? designed examination chair glides or wheel- …worse?” If clinician and patient are unable chair-accessible stand-and-chair sets are avail- to narrow a chief complaint in this way, the able for such applications. If the examination subjective examination and resulting treatment chair cannot be moved back to allow wheel- will probably be equally unsuccessful. chair access to the stand-mounted phoropter and slit lamp, the examination can still be con- LIMITED MOBILITY/EXAMINATION ducted with handheld instruments and trial ENVIRONMENT frame. Techniques for this are described below. Mobility of older patients can greatly influence the course of an eye examination, as can a Bedridden Patients limiting examination environment (e.g., nursing Bedridden patients can be examined only with home). Patients may generally be classified as handheld instruments, and the following tech- ambulatory, wheelchair, or bedridden. Most of niques described as screening procedures can these examination techniques can be useful for be applied to bedside examination as needed all three, although some described below as (see Chapter 18 for a more complete discussion screening procedures may apply to patients of the delivery of vision care in nontraditional restricted to wheelchairs, gurneys, or otherwise settings). limiting environments. DIMINISHED QUALITY OF VISION Ambulatory Patients Diminished quality of vision can result from a Most older patients are able to move about on variety of age-related conditions ranging from their own, although some require a cane or media opacity to reduced contrast sensitivity. walker. The fact that they move more slowly Because these conditions are not resolved by than younger adults, however, can influence optical correction, the eye examination process the course of their eye examination. It may be may be more difficult than usual. The following Chapter 8 Factors That Complicate Eye Examination in the Older Adult 167 examination procedures are designed to help the popular Rosenbaum visual acuity screener overcome these difficulties and make the exami- and a +2.50 DS, alternate occluding flipper, as nation both more effective and more efficient. further described below. Acuity screening thresholds are 20/50 and 20/25 at both distance EXAMINATION PROCEDURES and near. Distance acuity testing is actually per- Patient flow is often less smooth and efficient formed at 10 feet instead of 20 for two reasons: with older patients. Therefore examination (1) most rooms are less than 20 feet long and techniques that move instruments and test pro- (2) communication with older patients is more cedures to the patient instead of moving the effective at 10 feet than at 20 feet (Boxes 8-5 patient to them are generally preferable. For the and 8-6). same reason initiating pupil dilation earlier in As previously stated, the objective in this the examination sequence than is customary type of acuity screening is to estimate quickly with younger patients is helpful. This discussion the level of useful vision in each eye before of examination procedures therefore begins instilling mydriatic eye drops. More precise with early pupil dilation and emphasizes pro- measurement of acuity occurs during subjective cedures that can facilitate early pupil dilation. refraction. After those topics (beginning with confronta- tion fields) the emphasis shifts to examination BOX 8-5 techniques that simplify the patient’s task and Making the Visual Acuity Screener improve subjective reliability. 1. Order a Rosenbaum Pocket Vision Screener and a Early Pupil Dilation +2.50 DS alternate occluding flipper (Fig. 8-2) from a Early pupil dilation means instillation of preferred equipment supplier. 2. Spray paint a standard tongue depressor flat black. mydriatic eye drops as early in the examination 3. Cut out the Rosenbaum 20/400 “7” and “4,” leaving process as possible before subjective refraction. as much white margin around each as possible. This Safe, early pupil dilation calls for three pre- character size of 10.5 mm is equivalent to 20/50 at a liminary steps: (1) assess entering visual acuity, 9.5-foot test distance. (2) rule out preexisting angle closure, and 4. Cut out the 20/200 “8” and “3,” again leaving ample white margins. This character size of 5.25 mm is (3) rule out pupil abnormality. The acuity equivalent to 20/25 at a 9.5-foot test distance. screening method described later can be com- 5. Cut out the 20/40 “4 2 8” and “3 6 5” number sets. pleted far more quickly than formal acuity This character size of 1.5 mm is equivalent to 20/50, measurement and can actually make its later or 1 M, at 16 inches. (Disregard the printed statement measurement more efficient. Ruling out pre- on the card about using a 14-inch test distance.) 6. Cut out the 20/20 “4 2 8” and “7 3 9” number sets. existing angle closure is more applicable and This character size of 0.75 mm is equivalent to reliable than predicting its occurrence, as is 20/25, or 0.5 M, at 16 inches. generally attempted in a slit lamp examination. 7. On one side of the tongue depressor, and at Assessing pupils is often more difficult in older opposite ends, glue the larger number sets: the “7” patients because of small pupil size and minimal and “4 2 8” and the “4” and “3 6 5” as shown in Figure 8-3. (Fingernail polish works well for this.) reactivity. The anterior segment screening 8. On the other side of the tongue depressor, glue the method described later is useful for those cir- smaller number sets as shown in Figure 8-3. cumstances in which a slit lamp examination is not possible. Visual Acuity Screening The two objectives of this method of screening visual acuity are (1) to determine how well the patient is able to function visually in the average room environment, regardless of whether one or both eyes are used in producing that vision; and (2) to determine how well each eye functions on its own, as an indicator of possible ocular disease. Efficiently accomplishing these Fig. 8-2 +2.50/occluder flipper bar for efficient two objectives calls for a special adaptation of monocular acuity screening at near. 168 ROSENBLOOM & MORGAN’S VISION AND AGING BOX 8-6 Using the Visual Acuity Screener 1. Start with the eyeglasses the patient is already wearing (Fig. 8-4). Do not ask the patient to look for or put on eyeglasses he or she might be carrying. This usually takes more time than it is worth. a. If the patient relies on eyeglasses for distance vision, he or she will most likely be wearing them. b. If the patient has eyeglasses and is not wearing Fig. 8-3 Visual acuity screener. 20/50 numbers are them, they can be retrieved and neutralized later on one side and 20/25 on the other. while waiting for the pupils to dilate. 2. Hold the acuity screener up approximately 10 feet from the patient, with the larger numbers facing the patient, and ask the patient to read the number at the top (“7” or “4”). a. If the patient reads it, turn the side with the smaller numbers toward the patient and ask the patient to read the number at the top (“8” or “3”). i. Record the acuity accordingly as either “OU 20/50” or “OU 20/25.” ii. Technically, the acuity is “10/25” or “10/12.5,” but recording its 20-foot equivalent simplifies data recording and later analysis. b. If the patient is unable to read the larger number at 10 feet, gradually move closer until the patient is able to and record it as “(test distance)/ 25 = 20/(25 × 20/test distance).” For example, if the large number had to be moved in to 5 feet for recognition, the acuity would be recorded as Fig. 8-4 Use of the +2.50/occluder flipper over a “OU 5/25 = 20/100.”Again, recording the 20-foot patient’s existing eyeglasses. Always direct the equivalent simplifies more formal acuity patient’s gaze through upper half of the spectacle measurement later. lens in case he or she is wearing multifocals. 3. Use the +2.50/occluder flipper to assess near acuity for each eye. a. If the patient is wearing bifocals, trifocals, or progressives, have the patient look only through the distance portion with the +2.50 flipper lens of anterior structures is similar to that produced held in front. Regardless of the type of spectacle by the slit lamp at low power. The only thing worn by the patient, save time by having the not produced is a parallelepiped/optic section patient use only the area slightly above the coming from a focused light source. This rules vertical midpoint of the lens. out the van Herrick angle assessment technique b. If the patient is able to read the smaller number set with the right eye, record it as “OD 0.5 M.” but still leaves the shadow test using a separate, If the patient is unable to read the larger number handheld light source at the temporal canthus. set with the left eye, for example, record it as Predicting that an angle will close with pupil “OS worse than 1 M.” dilation is difficult at best, with or without a slit lamp. More important in anterior segment assessment is ruling out an already established, asymptomatic angle closure. Discovering a Anterior Segment Screening closed angle later in the examination raises the Screening the anterior segment involves using troubling question of whether the examiner the binocular indirect ophthalmoscope and 20 D closed the angle when he or she dilated the lens as an illuminated loupe (Fig. 8-5). This is pupils. If the clinician can confidently say no accomplished by positioning both the con- signs of angle closure were present before dila- densing lens and examiner closer to the patient tion, the diagnosis and need for treatment will than the usual working distance for indirect be clear. If, on the other hand, a closed angle is ophthalmoscopy. The resulting magnification discovered before dilation, the diagnosis will Chapter 8 Factors That Complicate Eye Examination in the Older Adult 169 Slit Lamp Examination If the examination environment permits more comprehensive assessment, a portable slit lamp is highly recommended. The focused slit beam enables better assessment of corneal integrity, anterior chamber features, and clarity of the media (e.g., cataracts). Current examples of readily available portable slit lamps include Zeiss HSO-10 (Carl Zeiss Meditec AG, Jena, Germany), Kowa SL-14/15 (Kowa Optimed, Inc., Torrance, Calif.), Clement Clarke 904 (Clement Fig. 8-5 BIO-20D lens used as an illuminated loupe Clarke International, Harlow, England), Heine by shortening the distance between both the exam- HSL 150 (Heine Optotechnik, Herrsching, iner and lens and the patient and lens. Germany), and Scan-Optics SO-850 (Scan-Optics, Manchester, Conn.). The Zeiss, Kowa, and Clement Clarke instruments offer similar fea- tures, including rechargeable batteries for added portability; nevertheless, they will occupy con- siderable space in a trunk used to transport portable eye care instruments. The Heine and Scan-Optics instruments are smaller but offer fewer options for control of the slit beam. Tonometry Tonometry before pupil dilation is highly recommended to avoid the problem of later discovering an elevated intraocular pressure with a normal-appearing anterior chamber. A portable tonometer is suitable for this, and an Fig. 8-6 Swinging flashlight test with condensing added benefit is that the use of an anesthetic at lens positioned to observe the left pupil as the BIO- this point usually enhances the effect of mydri- 20D loupe light is swung from right eye to left eye. atic eye drops. Current examples of readily available portable or handheld tonometers include Perkins (Clement Clarke International not be acute-angle closure and the treatment Ltd, Harlow, United Kingdom), Kowa HA-2 may not have to be emergent. Signs of angle (Kowa Optimal Inc., Torrance, Calif.), Tono-Pen closure that can easily be seen with the BIO-20D (Reichert Ophthalmic Instruments, Depew, loupe include venous congestion; steamy cornea; NY), Keeler Pulsair (Keeler, Windsor, England), and fixed, distorted, mid-dilated pupil. Reichert PT100 (Reichert Ophthalmic Instru- The next most important part of the anterior ments, Depew, NY), and Schiotz (Sklar segment assessment is pupillary reactions, espe- Instruments, West Chester, Pa.). Each has its cially if reduced acuity of one eye is present, unique advantages and disadvantages. The because this calls for a careful swinging flash- Perkins requires subdued room lighting and light test (Fig. 8-6). This, too, is easily done with proximity, sometimes awkward, to the patient. the BIO-20D loupe by holding the lens in place The Pulsair and PT100 are electronic, noncon- before the suspect eye and swinging the BIO tact instruments that are heavier and less light from eye to eye. Then repeat, holding the portable than the others. The Schiotz is the least lens before the opposite eye. The magnification expensive and most portable but requires the produced by the condensing lens and the bright patient to be reclined, is hard to sterilize, and illumination provided by the light beam make measures by indentation rather than applana- even small pupil movements more visible. tion. A clinical study comparing all but the 170 ROSENBLOOM & MORGAN’S VISION AND AGING PT100 to standard slit lamp Goldmann tonometry but may manifest as a confrontation field defect showed acceptable reliability for all instruments.21 include chronic glaucoma, anterior ischemic optic neuropathy, and branch retinal artery Combining Mydriatic Eyedrops occlusion. These disorders manifest as differen- Instilling eyedrops in an older adult’s eyes tial visual field sensitivity across the horizontal can be a remarkably time-consuming process. midline, either as an altitudinal hemianopsia or The older adult has considerable difficulty in a wide nasal step defect. tilting the head back, and the cul-de-sac is Efficient screening for these types of visual usually able to hold only a small amount of field defects calls for a confrontation technique instilled fluid. This means that using both in which the examiner, not the patient, occludes tropicamide and phenylephrine hydrochloride the eye not being tested (Fig. 8-7). One of the (Neo-Synephrine) would normally call for at examiner’s hands provides the occlusion while least two instillations per eye, requiring a the other provides the traditional finger counting longer than usual waiting time between instilla- stimulus. Time is saved by first testing the tions. This problem can be overcome by pre- patient’s right visual field of each eye (the right mixing the tropicamide and phenylephrine eye’s temporal field followed by the left eye’s hydrochloride in a single, appropriately marked nasal field) and then the left visual field of each bottle. This can be done by a compounding eye (the left eye’s temporal field followed by pharmacist. A less expensive option is to use the right eye’s nasal field). Save more time by the hydroxyamphetamine-tropicamide combi- first turning the patient’s head toward the right nation, Paremyd (www.akorn.com). before testing the right field, and then toward the left before testing the left field. This will After Mydriatic Instillation keep the patient’s nose from obstructing the Once the mydriatic eye drops have been inferior nasal field. When turning the patient’s instilled, attention can shift to completing the head, hold it gently with both hands until the rest of the examination. At this point, the patient properly resumes fixation on the exam- following test items have already been completed iner’s nose. If an apparent depression is found and may be recorded: (1) preliminary history in either eye’s temporal field, check for differ- (as with any patient, the history continues ential sensitivity across the vertical midline. If throughout the examination), (2) preliminary an apparent depression is found in either eye’s acuities, (3) external examination to include lids, nasal field, check for differential sensitivity lashes, conjunctiva, cornea, and anterior chamber, across the horizontal midline. Some patients and (4) pupils. The examination can now pro- have great difficulty understanding questions ceed with visual field screening. about differential sensitivity. Try asking the patient, “Is my hand easier to see here, or here?” Confrontation Fields (quickly moving the hand from one quadrant to When field screening methods for the older the other). Then say, “Tell me when it becomes adult are decided, the significant patient health easier to see” (while moving the hand across risks and the potential yield from testing the midline in question). should be considered. Disorders that may Confirming and classifying an apparent manifest only as visual field defects and other- visual field depression can often be problematic. wise be hidden to physical examination are The examiner’s hand may be less visible to the hemispheric cerebrovascular disease (stroke) patient in one area because of poorer contrast and chiasmal disease (pituitary or compressive against a nonuniform background. Moving the vascular disease). Stroke damage manifests as hand from one area to another and asking the homonymous hemianopsia, which can reliably patient to compare what was seen often raises be detected with confrontation fields.13 Chiasmal the question of subjective reliability. These disease usually manifests as either bitemporal problems can be minimized by using a pair of or junctional pattern field defects, both more 20/200 tumbling E’s for simultaneous presenta- apparent superiorly than inferiorly.11,19 tion (Fig. 8-8). The stark black-and-white con- Disorders that may not be easily detectable trast of the E is not affected by a nonuniform by physical examination (i.e., ophthalmoscopy) background behind the card, and having the Chapter 8 Factors That Complicate Eye Examination in the Older Adult 171 A A B B C C Fig. 8-8 Tumbling E confrontation field technique. Fig. 8-7 Finger count confrontation field technique. Subjective reliability is improved by having the A, The patient’s head is turned slightly to the right so patient indicate the direction of the letter’s legs (A). his nose will not obstruct the right hemifield of the Simultaneous presentation of two high-contrast left eye. The right and left hemifields of both eyes are targets provides more reliable comparisons across quickly screened with this technique. B, Testing of vertical (B) and horizontal (C) midlines. the right eye’s superotemporal field. C, Testing of the left eye’s inferonasal field. Turn the patient’s head slightly to the left to screen each eye’s left hemifield. is also easier for a patient to see when a large, tumbling E is used. The examiner will need both hands free so that if the patient is unable to patient state the direction of the E provides a occlude his or her own eye reliably, a tie-on eye better indication of subjective reliability. Each patch can be applied. quadrant can be tested with a single E, and Unfortunately, some patients cannot under- paired quadrants can be compared with simul- stand the simple instruction, “Look at my nose taneous presentation of two Es. Change on and tell me which way the E [off to the side] crossing either a vertical or horizontal midline is pointing.” If the patient erroneously but 172 ROSENBLOOM & MORGAN’S VISION AND AGING accurately looks at the E in each quadrant, his Standard Snellen acuity charts have a few or her fields are probably full to confrontation. practical limitations that may influence exami- If the patient seems to ignore movement of the nation of older patients. The progression of E in one quadrant but responds as soon as it is letter size is not uniform, and unequal numbers moved into another quadrant, the first quad- of letters are used on each line. Also, the rant is typically depressed. recording system does not accurately account for a patient’s ability to read most but not all of Specialized Field Screening Instrumentation the letters on one line, some of the letters on the Visual field screening instruments may be next line, and sometimes one or two letters on a useful in the examination of older patients if third line. These factors combine to cause some mobility and cognition are not a problem. One inconsistency in measuring change in vision widely used field screening instrument, the over time. The logMAR (log of the minimum Humphrey FDT (frequency doubling tech- angle of resolution) chart design helps mini- nology) (Carl Zeiss Meditec AG, Jena, Germany), mize these errors by maintaining consistency is table mounted and must either be moved to in visual demands from one line to the next. the patient or the patient moved to it. The FDT Clinical considerations in adopting a logMAR perimeter is specifically designed to detect chart system include the need to learn a new glaucomatous field defects and has been shown recording system and a slight increase in test to miss neurological defects such as hemianopsia time.15 Regardless of which acuity system is and quadranopsia.8,20 Consequently, it may be a preferred, an important feature for examination useful adjunct to confrontation field screening of older patients is the ease with which letters but should not be relied on to replace it. can be isolated. A similarly portable visual field instrument, Precise measurement of threshold acuity at the Oculus Easyfield (Oculus, Dutenhofen, near requires careful control of test distance, Germany), uses a more conventional, Goldmann which is difficult with older patients. More III stimulus that should be more likely to detect important, however, than precisely measuring neurological disorders than the FDT, but no near acuity is determining the patient’s pre- reliability studies have been published to con- ferred working distance. Let the patient hold firm this. Unlike the FDT, the Easyfield requires the near point card and ask what working an auxiliary lens to neutralize refractive error, distance he or she prefers. Make note of the and the eyepiece design requires accurate and patient’s preferred working distance so that, steady positioning of the patient—often a assuming no visual impairment, an add power problem with older patients. corresponding to that distance can be later prescribed. Visual Acuity Measurement The popular method of presenting a full acuity Contrast Sensitivity chart and asking, “What is the smallest line you Standard visual acuity measurement can give a can read?” does not work well with many older misleading impression of the older patient’s adults. Often, the older adult will simply start visual status. The patient may be able to read at the top and attempt to read every letter in 20/20 size letters in the clinic but still report turn, presumably expecting the examiner to worsening vision in everyday life. Much of this decide which is the smallest line that can be may be attributed to contrast sensitivity, which read. The patient may in fact be seeing none of is known to decline with advancing age.17,18 the letters clearly enough to say which can be Contrast sensitivity can be measured in the correctly identified. To save time, isolate a ver- clinic with specially designed charts such as the tical line of letters arrayed with the top letter Vistech Vision Contrast Test System (Vistech being the size the patient was able to read in the Consultants, Dayton, Ohio), the Pelli-Robson preliminary acuity screening. Then isolate a test, or the Bailey-Lovie chart. Measuring low- horizontal line of letters of the size the patient contrast acuity in the clinic offers some reassur- was just able to read in the vertical array. ance to the patient that his or her visual Consider this the threshold line for refinement symptoms are understood, and research sug- by subjective refraction. gests that impaired low-contrast acuity is pre- Chapter 8 Factors That Complicate Eye Examination in the Older Adult 173 dictive of impaired standard acuity in later improve it a little more—the expected end point years, but an optical prescription is still best being 20/20 or better with no further improve- determined by using standard, high-contrast ment on further lens changes. For an older acuity charts.10 Most important, 20/20 visual adult with a threshold acuity of 20/30 not due acuity does not always mean “normal” vision to refractive error, a progression of 0.25 D lens for the older patient, and new eyeglasses that changes produces incremental changes in focus improve Snellen acuity may not improve the too small to appreciate in subjective refraction. patient’s overall quality of vision as hoped. For a threshold acuity of 20/30 (regardless of its cause), lens changes in 0.50 D steps are more Subjective Refraction likely to produce a useful subjective response. If Emphasis on threshold acuity is important in the 20/30 acuity is caused by myopia, −0.50 DS subjective refraction of the older adult. Many will likely correct it to 20/20 and +0.50 DS will older adults have difficulty saying whether likely degrade it to approximately 20/50.6,7 If progressive lens changes actually make vision the 20/30 acuity is caused by something other progressively better, as occurs with standard than refractive error, neither lens is likely to refraction technique. A classic example of this is improve vision. Similarly, for a 20/50 threshold seen in refraction of the patient with a nuclear acuity, either +1.00 DS or −1.00 DS should sclerosis cataract. The patient reports gradually quickly isolate refractive error from whatever worsening blur and with current spectacles sees else may be limiting vision. 20/30. Subjectively the patient accepts incre- This method of subjective refraction is mental steps of −0.25 sphere totaling a diopter similar to the Humphriss immediate contrast or more of additional minus over the habitual technique of presenting lens choices on oppo- prescription, but he still sees only 20/30. Then site sides of the presumed refractive end when asked to compare the new refraction to point.12 In this adaptation, the technique is his habitual prescription, he says it looks referred to as “bracketing” instead of “imme- approximately the same. As Figure 8-9 shows, diate contrast” and the principle is applied to this method of subjective refraction accom- both cylinder power and axis as well as to plished little more than moving a succession of sphere. If at least some of the subjective blur is similar-appearing blur circles across the fovea. attributable to refractive error, some subjective The effect on refraction is similar in other cases improvement should occur with either one or of blurred retinal imagery from age-related the other opposing lens options. Also, if one causes ranging from hazy media to macular lens change produces a subjective improve- degeneration. The way to overcome its adverse ment, its opposite should produce a subjective effect on subjective refraction is to make lens decline. This is a good way to verify subjective changes in steps consistent with the patient’s responses when patient misunderstanding, threshold level of acuity. disinterest, or cognitive impairment may be For a younger adult starting with a threshold present. acuity of 20/30 because of myopia, a −0.25 D Integral to the Humphriss technique is the lens change would be expected to improve immediacy between opposing lens presenta- vision slightly and with another −0.25 D to tions. This is not possible with a phoropter Fig. 8-9 Effect of nuclear sclerosis cataract on subjective refraction. Small, incremental spectacle lens changes serve only to move similar-appearing blur circles across the fovea, making refractive end points hard to establish. 174 ROSENBLOOM & MORGAN’S VISION AND AGING A Fig. 8-10 ±, Sphere/cylinder flippers used for bracketing refraction. Cylinders are mounted at right angles to one another. The 0.25 D flipper should be used for 20/20 to 20/25 threshold acuity, the 0.50 D for 20/30 to 20/40 threshold acuity, and 1.00 D for 20/50 or worse. because of intervening lenses between the two intended choices. Three lenses are between the B ±0.50 choices and seven lenses are between ±1.00. Just as with the well known Jcc test, the ± bracketing technique works best when the interval between presentations seems, to the patient, almost immediate. This requires the use of handheld lenses in front of either the phoropter or the trail frame. The ±0.50 Jcc and ±0.25, 0.50, and 1.00 sphere/cylinder lens flip- pers (Fig. 8-10) can easily be obtained from an ophthalmic equipment supplier. Because the introduction of an additional test lens sometimes degrades vision from that pro- duced by the base lens correction already in the C phoropter or trial frame, giving the patient Fig. 8-11 Bracketing refraction method using ± lens three choices is sometimes helpful (“Which is flipper and trial frame. Flipper lens strength is better, one, two, or three?”), with one of the chosen to correspond with the patient’s threshold choices being without the additional test lens acuity. First check the sphere (A), then the cylinder in device (Fig. 8-11). the four major meridians (B and C). The bracketing refraction method enables two useful verification steps: (1) if one test lens improves vision, its opposite should degrade it, tion produces no further improvements in and (2) if a given test lens choice leads to a threshold acuity. With the Jackson Cross change in the base lens, a new threshold acuity Cylinder, it may be necessary to select a new, line should accompany that change. Isolating slightly bigger threshold line and isolate the that new line then facilitates the next ± brack- roundest letter on that line. The objective is to eting choice. encourage a response of “better or worse” Cylinder power and axis are refined with the rather than an attempt to read all the letters. Jackson Cross Cylinder when flipper bar refrac- Some acuity charts, such as the Marco CP 670 Chapter 8 Factors That Complicate Eye Examination in the Older Adult 175 (Marco, Jacksonville, Fla.), offer a pattern of sphere, then cylinder) directly from the trial round dots for this purpose. case may be easier. When the retinoscopy end Although the emphasis in this section is on point is reached, remove the working lens reliability and efficiency in reaching a subjec- power (1.50 D if using the standard 67-cm tive refraction end point, a brief discussion on retinoscopy distance) from the base sphere and establishing a starting point is in order. The ini- start the subjective refraction. If retinoscopy is tial base lens selection can be derived from any, made difficult by small pupils, media opacities, or a combination, of the following: current pre- eye movements, and so forth, its accuracy will scription, retinoscopy, or autorefraction. The improve with pupil dilation. current prescription is often the most reliable Autorefraction is an increasingly popular place to start, assuming the patient is not bor- method for establishing a starting point for sub- rowing someone else’s eyeglasses. Spectacles jective refraction. Although validation studies can easily be neutralized outside the normal have shown autorefraction outcomes to be com- office setting with a portable lensometer. Portable parable to both retinoscopy and subjective lensometers are lightweight, battery powered, refraction, for young adults no known compar- and easily obtained through Internet sources, if isons have been made with older subjects.1,14 not available from current ophthalmic suppliers Factors common in older patients that appear to (Fig. 8-12). diminish accuracy in autorefraction include Retinoscopy is traditionally the preferred small pupils, media opacities, and unsteady method for establishing a starting point for fixation. Reliance on autorefraction in such cases subjective refraction and is understandably can be improved by immediately following the more difficult with handheld lenses than with a initial test with a retest. Paired readings that phoropter. Several types of handheld retinoscopy match are more likely to provide a reliable lens bars are available for nonphoropter appli- starting point for subjective refraction. Table- cations, but they have some important limita- mounted autorefractors in an office setting with tions. The larger ones consist of multiple pieces efficient wheelchair access and sufficient ancil- that must be individually manipulated. The lary staffing can be useful in the examination of smaller ones consist of fewer pieces, but the older patients. Portable autorefractors are also small lenses are hard to keep in proper align- available for use in other settings where inherent ment with the patient’s pupil. Both large and limitations of the examination environment small retinoscopy bars require mental transpo- must be weighed against accuracy in refraction. sition of an optical cross into a spherocylinder equivalent for the trial frame. For some this can Trial Frame Verification/Demonstration be difficult if only done infrequently. If so, using When the distance refraction is completed, the the trial frame and individual lenses (first patient can best understand its effect by seeing it in a trial frame. The patient can easily com- pare it to his or her current eyeglasses and more easily understand cases in which a new pre- scription does not provide the level of vision expected. The patient can actually see firsthand when lens changes in either direction fail to improve vision. Unfortunately, such demonstra- tions are sometimes necessary when the patient presents with the expectation that a simple visit to the optometrist will result in restoration of good vision—as may have been the case for many years before. With the distance correction in a trial frame, arriving at a suitable near point addition by using another set of specially designed lens flippers is a useful clinical method (Figs. 8-13 Fig. 8-12 Portable lensometer. and 8-14). 176 ROSENBLOOM & MORGAN’S VISION AND AGING A A B Fig. 8-14 Bifocal add flippers used with trial frame to determine the best prescription for the patient’s customary working distance (A). The flipper can also be used to show first-time bifocal wearers how to use them (B). B Fig. 8-13 Bifocal add flippers for use with trial frame. A and B, Opposite sides with the label indicating the lens strength below. Higher adds, up to +3.50, can be BOX 8-8 obtained by overlapping the two flippers. Recommendations for Making Trial Frame Refraction More Efficient In the lens tray, alternate the lens handle positions to make 0.50 D increments easy to find. Some patients are able to hold the lens tray on their lap, providing easy access to the lenses. Raise the arms on the examination chair if necessary to make BOX 8-7 room for the lens tray. For the patient’s right eye, use only lenses from the Why Trial Frame Refraction May Be lens bank on the patient’s right side, and vice versa Preferable to Phoropter Refraction for the left eye. When changing a lens in the trial frame, always put Patient has difficulty staying in position at the the old lens back in its designated slot. phoropter. Always place base sphere lenses in the back cell of Patient has more difficulty hearing when seated the trial frame and cylinders in the front cell. behind the phoropter. Use Hallberg or Janelli clips over the patient’s Eccentric viewing can be noted and evaluated. existing spectacles instead of a trial frame. Phoropter too bulky in the front to allow effective Neutralize the resulting lens combination with the use of handheld ± test lenses. lensometer to determine the final prescription. Chapter 8 Factors That Complicate Eye Examination in the Older Adult 177 9. Grigsby J, Kaye K, Shetterly SM, et al: Prevalence Trial Frame Refraction of disorders of executive cognitive functioning In some cases, trial frame is the only possible among the elderly: findings from the San Luis means of refraction; in others it may be prefer- Valley Health and Aging Study, Neuroepidemiology 21:213-20, 2002. able to phoropter refraction. Box 8-7 lists several 10. Haegerstrom-Portnoy G: Vision in elders— reasons why it may be preferable. Box 8-8 lists summary of findings of the SKI study, Optom Vis several recommendations for making trial Sci 82:87-93, 2005. frame refraction more efficient. 11. Halle AA, Drewry RD, Robertson JT: Ocular If the patient’s vision is impaired, requiring a manifestations of pituitary adenomas South Med higher add and closer working distance, some J 76:732-5, 1983. additional time will probably need to be set 12. Humphriss D, Woodruff EW: Refraction by aside for patient education and possible low immediate contrast, Br J Physiol Opt 19:15-20, vision rehabilitation. 1962. These examination techniques are designed 13. Johnson LN, Baloh FG: The accuracy of con- to help the patient understand and make his or frontation visual field test in comparison with automated perimetry, J Natl Med Assoc 83:895-8, her own choices from the available treatment 1991. options. They can be used for patients of all ages 14. Jorge J, Queiros A, Almeida J, ET AL: but are particularly helpful for older patients Retinoscopy/autorefraction, which is the best with multiple age-related health problems. starting point for a noncycloplegic refraction, Optom Vis Sci 82:64-8, 2005. REFERENCES 15. Laidlaw DAH, Abbott A, Rosser DA: Development 1. 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