OCULAR POTPOURRI
| READING AND THE EYES, PART 1—David B. Granet, MD, Anne F. Ratner Professor of Ophthalmology and Pediatrics,
University of California, San Diego, School of Medicine
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| “Vision” defined: ability to perceive visual stimuli (narrowly defined as smallest letters seen on Snellen chart; now
know more with, eg, contrast sensitivity test)
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| Components of reading: focus and convergence; accommodation for near focus and resolution of image into component
parts (letter identification); letters combined make sound groups called phonemes; next, whole words identified;
reading not possible until meaning of word understood (meaning may change in context of next word); words assembled
and meaning determined in context of sentence, paragraph, and entire text; only first few steps involve eye
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| Directionality: meaning of objects or scenes usually static, even if turned upside down or reversed (not true of letters)
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| Tracking: no one reads by smoothly scanning across page; eye jumps from word to word (reverses occasionally), then
jumps again; staircase saccade across page; in intervals between saccades, information obtained; decoding must connect
to language in brain for comprehension; reading pathway in brain—visual cortex, angular gyrus, Wernicke’s area
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| Dyslexia: unexpected difficulty with reading in children and adults who otherwise possess intelligence, motivation, and
schooling necessary for accurate and fluent reading; late 19th century explanation as dysfunction of visual perception and
visual memory misleading; myths —essence of condition mirror writing and reversed-order letters and words; more
prevalent in boys; can be outgrown; not seen in smart people; reversing letters not essence of dyslexia—normal individual
able to read text even if letters reversed; study by Shaywitz—functional magnetic resonance imaging (fMRI) used
to examine brain function; novice readers use parietotemporal region to break down words, but experienced readers rely
on occipitotemporal region; dyslexics read like novice readers (intensive programs can bring improvement); hypothesis
that training eyes can cure dyslexia (not true; becoming expert reader improves eye movement strategies used to read);
eg, baseball players and assembly-line workers develop better eye-movement strategies as they become more expert in
task (not vice versa); reading takes place in brain, not eyes (blind readers of Braille can have dyslexia)
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| School underachievement: associated with learning disabilities and medical conditions (eg, attention-deficit/hyperactivity
disorder [ADHD]); many reasons why children cannot read; role of eyes probably limited to beginning of process
(eg, convergence difficulties, accommodative insufficiency, overuse of accommodation); perform good eye examination
(check convergence and accommodation)
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| READING AND THE EYES, PART 2—Dr. Granet
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| Convergence insufficiency (CI)
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 | CI misdiagnosed as ADHD (Granet et al): symptoms of CI mimic 5 of 9 diagnostic criteria for ADHD (eg, patient seems
distracted and avoids tasks that require much mental effort); children with convergence insufficiency 3 times more
likely to be diagnosed with ADHD
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| Treatment options: pencil push-ups (boring); base-out prism stereography; base-in prism spectacles; surgery; orthoptic
techniques—self-guided vergence exercises can be performed at home using inexpensive software; orthoptics addresses
convergence, divergence, and vertical vergences; according to recent data, it works well in building fusional
amplitudes; home therapy saves money, time, and effort; helpful for true fusional or accommodative amplitude problems
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| CI Treatment Trial (CITT; National Institutes of Health [NIH]): 230 patients with CI, 9 to 18 yr of age, randomized to placebo
vision therapy (VT), home pencil push-ups, home computer exercises, or VT treatment (in-office orthoptics); data
not yet evaluated; at speaker’s center, some children on placebo had best improvement
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| CI questionnaire: answers used to generate standardized symptom score; can be administered to children (helpful for
families)
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| Accommodative insufficiency: chalkboard print clear, but near vision poor; options (corrective lenses; accommodation
training (orthoptics works); accommodative spasm produces clear near vision, but distance vision blurred; children
reading too close become pseudomyopic; if evaluating 6- or 7-yr-old child without cycloplegia, might miss pseudomyopia;
case—child reads 20/50 or 20/80 at distance (with cycloplegia, plano); break spasm with plus lenses at near or, if
needed, use cycloplegics; high accommodative convergence/accommodation (AC/A) ratio—can interfere with reading,
due to difficulty in regulating fusional amplitudes; treatment bifocals (avoids expensive vision training)
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| Evaluating children referred by school: perform visual field testing; determining extent of central loss helps
school understand child’s needs; low-vision aids (as mandated by federal law, visually impaired children entitled to “appropriate”
education; low-vision aids supplied by school as part of individualized education plan); physician can suggest
lighting and contrast settings and prescribe special glasses if needed; best contrast depends on child (speaker lets patient
choose)
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| Behavior vision therapy (VT): “snake oil”; College of Optometrists in Vision Development, American Optometric
Association, and American Academy of Optometry—“vision therapy does not directly treat learning disabilities or
dyslexia”; speaker’s view—despite foregoing, VT misused; not known whether VT works (therapy unproven, despite
anecdotal success); VT may divert family time and resources from more effective strategies for addressing educational
problems; American Academy of Pediatrics, American Academy of Ophthalmology, and American Association for
Pediatric Ophthalmology and Strabismus (AAPOS)—do not recognize behavioral VT as treatment option for reading
disorders
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| Motor training to improve handwriting (study): not VT; administered by occupational therapists; simple test of
saccades and pursuits; significant improvements in handwriting at 12 wk, and eye movement strategies improved; with experience,
experts improve strategies they use to perform tasks; as handwriting improved, changes in eye movements observed;
saccades more accurate because person knows where hand going (not reverse; increased accuracy of eye movements
does not improve hand movement)
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| Reading and hearing impairment: children with hearing deficits cannot decode words phonetically as normal children
do; in sign language, grammar and spelling different; families of deaf children should learn sign language to help
child learn to read; academic achievement delayed in part because language delayed; diagnosis often delayed, although
every newborn tested before leaving hospital; reading aids—include color-coded words and letters to help children see
rhythm of speech
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| Educating parents: present facts to parents about underlying visual disorder (if present); help parents to avoid unhelpful
therapies; reading instruction includes phoneme awareness, use of phonics, and constant practice; single best intervention to improve
reading skills reading with child and reading out loud (correct word emphasis requires understanding of meaning); reading
teachers helpful (resource teachers more common, but trained in special education); main advantage of commercial self-
guided reading products and tutorial centers getting children “psyched” about reading (but most parents can do this themselves);
Schwab Foundation For Learning (schwablearning.org)—parent’s guide to helping children with learning difficulties;
inexpensive products for children; enthusiastic response from parents
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| SELECTING PATIENTS FOR PRESBYOPIC IOL SURGERY—Steven J. Dell, MD, Director, Refractive and Corneal Surgery,
Texan Eye Care, Austin, TX
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| Where did LASIK patients go? they aged; in 2006, average age of baby boomer 52 yr (moving out of laser-assisted
in situ keratomileusis [LASIK] market into presbyopic and premium intraocular lens [IOL] market)
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| Presbyopic IOL market: from 2004 to 2020, United States population >65 yr of age will double; these baby boomers
≈51 yr of age; every 7 sec, boomer reaches 51 yr of age (past laser vision correction [LVC] “sweet spot”)
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| Upgrade IOL market: substantial minority of Medicare patients interested in premium IOLs (in commercial group of
younger cataract patients, >50% interested); LASIK most common elective medical procedure in United States, regardless
of specialty; if 20% of IOL market upgrades to premium IOLs, it would become number 2 elective procedure
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| Incidence of cataracts in individuals <65 yr of age: approximately one-third of patients 45 to 64 yr of age already
have early cataracts
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| Intermediate vision: new category of visual demand; ≈50% of people >50 yr of age spend >1 hr/day on computer; average
20-yr-old spends far more time on computer than reading books, newspapers, or magazines; handheld electronic
device use —increasing 4 times faster than personal computers
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| Cataract patient consultation: “you have a cataract”; explain risks and benefits of treatment; limits to accuracy of biometry;
choice of monovision procedure, presbyopic IOL, or combination; no test for simulating patient’s condition after
surgery; lenses difficult to remove, especially later on; some patients do not like lenses at first; difficult to judge first eye
until second eye done; extra cost; for multifocal IOLs, discuss possibility of postoperative halos, rings, glare, and loss of
visual quality; for Crystalens, need slight amount of monovision to achieve high-grade near vision
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| Speaker’s questionnaire: briefly states that patient has cataract and that it can be replaced with artificial lens; occasionally,
clear lenses also removed; 1) interested in seeing well at distance without glasses? 2) interested in seeing well at
near without surgery? 3) requires patients to pick 3 continuous zones of vision most important to them (some visual compromises
necessary); 4) if you had to wear glasses after surgery for one activity, for which activity would you be most
willing to use glasses (reading fine print, computer use, or distance vision)? some startling answers (many plano cataract
patients want to be myopic); 5) halo question for multifocals; 6) Crystalens or monovision? 7) asks patient to rate personality
on scale, from easy-going to perfectionist
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| Speaker’s discussion: if you want to see well at distance without glasses, need limbal relaxing incision (LRI) or toric
IOL (small extra cost); if you want to see well near and far, based on what you have told me, best procedure(make unequivocal
recommendation); glasses needed in some capacity, but goal decreasing need to bare minimum (if patient
balks, do not perform procedure); offer follow-up LVC, if needed, at discount (not free)
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| Patient’s psychologic makeup: strongly influences satisfaction after surgery; perfectionist with unrealistic expectations
will expect perfection; if patient understands variability of human response to surgery, both sides happier; some patients
never happy; significant percentage of population has untreated mental illness or psychologic issues that adversely
influence how they behave after IOL surgery; 25% of patients >65 yr of age on mental health-related drugs
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| Web site for Dell patient questionnaire (Dell Survey): CRSToday.com
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| RAPID PATHOGEN DETECTORS IN OPHTHALMOLOGY—Richard S. Davidson, MD, Assistant Professor, Department
of Ophthalmology, University of Colorado School of Medicine, Denver
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| Epidemiology of conjunctivitis: most common cause of red eye; most commonly caused by allergy, bacteria, or virus;
adenovirus most common viral cause; ≈50% of patients treated unnecessarily with antibiotics
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Adenoviral Conjunctivitis
| Clinical diagnosis: cultures and polymerase chain reaction (PCR)—must be sent out; expensive; not point-of-care
tests
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| RPS Adeno Detector (Rapid Pathogen Screening, Inc.): point-of-care test; mechanism lateral-flow immunochromatography;
detects common epitopes on hexon protein of adenovirus; identifies all 51 serotypes of adenovirus; 2 antigen-
specific antibodies in device capture viral antigen; Food and Drug Administration (FDA)-approved, with Clinical Laboratory
Improvement Act (CLIA) waiver (can be administered by someone other than physician, eg, technician or medical student);
disposable and easy to use; administration—retract patient’s lower eyelid and soak up tears; transfer to main cartridge and
dip wick in buffer solution; wait 10 min for results to develop; 1 strip=negative, 2 strips= positive; FDA trial (Sambursky
et al)—186 consecutive patients; device compared to viral cell culture and PCR; sensitivity of Adeno Detector 89% (specificity
93%); comment—Adeno Detector helpful diagnostically, easy to use, and avoids unnecessary treatment; may have
greater application for nonophthalmologists; may reduce gentamicin prescriptions and spread of disease by identifying contagious
individuals more rapidly
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Herpes Simplex Virus (HSV) Conjunctivitis
| Epidemiology: ≈150 cases per 100,000 people (45,000 new cases annually); ≈80% epithelial disease (sometimes confused
with epidemic keratoconjunctivitis associated with adenovirus)
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| Rapid pathogen detector for HSV (study): currently recruiting patients
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| Description of device: detects HSV-1 and HSV-2; requires >1000 particles (few false positives); uses tear sample (not as
effective for patients with keratouveitis or stromal keratitis); designed for patients with conjunctivitis or keratitis
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| Inclusion criteria: sample 1—clinically active dendritic keratitis or geographic ulcers; group A (proparacaine, but no trifluridine
[Viroptic] or acyclovir); group B (same as group A, but no proparacaine); group C (no medications within 72 hr);
group D (acute conjunctivitis without iritis or keratitis); sample 2—history of ocular HSV; inactive ≥3 mo; antiviral therapy
permitted; sample 3—acute red eye not associated with dendritic or geographic ulcer (HSV infection not suspected)
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| Exclusion criteria: allergy to cornstarch (component of pad on tip of device); topical ointment used in last 72 hr; stromal
keratitis or uveitis without epithelial disease
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Allergic Conjunctivitis
| Epidemiology: seasonal and perennial most common (accounts for 90%-95%); vernal, atopic, and giant papillary conjunctivitis
more severe
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| Pathophysiology: antigen binds to IgE receptor on mast cell and stimulates reaction; in tear film, normal IgE level <15 ng/
mL (for viral or bacterial conjunctivitis, level 90-110 ng/mL); with allergic conjunctivitis, numbers higher)
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| Clinical diagnosis: look for itchiness, redness, swelling, chemosis, and tearing; many masqueraders (rapid test would be
helpful to determine whether IgE levels elevated)
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| IgE rapid detector (study): strip placed in buffer solution for reading; inclusion criteria—patients >1 mo of age; red
eye presumed allergic (no other comorbidities); exclusion criteria—findings on presentation that do not suggest allergy;
study ongoing
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| On horizon: multipathogen detector
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Suggested Reading
Granet DB et al: Reading: do the eyes have it? Am Orthoptic 56:1, 2006; Granet DB et al: The relationship between
convergence insufficiency and ADHD. Strabismus 13:163, 2005; Robbins SL et al: Vision testing in the
pediatric population. Ophthalmol Clin North Am 16:253, 2003; Sambursky et al: The RPS adeno detector for diagnosing
adenoviral conjunctivitis. Ophthalmology 113:1758, 2006; Scheiman M et al: A randomized clinical
trial of vision therapy/orthoptics versus pencil pushups for the treatment of convergence insufficiency in young
adults. Optom Vis Sci 82:583, 2005; Shaywitz SE et al: Functional disruption in the organization of the brain for
reading in dyslexia. Proc Natl Acad Sci USA 95:2636, 1998; Shaywitz SE, Shaywitz BA: The science of reading
and dyslexia. J AAPOS 7:158, 2003.
Web Sites
Dell patient questionnaire (Dell Survey): CRSToday.com
| Schwab Learning Foundation (Parent’s guide to helping children with learning difficulties): schwablearning.org
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Rapid Pathogen Screening, Inc: rps-tests.com
Educational Objectives
| The goal of this program is to improve the care of patients with reading disorders, presbyopia, or conjunctivitis. After
hearing and assimilating this program, the clinician will be better able to:
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| 1. Evaluate children referred to an ophthalmologist for reading problems.
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| 2. Choose appropriate therapy for children with reading disorders.
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| 3. Evaluate patients for presbyopic intraocular lens (IOL) surgery.
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| 4. Advise patients about the risks and benefits of presbyopic IOL surgery.
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| 5. Describe newer rapid pathogen detectors in ophthalmology.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty members to disclose
relevant financial relationships within the past 12 months that might create any personal conflicts of interest. Any
identified conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary
business or commercial interest. For this program, the following has been disclosed: Dr. Dell has been a consultant
to Advanced Medical Optics, Bausch and Lomb, and Eyeonics.
Acknowledgements
Dr. Granet spoke at New Dimensions in Ophthalmology-2007, held March 29-30, 2007, in Seattle, WA, and sponsored
by Washington Academy of Eye Physicians and Surgeons. Dr. Dell spoke at Controversies in Ophthalmology
, held January 13, 2007, in Los Angeles, CA, and sponsored by the Research Study Club of Los Angeles. Dr.
Davidson spoke at the 30th annual Ophthalmology Symposium, Cornea: The Cutting Edge, held May 18-20, 2007,
and sponsored by the University of California, Davis. The Audio-Digest Foundation thanks the speakers and the
sponsors for their cooperation in the production of this program.
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