Chronic Visual Loss
UBC Ophthalmology Club
2012
Approach
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History, physical, tests
Patient population tends to be the elderly, but 2% of
adults in the US over age 40 have vision <20/40 (Congdon et
al. 2004. Arch Ophthalmol 122(4):477-85.)
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Prevalence increases with age
Early detection may lead to early intervention and
preservation of vision
Primary care is the first screen, know when to refer
Case 1
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55M comes to GP for
routine physical
Has HTN, currently on
thiazide
Denies visual loss, eye pain,
headaches
Sister was taking an eye
drop but not sure what
that’s for
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Exam:
 OD 20/30 OS 20/30
(both 20/25 2 years
ago)
 Pupils equal reactive
 No RAPD
 EOM full
 Confrontational VF
grossly intact
Case 1
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Photo courtesy Dr. Fred Mikelberg
Management:
A. This pt needs urgent
treatment to lower his IOP
B. Refer pt to
ophthalmologist 1-2 weeks
C. Reassess pt in 3 months
D. Increase his thiazide
dose and consider adding a
second antihypertensive
Transillumination defect. (Kuo &
Noecker, AAO 2009)
Pseudoexfoliation. (Shaw, AAO 2003)
Primary Open Angle Glaucoma
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Progressive optic neuropathy of unknown etiology with
persistent VF defect
Risk factors incl. elevated IOP, family hx, race, age, myopia
Sx incl. gradual loss of peripheral visual field
Further tests:
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VF testing of this pt reveals nasal step defect
IOP: OD 29mmHg, OS 23mmHg
Retina tomography shows moderate thinning of nerve fibre
layer
AAO recommends refer pt when:
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disc:cup >0.5 or one cup significantly larger than the other
IOP > 21mmHg or >5mmHg difference between the eyes
Sx of acute glaucoma
Common Rx for glaucoma
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The only pharmacological target is lowering IOP
Alpha agonists(↑drain, ↓aq): clonidine, brimonidine
Beta blocker (↓aq): timolol
CA inhibitor (↓aq): acetazolamide (Diamox)
Prostaglandin analog (↑drain): latanoprost (Xalatan)
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SE of PG analog- iris color change and longer eye lashes
Case 2
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70M c/o decreasing vision in both eyes over last 6 months
to GP
This is particularly bothersome as he is having more
trouble reading and watching TV
No eye conditions in the past
Hx significant for obesity and 50 pkyr smoking, quit 5
years ago
Family history unremarkable
Case 2
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OD 20/80, OS 20/100
(last 2 years decreased)
Pupils equal reactive
EOM full
CVF intact
IOP within normal limits
Fundoscopy:
Amsler grid:
(Khanifar et al. Retinal Physician, 2007)
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What do you tell this patient?
A. he has missed the window for effective intervention
B. he needs immediate antioxidant and zinc supplement
C. his children are at increased risk of this disease
D. his condition probably won’t cause complete blindness
Age Related Macular Degeneration
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2 forms: atrophic (dry) and exudative (wet)
Leading cause of blindness in adults >75 yr, mostly from
exudative form
Multifactorial disease, see characteristic drusen
Early diagnosis enables detection of exudative form, which
can be effectively treated with anti-VEGF agents
Screening in primary care:
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Visual distortions, especially in central vision
Presence of drusen in macula, retinal pigment breakdown
Refer to ophthalmologist for full evaluation
Wet AMD
Monthly
injection,
$1600 per
shot
Case 3
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68F comes to GP with c/o decreased vision in her L eye
She denies double vision or glares, in fact she said she can
read better with her L eye than her R eye now; she wants
to know if her reading glasses are still necessary
No eye disease or trauma
No family hx of eye diseases
Meds include prednisone 20 mg daily for last 2 months
for RA flare
Case 3
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(Espandar, AAO 2009)
OD 20/30, OS 20/50
Pupils equal reactive no
RAPD
EOM full
Confrontational VF full
Fundus visualized,
unremarkable
Management
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What’s your course of action?
A. Inform pt that her cataract is the result of her
prednisone use
B. This pt needs to see an ophthalmologist STAT because
of risk of irreversible visual loss
C. This pt’s presbyopia is improving so she should be
followed up in 6 months at your office
D. Referral to ophthalmologist for evaluation and
treatment options
Cataract
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Etiology: opacified lens
Most commonly associated with increasing age, but also
congenital, DM, steroid use, trauma, radiation
Pt complain of painless gradual unilateral vision decrease
“Second sight” refers to myopic shift as cataract increases
power of lens; this is temporary
Referral to ophthalmologist when decrease in vision
becomes symptomatic and/or interfere with function
Cataract removal+IOL implant is one of the most
frequently-performed and successful procedures in all of
surgery
Other types of cataracts
Cortical cataract
Posterior subcapsular cataract
Implantable IOL
Case 4
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63M with 17 yr hx of Type 2 DM comes to GP to c/o
decrease in vision in both eyes
Denies pain, distortions, double vision
Hb A1c 7.5% despite being on metformin and gliclazide
Also has dyslipidemia, on atorvastatin
No previous eye complaints
Case 4
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(AAO, 2012)
OD 20/40, OS 20/60
Pupils equal reactive, red
reflex present
EOM full VF intact
AC deep and quiet
Fundoscopy:
Diagnosis
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What is the cause of this pt’s decreased vision?
A. Non-proliferative diabetic retinopathy
B. Age related macular degeneration
C. Proliferative diabetic retinopathy
D. Branch retinal vein occlusion
Diabetic retinopathy
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Microvascular complication of DM
Most common cause of vision loss in adults 25-74 yr
In NPDR, vision loss arise from macular edema
In PDR, vision loss can be rapid, secondary to scarring
and vitreous hemorrhage
Ophthalmologist referral when:
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Newly diagnosed DM patient
Eye exam every 1-2 years after
Patient who develop rapid vision change
Glycemic control is the cornerstone of systemic
management. DR is managed with laser and anti-VEGF
PDR
Proliferative disease, characterized by
formation of new and fragile vessels
that form a tangle on the disc and
elsewhere.
Pan-retinal photocoagulation uses laser
to destroy ischemic retina in order to
prevent neovascularization and
preserve the macula.
Summary
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4 most common causes of chronic visual loss and their
features:
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Open angle glaucoma- insidious, treat IOP
Age related macular degeneration- distortions, most common
Cataract- often unilateral, good result with surgery
Diabetic retinopathy- check in all DM pt, bilateral visual loss
All are either reversible or can be managed well
(slow/stop vision loss) if detected early
Therefore, primary care’s role is vital in screening of
chronic eye diseases
Questions?
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Edited by: Steven Schendel, PGY-4
Reviewed by: Drs. Fred Mikelberg, David Maberley, Francis
Law
Contact:
R Tom Liu
rztom.liu@gmail.com