age related macular degeneration from optometrist point of view
DESCRIPTION
ARMDTRANSCRIPT
PRESENTED BY:
ANIS SUZANNA BINTI MOHAMADOptometrist and Contact Lens Consultant
B.Sc (Hons) Optometry UKM
Healthy retina
ANATOMY OF RETINA
AGE RELATED MACULAR DEGENARATION
• Definition:– A DEGENERATIVE eye disease that AFFECT
MACULA– which responsible to the central vision
• Types of ARMD– Early stage– Late stage
• Dry ARMD• Wet ARMD
• Bruch membrane become less permeable– Blocks nutrition from RPE, prevent waste product from
retina escaping• The quality of retina deteriorate (dry armd)• New blood vessel are stimulated into retina to clear away
the waste products (wet armd)
Early stage ARMDSIGN• Drusen
– Discrete yellow spot at macula– The accumulation occurs as bruch's membrane
becomes thicker• prevents the free flow of materials to and from
photoreceptors layer. – Also, the retinal pigment cells accumulate
lipofuscin. • This pigment will also slow down the passage of
chemicals to and from the retina.
SYMPTOM• Usually has normal vision• Difficult driving, recognizing dimly road sign– Loss of rod photoreceptors (earlier than cones)
Late stage: DRY ARMD• Slowly progressive atrophy of
photoreceptor, RPE, and choriocappilaries• Tissue has thinned and lost pigment
• Also known as atrophic AMD, nonexudatives AMD, nonvascular AMD
• Progress over month, years
• Bilateral– Severity and progress may
different between BE
• SIGN– Usually assoc with hard
drusen• Small, round, discrete, yellow
white spot asocc with focal disfunction of RPE
– Atrophy of RPE
– Enlargement of atrophic area, pre-existing drusen appear, choroidal vessel visible geographic atrophy
Geographic atrophy
Dry ARMD
• SYMPTOM– Slow and progressive loss central vision• Called central scotoma
– Vision distorted• Called metamhorphopsia• Drusen has expand and increase in no.
Late stage: Wet ARMD• New blood vessel growth
underneath the retina
• body's misguided way of attempting to create a new network of blood vessels – to supply more nutrients
and oxygen to the retina.
• Called choroidal neovascularization (CNV)– leak fluid under the macula– then form scar tissue
leading to central vision loss.
• Also known as exudatives AMD, neovascular AMD
Sign • Soft drusen appear
– Larger and have indistinct margin– May slowly enlarged and coalesce to form solid
drusenoid detachment of RPE
• area of the macula is elevated by subretinal fluid or blood, often associated clumps of exudates
Soft drusen in wet ARMD Wet ARMD or neovascular ARMD
• Symptom
– Profound central vision impairment• Sudden decrease (weeks)
– Vision distorted
Risk factors
1. Aging2. Smoking3. Obesity and inactivity4. High blood pressure5. hereditary
Complications of ARMD1. Decreased contrast sensitivity2. Decreased visual acuity3. Metamorphopsia4. Central scotoma
Decreased contrast sensitivity
– It occurs at early phase of onset.
– The macular at this stage has discrete yellow spots or drusen.
– The hyperpigmentation of RPE can decreased contrast sensitivity of the eye.
Decreased visual acuity – Common in late
stage.– It is due to slowly
progressive atrophy of photoreceptors, RPE and choriocapillaries.
– RPE detachment can occur.
– The gradual vision impairment occurs gradually over months or years.
– Normally both eye is affected but asymmetry.
Metamorphopsia
• It occurs due to thickened Bruch membrane of the eye.
• It may cause unilateral metamorphosia and lead to impairment of central vision.
Patient complains of all the object seen smaller than actual size. (micropsia)
Central scotoma– It occurs when the
foveal area is affected.
– The scotoma, or central blind spot, can be due to geographic atrophy or to the damage of photoreceptor cells from choroidal neovascularization (leaking blood vessels).
Patient complaints of difficult to recognize the face
Clinical manifestations of age-related macular Clinical manifestations of age-related macular degeneration degeneration
Phase Clinical manifestation Associated visual defect
Early stage
Focal drusenIrregular pigmentations of the retinal pigment epithelium
Good visual functionAbnormal dark adaptationReading problem in dark roomBlue-yellow defectDriving car at night is impaired
Late stage
Detachment of the retinal pigment epitheliumRip in the retinal pigment epitheliumChoroidal neovascularizationDisciform scarGeographic atrophy of the RPE
Decreased visual acuity
MetamorphopsiaCentral scotoma
EARLY DETECTION OF ARMD
• Purposes: – To monitor the progression of the sign of
small drusen form in the macula.– Can give appropriate management to the
patient according to their stage. – To prevent the dry ARMD progression from
develop into the wet ARMD.–Wet ARMD is progresses much more quickly
and can cause severe damage of vision.
Spontaneous modifications of drusen
Drusen Drusen
Choroidal neovascularizationChoroidal neovascularization
RPE detachmentRPE detachment
Geographic atrophyGeographic atrophy
Disciform scarDisciform scar
ASSESSMENT OF AGE-RELATED MACULAR DEGENERATION
Patient’s History• Purpose:
– A careful review of the patient’s family history can help differentiate the ARMD or the other macula associated disease.
• Questions:– Chief complaint
• Ask patient about chief complaint carefully.- onset and course of symptom.
– Symptoms • Ask patient whether they have see object blurred or distorted.• Ask patient if they notice any missing part or wavy of a straight
line.• Ask about glaring problems especially when driving at night,
early morning or early-evening hours
– Ocular history– Medications and allergies– Family History
• Any family members have the ARMD disease?
Ocular Examination• Visual acuity
– Pinhole visual acuity test• Contrast sensitivity
– loss of contrast sensitivity at high spatial frequencies
– loss of peak contrast sensitivity with increasing drusen severity
• Pupillary responses – To differentiate the central scotoma due to optic
nerve disease or macular disease• Biomicroscopy
– to examine other factor that contribute to disability glare
• Color Vision- For screening and diagnosis of color vision
defect on the ARMD patient.
Visual acuity• At early onset of the disease, visual acuity will be
slightly decreased. (VA=<6/9)• Pinhole visual acuity must be done at distance with
habitual correction.
The expected findings:• If the patient decreased visual
acuity due to pathological
disease such as ARMD, pinhole
visual acuity is no improvement
and possibly a further decrease
will occur.
• A refraction should improve
acuity level of the patient at
least to the level obtained
through the pinhole.
Contrast sensitivity• Patient with ARMD is often complaint of
blurring at distance, difficulties to see face and road signboard due to decreased in contrast sensitivity.
• Contrast sensitivity reduced when there are changes happened on RPE.
• Test for contrast sensitivity must be done in order to see the severity of the morphological changes at the macular.
• Expected findings:– Patient with ARMD usually demonstrates
profound loss of acuity on contrast sensitivity test.
Contrast sensitivity can be measured with the use of a contrast sensitivity chart (A) or neutral density
filters (B).
(A) (B)
Color Vision• Color vision test:
– Clinical screening: Ishihara plate.– Diagnosis: D-15 Color Test or FM 100 Hue Test
• Purpose: – To detect the color vision defect that occur in
ARMD patient either red –green or blue-yellow defect.
– To classified as congenital or acquired color defect.
• Expected findings:– Most of the ARMD patient suffered yellow-blue
defect.– But patient must be differentiate with other
macular disease such as diabetic retinopathy.
Supplemental testing• Visual Field – Facial Amsler – Amsler grid– Goldmann perimetry– Automated Perimetry
• All Fundus Related Procedures• Fundus Biomicroscopy• Fundus photography• Opthalmoscopy• Fundus Fluorescein angiography• Optical coherence tomography (OCT)
Visual FieldThere are number of different ways to evaluate the visual field of age-related macula degeneration patient. These include:
1.Facial Amsler2.Amsler grid3.Goldmann perimetry4.Automated Perimetry
No one type of visual field is good for all situations.
Facial Amsler• Purpose:
– It is very useful for patient with cognitive impairment.
– Detect gross monocular visual field of the patient.
• The central visual field can then be tested by
asking the patient to report any defects in your
facial features while they look toward your nose.
Simultaneously present targets
• Purpose:– Alternative method to get grossly detection of patient’s
visual field– Patient have to report the existence of the object that
shown.– Each of the object held in different visual quadrant.
Amsler Grid• Purpose:
– It can give useful information regarding central scotoma, areas of missing, blurred, or distorted lines.
– It is sensitive to small scotoma within central 10° of visual field.
– The test is also useful for differentiating neuro-ophthalmic and macular disease.
Patient experienced deep dark spot at the center of the Amsler Grid
• Instruction:1. Hold the chart at a reading
distance of 30 cm; adequate and even lighting is important.
2. You should wear your fully prescribed spectacles and for elderly, their reading glasses, during the test.
3. Cover the left eye, and use your right eye to focus on the center dot.
4. If patient difficult to see the white dot at the center, ask them to imagine the intersect of the two line at the center.
5. Ask patient: Do you notice any wavy, broken or distorted lines or blurred or missing areas of vision within the chart?
6. Repeated the above examining on your left eye.
It is a 10 x 10 cm square grid formed by multiple white lines on a black background and with a white dot at the center.
Goldmann perimetry
• Advantages:– Ability to
directly monitor patient attention
– Present custom test points
– Test the complete visual field.
Large central scotoma seen with Goldmann perimetry test.
Automated perimetry• It is difficult to do with
patient ARMD because they reduced in contrast sensitivity.
• The test can be done on short-wavelength automated perimetry.
• If possible to be done, the result is very useful especially in detecting presence of the central scotoma in advanced cases of ARMD. Automated visual field machines
allows standardized testing and statistical analysis .
All Fundus Related Procedures
I. Opthalmoscopy– Direct– Indirect
II. Fundus photographyIII.Fundus BiomicroscopyIV. Fundus Fluorescein
angiographyV. Optical coherence tomography
(OCT)
Fundus Related Examinations
• Purpose:– To see fundus and macula for both eyes.
• Clinical findings:Clinical features
Signs
Hard drusen(nodular)
Small, round, discrete, yellow-white lesions, and usually located at the macula.
Soft drusen(Exudative)
Larger lesions with ill-defined edges associated with exudative ARMD.
Non-exudative ARMD
Hyperplastic changes of RPE associated with slowly progressive degeneration of the overlying neuroretina and underlying choriocapillaries.
Exudative ARMD
Present with elevated macular area with subretinal fluid or blood associated with clumps of exudates. If the lesion recover, it will leave with subretinal ‘disciform’ scarring.
Fundus Fluorescein Angiography
• Purposes:– To see the leakage of the blood vessels
around the macula.– The test is done to help the doctor confirm a
diagnosis, to provide guidelines for treatment, and to keep a permanent record of the vessels at the back of the eye.
– This test carry out mostly in cases of advanced cases of ARMD for further treatment.
Procedure:• Pupil dilated with the
mydriatics drop before the florescein injected into the body.
• Fluorescein dye injected into bloodstream via hand or arm.
• Following the injection, the fundus photo are taken quickly within 60 seconds during dye enters blood vessels at the back of the eyes. Fluorescein Angiogram of ARMD
Optical coherence tomography (OCT)
– It useful in detecting small changes in retinal thickness, subretinal and sub-RPE fluid and choroidal neovascularization in ARMD.
– It also useful to monitor response to therapeutic intervention.
PREVENTION
• Using the Amsler grid may help detect subtle changes in vision
• A healthy lifestyle helps to prevent ARMD- Stop smoking- Regular exercise
- Reduce risk by 70%- Keep your blood pressure low
- Salt and more than 2 units of alcohol a day may cause BP to rise
- Avoid obesity- Take a balanced diet
- Fruit and vegetables- prevent 36-50% of ARMD- Oily fish twice a week reduces ARMD by 40%
- Vitamin supplementsEg. Antioxidants plus zinc
• Protect eyes from sun exposure with sunglasses
Management
1. Basic Treatment2. Available Treatment Options3. Patient Education4. Prognosis and Follow up
Basic Treatment
• There is NO CURE • T(x) : - slow the progression of disease - prevent the vision loss• Wet AMD : - a lot of treatments are available - mainly for stopping the growth of new blood vessels - if delayed t(x), scar formation
• Dry AMD: - no treatment available - does not involve new blood vessels growing - Low vision aids may be helpful
Treatment of Wet ARMD
1. Anti-VEGF treatment- The most recent treatment- Use anti-vascular endothelial growth factor
(anti-VEGF) drug such as Lucentis, Macugen, Avastin
- Injects into the eyeball (IV) under local anaesthetic
- Cause constriction and closure of the leaking blood vessels
- Prevent further damage of vision
Cont.. Begins with a course of three monthly
injections Monitor every months High success rate Most effective when treating blood vessels
that are ‘active’ or ‘leaking’ Stop sight getting worse Improvement of vision- 40% Complication: IOP, RD, eye infections
2. Photodynamic Therapy (PDT)
• A type of laser t(x)• Use a combination of a light sensitive drug
(Verteporfin) and a low energy (non -thermal) laser
• To stop new blood vessels growing• Adv: the ability to selectively damage tissue• Indication: classic CNV-subfoveal type• SE: transient decrease in vision, sensitivity to
bright light for 24-48 hours.
Classic sub-foveal CNV-Most people with neovascular ARMD have CNV in the centre of the retina
- Regular laser cannot be used as it would destroy the central vision
-Thus, photodynamic laser (PDT) is used.
-But still causing some vision loss
Yellow spot: fovea
Red area: CNV
Classic extra-foveal CNV
-CNV are not in the centre of fovea
-Can be treated by regular laser therapy
-Argon Laser Photocoagulation. High-energy laser light - used to destroy actively growing abnormal blood vessels
Photodynamic Therapy (PDT)
a) Small dirty grey lesion at the fovea surrounded by blood
b) Fundus Angiography venous phase shows hyperfluorescence from classic subfoveal CNV surrounded by a hypofluorescent ring
Photodynamic Therapy (PDT)
c) measurement of greatest linear dimension of the lesion;
d) FA 3 months following successful treatment shows hypofluorescence of the lesion
(Courtesy of S Milewski)
3. Anti-angiogenic drug - Used to slow down or prevent the growth of
the abnormal blood vessels within the eye- Eg. Intravitreal steroid (triamcinolone
acetonide)- SE: ocular hypertension, cataract
- Submacular: removal of the subfoveal CNV- Macular translocation: is aimed at surgically
moving the fovea away from the CNV
4. Surgery
5. Vitamin Supplements• Age-Related Eye Disease Study (AREDS) showed
that for certain individuals, antioxidants such as– 500 g of vitamin C – 400 IU of Vitamin E– 15 mg of beta-carotene – 80 mg of Zinc oxide– 2 mg of Copper
• can decrease the risk of vision loss in patients with intermediate to advanced dry age-related macular degeneration.
6. Refractive correction or low vision aids• Prescribe and increasing near addition for
reduced acuity in patient with macular degeneration
• Other options:- Telescope- Hand magnifiers- Enlarged size print- Enlarged screen size for television or computer
screen- Closed-circuit television (CCTV) or computer
magnification system
Advice for ARMD patient• Consume fruit on daily basis and quit smoking• Exercise regularly• Monitor vision- regular eye examination• Adapt to low vision- eg.making changes to
lighting, using contrast in objects that often used such as door frames and light switches, do labeling and marking medicines and food, and getting rid of potential hazards.
• Counseling, rehabilitation, and training can help with managing household, cooking, shopping, personal grooming and others.
• Develop a personal support network-deal with fear and anxiety-maintain quality of life
Prognosis and Follow up• Dry ARMD:- slow progression- keep most of the vision- may develop the wet form- pt should monitor vision
daily-KIV annually- attend to clinic immediately if signs of reduced
vision or distortion are noted.• Wet ARMD and have had laser treatment: - can be recur-should test vision to see if any blind
spots grow bigger or if any new blind spots appear.- New blood vessels can emerge months or years after
have had successful laser treatment.• If only one eye is affected: - A regular eye examination on the other eye is
needed to discover any sign of new problems.
Summary• ARMD is the most common cause of irreversible vision
loss in people over 50 years of age in Western countries.• 2 types of ARMD: a) Dry and b) Wet• Currently no other t(x) is available for dry ARMD except
of visual aids and lifestyle advice.• Early detection is critical for successful t(x) of wet
ARMD.• Consultation is very important – to cope with low vision • Rehabilitation and training can make their living with
low vision more easier and safer.
References• Jack J Kanski. 2007. Kanski Clinical Ophthalmology 6thedition: Butterworth-
Heinemann• Adrian S Bruce. 2008. Posterior Eye Disease and Glaucoma A-Z : Butterworth-
Heinemann• Theodore Grosvenor. 2007. Primary Care Optometry. Fifth Edition. St. Louis,
Missouri: Butterworth-Heinemann.• http://www.goodhope.org.uk/departments/eyedept/armdwet.htm
(9.00a.m,20/2/2011)• http://www.webrn-maculardegeneration.com/central-scotoma.html(10.00 a.m,
22/2/2011)• http://www.mdsupport.org/library/angio.html (11.00 a.m,21/2/11).• http://www.myvisiontest.com/newsarchive.php?id=1219 (10.00 a.m, 22/2/2011)• http://bjo.bmj.com/content/85/12/1432.abstract(10.00 a.m, 22/2/2011