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Etiology And Evaluation Of ARMD. Thomas J. Landgraf, O.D., F.A.A.O. Clinical Associate Professor, UMSL College of Optometry. Introduction. My Background Goals / Course Objectives Sources Clinical Ophthalmology : Kanski Primary Care of the Posterior Segment : Alexander
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Etiology And Evaluation Of ARMD Thomas J. Landgraf, O.D., F.A.A.O. Clinical Associate Professor, UMSL College of Optometry
Introduction • My Background • Goals / Course Objectives • Sources • Clinical Ophthalmology: Kanski • Primary Care of the Posterior Segment: Alexander • Clinical Ocular Pharmacology: Bartlett & Jaanus • Review of Optometry / Ophthalmology: on-line and annual handbooks • OCT of Ocular Disease: Schuman, Puliaftio, Fujimoto • Questions?: landgraft@umsl.edu
Introduction • One more source • From Review of Optometry • Optometric Study Center: August 2007 • AMD Gets A New Image • Shechtman, Reynolds, Pizzimenti
Case #1 • S: • 89 yo Caucasian female • Aricept, Lexapro, HCTZ, Ocuvite • Cataract sx OU 12 years prior • Family hx: cataract, glaucoma, arthritis, cancer, leukemia • Non-smoker • F/U on ARMD dry OD, wet OS and dry eye syndrome OU
Case #1 • S: About the ARMD • 11 years • Constant duration • No changes in vision • Uses Home Amsler daily with compliance
Case #1 • O: • BVA OD: 20/40, OS HM@ 3 ft • PERRL without APD, FROM, FTFC OU • Amsler: negative scotoma, metamorphopsia OD, positive metamorphopsia OS • SLX: dermatochalasis, collarettes, arcus, PCIOL, syneresis • T(a): 16, 15 at 3:12 pm • Trial frame refraction: no change OU
Case #1 • O: DFE with 20 and 90 D lenses • ONH normal, .4 rd OU • Macula / posterior pole: drusen OD, scarring, fibrosis, and pigmentary changes OS • Normal periphery OU
Case #1 • A: • ARMD OU stable, OD dry, OS wet • Pseudophakia OU • Dry Eye Syndrome OU
Case #1 • P: • To monitor, fundus photos today, RTC 6 months • To monitor • Continue artificial tear regimen
Case #1 • Considerations: etiology and diagnosis • Risk factors? • Why no OCT? • Foresee PHP or QuantiFEYE? • Fluorescein angiography? • Home amsler? • Nutritional modifications? • Referral to retinal specialist
ARMD • Getting Started • ARM vs ARMD • Non-neovascular vs dry vs non-exudative vs atrophic • Neovascular vs wet vs exudative
ARMD • The numbers • Leading cause of blindness in the elderly in the US • 8 million in the US: numbers vary and increasing • Visual impairment in about 1.7 million over age 65 • 90% with non-neovascular form
Etiology of ARMD • Poorly understood • Multifactorial • Genetic predisposition • Environmental
Etiology of ARMD • Progression more understood • Drusen signify development risk • Small large drusen • Consider number and size, unilateral or bilateral • Pigmentary changes signify development risk
Etiology of ARMD • Risk Factors: nonmodifiable • Age • Race: Caucasian • Genetics: postive family history • Sex: female • Cataract: NS, surgery and progression? • ARM associated with soft drusen • Low Macular Protective Pigment Density (MPPD)
Etiology of ARMD • Risk Factors: modifiable • Cigarette smoking • Dietary habits • Physical activity and cardiovascular health • Macula is hemodynamically active • HTN, DM, hyperlipidemia, obesity
Etiology of ARMD • Ocular Risk Factors for Progression • AREDS Study • 1 risk factor per presence of large soft drusen in each eye • 1 risk factor for any pigment abnormality in each eye • 1 risk factor for intermediate drusen in both eyes • 5 year risk of developing advanced AMD • 0 factors: 1.5% • 1 factor: 3% • 2 factors: 12% • 3 factors: 25% • 4 factors: 50%
Etiology of ARMD • Ocular Risk Factors for Progression • Macular Photocoagulation Study Group • Ocular risk factors for development of CNV (choroidal neovascularization) in fellow eye when opposite eye has CNV • Risk factors: 5 or more drusen, focal hyperpigmentation, 1 or more large drusen, systemic hypertension • 5 year incidence rate for development of CNV: 7% (0 risk factors) 87% (4 risk factors)
Etiology of ARMD • Risk Factors: Primary Care O.D. Considerations • Behavior modification • Optometric recommendations • Diet, physical activity, smoking, cardiovascular health • Keep doing what we do best • Optometrists take the time • Explanation, Education, and Answering Questions
Etiology of ARMD • VEGF • Vascular Endothelial Growth Factor • Protein mediator of CNV • Pro-inflammatory, causes pathologic angiogenesis, increases vascular permeability • Needed normally for angiogenesis, neuroprotection, healing promotion
Etiology of ARMD • VEGF • Realized as treatment target • Elevated levels in CNV taken from patients with AMD • Treatment ideally must rid abnormal vessels and spare normal ones • Additional treatment targets • Lucentis, Avastin are examples • Anti-VEGF agents
Diagnosis of ARMD • Bottom Line For O.D.’s • Early detection greatly aids all treatment modalities • Increases prognosis to preserve vision • Advances in retinal technology have allowed for early detection and treatment • Majority of patients • Significant decrease in VA • At time of CNV diagnois
Diagnosis of ARMD • Overview • Ophthalmoscopy, BIO, retinal biomicroscopy, photos, and amsler grid • OCT (Optical Coherence Tomography) • Foresee PHP (Preferential Hyperacuity Perimetry) • Fluorescein Angiography (FA) and Indocyanine Green (ICG) Angiography • QuantifEYE
Diagnosis of ARMD • Characteristics (ophthalmoscopy) • Pathologic deterioration of RPE, Bruch’s, and choriocapillaris • Overlying sensory retinal damage • Decreased visual function
Diagnosis of ARMD • Forms (ophthalmoscopy) • Nonexudative • Increased prevalence vs exudative • Drusen and RPE alteration
Diagnosis of ARMD • Forms (ophthalmoscopy) • Exudative • Only 10-20% of AMD cases • Majority of severe vision loss • CNV membrane • Single most important feature associated with post-treatment prognosis (TAP: Treatment of AMD with Photodynamic Therapy Trial) • Subretinal leakage, edema, and hemorrhage • Neurosensory retina damage • Fibrovascular scar formation with irreversible severe vision loss
Diagnosis of ARMD • OCT for macular disease • Non-invasive, non-contact imaging • Low coherence laser interferometry • Construct cross-sectional image of retina • Visualization of the major retinal layers
Diagnosis of ARMD • OCT • Bright image colors: high optical reflectivity • Dim colors: minimal reflectivity • Calculates retinal thickness maps and charts • From 6 radial lines, which all intersect through the fovea • Distance between internal limiting membrane / NFL and RPE
Diagnosis of ARMD • OCT • Expands potential vs FLAN to better manage AMD • Vs FLAN • > 37,000 US OCT’s daily with decrease in # of FLAN’s • Cost and complications • Structural information regarding RPE atrophy, CNV, and retinal edema • Limitations: poor tear layer, cataract, dirty lens instrument, lateral eye movement • Dilation?
Diagnosis of ARMD • OCT • Categorizing wet AMD • Classic CNV membrane • Poorly defined CNV membrane • Retinal thickness • Increases in retinal thickness: CNV, neurosensory or RPE detachment • Decreases in retinal thickness following CNV treatment • Optimized retreatment protocols: anti-VEGF therapy
Diagnosis of ARMD • OCT and wet AMD • Structural changes with wet AMD • May develop prior to visual changes or ophthalmic signs • Early diagnosis and timely referral for treatment
Diagnosis of ARMD • Foresee Preferential Hyperacuity Perimetry (PHP) • Indication: diagnostic aid for detection and monitoring of the progression of ARMD, but not limited to, the detection of CNV • Non-invasive visual field analyzer
Diagnosis of ARMD • PHP • Background • Amsler grid: used for evaluation and self-monitoring • Less than effective in early detection of CNV • Problems with patient fixation and noncompliance • Patients unaware of small or central defects
Diagnosis of ARMD • PHP • To address problems with amsler • Quantifies and maps central defects associated with CNV in AMD • 500 data points • Central 14 degrees of VF
Diagnosis of ARMD • PHP • Mapping via touch screen to indentify flashing dots • Like Humphrey VF perimetry, but uses hyperacuity (eye’s ability to detect subtle, relative spatial localization of two objects) • Linear signals perceived as distorted or misaligned • 10 x more sensitive than Snellen • Can detect RPE elevation and shift of photoreceptors in AMD which occurs with drusen and CNV
Diagnosis of ARMD • PHP: how it works • Series of dot deviation signals flashed at predefined intervals • Projection of dot deviation signal on retinal lesion: distortion, scotoma and/or blurring of part of line • Patient touches any deviations in signals with stylus • Artificial distortions aid quantification and reliability • Patient’s responses recorded and analyzed
Diagnosis of ARMD • PHP Report • 1. Hyperacuity deviation map • 2. Hyperacuity defect zones table • 3. Results • Reliability indices • Test reliability • Baseline exam • 4. Examination • History chart • 5. Comments
Diagnosis of ARMD • PHP: The Stats • Provides reliability indices to indicate if defect outside normal limits • Good specificity in differentiating CNV from intermediate dry AMD • Good sensitivity in detecting newly diagnosed CNV (82% sensitivity, 88% specificity) • Statistically significant correlation with with stereo-fundus photography and fluorescein angiography
Diagnosis of ARMD • PHP • Advantages • Non-invasive • Cost-effective • Monitor with reproducible quantitative measurements • Disadvantages • Difficult for elderly patients with poor manual dexterity • False-positive and negative readings • Not good for geographic atrophy, less than 20/200, previous diagnosis of wet AMD
Diagnosis of ARMD • PHP: benefits per Foresee • Structured tutorial • Technician free test operation • Easy to use by patient • Test history presentation for long term tracking • Rapid testing: about 5 minutes per eye • Ergonomically improved
Diagnosis of ARMD • PHP • Every 3-4 months after intermediate dry AMD diagnosis • 20% of dry AMD CNV (5 years) • Every 6-12 months after early dry AMD diagnosis • Early detection of CNV lesion in asymptomatic patient without amsler grid defects • Billed as 92082 (perimetry) • Practice with 100 dry AMD patients, return on investment in < 1 year
Diagnosis of ARMD • Fluorescein Angiography (FA) • Best method for evaluating CNV membrane • Current guidelines for therapeutic intervention of wet AMD • Mandated by findings observed on FA • Defines location and characteristics of CNV membrane • Extrafoveal or subfoveal • Classic, occult or combination
Diagnosis of ARMD • FA • Classic CNV membrane • Lacy and hyperfluorescent early • Intensified leakage later • Occult CNV membrane • Less leakage • Indistinct boundaries • Irregular hyperfluorescence later • Retina hemorrhages obscure
Diagnosis of ARMD • ICG (Indocyanine Green) Angiography • Background • Indications: occult CNV • Side effects and contraindications