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The Essentials for Paraoptometric Personnel in Understanding Medical Optometry. Jeff D. Miller, O.D. Stillwater, Oklahoma millereyedoc@cockrelleyecare.com. Baby Boomers. Approximately 80 Million 7,918 people turn 60 each day in 2006 That’s 330/hour
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The Essentials for Paraoptometric Personnel in Understanding Medical Optometry Jeff D. Miller, O.D. Stillwater, Oklahoma millereyedoc@cockrelleyecare.com
Baby Boomers • Approximately 80 Million • 7,918 people turn 60 each day in 2006 • That’s 330/hour • Every day until 2014, 10,000 Americans turn 50 • 1/8 Americans are 65 or older
Health of Americans • Diabetes –epidemic in children • HTN – steep rise • CVD – linked w/HTN • Obesity – 15% in 1980 - 33% in 2004 • Obesity doubles the risk of vision loss AMD, Glaucoma, Cataracts, Diabetes
Ocular Disease -TODAY • Diabetic Retinopathy is the leading cause of blindness ages 25-74 • AMD is the most common cause of blindness in Americans 60 and older • Cataracts are the leading cause of blindness in the world
Ocular Disease-TODAY • Glaucoma – 2.2 million cases diagnosed, 2 million undiagnosed • 1 Million blind, 2.4 million visually impaired (2/3 are female) • By far the most common ocular disorder: “Ocular Surface Disease” or OSD
Ocular Disease EstimatesIn The Year 2020 • NEI Eye Prevention Research Group • Diabetic Retinopathy – 50% increase • AMD – 70% increase • Glaucoma – 3.36 million – 53% increase • Legal Blindness – 70% increase • In 2036 all today’s numbers will double
REMEMBER- OF THE EYE DISEASES WE ARE COVERING TODAY THEY REPRESENT: A. THE LEADING CAUSE OF BLINDNESS IN THE USA AGES 25-74. B. THE LEADING CAUSE OF CENTRAL VISION LOSS IN PATIENTS OVER 60 C. THE SECOND LEADING CAUSE OF PREVENTABLE BLINDNESS IN THE USA (CATARACTS ARE FIRST) AND THERE IS NO WAY TO TELL YOU HAVE THEM BASED ON THE WAY YOU FEEL! THEY ARE ONLY DETECTABLE THROUGH AN EYE HEALTH EVALUATION
GLAUCOMA • Glaucoma is a group of diseases that can damage the eye’s optic nerve and result in irreversible vision loss and blindness. • Glaucoma is multifactorial – it is not a single disease process. Rather it is a large group of disorders. • The term glaucoma should only be used in reference to the entire group of disorders, just as the term cancer is used to encompass many clinical entities with certain common denominators.
GLAUCOMA • The common denominator in glaucoma is optic nerve damage/death which derives from various risk factors. • Glaucoma is the leading cause of preventable blindness in the US. • There are several forms of glaucoma, the most common is Primary Open Angle Glaucoma or POAG.
Forms of Glaucoma • POAG, Primary Open Angle Glaucoma • LTG or NTG, Low Tension or Normotensive Glaucoma • Angle Closure Glaucoma • Congenital Glaucoma • Secondary Glaucoma’s – Pigmentary Glaucoma, Neovascular Glaucoma, and Inflammatory or Uveitic Glaucoma, Angle Recession Glaucoma
Risk Factors for Glaucoma • Intraocular Pressure, IOP • Genetics - Family History • Age (increases after 40yrs and 60 yrs) • Race (African American, Hispanics) • Gender (men or women?) • Diabetes Mellitus • Cardiovascular Disorders • Obstructive Sleep Apnea
Glaucoma Diagnosis • Traditionally: IOP, optic nerve changes, visual field defect – treat or monitor. • Risk factors are better known today and play a large role in treatment initiation. • Today’s technology also allows much earlier diagnosis and treatment initiation through various tests/technology:IOP, stereoscopic optic nerve evaluation, optic nerve topography, nerve fiber layer analysis with scanning lasers and OCT, central corneal thickness, gonioscopy, Visante OCT, blood flow analysis, and visual fields.
Diagnosis • IOP – “normal” 10-22mmHg • Remember LTG or NTG, IOP appears in the normal range • ONH evaluation –characteristic changes • CCT - central corneal thickness obtained via pachymetry - normal is 555 microns • Gonioscopy – evaluates where the aqueous fluid drains • Nerve Fiber layer Analysis: GDx VCC, HRT II and III, OCT (i.e.Stratus,Cirrus) • Visual Fields
ONH EVALUATION Normal Healthy Optic Nerve
EMGTS-patients with exfoliation or recurrent disc hemorrhage may have worse prognosis and need greater tx and closer observation. CNTGS-”strongly predictive of disease progression” OHTS-detection of disc hemorrhages-84% were detected only by photos 16% by exam and photos. Increased risk of glaucoma development found however, 86.7% w/disc hem have not converted to glaucoma.
Key parameters are Horizontal Integrated Rim Volume* and Cup/Disc ratios Yellow line on composite diagram indicates individual radial scan selected and displayed Fundus image for verification of scan placement Optic Nerve Head Analysis Disc edge is determined by the end of the RPE -shown by blue marker *Comparison of three optical coherence tomography scanning areas for detection of glaucomatous damage. Wollstein G, Ishikawa H, Wang J, Beaton SA, Schuman JS. Am J Ophthalmol. 2005 Jan;139(1):39-43
CCT-Central Corneal Thickness • Ultrasound Pachymetry (sound waves) • Visante OCT Pachymetry (light waves) • Ocular Hypertensive Treatment Study OHTS – CCT can suggest/determine risk >588 microns (low risk) =555-588 microns (mod. risk) <555 microns (high risk)
GDx VCC Printout Glaucoma Normal Fundus Image Parameters Thickness Map Deviation Map TSNIT Graph Comparisons of each scan to the Normative Database allows accurate and rapid interpretation in one exam
Correlation of the Deviation Map and Thickness Map with Visual Field Pattern Deviation is shown below These are examples from normal to advanced glaucoma • A normal eye with normal thickness and deviation maps and normal visual field • An eye with focal Retinal Nerve Fiber Layer loss prior to visual field loss • A moderate glaucoma eye with superior RNFL loss and inferior visual field loss • An advanced glaucoma eye with advanced RNFL and visual field loss
Cirrus™HD-OCT Stratus OCT™
Glaucoma – RNFL Thickness Analysis An OU analysis example (2)
VISUAL FIELDS • Helps to confirm a definitive diagnosis of glaucoma. • Determines the degree of vision loss associated with glaucoma. • Helps to monitor the progression of the disease and determine treatment strategies and if the medications and/or surgeries are working.
Treatment – ultimate goal is to lower IOP by reducing the production of the fluid in the eye or increasing the outflow of the fluid (Aqueous) Medical Treatment Topical Glaucoma Drops Various Classes: reduce aqueous production or increase aqueous outflow Neuro-protection (now and future) Blood flow enhancers (future) Timoptic, Betimol, Betagan, Betoptis S, Azopt, Trusopt Travatan, TravatanZ, Lumigan, Xalatan, Alphagan, Alphagan-P, Cosopt, Combigan, Pilocarpine What about oral meds ? (Diamox, Neptazane) Treatment
SurgicalTreatment • Laser treatment: The laser treats the tissue that the aqueous fluid drains through such that it opens or “cleans” it out increasing drainage ALT - Argon Laser Trabeculoplasty SLT - Selective Laser Trabeculoplasty • Other Lasers • Trabeculectomy - creates drainage canal • Glaucoma valve – creates drainage canal
Glaucoma Management • Once diagnosed patients should be monitored on a quarterly basis for IOP and yearly (at minimum) for changes in VF, optic nerve, nerve fiber layer damage and gonioscopy. • The more advanced the more often VF, and other testing should be performed. • Glaucoma suspects should be monitored yearly or on a 6 month basis depending on their findings and other health issues.
GLAUCOMA QUESTIONS ?
MACULAR DEGENERATION • Leading cause of severe irreversible central vision loss and legal blindness in individuals 60 and older in the US. • Predominantly Caucasian (Hispanics on the rise) • Approximately 30% of those over 75 have early AMD • 23% of the remainder of those will develop it with in five years • By 2020 the incidence is estimated to rise by 70% • By 2036 all today’s numbers will double (Baby Boomers)
Macular Degeneration- Two Forms • Non-neovascular, dry or atrophic macular degeneration • Neovascular, wet or exudative macular degeneration
Dry or Atrophic Macular Degeneration-AMD • The retina is 10 layers thick. The last layer is called the RPE - Retinal Pigment Epithelium • The RPE is responsible for providing nourishment to the retinal visual cells and maintains the retinal environment • If the RPE is sick or damaged the retina degenerates • AMD is characterized by abnormalities in the retinal pigment epithelium (RPE) with drusen formation • Drusen are tiny white or yellow accumulations in Bruch’s membrane, a membrane between the final layer of the retina (RPE) and its blood supply in the choriocapillaris.
Wet or Exudative Macular Degeneration • The wet form of AMD is defined by the appearance of “new” blood vessel growth, neovascularization, originating in the layer below the retina called the choricapillaris. • These new blood vessels are abnormal and leak fluid and blood into the subretinal space causing disruption of the RPE with subsequent fibrosis and scarring • The damage to the RPE is irreversible