1 / 25

Introduction to glaucoma

Introduction to glaucoma. From a Clinician’s Standpoint. Readings. Alexander, pp. 258-276 Kanski Perimetry, pp. 24-32 OCT, HRT & GDx, pp. 47-52 Glaucoma, pp. 371-393. Overview. Introduction Diagnosis History and risk factors Tonometry Pachymetry Gonioscopy ONH structure

aysel
Télécharger la présentation

Introduction to glaucoma

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction to glaucoma From a Clinician’s Standpoint

  2. Readings • Alexander, pp. 258-276 • Kanski • Perimetry, pp. 24-32 • OCT, HRT & GDx, pp. 47-52 • Glaucoma, pp. 371-393

  3. Overview • Introduction • Diagnosis • History and risk factors • Tonometry • Pachymetry • Gonioscopy • ONH structure • ONH function • Risk Assessment • Management • Adherence • Communication

  4. Glaucoma introduction • Optometric lifelong learning • Optic nerve head and nerve fiber layer imaging • IOP and pachymetry • Pilocarpine  Timoptic  Xalatan

  5. Diagnosis • History and risk factors • Asymptomatic until late • Age • Race: younger age at diagnosis, increased risk of blindness (African-Americans) • Hispanics especially over the age of 75 • Family history • ? Myopia, Diabetes, hypertension

  6. Diagnosis • Tonometry (IOP) • Goldmann applanation • Single most important risk factor • For development of glaucomatous optic neuropathy • Risk increases with increasing IOP • Vital for initial diagnosis and management • Currently, only major treatable risk factor

  7. Diagnosis • Tonometry (IOP) • Glaucoma may develop at any IOP level • Central corneal thickness data via pachymetry to predict the “true” IOP • More to the story than adjusting for central corneal thickness • Biomechanical influences on the cornea influence the IOP….. • New tonometers: Rechart Ocular Response Analyzer, Pascal tonometer, Icare

  8. Diagnosis Pachymetry Measurement of corneal thickness Normal population mean value: 544 + 34 microns Corneal thickness is a risk factor for IOP independent of its ability to skew IOP Thinner than normal increases risk Can also make adjustment for IOP: most corrections based on values between 2.5-3.5 mm Hg per 50 microns of CCT (central corneal thickness) from 545 microns

  9. Diagnosis • Gonioscopy • Careful exam of anterior chamber angle • My lens of choice • Essential for glaucoma suspects and diagnosis • POAG: Primary Open Angle Glaucoma • Permits exclusion of angle closure and other secondary types of glaucoma

  10. Diagnosis • ONH Structure • Evaluation of the ONH and retinal nerve fiber layer (RNFL) • View the ONH and RNFL • Also ONH and RNFL Imaging: OCT, HRT, GDx • Structural damage prior to VF defects • 50% rule • The BEST way: slit lamp retinal biomicroscopy through a dilated pupil allowing for magnified stereoscopic view • To view the ONH

  11. DIAGNOSIS • ONH Structure • Evaluation of the neuroretinal rim (NRR) • Healthy rim tissue quadrants thickest  thinnest • Inferior • Superior • Nasal • Temporal

  12. DIAGNOSIS • ONH Structure • Focal thinning of the rim tissue or “notch” • Vertical cup elongation • Increased cup depth • Disc asymmetry • Disc hemorrhage • Cup size

  13. DIAGNOSIS • RNFL • Red-free filter view • Better: RNFL Imaging • SLGT: Scanning Laser Glaucoma Test • Standard of Care? To Manage Glaucoma • HRT: Heidelberg Retina Tomograph • Scanning laser tomography for the optic nerve • GDx VCC • Scanning laser polarimetry for the RNFL • OCT: Optical Coherence Tomography • For the optic nerve and RNFL

  14. DIAGNOSIS • Scanning Laser Glaucoma Tests • All have excellent diagnostic performance for early glaucoma • Not meant to be used in isolation

  15. DIAGNOSIS • ONH Function • Measuring the Visual Field (VF) via standard automated perimetry • Humphrey Field Analyzer • Central threshold • 30-2 • 24-2 • SITA

  16. DIAGNOSIS • ONH Function • VF Defects • Reflect damage to NFL bundles as they track toward the optic nerve • ONH appearance should match the VF • Progression of defects: paracentral / nasal step  arcuate • Central vision not affected until late in course

  17. DIAGNOSIS • ONH Function • Additional VF Instruments • FDT (Frequency Doubling Technology) Matrix • SWAP (Short-wavelength automated perimetry) or blue-yellow perimetry • Heidelberg Edge Perimeter

  18. Risk assessment • Who to treat? • When to treat? • What extent to treat? • Currently review results as a whole • Detect any damage • Set target IOP to reduce or eliminate further damage • Monitor every 3 months

  19. Risk Assessment • The STAR Risk calculator • Pfizer, Inc. • Age. IOP, CCT, vertical C/D ratio, pattern standard deviation (PSD) for a HFA II threshold visual field, diabetes status • Takes into account many important trials and studies related to glaucoma

  20. Management • Classes of medical agents • Prostaglandin analogs (Xalatan, Lumigan, Travatan) • Beta-adrenergic antagonists (Timoptic, Betoptic-S) • Carbonic Anhydrase Inhibitors (Trusopt, Azopt) • Adrenergic Agonists (Alphagan-P) • Cholinergic Agonists (Pilocarpine) • What I like to ask in clinic?…..MOA’s, side effects, contraindications, how to write the Rx

  21. MaNAGEMENT • Medical Agents…considerations • How well do they work? (% drop in IOP) • Chances of compliance? • Cost issues? • Prostaglandins have become the primary agents of therapy…others as adjuncts when needed

  22. MANAGEMENT • Laser and surgery • SLT: Selective Laser trabeculoplasty • ALT: Argon Laser trabeculoplasty • Trabeculectomy

  23. MANAGEMENT • Overview of Monitoring $ • Every 3 months • yearly DFE, VF, SLGT • Pachymetry at diagnosis • Photos and gonioscopy every 2 years

  24. Adherence • Nonadherence to topical glaucoma meds • Prevalent • Difficult to detect • Patients must understand progression and be concerned about future consequences of glaucoma • Active learners and participants tend to adhere better

  25. Communication…a few suggestions • 1. Tell me how you have been taking your medications? • 2. Tell patient you will not be judgemental regarding non-adherence • 3. Explain how information about adherence will affect treatment decisions • 4. Ask about forgetting or missing medications • 5. non-adherent…tell me what you understand about glaucoma and what your concerns are

More Related