Glaucoma Diagnosis. Definition of Glaucoma. Diagnosing Glaucoma. Vision Institute Annual Fall Conference

Transcription

1 Glaucoma Diagnosis Vision Institute Annual Fall Conference Mitchell W. Dul, OD, MS, FAAO Richard J. Madonna, MA, OD, FAAO Definition of Glaucoma Glaucoma can be regarded as a group of diseases that have as a common end point a characteristic optic neuropathy which is determined by both structural change and functional deficit. World Health Organization Diagnosing Glaucoma Risk factors IOP Gonioscopy Structural assessment Functional Assessment 1

2 Variability in IOP Measurement Normal short term and long term IOP fluctuation Inherent intra and inter examiner measurement variability Instrument calibration 2

3 Indications for Gonioscopy Visualization of the anterior chamber angle Assessment of the narrow angle Classification of glaucoma Specific conditions assessed Angle closure: history of, risk of, presence of PAS Iris/angle neovascularization Trauma/angle recession Neoplasia Pigmentation: PDS, ES Congenital anomalies Foreign bodies 7 Angle Anatomy 8 UBM and AS OCT 9 3

4 Assessment of the Optic Disc in Glaucoma 1. Observe the scleral Ring to identify the limits of the optic disc and its size. 2. Identify the size of the Rim. 3. Examine the Retinal nerve fiber layer. 4. Examine the Region of parapapillary atrophy. 5. Look for Retinal and optic disc hemorrhages. Stereoscopic Disc Examination Gold Standard when performed by an experienced examiner Limitations Intra and inter observer variability Poor reproducibility Bias Fundus Photography Eliminates some of the sources of variability and bias Excellent at finding disc hemorrhages and RNFL defects 4

5 Optic Disc Hemorrhage Standardization Baseline Normative data Progression Quantitative Imaging 5

6 What is the Clinical Utility of Measuring the Macular Ganglion Cells Earlier recognition of the disease? Everyone? Some patients? Which ones? Vs. Duplicative same information from measuring circumpapillary RNFL? Figure 7 Venn diagrams showing the overlap between abnormal nerve fiber layer (NFL) and ganglion cell complex (GCC) thicknesses in both perimetric glaucoma (PG) and preperimetric glaucoma (PPG) groups. Abnormalities were detected at the 5 percentile level... Ou Tan, Vikas Chopra, Ake Tzu Hui Lu, Joel S. Schuman, Hiroshi Ishikawa, Gadi Wollstein, Rohit Varma, Davi... Detection of Macular Ganglion Cell Loss in Glaucoma by Fourier Domain Optical Coherence Tomography Ophthalmology Volume 116, Issue e2 Figure 3 The areas under the curve (AUCs) of the receiver operating characteristics of the best 5 ganglion cell?inner plexiform layer (GCIPL) parameters (A), best GCIPL, best retinal nerve fiber layer (RNFL), and best optic nerve head (ONH) parameters fo... Jean Claude Mwanza, Mary K. Durbin, Donald L. Budenz, Fouad E. Sayyad, Robert T. Chang, Arvind Neelakantan,... Glaucoma Diagnostic Accuracy of Ganglion Cell?Inner Plexiform Layer Thickness: Comparison with Nerve Fiber Layer and Optic Nerve Head Ophthalmology Volume 119, Issue

7 Is Disease Present? Glaucomatous Field Defects Peripheral defects Central defects Generalized depression Blind spot enlargement Temporal defects Nerve fiber layer defects 7

8 What We Would Like to See The Clinical Dilemma Patients with the same degree of NRR loss can have different amounts of visual field loss. Some patients with GON do not have VF loss. Some patients with VF loss seem to have no structural correlate. How then does a clinician utilize structural and functional data in patient care? Structure or Function Consensus Statement In different cases, either structural examination or functional testing may provide more definitive evidence of glaucoma, so both are needed for detection and confirmation of the subtle early stages of the disease. Consensus Statement produced at the First International Meeting of the Association of International Glaucoma Societies,