Glaucoma：青光眼.pptVIP

Glaucoma Glaucoma An optic neuropathy characterized by: Elevated intraocular pressure Optic disk cupping Visual field loss Normal visual field Shrinking vision Advanced field loss Tunnel vision Raised intraocular pressure Physiology of the Aqueous Humor Aqueous formation and flow Ciliary body Posterior chamber Pupil Anterior chamber Trabecular meshwork Schlemm’s canal Pathophysiology Risk Factors for developing Glaucoma Age (40 years old) Females Males Hyperope (+) Family history of glaucoma GIC1a (myocillin gene) in open angle gl Systemic disease: HPN, DM Trauma Underlying ocular conditions: ex. CRAO, phacolytic, uveitis Drugs, ex. steroids Clinical Assessment Fundoscopy / Optic Disc Assessment Tonometry Gonioscopy Visual Field Evaluation Optic Disk Assessment Physiologic Cup Normal central depression Size depends on the bulk of the fibers that form the optic nerve relative to the size of the scleral opening Hyperopic eyes – scleral opening is small - small optic cup Optic Disk Assessment Glaucomatous optic atrophy Loss of disc substance; enlargement of optic disc cup Disc pallor in the area of cupping Concentric enlargement of the optic cup or preferential superior and inferior cupping with focal notching of the rim of the optic disc Retinal vessels on disc are displaced nasally “bean pot cup” Cup-disc ratio: ratio of cup size to disc diameter (0.5 or significant asymmetry between the two eyes) Atrophy of nerve fiber layer (Hoyt’s sign) Optic Disc Cupping: Tonometry Measurement of intraocular pressure (IOP) Normal pressure = 10-24 mmHg Types of Tonometry Goldmann Applanation Tonometer – measures the force required to flatten a fixed area of the cornea, gold standard Perkins Tono Pen – portable Pneumomatotonometer – irregular surface cornea Schiotz – portable, measure corneal indentation produced by known weight Applanation Tonometry Gonioscopy Clinical technique used to examine structures in the anterior chamber 4 structures: Schwalbe’s l