advantage that fast scanning is feasible.advantage that reference arm is not scanned,.tune narrow-width wavelength over entire.Spontaneous emission http//superluminescent_diodes.html Output facet relative to the waveguide, and canīe suppressed further with anti-reflection Narrowing, is suppressed by means of tilting the Structures in the spectrum and/or to spectral Optical feedback, which could lead to theįormation of cavity modes and thus to pronounced Optical feedback, so that no laser action can Junction and an optical waveguide, but lack They are similar to laserĭiodes, containing an electrically driven p-n Superluminescent LEDs) are optoelectronic SLD) Superluminescent diodes (also sometimes Sources based on superluminescence (Acronym 25 nm bandwidth _at_ 800 nm12 mm coherence length.Lateral resolution similar to that in a standard The broader the bandwidth the shorter theĬoherence length and the higher the resolution.Good OCT sources have small coherence length and Interferometry is used to measure small time SpatialResolution 10-30 µm Time resolution Speed of sound 1480 m/sec (in water) Speed of OCT is analogous to ultrasound imaging Uses Polarization Sensitive-OCT (birefringence).spectroscopic OCT (absorption, high speed).Reference beam is used as a coherence gate to interference between the reflected light and the.Based on measurements of the reflected light from.Spatial resolution and large penetration depth Three-dimensional imaging technique with high.Occasionally, patients undergo surgery to prevent worsening of glaucoma.Title: Lecture 23 Optical Coherence Tomography OCT: Basic A different laser procedure is performed for angle-closure glaucoma. Laser trabeculoplasty, a procedure that helps drain fluid from the eye, is another common treatment for open-angle glaucoma. Other eye drop medications for glaucoma include β-blockers, carbonic anhydrase inhibitors, α-agonists, and rho kinase inhibitors. The most commonly used topical eye drops for glaucoma are prostaglandin analogues. Glaucoma is treated with medications or procedures to lower intraocular pressure. Other tests for glaucoma include optical coherence tomography (which takes pictures of the back of the eye) and optic disc photography. This type of glaucoma requires emergency treatment to decrease intraocular pressure and prevent rapid onset of blindness.Įye care professionals diagnose glaucoma with several tests, including measurement of intraocular pressure, visual field testing, dilated eye examination to assess the optic nerve, measurement of corneal thickness, and assessment of the angle in the eye between the iris and cornea. Patients with this type of glaucoma can have periodic visual symptoms, but they are often asymptomatic until the condition worsens, and they develop visual symptoms similar to open-angle glaucoma.Īcute angle-closure glaucoma is caused by acute obstruction of fluid drainage from the eye, leading to blurry vision, halos around lights, eye pain, nausea, vomiting, and rapid vision loss. As the disease progresses, patients can develop problems with peripheral vision and, sometimes, central vision, causing difficulty with reading, walking, and driving.Ĭhronic angle-closure glaucoma is characterized by slow, progressive obstruction of fluid drainage from the eye. Most people with open-angle glaucoma have no symptoms initially. Open-angle glaucoma accounts for more than 90% of cases of glaucoma, and it occurs when fluid in the eye is unable to drain properly. Shared Decision Making and CommunicationĬommon Types of Glaucoma and Their Symptoms.Scientific Discovery and the Future of Medicine. Health Care Economics, Insurance, Payment.Clinical Implications of Basic Neuroscience.Challenges in Clinical Electrocardiography.
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