Coherence theory: In physics, coherence theory is the study of optical effects arising from partially coherent light and radio sources. Partially coherent sources are sources where the coherence time or coherence length are limited by bandwidth, by thermal noise, or by other effect.Dense artery sign: In medicine, the dense artery sign or hyperdense artery sign is a radiologic sign seen on computer tomography (CT) scans suggestive of early ischemic stroke. In earlier studies of medical imaging in patients with strokes, it was the earliest sign of ischemic stroke in a significant minority of cases.Electrical impedance tomography: Electrical Impedance Tomography (EIT) is a non-invasive medical imaging technique in which an image of the conductivity or permittivity of part of the body is inferred from surface electrode measurements. Electrical conductivity depends on free ion content and differs considerably between various biological tissues (absolute EIT) or different functional states of one and the same tissue or organ (relative or functional EIT).Nerve fiber layer: The retinal nerve fiber layer (nerve fiber layer, stratum opticum, RNFL) is formed by the expansion of the fibers of the optic nerve; it is thickest near the porus opticus, gradually diminishing toward the ora serrata.Optic disc: The optic disc or optic nerve head is the point of exit for ganglion cell axons leaving the eye. BecauseLogMAR chart: A LogMAR chart comprises rows of letters and is used by ophthalmologists and vision scientists to estimate visual acuity. This chart was developed at the National Vision Research Institute of Australia in 1976, and is designed to enable a more accurate estimate of acuity as compared to other charts (e.Macular edemaRetinal regeneration: Retinal regeneration deals with restoring retinal function to vertebrates so impaired.Angle-resolved low-coherence interferometry: Angle-resolved low-coherence interferometry (a/LCI) is an emerging biomedical imaging technology which uses the properties of scattered light to measure the average size of cell structures, including cell nuclei. The technology shows promise as a clinical tool for in situ detection of dysplatic, or precancerous tissue.Purtscher's retinopathy: Purtscher's retinopathy is a disease where part of the eye (retina) is damaged. Usually associated with severe head injuries, it may also occur with other types of trauma, such as long bone fractures, or with several non-traumatic systemic diseases.Fourier operator: The Fourier operator is the kernel of the Fredholm integral of the first kind that defines the continuous Fourier transform.Scanning laser ophthalmoscopyGlossmeter: A glossmeter (also gloss meter) is an instrument which is used to measure specular reflection gloss of a surface. Gloss is determined by projecting a beam of light at a fixed intensity and angle onto a surface and measuring the amount of reflected light at an equal but opposite angle.Macula of retina: The macula or macula lutea (from Latin macula, "spot" + lutea, "yellow") is an oval-shaped pigmented area near the center of the retina of the human eye. It has a diameter of around .Volume rendering: 250px|thumb| A volume rendered cadaver head using view-aligned [[texture mapping and diffuse reflection]]Anterior segment mesenchymal dysgenesis: Anterior segment dysgenesis (ASD) is a failure of the normal development of the tissues of the anterior segment of the eye. It leads to anomalies in the structure of the mature anterior segment, associated with an increased risk of glaucoma and corneal opacity.Generalizability theory: Generalizability theory, or G Theory, is a statistical framework for conceptualizing, investigating, and designing reliable observations. It is used to determine the reliability (i.Charles D. Phelps: Charles Dexter Phelps (September 16, 1937 – September 13, 1985) was a prominent American medical doctor, professor, and researcher in the field of ophthalmology. The clinical studies he oversaw contributed to significant advances in the scientific understanding and surgical and pharmacological treatment of glaucoma.Brain positron emission tomography: Positron emission tomography (PET) measures emissions from radioactively labeled metabolically active chemicals that have been injected into the bloodstream. The emission data are computer-processed to produce multi-dimensional images of the distribution of the chemicals throughout the brain.Plaque-forming unit: In virology, a plaque-forming unit (PFU) is a measure of the number of particles capable of forming plaques per unit volume, such as virus particles. It is a functional measurement rather than a measurement of the absolute quantity of particles: viral particles that are defective or which fail to infect their target cell will not produce a plaque and thus will not be counted.Potocki–Shaffer syndrome: Potocki–Shaffer syndrome (PSS), also known as DEFECT11 syndrome or chromosome 11p11.2 deletion syndrome, is a rare contiguous gene syndrome that results from the microdeletion of section 11.Epiretinal membraneDischarge coefficient: In a nozzle or other constriction, the discharge coefficient (also known as coefficient of discharge) is the ratio of the actual discharge to the theoretical discharge,Sam Mannan, Frank P. Lee, Lee's Loss Prevention in the Process Industries: Hazard Identification, Assessment and Control, Volume 1, Elsevier Butterworth Heinemann, 2005.Beta encoder: A beta encoder is an analog to digital conversion (A/D) system in which a real number in the unit interval is represented by a finite representation of a sequence in base beta, with beta being a real number between 1 and 2. Beta encoders are an alternative to traditional approaches to pulse code modulation.Meridian (perimetry, visual field): Meridian (plural: "meridians") is used in perimetry and in specifying visual fields. According to IPS Perimetry Standards 1978 (2002): "Perimetry is the measurement of [an observer's] visual functions ...Ultrasound-modulated optical tomography: Ultrasound-modulated optical tomography (UOT) is a form of tomography involving ultrasound. It is used in imaging of biological soft tissues and has potential applications for early cancer detection.Neointima: Neointima typically refers to scar tissue that forms within tubular anatomical structures such as blood vessels, as the intima is the innermost lining of these structures. Neointima can form as a result of vascular surgery such as angioplasty or stent placement.Atomic force acoustic microscopy: Atomic Force Acoustic Microscopy (AFAM) is a type of scanning probe microscopy (SPM). It is a combination of acoustics and atomic force microscopy.Serpiginous: Serpiginous, often referring to some chronic medical affliction, signifies it as slowly progressive or "creeping", such as ringworm. Regarding skin ailments in particular, this means that such a disease leaves scar tissue below while continuing to affect the skin above.Age-Related Eye Disease Study: The Age-Related Eye Disease Study (AREDS) was a clinical trial sponsored by the National Eye Institute, one of the National Institutes of Health in the United States.A Randomized, Placebo-Controlled, Clinical Trial of High-Dose Supplementation With Vitamins C and E, Beta Carotene, and Zinc for Age-Related Macular Degeneration and Vision Loss.Intraocular pressurePosterior vitreous detachment: A posterior vitreous detachment (PVD) is a condition of the eye in which the vitreous membrane separates from the retina.Spiral computed tomography: Spiral computed tomography is a computed tomographyAvinash C. Kak and Malcolm Slaney (2001).Avo PhotonicsCable fault location: Cable fault location is the process of locating periodic faults, such as insulation faults in underground cables, and is an application of electrical measurement systems. In this process, mobile shock discharge generators are among the devices used.Assay sensitivity: Assay sensitivity is a property of a clinical trial defined as the ability of a trial to distinguish an effective treatment from a less effective or ineffective intervention. Without assay sensitivity, a trial is not internally valid and is not capable of comparing the efficacy of two interventions.Optic disc pit: An optic disc pit is a congenital excavation (or regional depression) of the optic nerve head resulting from a malformation during development of the eye. Optic pits are important because they are associated with posterior vitreous detachments (PVD) and even serous retinal detachments.Image fusion: In computer vision, Multisensor Image fusion is the process of combining relevant information from two or more images into a single image.Haghighat, M.Refractometry: Refractometry is the method of measuring substances' refractive index (one of their fundamental physical properties) in order to, for example, assess their composition or purity. A refractometer is the instrument used to measure refractive index ("RI").Diabetic retinopathy: ( )RetinoschisisOptic disc drusenOutline of photography: The following outline is provided as an overview of and topical guide to photography:Saal Greenstein syndrome: Saal Greenstein syndrome is a very rare autosomal recessive genetic disorder characterized by stunted growth, short limbs, microcephaly, and an anomalous cleavage of the anterior chamber of the eye. The disorder is similar to Robinow syndrome except for anterior chamber anomalies and, in one case, hydrocephalus.Clonal Selection Algorithm: In artificial immune systems, Clonal selection algorithms are a class of algorithms inspired by the clonal selection theory of acquired immunity that explains how B and T lymphocytes improve their response to antigens over time called affinity maturation. These algorithms focus on the Darwinian attributes of the theory where selection is inspired by the affinity of antigen-antibody interactions, reproduction is inspired by cell division, and variation is inspired by somatic hypermutation.Cardiac imagingPars plana: The pars plana is part of the uvea, choroidea, one of the three layers that comprise the eye. As a part of the ciliary body, it is about 4 mm long, located near the point where the iris and sclera touch and is scalloped in appearance.EndoscopyVector soliton: In physical optics or wave optics, a vector soliton is a solitary wave with multiple components coupled together that maintains its shape during propagation. Ordinary solitons maintain their shape but have effectively only one (scalar) polarization component, while vector solitons have two distinct polarization components.Water injection (oil production): Water injection or water flooding refers to the method in the oil industry where water is injected into the reservoir, usually to increase pressure and thereby stimulate production. Water injection wells can be found both on- and offshore, to increase oil recovery from an existing reservoir.Vitreous membrane: The vitreous membrane (or hyaloid membrane or vitreous cortex) is a layer of collagen separating the vitreous humour from the rest of the eye. At least two parts have been identified anatomically.Ictal-Interictal SPECT Analysis by SPM: ISAS (Ictal-Interictal SPECT Analysis by SPM) is an objective tool for analyzing ictal vs. interictal SPECT scans.Glaukomflecken: Glaukomflecken simply means glaucoma flecks.Dr Khairul Nazri Mohammad (Articles' Author), Waterford General Hospital, IRELAND It is anterior subcapsular or capsular opacity of the lens associated with focal epithelial infarct from past acute angle closure glaucoma.Micromirror device: Micromirror devices are devices based on microscopically small mirrors. The mirrors are Microelectromechanical systems (MEMS), which means that their states are controlled by applying a voltage between the two electrodes around the mirror arrays.Operation Eyesight Universal: Operation Eyesight Universal is a Canada-based international development organisation, founded in 1963. It works to prevent avoidable blindness and to cure blindness that is treatable.Monocular estimate method: The monocular estimate method or monocular estimation method is a form of dynamic retinoscopy widely used to objectively measure accommodative response.Tassinari JT.PlanmecaTomographic reconstruction: Tomographic imaging is applied in Computed Tomography to obtain cross-sectional images of patients. This article applies in general to tomographic reconstruction for all kinds of tomography, but some of the terms and physical descriptions refer directly to X-ray computed tomography.Laser-induced breakdown spectroscopy: Laser-induced breakdown spectroscopy (LIBS) is a type of atomic emission spectroscopy which uses a highly energetic laser pulse as the excitation source. The laser is focused to form a plasma, which atomizes and excites samples.Blueshift: A blueshift is any decrease in wavelength, with a corresponding increase in frequency, of an electromagnetic wave; the opposite effect is referred to as redshift. In visible light, this shifts the color from the red end of the spectrum to the blue end.Anterior interventricular branch of left coronary artery: The left anterior descending artery (also LAD, anterior interventricular branch of the left coronary artery, or anterior descending branch), also known as the "widow maker", is an artery of the heart.Imaging phantom: Phantom}}Optic nerve tumor: An optic nerve melanocytoma is a tumor made up of melanocytes and melanin. These tumors are typically a benign; they can grow, but rarely transform into a malignancy.Laser coagulation: Laser coagulation or laser photocoagulation surgery is used to treat a number of eye diseases and has become widely used in recent decades. During the procedure, a laser is used to finely cauterize ocular blood vessels to attempt to bring about various therapeutic benefits.Micropsia