| IDB | image data baser |
|---|---|
| IGS | image-guided surgery; inappropriate gonadotropin secretion; internal guide sequence |
| II | icterus index; image intensification or intensifier; Roman numeral two |
| IIG | interactive image-guided [surgery] |
| IMACS | image archiving and communication system |
| sensory speech centre | The region of the cerebral cortex thought to be essential for understanding and formulating coherent, propositional speech; it encompasses a large region of the parietal and temporal lobes near the lateral sulcus of the left cerebral hemisphere; corresponding approximately to Brodmann's areas 40, 39, and 22. Synonym: sensory speech centre, Wernicke's area, Wernicke's field, Wernicke's region, Wernicke's zone. (05 Mar 2000) |
|---|---|
| sensory system agents | Drugs that act on neuronal sensory receptors resulting in an increase, decrease, or modification of afferent nerve activity. (12 Dec 1998) |
| sensory thresholds | The minimum amount of stimulus energy necessary to elicit a sensory response. (12 Dec 1998) |
| sensory tract | See: lemniscus. (05 Mar 2000) |
| somatic sensory cortex | Somatosensory cortex, the region of the cerebral cortex receiving the somatic sensory radiation from the ventrobasal nucleus of the thalamus; it represents the primary cortical processing mechanism for sensory information originating at the body surfaces (touch) and in deeper tissues such as muscle, tendons, and joint capsules (position sense); it corresponds approximately to Brodmann's areas 1, 2, 3 on the postcentral gyrus. Synonym: somesthetic area. (05 Mar 2000) |
| neuropathies, hereditary motor and sensory | A group of slowly progressive inherited disorders in which the predominant involvement is the peripheral motor neurons with lesser involvement of the peripheral sensory neurons. Neuronal degeneration and atrophy are characteristic of these disorders. Some of the associated characteristics are phytanic acid excess, optic atrophy, and retinitis pigmentosa. (12 Dec 1998) |
| neuropathies, hereditary sensory and autonomic | A group of inherited disorders in which there is selective involvement of the peripheral sensory and autonomic neurons and degeneration of fibres by axonal atrophy and degeneration. Five types of disorders have been described and classified type I through type v. (12 Dec 1998) |
| Abbe theory of image formation | <optics, physics> Abbe's theory is based on the fact that a non-self-luminous particle, which is illuminated by an extraneous source, gives rise to diffracted light rays, in addition to the dioptric pencil. He stated that to form a good microscopical image as many of the diffracted rays as possible should be intercepted by the objective. With closely ruled lines, his theory is easily demonstrated by observing the back lens of the objective, for here the diffracted rays can be observed directly if the aperture diaphragm is closed. It can be shown that, when the illumination is arranged to exclude the diffracted images, resolution is lost. (11 Mar 1998) |
| accidental image | Continuation of visual impression after cessation of stimuli causing the original image. (12 Dec 1998) |
| body image | A term for the concept which each individual has of his own body as an object in and bound by space, independently and apart from all other objects. (12 Dec 1998) |
| radiographic image enhancement | Improvement in the quality of an X-ray image by use of an intensifying screen, tube, or filter and by optimum exposure techniques. Digital processing methods are often employed. (12 Dec 1998) |
| radiographic image interpretation, computer-assisted | Computer systems or networks designed to provide radiographic interpretive information. (12 Dec 1998) |
| real image | An image formed by the convergence of the actual rays of light from an object. Synonym: inverted image. (05 Mar 2000) |
| catatropic image | <ophthalmology, physiology> The two images formed by the anterior and posterior surfaces of the cornea and the two images formed by the anterior and posterior surfaces of the lens. Synonym: catatropic image, Purkinje images, Sanson's images. (05 Mar 2000) |
| virtual image | <microscopy> Such as seen in a mirror or through a magnifier. A virtual image has no real existence in space as does a real image from a lens. It does have a definite location, however, caused by the angles of divergence of the rays received by the eye. This can be shown by the common school experiment of placing a pin coincident with its mirror image behind a sheet of glass acting as a partial mirror. Its location can also be placed in design by extrapolating backwards to a focus. If a magnifier is used as it should be, with the object at its focus, the virtual image is at infinity. The same is true for a microscope focused for the relaxed eye. See: distance of virtual image. (05 Aug 1998) |