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Tomography is imaging by sections or sectioning. A device used in tomography is called a tomograph, while the image produced is a tomogram. The method is used in medicine, archaeology, biology, geophysics, oceanography, materials science, astrophysics and other sciences. In most cases it is based on the mathematical procedure called tomographic reconstruction. The word was derived from the Greek word tomos which means "a section", "a slice" or "a cutting". A tomography of several sections of the body is known as a polytomography. DescriptionIn conventional medical X-ray tomography, clinical staff make a sectional image through a body by moving an X-ray source and the film in opposite directions during the exposure. Consequently, structures in the focal plane appear sharper, while structures in other planes appear blurred. By modifying the direction and extent of the movement, operators can select different focal planes which contain the structures of interest. Before the advent of more modern computer-assisted techniques, this technique, ideated in the 1930s by the radiologist Alessandro Vallebona, proved useful in reducing the problem of superimposition of structures in projectional (shadow) radiography. From Wikipedia under the
GNU Free Documentation License  octnews.org unknown 2007-01-01 18:15:29 David W. Kolstad appointed President and Chief Executive Officer of LightLab Imaging; also published in Optical Coherence . Tomography. News · Axsun Technologies Announces Exclusive Cardiac Supply Agreement for Advanced OCT Tunable Lasers ... octnews.org unknown 2009-06-10 12:38:08 IF LIGHT passed through objects, rather than bouncing off them, people might now talk to each other on photophones . Alexander Graham Bell demonstrated such a device in 1880, transmitting a conversation on a beam of light. ... octnews.org unknown 2009-06-09 21:25:59 Absorption and scattering processes in biological tissues are studied through reflectance spectroscopy in tissue-like phantoms. For this aim, an experimental setup is designed to independently control both processes in hemoglobin and ... From Google Blog Search: "tomography" where can i find computerised tomography (CT) angiography scan images.want to learn reading them? Q. need a website where a doctor or nonradioogist can learn how to read CT angiography images Asked by xmen - Wed Jan 16 06:22:44 2008 - - 1 Answers - 0 Comments A. Consult a radiologist. he may be able to show you images / tell you about the site. Answered by a k - Sat Jan 19 11:34:29 2008 what is a PET (Positron emission tomography) Scan? Q. what is a PET (Positron emission tomography) Scan? Asked by havok_amor - Mon Oct 27 15:32:47 2008 - - 4 Answers - 0 Comments A. a PET scan is a type of nuclear medicine imaging. Nuclear medicine is a branch of medical imaging that uses small amounts of radioactive material to diagnose or treat a variety of diseases, including many types of cancers, heart disease and certain other abnormalities within the body. Nuclear medicine or radionuclide imaging procedures are noninvasive and usually painless medical tests that help physicians diagnose medical conditions. These imaging scans use radioactive materials called radiopharmaceuticals or radiotracers. Depending on the type of nuclear medicine exam you are undergoing, the radiotracer is either injected into a vein, swallowed or inhaled as a gas and eventually accumulates in the organ or area of your body being… [cont.] Answered by shizzle - Mon Oct 27 15:38:09 2008 in principle why might acoustic tomography detect any warming of the ocean?
Q. in principle why might acoustic tomography detect any warming of the ocean? Asked by jumpy789 - Tue Nov 21 08:15:03 2006 - - 1 Answers - 0 Comments A. The speed of sound in water (including seawater) depends on several factors, but most important is the the temperature of the water. By measuring the time it takes for an acoustic signal to travel from a source to a receiver, one can determine the average temperature along the path followed by that sound signal. (Other factors that include sound velocity or travel time include salinity, pressure (i.e. pressure-induced changes in density), and ocean currents.) By measuring the average temperature along many different paths, one can reconstruct a 3-dimensional "map" of the temperature distribution in the oceans. By following the changes in temperature over time, one can detect long-term changes in the temperature distribution and hence… [cont.] Answered by hfshaw - Tue Nov 21 19:15:57 2006 From Yahoo Answer Search: "tomography" |
