computerized axial tomography - definition of computerized axial tomography in the Medical dictionary - by the Free Online Medical Dictionary, Thesaurus and Encyclopedia.

com·put·er·ized axial tomography (k

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n. Abbr. CAT

Tomography used in diagnostic studies of internal bodily structures, in which computer analysis of a series of cross-sectional scans made along a single axis of a bodily structure or tissue is used to construct a three-dimensional image of that structure. Also called computed tomography.

computerized axial tomography (CAT).

See computed tomography.

computerized

adapted for analysis, storage and retrieval on a computer.

computerized axial tomography

see computed tomography.

computerized clinical data storage

clinical data is keyed in the examination room, the clinical pathology laboratory and the radiology section. It is then capable of analysis in terms of diagnosis, identity of the veterinarian, drugs used, inventory reset and accounts raised. Accounts can be made up and posted and a monthly statement of income and expenditure prepared.

computerized transaxial tomography

see computed tomography.

tomography

any method that produces images of single tissue planes. In conventional radiology, tomographic images (body-section radiographs) are produced by motion of the x-ray tube and film or by motion of the patient that blurs the image except in a single plane. In reconstruction tomography (CT and PET) the image is produced by a computer program. Called also laminagraphy, planigraphy, body-section technique.

computerized axial tomography

see computed tomography (below).

computed tomography (CT)

a revolutionary radiological imaging modality that uses computer processing to generate an image (CT scan) of the tissue density in a 'slice' about 0.5 inch thick through the patient's body. Called also computerized axial tomography (CAT) and computerized transaxial tomography (CTAT).

Because CT is noninvasive and has high contrast resolution, it has replaced some radiographic procedures using contrast media. However, in some areas the injection of contrast further enhances the image. CT also has a better spatial resolution than scintillation imaging (about 1 mm for CT compared with 15 mm for a scintillation camera).

positron emission tomography (PET)

a combination of computed tomography and scintillation scanning. Natural biochemical substances or drugs tagged with a positron-emitting radioisotope are administered to the subject. After injection, the tagged substance (tracer) is localized in specific tissues like its natural analog. When the isotope decays, it emits a positron, which then annihilates with an electron of a nearby atom, producing two 511 keV gamma rays traveling in opposite directions 180° apart. When the gamma rays trigger a ring of detectors around the subject, the line between the detectors on which the decay occurred is stored in the computer. A computer program (reconstruction algorithm), like those used in computed tomography, produces an image of the distribution of the tracer in the plane of the detector ring.

Most of the isotopes used in PET scanning have a half-life of only 2 to 10 minutes. Therefore, they must be produced by an on-site cyclotron and attached chemically to the tracer and used within minutes. Because of the expense of the scanner and cyclotron, PET is used only in research centers.

ultrasonic tomography

the ultrasonographic visualization of a cross-section of a predetermined plane of the body; see B-mode ultrasonography.

Patient discussion about computerized axial tomography.

Q. I get bad headaches had ct scans and m.r.i. even sinus surgery, suffering 2yrs now, dizzness occurs too..

A. If all prior medical investigations turned out normal, and sinus surgery didn't help relieve your symptoms, I would suggest the reason for your headaches is probably migraine attacks, that can cause severe headaches, and no CT scan or MRI can diagnose them. The diagnosis is made clinically, by your doctor. Migraine headaches can be eased by proper medications, before and during an attack. You should consult a neurologist.