computed tomography (redirected from Computed tomograghy)

tomography /to·mog·ra·phy/ (to-mog´rah-fe) the recording of internal body images at a predetermined plane by means of the tomograph.

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computed tomography  (CT), computerized axial tomography (CAT) an imaging method in which a cross-sectional image of the structures in a body plane is reconstructed by a computer program from the x-ray absorption of beams projected through the body in the image plane.

positron emission tomography  (PET) a nuclear medicine imaging method similar to computed tomography, except that the image shows the tissue concentration of a positron-emitting radioisotope.

single-photon emission computed tomography  (SPECT) a type in which gamma photon–emitting radionuclides are administered and then detected by one or more gamma cameras rotated around the patient, using the series of two-dimensional images to recreate a three-dimensional view.

ultrasonic tomography  the ultrasonographic visualization of a cross-section of a predetermined plane of the body.

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Computed tomography (CT scan)

X rays are aimed at slices of the body (by rotating equipment) and results are assembled with a computer to give a three-dimensional picture of a structure.

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computed tomography (CT)

[kəmpyo̅o̅′tid]

a radiographic technique that produces an image of a detailed cross section of tissue. The procedure, first used in 1972, is painless and noninvasive and requires no special preparation. It is 100 times more sensitive than conventional radiography. CT uses a narrowly collimated beam of x-rays that rotates in a full arc around the patient to image the body in cross-sectional slices. An array of detectors, positioned at several angles, records those x-rays that pass through the body. The image is created by a computer that uses multiple attenuation readings taken around the periphery of the body part. The computer calculates tissue absorption and produces a representation of the tissues that demonstrates the densities of the various structures. Tumor masses, infractions, bone displacement, and accumulations of fluid may be detected. For cardiologic examination, ultrafast CT is electrocardiogram-triggered and allows visualization of cardiac function and blood flow. Because modern CT equipment does not involve motion of the x-ray tube, heat loading is not a problem and multilevel images can be acquired in a very short time, sometimes during a single held breath. During a period of two held breaths, as many as 50 continuous tomographic images can be produced in a single-slice mode. Formerly called computerized axial tomography.

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computed tomography,

n radio-graphic imaging technique used to record a cross-section of tissue.

Computed tomography.

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computed tomography (CT) (tōmog´rfē),

n a radiographic body scanning technique in which thin or narrow layer sections of the body can be imaged for diagnostic purposes. The technique uses a computer-linked radiographic machine to focus the radiographs on a particular section of the body to be viewed.

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computed tomography

a radiological imaging technique that produces images of 'slices' through a patient's body. See also computed tomography.

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computed tomography

Computed axial tomography, computerized tomography, CT scanning Imaging A special radiographic diagnostic technique in which multiple X-rays are taken from different angles in a single plane and a series of 2-D images–'slices' of the different tissue densities–eg fat, muscle, bone, etc, are constructed by computer; in contrast to conventional radiology, CT results in a 1000-fold ↑ in image resolution, and can pinpoint lesions < 2 mm in greatest dimension; dyes may be injected IV to ↑ resolution of abnormal tissue and blood vessels, or radiocontrast can be used for dynamic testing. See Hounsfield units, Multislice CT, PET/CT, Quantitative CT, Spiral CT, TACT, Ultrafast CT. Cf Magnetic resonance imaging, Ultrasonography.

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Patient discussion about Computed tomograghy.

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.