tomography

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Related to helical computed tomography: spiral scan, spiral computed tomography

tomography

[tə′mäg·rə·fē]
(electronics)

Tomography

 

(also body section roentgenography or sectional radiography), a technique of roentgenological study that is used to produce a photograph of a layer lying at a specific depth in the object under study.

Ordinary roentgenography results in the production on film of an overall image, from which it is not always possible to determine the true shape and size of a formation or the depth at which it lies. The production of a roentgenogram of a single layer is based on the movement of two of the three components (the X-ray tube, the X-ray film, and the object of study). In the most common technique, the patient is motionless, and the X-ray tube and film magazine move around him in opposite directions. The use of tomography makes possible the study of the trachea, the bronchi, and the blood vessels and the detection of infiltrates and cavities of the lungs, calculi in the kidney, gallbladder, and bile ducts, and tumors in the adrenals and urinary system. The combined use of X-ray contrast media and tomography (sectional bronchography, urography, and so on) is highly effective.

REFERENCE

Gladysz, B. Tomografiia v klinicheskoi praktike. Warsaw, 1965. (Translated from Polish.)

E. A. GRIGORIAN

tomography

An X-ray technique that shows a single plane (slice) of the object under examination, typically a part of the human body. See CAT scan.
References in periodicals archive ?
All these patients underwent non contrast enhanced helical computed tomography (CT) scan.
Although these studies have used excretory urography (IVP) as the reference standard, noncontrast helical computed tomography (CT) appears to be a superior reference standard.[1,2] The authors of this study examined the accuracy of hematuria testing compared with a reference standard of helical CT and attempted to differentiate between dipstick screening and different thresholds of microscopic hematuria.
Objectives: To study the use of helical computed tomography 2-D and 3-D images, and virtual endoscopy in the evaluation of airway disease in neonates, infants and children and its value in lesion detection, characterisation and extension.
Helical computed tomography (Asteion - Toshiba) was used for all patients.
A prospective cohort study evaluated spontaneous passage rates of ureteral calculi by size in 172 patients who were diagnosed by unenhanced helical computed tomography. (2) Investigators found spontaneous passage rates of 87% for 1-mm calculi, 76% for 2- to 4-mm calculi, 60% for 5- to 7-mm calculi, 48% for 7- to 9-mm calculi, and 25% for calculi larger than 9 mm.
Helical computed tomography of the neck with contrast infusion detected a possible vascular hemangioma in the right posterior lateral wall of the subglottic region.
Helical computed tomography (CT) of the neck and chest with three-dimensional reconstruction detected an abnormal communication between the trachea and the esophagus that was consistent with a tracheoesophageal fistula.
Can noncontrast helical computed tomography replace intravenous urography for evaluation of patients with acute urinary tract colic?