artifact

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artifact

 [ahr´tĭ-fakt]
1. any artificial product; a structure or appearance that is not natural, but is due to manipulation.
2. distortion or fuzziness of an image caused by manipulation, such as during compression of a digital file.
film artifact artificial images on x-ray films due to storage, handling, or processing.
phantom artifact artificial images seen with conventional tomography.
standardization artifact an electrical stimulus of 1 mV deliberately introduced into the electrocardiogram so that pulse amplitudes on the tracing can be adjusted to 10 mm. The amplitudes of the P, QRS, and T intervals can be accurately evaluated only on an electrocardiogram thus standardized.

ar·ti·fact

(ar'ti-fakt),
1. Anything, especially in a histologic specimen or a graphic record, which is caused by the technique used and does not reflect the original specimen or experiment.
2. A skin lesion produced or perpetuated by self-inflicted action, as in dermatitis artefacta.
Synonym(s): artefact
[L. ars, art, + facio, pp. factus, to make]

artifact

/ar·ti·fact/ (ahr´tĭ-fakt″) any artificial (man-made) product; anything not naturally present, but introduced by some external source.

artifact

also

artefact

(är′tə-făkt′)
n.
1. A phenomenon or feature not originally present or expected and caused by an interfering external agent, action, or process, as an unwanted feature in a microscopic specimen after fixation, in a digitally reproduced image, or in a digital audio recording.
2. An inaccurate observation, effect, or result, especially one resulting from the technology used in scientific investigation or from experimental error: The apparent pattern in the data was an artifact of the collection method.

ar′ti·fac′tu·al (-făk′cho͝o-əl) adj.

artifact

[är′təfakt]
Etymology: L, ars, skill, facere, to make
anything artificially made; may be extraneous, irrelevant, or unwanted, such as a substance, structure, or piece of data or information. In radiological imaging, spurious electronic signals may appear as an artifact in an image with as much strength as the signals produced by the real objects, thereby confusing the radiologist and the results of any examination.

artefact

(1) A structure not normally present, but produced by some external action; something artificial.
(2) The distortion of a substance or signal which interferes with or obscures the interpretation of a study, or a structure that is not representative of a specimen’s in vivo state, or which does not reflect the original sample, but rather is the result of an isolation procedure, its handling or other factors. Artefacts in electronic readout devices (e.g., EEG, EKG, and EMG) may be due to loose leads or electrical contacts.
 
Cardiology
An electrical impulse of noncardiac origin which is recorded as a vertical spike on an EKG or other ECG monitor (e.g., a pacemaker pulse); electrical signals from muscle contractions, or myopotentials, are called muscle artefacts.
 
Histology
Any change in tissue that occurs during tissue processing which may alter a tissue’s appearance and possibly the diagnosis.

Imaging
The artefact seen depends on the procedure. For example, in a barium enema, where zones of inconstant segmental contractions of the colon may be confused with organic constrictions or anatomic variations due to mucosal or intramural tumours, or a metal surgical clip that obscures an anatomical structure.

artifact

Artefact A structure not normally present, but produced by some external action; something artificial; the distortion of a substance or signal, which interferes with or obscures the interpretation of a study, or a structure that is not representative of a specimen's in vivo state, or which does not reflect the original sample, but rather the result of an isolation procedure, its handling or other factors; artifacts in electronic readout devices–eg, EEG, EKG, and EMG, may be due to loose leads or electrical contacts Cardiac pacing An electrical impulse of noncardiac origin which is recorded as a vertical spike on an EKG or other ECG monitor–eg a pacemaker pulse; electrical signals from muscle contractions, or myopotentials, are called muscle artifacts Imaging The artifact seen depends on the procedure–eg, barium enema, where zones of inconstant segmental contractions of the colon may be confused with organic constrictions or anatomic variations, due to mucosal or intramural tumors, or a metal surgical clip that obscures an anatomical structure. See Beam-hardening artefact, Edge artefact, Mosaic artefact, Ring artefact.

ar·ti·fact

(ahr'ti-fakt)
1. Anything (especially in a histologic specimen or a graphic record) that is caused by the technique used or is not a natural occurrence but is merely incidental.
2. A skin lesion produced or perpetuated by self-inflicted action, such as scratching in dermatitis artefacta.
Synonym(s): artefact.
[L. ars, art, + facio, pp. factus, to make]

artifact,

n 1. anything made by human hands or activities.
2. a product that may develop during an analysis performed to identify the composition of a substance. Mainly a consequence of the conditions of the analysis.

ar·ti·fact

, artefact (ahr'ti-fakt)
Anything, especially in a histologic specimen or a graphic record or x-ray, caused by the technique used that does not reflect the original specimen or experiment.
[L. ars, art, + facio, pp. factus, to make]

artifact (är´təfakt),

n a blemish or image in the radiograph that is not present in the roentgen image of the object.

artifact

a structure or appearance that is not natural, but is due to manipulation (man-made).

dermatohistopathological artifact
may be due to sampling errors (selection, preparation or technique) or processing of specimens.
radiological artifact
defects in the x-ray film image due to faults in the cassette (screen artifact) or in the film (film artifact).
static artifact
a mark on x-ray film caused by discharge of static electricity.
ultrasound artifact
irregularities produced in the image display. See acoustic shadowing, acoustic enhancement, comet-tail, reverberation.
References in periodicals archive ?
Removal of Blocking artifacts in DC and AC filtering", IEEE Conference on Signal Processing, 1: 229-232.
The LBT increases the coding gain and reduces the blocking artifact but it has more ringing artifacts.
higher resolution without noise and blocking artifacts, even at high compression