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Result : Searchterm 'Image Guidance' found in 0 term [] and 54 definitions []
| previous 11 - 15 (of 54) nextResult Pages : [1 2 3 4 5 6 7 8 9 10 11] | | | | Searchterm 'Image Guidance' was also found in the following service: | | | | |
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Quick Overview
Please note that there are different common names for this artifact.
NAME
Crisscross, Herringbone
DESCRIPTION
Crisscross or herringbone structures throughout the image
This artifact appears as a herringbone pattern scattered over the whole image in any direction only on one slice or on multiple slices. The causes of this are many and various, like e.g. electromagnetic spikes created by the gradients, electronic equipment inside the MR procedure room, or fluctuating AC current.
Image Guidance
Sometimes it is sufficient to change flickering light bulbs.
If the problem increases or keeps on existing, it should be addressed by a service representative. | | | | | |
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Quick Overview
DESCRIPTION
Anomalous intensities in an image
Crosstalk is an artifact introduced into images by interference between adjacent slices of a scan, caused by a slice profile that is not ideal due to the constraints of the measurement technology. If the slice distances are too small, there is cross talk between the slices, which can affect T1 contrast.
Image Guidance
This artifact can be eliminated by limiting the minimum spacing (for the most sequences a minimum gap 10% and for IR sequences 20%) between the slices. Crosstalk can also be reduced by selection of interleaved slices (so a slice gap will not be necessary), but interleaved data acquisition can produce large mean intensity differences between adjacent slices. | | | | • View the DATABASE results for 'Crosstalk (Artifact)' (2).
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Quick Overview
Please note that there are different common names for this artifact.
HELP
Larger range of sensitivity
Noise introduced into digitized signals by the finite voltage resolution of the digitizer.
You can see the effects of quantization if the noise level is smaller than the digitizer quantum.
If the signal dynamic range is too great, the highest intensities from overloading the digitizer may result in the weaker features being lost in the digitization noise.
Image Guidance
This can be resolved by using an analog to digital converter with a larger range of sensitivity or by using techniques to reduce the dynamic range, e.g. suppressing the signal from water in order to detect the signal from less abundant compounds. | | | | • View the DATABASE results for 'Digitization Noise Artifact' (2).
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| | | Searchterm 'Image Guidance' was also found in the following service: | | | | |
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Quick Overview
DESCRIPTION
Image distortion
Eddy currents can cause artifacts in images and may seriously degrade overall magnet performance.
Image Guidance
| | | | • View the DATABASE results for 'Eddy Current Artifact' (2).
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Quick Overview
DESCRIPTION
Line across the center of the image
REASON
Combination of problems
Image Guidance
If the problem persists, it must be addressed by a service representative. | | | | • View the DATABASE results for 'FID Signal Artifact' (2).
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