- 00000018WIA30D18970GYZ
- id_400243631.3
- May 23, 2022 1:34:38 AM
Safety
Read all cautions and warning before you use READY View.
This section presents information necessary to successfully complete the working safely READY View processes. Specifically, you need to understand:
Safety-related information
Map generation
Protocol-specific cautions and safety messages
Film and save images
Fused images
Graphs
Image Comparison
Image quality
Image reliability
Measurement
Patient confidentiality
Safety-related software messages
Messages that provide information and warnings related to the current system status are displayed on the Advantage Workstation screens. Some of these messages may be related to safety issues. For example, a message may warn that a screen or printed image will be enlarged or reduced, and this must be taken into consideration when making a diagnosis. It is important that you take note of and act on the information given in these messages.
General READY View safety messages
- Use the
on the Review Controller to review all the input images for motion artifact or incorrect geometry before processing. - Use the Advanced review tool to review all the input images for the presence of artifacts before processing.
- Ensure recomputation of maps after modification of input parameters.
- Ensure that there is no discrepancy between functional maps, graphs, statistics, and ROI numbers due to various screen saves taken after re-computation of the maps or modification of the ROIs.
- READY View shall not be used alone as a basis for diagnostic or treatment purposes.
- Clinical review of functional map images should always include the review of the source images used for the computation, especially if or when the source images had been acquired in a research or non-clinical setting.
Safety-related information
Post-processing algorithms compute output parameters by means of functions. Parametric images or maps are then derived by displaying the value of the parameter for each pixel location.
Pixel values report a quantity of a dimension expressed in units representative of the system of measurement (for instance mm2/sec for ADC map).
Be aware that there are various factors impacting the absolute quantification values estimated from the native MR input acquisitions. It is not recommended to directly compare the absolute values of the READY View parametric images with those of different software packages or from published work, as these values may be based on different input parameters, computation algorithms, normalization factors, etc. It is recommended that all comparisons be based on relative measures.
Therefore, under no circumstances should diagnostic and/or treatment decisions be based solely on absolute values or cut-off values found in the literature.
| CAUTION | |
|---|---|
Non-GE data DICOM image data are provided to advanced visualization algorithms from various sources such as different vendors, research sequences. A range of parameters can affect the parametric map results. GE validates a sample of product datasets but cannot exhaustively cover the range of acquisition parameters available on the market. READY View post-processing may be applied to non-GE product datasets. These non-GE datasets must be carefully interpreted:
Please note that the processing may fail and maps won’t be generated, due to technical incompatibilities. | |
| CAUTION | |
|---|---|
United States Federal law restricts this device to use by or on the order of a physician. | |
Map generation
| CAUTION | |
|---|---|
If the Compute button is available, always click it to re–compute the functional maps after making changes to the input parameters. The changes are not taken into account automatically. | |
Protocol-specific cautions and safety messages
| Protocol | Message |
|---|---|
| 3DASL |
Important: Care should be taken when using quantitative measures of cerebral blood flow from 3DASL in clinical populations. Differences in CBF values may be seen when the same subject is scanned on different systems and coils. Diagnostic and treatment decisions should not be based solely on these absolute values.
|
| Diffusion Tensor |
Important: Diffusion Tensor images attempt to characterize behavior of water molecules in imaged tissue. Therefore, fiber tracking representation actually displays algorithmically predicted water molecule direction. These displays may be only representative of the actual white matter anatomy. A trained neuro radiologist is required to make the association between the rendered tract display and the actual patient’s anatomy.
|
| R2Star and T2Map | When using Multi-echo FGRE/FSPGR for tissues with short T2* relaxation times, the echo spacing and first echo should be as small as possible (around 1 ms for first echo time) to ensure confidence in the fit of the R2* value. The best way to achieve this is by using a high band width, low matrix, and not using User CV-16, positive gradient polarity. |
| fMRI | Ensure that the activation and rest durations are set correctly before computing functional maps in the Functional protocol. |
| DWI | Ensure that you are aware of the b-values used during the acquisition. When b-values are unknown or user would like to select a subset of the acquired b-values, be sure to enter these values in their correct sequence in the UI before computing functional maps. Changed text to be in sync with READY View 5788747-1EN_r2 |
| Brainstat AIF |
|
| MR Standard |
|
| SER | Ensure that the enhancement ranges are set correctly before computing functional maps in the SER protocol. |
Film and save images
Important: When saving images with a new series description, make sure that this description matches the saved images.
Fused images
Important: Images used to fuse together should be registered before loading.
Graphs
Important: Graphs are generally meaningless for image series that do not constitute a dynamic data set (for instance if all images have different locations).
Image Comparison
Important: When acquiring MR data, geometric distortions vary from one sequence to another. This is particularly the case when comparing anatomical sequences (such as T2 or T1) and Echo-Planar diffusion sequences. This may render comparison between, for instance, Diffusion Tensor maps and anatomical reference images imprecise - correcting the distortion will only improve maps accuracy, but does not guarantee geometrical accuracy.
Image quality
Important: Correct segmentation and quantification is critically dependent on such factors as acquisition image quality, acquisition dose, voxel size (image resolution and inter-slice distance), artifact and low contrast. Anomalies may occur because of limitations in the available data. It is the responsibility of the user to verify the result of the segmentation and quantification tools before using the data for analysis.
Image reliability
Important: Review outputs of processing to ensure image orientation integrity.
Important: 3D or slab reconstructions provide additional supplemental information, complementing diagnosis that should be based on classical techniques.
Important: It remains the responsibility of the user to determine whether the time resolution in the exam is acceptable for the purpose of the analysis.
Important: The user should be aware that spatial smoothing settings impact image quality of the perfusion maps. Low setting values may result in maps with decreased image quality. In case of insufficient image quality, the user may increase the smoothing setting value but must be aware that the processing time will also increase.
Measurement
| Warning | |
|---|---|
While ROI statistics are calculated on displayed volumes in Volume Viewer (segmented or not), the Summary Table only displays statistics calculated from original volumes (non-segmented). | |
| CAUTION | |
|---|---|
Measurements are calculated and displayed by the software to one decimal place (0.1 mm square). You should be aware that the real measurement accuracy is generally considerably less for several reasons. The main factors are image set resolution, display resolution, acquisition accuracy and display settings. | |
Important: Under no circumstances should the absolute pixel value from saved functional maps be used for direct measurements.
Patient confidentiality
Important: The equipment on which the READY View application runs includes one or more hard disk drives, which may hold medical data related to patients. Such equipment may in some countries be subject to regulations concerning the processing of personal data and the free circulation of such data. It is strongly recommended that access to patient files be protected from all persons not in medical attendance.