Image Artifacts And Distortion; Warnings - Boston Scientific WaveWriter Alpha Manual Del Usuario

Image Artifacts and Distortion

The WaveWriter Alpha systems have minimal image distortion when the device is out of the field of view.
Significant image distortion can result from the presence of the device within the field of view. Image
artifacts and distortion resulting from the presence of the device and the Leads within the field of view
must be considered when selecting the field of view and imaging parameters. These factors must also be
considered when interpreting the MRI images.
Careful choice of pulse sequence parameters and location of the imaging plane may minimize MR image
artifacts. However, the reduction in image distortion obtained by adjustment of pulse sequence parameters
will usually compromise signal-to-noise ratio.
The following general principles should be followed:
• Avoid using the body receive coil if possible. Use a local receive-only coil instead.
• Use imaging sequences with stronger gradients for both slice and read encoding directions. Use
higher bandwidth for both radio-frequency pulse and data sampling.
• Choose an orientation for the read-out axis that minimizes the appearance of in- plane distortion.
• Use a shorter echo time for gradient echo technique, whenever possible.
• Be aware that the actual imaging slice shape can be curved in space due to the presence of the
field disturbance of the neurostimulator.
• Identify the location of the implant in the patient, and when possible, orient all imaging slices away
from the implanted neurostimulator.

Warnings

• If the MRI targeted image area is near the neurostimulator, it may be necessary to move the
neurostimulator to obtain an image, or use alternate imaging techniques. MRI images may be
severely distorted or image target areas can be completely blocked from view near the implanted
neurostimulation system components, especially near the neurostimulator.
• If the neurostimulator is removed, remove the entire neurostimulation system. Do not remove the
neurostimulator and leave the Lead system implanted as this can result in higher than expected
Lead heating under MRI exposure. Testing has not been completed to demonstrate safety of this
configuration under MRI exposure. Excessive heating can result in tissue damage or serious
patient injury.
ImageReady™ MRI Full Body Guidelines for WaveWriter Alpha™ and WaveWriter Alpha™ Prime Spinal Cord Stimulator Systems
Safety Information
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