Volcano CORE Mobile, Operator'S Manual

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Glossary
Acoustic reference:
The collection of an acoustic reference removes the universal minor
image imperfections called ringdown artifact, which is caused by catheter noise and
offset characteristics.
Diameter: The depth of field to which the ultrasound image data is acquired.
DICOM (Digital Imaging and Communications in Medicine):
A format for storing
images on DVD and transferring images and patient data over a network. The DICOM
standard facilitates the exchange of patient images and data among different pieces and
types of medical imaging equipment.
Gain: The intensity of the ultrasound echoes; a higher gain setting results in a brighter
image with more intense echoes.
ILD = In-Line Digital : Two-dimensional, 360° rotation, real-time longitudinal view
generated by visually “stacking” hundreds of cross-sectional intravascular ultrasound
images.
PIM = Patient Interface Module: The imaging catheter connects to the Patient Interface
Module which excites the catheter’s transducer elements to transmit ultrasonic energy to
the surrounding tissue. The PIM amplifies and processes the resultant echo signals from
the transducer.
Post-processing: Any operation conducted on a stored ultrasound image. Measurements,
annotations, and retrieving and clearing data are examples of post-processing.
Ringdown Artifact: Ringdown artifact is a result of multiple phenomena such as
acoustic and RF signal crosstalk between neighboring acoustic elements on synthetic
aperture catheters and the innate physical properties of ultrasound crystals and catheter
tips. In addition, the operating frequency, temperature, and the size and geometry of the
ultrasound elements contribute to the magnitude and appearance of the artifact.
Sensitivity: During ChromaFlo imaging, blood/ luminal flow rates can vary from 4
cm/sec up to 110 cm/sec. The Volcano system is equipped to display, in color, 5 viewable
flow ranges. This capability is accessed via the Sensitivity control which is available on
the Adjust Image menu. There are 5 selections: Sensitivity 1 for high flow rate vessels
and Sensitivity 5 for low flow rate vessels. Typically Sensitivity 3 through 5 will provide
the best visualization of coronary vessel flow rates.
For any given sensitivity setting, areas where the relative blood/ luminal flow rates are
higher are more yellow; areas where they are slower are more red. By increasing the
sensitivity setting to a higher value, one can shift towards yellow the color of slower
moving areas of blood flow; by decreasing the sensitivity setting to a lower value, one
can shift towards red the color of faster moving areas of blood flow.