1. Acquire a 3D PDI sweep in region of interest using a mechanical 3D/4D probe. This can be done by selecting the 3D/4D hard key on the keyboard. Then select start on the right trackball key. Once the sweep is finished you will be in a sectional plane display.
Note: PDI Volume Quantification is a tool used with Power Doppler Imaging. Color Doppler is not applicable with this tool.
Define Volume of Interest to analyze
1. Select Vocal on TP.
2. To use VOCAL imaging, select start on the TP. A green arrow will appear on the screen. Using right set key and trackball, trace Volume of interest (VOI) around region of vascularity.
3. Use rotary knob on the bottom right corner of the TP to rotate Volume. The volume will be rotated 30 degrees each time. You will repeat tracing the volume of interest 6 times. Note: PDI Volume Quantification provides the tools for a semi-quantitative assessment of flow through a Volume of interest.
Calculate volume
1. Once done tracing volume of structure, calculate volume on Touch Panel using Calc Volume button.
2. Select Static 3D tab.
3. Select Volume Histogram on Touch Panel (TP).
4. Gray and PDI histograms and indices will be calculated when VOI is defined.
Vascular Flow Index
1. Once Volume Histogram is selected on TP, the ratio, Vascular Flow Index and the mean will be seen calculated on the screen.
2. The ratio is determined by the number of weighted color voxels to total number of voxels within the Volume.
3. The Vascular Flow Index is a ratio of the sum of weighted color intensities to total number of voxels inside VOI. This Vascular index gives an estimation of blood supply through a tumor or vascular region due to flow estimation.
4. The mean is an average of all intensities. A Mean signal level for all the Power Doppler voxels inside VOI will be calculated.