Quantification software
technical features

Tissue Perfusion

• To quantify blood perfusion in organs (non-cardiac indications).
  Provide a reliable method for quantifying organ perfusion, obtained from DCE-US examinations.
• With specific tools to monitor perfusion of the same tissue over time.
  Provide means for displaying temporal evolution of perfusion parameters on the same tissue after successive acquisitions.
   

Tissue Normalization

• To highlight differences in contrast enhancement patterns in different regions of interest of the analysed tissue.
  Provide tools to summarize the specificities of the difference signals signatures into a single, easy-to-read color-coded image.
   

Low-Intensity Signal

• To detect vascularization and determine vascularized areas in low-intensity signal areas. 
• Specific vascularization parameters: ROI area, perfused area, relative perfused area, mean opacification.
   

In order to allow visual perception of all the useful information contained in the echo signal, the ultrasound system manufacturers amplify the echo signal in a non-linear manner, so as to enhance the lower amplitude echo signals. Particularly, the video signal is always zero for values of the echo signal below a minimum value. The desired result implies a loss of proportionally between the video signal and the echo signal. Furthermore, each manufacturer of medical ultrasound scanner has a peculiar approach to the implementation of this log-compression.

Linearization of the video signal is therefore important for deriving correct functional information relating to the blood perfusion in the body-part under analysis. The linearization indicates the processing that makes the amplitude of the video signal (i.e., the pixel values) directly proportional to the local concentration of the contrast agent in the corresponding pixel locations. This linearized signal provides a direct representation of the (relative) local blood volume in the respective portions of the body-part (since the contrast agent concentration is related, i.e., proportional, to the blood volume). As a consequence, the linearized signal allows a correct assessment of the blood perfusion in the body-part.

VueBox^® Research linearization has been validated with multiple ultrasound systems during dose ranging experiments to demonstrate the proportionality between signal measured in VueBox^® Research and contrast agent concentration.

Curve Fitting: BOLUS

• The Bracco patented models used in VueBox^® Research fit the experimental time-intensity curve in an optimal way.

Curve Fitting: REPLENISHMENT

• Bracco has optimized curve fitting models for both bolus and replenishment kinetics.

Perfusion Quantification: Parametric Imaging

• A parametric image is the synthetic representation of a parameter over time for each individual pixel in the ROI.

Management of analysis results

Export of graphs and images (BMP, TIF, JPEG), data (Excel compatible) and clips (WMV)

• Customizable and easy-to-read.
• Free selection of report contents.
• Multiple-page print-ready formatting.
• Export to PDF (non-modifiable file).

The Dynamic Vascular Pattern (DVP) processing uses a selected ROI as reference and displays the hyper-enhanced and hypo-enhanced pixels over time by using warm and cold colour hues.
A classification of DVP signal is performed at the pixel level. 
 

In addition to DVP, the Dynamic Vascular Pattern Parametric (DVPP) summarizes the dynamic enhancement of each pixel by assigning a specific color corresponding to one of the four types of enhancement model.

The final results are presented as parametric maps summarizing the dynamic vascular signature in a ROI in comparison with neighbouring parenchyma.

The objective of the Low-Intensity Signal package is to detect vascularisation and determine vascularized areas in low-intensity signal areas.

The assessment of low-intensity areas in much higher-energy surroundings  encounters several major challenges such as:

• Risk of signal contamination by contrast signals of high-energy surrounding areas. 
• Dependence of measured intensity values from system settings.
• Very low signal to noise ratio.
• Need of an adaptative dual scale display.

Parametric image of the perfused area of a Low Intensity Region and the respective numeric values

The VueBox^® Research Low-Intensity Signal package includes tools that overcome these issues. 
The detection of low signal relies on an automatic and adaptative noise threshold, making the measurements independent from settings and users. The analysis is performed on a subset of images within optimal time windows that help reduce contamination by the high-intensity area.

The Low-Intensity Signal package performs a MIP-based assessment of vascularised areas and provides specific quantitative perfusion parameters. Time intensity curves (TIC) from the high and low intensity areas can be displayed simultaneously using different intensity scales, to allow the simultaneous representation of both curves in one graph.
 

Time windows selection on dual-scale graph, showing TIC from High Intensity Region and Low Intensity Region.

Key features:

• Specific vascularization parameters: ROI area, perfused area, relative perfused area, mean opacification.
• Adaptative enhancement threshold based on noise level..
• Analysis performed in optimal time windows (plateau of maximum enhancement in the low-intensity area).
• Dual-scale display of time intensity curves of the high and low intensity signal.