Enhancing Embolic Signal Visualization in Transcranial Doppler Graphs

Hi there.

I have a transcranial Doppler signal, and I need to detect the embolic signals. The graph I'm obtaining in cm/s is this one:

But I need to enhance the visualization of this. My signal has a gain of 31dB, but this software allows improving the visualization of embolic signals by adjusting the dB. Here are two examples with 6dB and -2dB (the time intervals between the two images are different). Is the gain difference enough to provide the differences between the images? How can I achieve an image like these from the software?

Thank you.

Patrícia

Answer 1

[William Rose]

@Patrícia,

Please upload data files that go with the two screenshot images which show possible emboli.

Adjust the color scale range with clim(). This will take some experimentation. Make a custom color map. I demonstrated a way to do this in one of my comments in response to your earlier question. You can also make a custom colormap with the colormap editor.

Are you using a Sonara or Sonara/tek system? Or Dolphin system? The reason I am asking is that perhaps the device manual will allow a better understanding of the options, including the dB setting. On Sonara trans-cranial Doppler systems, the dB setting is only for acquiring data, and is not adjustable during playback or display. The Dolphin TCD uses a prorietary alorithm to detect and display high intensity transient signals (HITS), i.e. to detect and display embolic signals. It may not be feasible to reverse-engineer their prorietary algorithm.

FYI, you never accepted an answer to your previous question.

[Patrícia]

Hi :)

Here is the file data:

% session_time::10-12-33             
% time::21-13-15-31                                    
% gates::2                                               
% prf::4525                                              
% samples::2201054                                      
% transmitting_freq1::2 MHz
% label1::MCA_R
% spec_gate_sv1::8
% spec_gate_depth1::50
% spec_gate_gain1::31
% spec_gate_filter1::150
% transmitting_freq2::2 MHz
% label2::PCA_L
% spec_gate_sv2::8
% spec_gate_depth2::54
% spec_gate_gain2::38
% spec_gate_filter2::150

I've added the file here so you can download it.

The data was collected with DWL Software, but the screenshots from the previous comment were done using the TCD Simulator software.

I'm trying to change the colors to have an image similar to the TCD simulator, and I'm also attempting to modify some parameters to visualize the HITS on the velocity chart.

Thank you.

[William Rose]

@Patrícia,

I downloaded the file you posted. I am not able to work on this for at least two weeks. I didn;t know there was a TCD simulator. Interesting. Did you have to purchase the activation key in order to make those figures?

[Patrícia]

@William Rose I found the same software at this link here. I believe that here the activation key is not necessary.

Thank you.

Patrícia

[William Rose]

@Patrícia, thanks for the link.