Telemed USB ultrasound systems

Supported hardware devices

This device is used for image acquisition from Telemed ultrasound systems.
Tested only with MicrUs devices (http://www.pcultrasound.com/products/micrus/index.html) but other Telemed devices should be compatible, too.
Link to manufacturer’s website: http://www.pcultrasound.com

Supported platforms

Installation

Requires drivers provided by Telemed for running (otherwise Plus application will not start).
It is recommended to run the Telemed imaging software to set all imaging parameters, as Plus currently can set only a subset of all imaging parameters.

Device configuration settings

Type: TelemedVideo
AcquisitionRate: (Optional, default: 30)
LocalTimeOffsetSec: (Optional, default: 0)
FrameSize: Maximum size of an image frame in pixels. The image is scaled so that image vertically fills the specified rectangle size, therefore if the frame size is too narrow (first component is too small) then the two sides of the image may be clipped; if the frame is too wide then there will be solid filled stripes on the left and right sides. If larger values are specified then a higher-resolution image is created. (Optional, default: 512 512)
DepthMm: Set the depth [mm] of B-mode ultrasound. If not specified (or value is <0) then the current value is kept.
FrequencyMhz: Ultrasound transmitter frequency. If not specified (or value is <0) then the current value is kept. [MHz].

ThiMode: Tissue harmonic imaging (THI) mode, specified as either a value of the Telemed THI_MODE enumeration or a human-readable enum token. If not specified (or value is <0) then the current value is kept. Changing this parameter keeps the transmitter frequency as close as possible to its current value while switching between THI modes. THI exploits the nonlinear propagation of ultrasound through tissue: as sound travels, harmonic frequencies of the original transmit frequency build up, and imaging that harmonic echo instead of the fundamental echo reduces near-field clutter/reverberation and improves contrast resolution.

Enum token	Numeric value	Meaning
`THI_MODE1`	1	Conventional (non-harmonic) imaging: transmitting and receiving frequency are the same. Despite the “THI” prefix, per the Telemed SDK programmer’s guide this is the traditional/fundamental frequency mode, i.e. the “off” state for harmonic imaging.
`THI_MODE2`	2	Tissue harmonic imaging: receiving frequency is 2x the transmitting frequency. Availability depends on the beamformer/probe combination in use.
`THI_MODE2_ITHI`	258	Pulse inversion THI: two opposite-polarity pulses are transmitted per scan line and the received echoes are summed, cancelling the fundamental component while reinforcing the (nonlinear) harmonic component. Gives better fundamental/harmonic separation than `THI_MODE2` at the cost of frame rate.

Not every mode/frequency combination is available on every probe; the device only reports success if an exact THI mode match exists somewhere in its enumerated frequency table (the closest available frequency for that mode is then selected). For example, testing on one ArtUS probe found only THI_MODE1 (at 2/3.5/5 MHz) and THI_MODE2_ITHI (at 2.01 MHz) in the table – no THI_MODE2 entry existed at all for that probe. If the requested mode isn’t available, the operation fails and the log lists the (frequency, THI mode) pairs the probe actually supports.

This parameter can also be changed/retrieved at runtime with the SetUsParameter/GetUsParameter OpenIGTLink commands using the parameter name ThiMode.

DynRangeDb: Dynamic Range [dB] of B-mode ultrasound. If not specified (or value is <0) then the current value is kept.
GainPercent: Is the gain percentage of B-mode ultrasound. If not specified (or value is <0) then the current value is kept. Valid range: 0-100.
PowerDb: Power to be used for imaging, as a number of dB below maximum. If not specified (or value is >0) then the current value is kept. Valid range is -20 to 0.
SpeckleReductionEnabled: Enable (TRUE) or disable (FALSE) speckle reduction (ClearView) filtering of B-mode ultrasound. If not specified then the current value is kept.

SpeckleReductionMethod: Speckle reduction filter method, specified as either a value of the Telemed CLEAR_VIEW enumeration (for example 306) or a human-readable enum token (for example SRF_NVC6). The value encodes the filter family (hundreds digit) and the filtration level (1-16 within each family, higher = stronger filtering). If not specified (or value is <0) then the current value is kept.

Values	Filter family	Notes
1-16	ClearView (`SRF_CV1..16`)	Requires purchased license and inserted USB dongle key
101-116	PureView (`SRF_PV1..16`)	Generally available
201-216	NeatView GPU (`SRF_NV1..16`)	Availability depends on graphics adapter and drivers
301-316	NeatView CPU (`SRF_NVC1..16`)	Generally available
401-416	QuickView (`SRF_QV1..16`)	Reserved for future use by Telemed
501-516	`SRF_NVO1..16`	Present in SDK 4.1.0 headers, undocumented

Per the Telemed SDK programmer’s guide, in most cases only PureView and CPU-based NeatView are available; Telemed’s own default scanning parameter files use 306 (NeatView CPU, level 6, equivalent to SRF_NVC6). Note that speckle reduction filters may reduce the frame rate. Both speckle reduction parameters can also be changed at runtime with the SetUsParameter OpenIGTLink command (parameter names SpeckleReductionEnabled and SpeckleReductionMethod).

DynamicFocusEnabled: Enable (TRUE/FALSE or 1/0) dynamic focus mode. If not specified then the current value is kept.
FocusesNumber: Number of active focal zones (integer). If not specified (or value is <0) then the current value is kept.
FocusSet: Focus set index (integer). If not specified (or value is <0) then the current value is kept.
FrameAveraging: Temporal frame averaging level (integer). If not specified (or value is <0) then the current value is kept.
ViewAreaPercent: View area percentage (integer). If not specified (or value is <0) then the current value is kept.
LineDensity: Line density value from Telemed LINE_DENSITY enum (integer; examples: 8, 14, 16, 22, 24, 32). If not specified (or value is <0) then the current value is kept.
ImageEnhancementEnabled: Enable (TRUE/FALSE or 1/0) image enhancement. If not specified then the current value is kept.
ImageEnhancementMethod: Image enhancement method, specified as either a Telemed IMAGE_ENHANCEMENT enum token or its numeric value. If not specified (or value is <0) then the current value is kept.

Enum token

Numeric value

Meaning

IMAGE_ENHANC_SHARPEN

1

Sharpen

IMAGE_ENHANC_SHARPENMORE

2

Sharpen more

IMAGE_ENHANC_SMOOTH

3

Smooth

IMAGE_ENHANC_SMOOTHMORE

4

Smooth more
Rejection: Rejection filter level (integer). If not specified (or value is <0) then the current value is kept.
Negative: Enable (TRUE/FALSE or 1/0) negative palette display. If not specified then the current value is kept.
ChangeScanDirection: Enable (TRUE/FALSE or 1/0) scan-direction change (mirror). If not specified then the current value is kept.
RotateImage: Image rotation (0, 90, 180, 270; enum values 0..3 are also accepted). If not specified (or value is <0) then the current value is kept.

All Telemed-specific parameters above can also be changed/retrieved at runtime by SetUsParameter and GetUsParameter OpenIGTLink commands using the same parameter names.

DataSources: Exactly one DataSource child element is required (Required)
- DataSource: (Required)
  - PortUsImageOrientation: (Required)
  - BufferSize: (Optional, default: 150)
  - AveragedItemsForFiltering: (Optional, default: 20)
  - ClipRectangleOrigin: (Optional, default: 0 0 0)
  - ClipRectangleSize: (Optional, default: 0 0 0)

Example configuration file PlusDeviceSet_Server_TelemedVideoCapture.xml

<PlusConfiguration version="2.1">

  <DataCollection StartupDelaySec="1.0" >
    <DeviceSet
      Name="PlusServer: Telemed ultrasound device"
      Description="Broadcasting acquired video through OpenIGTLink"
    />
    <Device
      Id="VideoDevice"
      Type="TelemedVideo" >
      <DataSources>
        <DataSource Type="Video" Id="Video" PortUsImageOrientation="UN"  />
      </DataSources>
      <OutputChannels>
        <OutputChannel Id="VideoStream" VideoDataSourceId="Video" />
      </OutputChannels>
    </Device>
    <Device
      Id="CaptureDevice"
      Type="VirtualCapture"
      BaseFilename="RecordingTest.igs.mha"
      EnableCapturingOnStart="FALSE" >
      <InputChannels>
        <InputChannel Id="VideoStream" />
      </InputChannels>
    </Device>
  </DataCollection>

  <CoordinateDefinitions>
    <Transform From="Image" To="Reference"
      Matrix="
        0.2 0.0 0.0 0.0
        0.0 0.2 0.0 0.0
        0.0 0.0 0.2 0.0
        0 0 0 1" />
  </CoordinateDefinitions>

  <PlusOpenIGTLinkServer
    MaxNumberOfIgtlMessagesToSend="1"
    MaxTimeSpentWithProcessingMs="50"
    ListeningPort="18944"
    SendValidTransformsOnly="true"
    OutputChannelId="VideoStream" >
    <DefaultClientInfo>
      <MessageTypes>
        <Message Type="IMAGE" />
      </MessageTypes>
      <ImageNames>
        <Image Name="Image" EmbeddedTransformToFrame="Reference" />
      </ImageNames>
    </DefaultClientInfo>
  </PlusOpenIGTLinkServer>

</PlusConfiguration>

Enum token	Numeric value	Meaning
`IMAGE_ENHANC_SHARPEN`	1	Sharpen
`IMAGE_ENHANC_SHARPENMORE`	2	Sharpen more
`IMAGE_ENHANC_SMOOTH`	3	Smooth
`IMAGE_ENHANC_SMOOTHMORE`	4	Smooth more