9.1. CAD4TB

Computer Aided Detection for Tuberculosis (CAD4TB) is a computer program that automatically calculates a tuberculosis abnormality score in the range of 0 (normal) to 100 (abnormal). The input should be a high quality (compressed) dicom posterior-anterior chest x-Ray (CXR). The mininum age for the person on the scan depends on the CAD4TB version. See section Releases for more details. In some cases, the reported score can be lower than 0:

  • -1: Not a valid posterior-anterior CXR.

  • -2: Invalid dicom: age too low, unsupported dicom SOP, or unsupported device.

  • -3: Processing of the dicom image failed.

Besides the score, the CAD4TB algorithm also outputs a heatmap (Fig. 9.1), which indicates abnormal areas in the lung fields. Abnormalities are color coded: in the range blue (normal), green, yellow, orange, red (abnormal). By clicking the heatmap_cad4tb icon in the viewer, the heatmap can be viewed.

CAD4TB input and output

Fig. 9.1 Example of a CXR with CAD4TB heatmap.

Table 9.1 shows CAD4TB specific buttons available in the Image menu bar.

Table 9.1 Image menu: CAD4TB specific buttons.

Button

Description

Procedure

heatmap_cad4tb

Texture Heatmap

Click the button to show the CAD4TB texture heatmap for the image.

hd_icon

Original HD image

Click the button to show the original high-definition dicom image.

The name of the result is also shown in the top right corner of the Viewer, when the result is enabled.

9.1.1. Releases

  • CAD4TB 5:

  • Minimum age: 16 years

  • Software versions: v4.11.0, v4.12.0, v4.12.1, v4.12.2

  • CAD4TB 6:

  • Minimum age: 4 years

  • Software versions: v6.0.0, v6.1.0