Select a tool from the toolbar (or press its shortcut), then draw on the image. Click a measurement to select it; press Delete to remove the selected one, or use the eraser (E).
Tools & shortcuts
Length (M) — distance between two points.
Angle (G) — three-point angle.
Rectangle ROI (O) and Ellipse ROI (C) — area with mean/standard-deviation statistics.
Arrow (A) — point to a finding.
Text label (T) — free text (entered via an in-app dialog).
Rotate (R) and 90° rotation with [ / ].
Exporting key images
Each view has a small select button (top-right of the image) — toggle it (or press Space) to mark a slice. A Download action then appears in the toolbar to save the selected images; multiple selections are zipped. (The selection overlay is hidden in presentation mode for a clean view.)
Notes
Measurements live on the slice/series you drew them on.
All annotations stay on your device — they are part of your local view, not written back into the original DICOM files.