Prism (viewer)
Measurements and annotations
Length, angle, ROI, and annotation tools; quick vs full measurement lists; DICOM-SR and measurement groups.
Prism’s measurement tools are built on Cornerstone tool primitives, grouped in the toolbar as quick and more (exact labels: primary and overflow in the product).
Tool catalog (by id)
| Tool | What it is for | Notes |
|---|---|---|
| Length | Basic distance on plane | l shortcut for speed. |
| Bidirectional | Two perpendicular calipers in one (lesion L/W) | Common for RECIST-style checks on plane. |
| Angle | Two-line or corner angle in-plane | Vascular or orthopedic angles. |
| CobbAngle | Scoliosis / Cobb-style angle pattern | As supported by the tool implementation. |
| RectangleRoi / CircleRoi / EllipticalRoi | Region stats (mean, area) when supported | Check panel readouts. |
| FreehandRoi | Irregular region | Opaque boundaries for odd shapes. |
| ArrowAnnotate | Text pointer to call out a finding for screenshots or addendum | Non-quant, communication first. |
| Probe | Pixel value or vector probe (modality/stored value dependent) | Good for CT number quick checks. |
WindowLevel, Pan, and Zoom are navigate tools, not stored measurements, but you often switch between them; see Window, level, and LUT.
Brush / Eraser in the type system are for segmentation—see Segmentation, not the classic measurement set.
Workflow patterns
- Triage nodule —
Lengthon longest axis, screenshot or note for the report. - Aortic stenosis (informal check) — Angle in the right plane, after MPR; formal analysis still happens on a hemodynamics workstation in many services.
- HCC in segment — Freehand or ellipse for rough area, Bidirectional for long/short in one shot.
Measurement groups and panel
- Measurements are organized into groups (for example, manual vs loaded from DICOM-SR). The panel lists id, type, and summary stats when available.
- You can show/hide a group, lock a measurement, or delete from the list depending on permissions (some DICOM-SR–hydrated items may be read-only if marked protected in the underlying object model).
DICOM-SR measurements may hydrate from prior reads when a structured report series exists, giving you a read-only reference layer.
Annotations (Arrow / text)
- ArrowAnnotate is useful for educational or MDT stills where you need an arrow, not a number.
Related
- Series and thumbnails — make sure the correct series is active before measuring.
- Synchronization — if two panes show the same slice index, you still measure in one viewport; switch active viewport to pick the right plane.