Inspiration
I run the PACS and teleradiology infrastructure for a statewide government hospital network in Bihar, India. Radiologists who read remotely often work from a single laptop screen, while a hospital reading room has several large diagnostic monitors. A headset can give anyone that multi-monitor reading room anywhere. Hand tracking makes it practical: radiologists already pinch, drag, and point all day, and they do not want to hold controllers.
What it does
- Opens a seated reading room with three large monitors, a worklist, and a measurements panel, all within arm's reach.
- Load studies from the worklist with a pinch, then scroll slices, adjust window/level, zoom, pan, probe Hounsfield units, and measure findings in millimetres.
- PRIOR and CURRENT scans scroll in sync, so you can measure how a lung nodule has grown between visits (8.6 mm to 13.6 mm in the demo case).
- Two-hand pinch zooms an image; pinching a panel's title bar moves the monitor anywhere around you; one tap brings the panels back.
- Every control works with a pinch-ray or by simply tapping it with a fingertip. No controller is needed at any point.
How we built it
- WebXR with three.js, so it runs in the Meta Quest Browser with no install and opens in seconds.
- A unified input layer turns WebXR hand pinch-rays, fingertip pokes, and a desktop mouse into the same press/drag events.
- Each viewport renders CT slices on a canvas with a real window/level transform from Hounsfield units, plus zoom, pan, overlays, and measurement lines.
- To avoid any patient-data risk, all CT studies are synthetic phantoms generated in code: a chest CT at two time points with a growing nodule, and a head CT with an acute subdural pattern.
- Seated-first design:
localreference space, controls on a tilted desk toolbar. - The demo video was recorded in Meta's Immersive Web Emulator (IWER) as a Meta Quest 3 with hand tracking, with scripted hand movements; the narration is an AI voice.
Challenges we ran into
- Precise image work by hand: mapping small hand movements to window/level and slice scrolling without jitter. Dragging is measured on the image plane, so you can move outside the image while adjusting.
- Making buttons easy to hit both by pinch-ray and by direct touch, without double presses.
- Producing realistic-looking CT data without using any real patient images.
Accomplishments that we're proud of
- A full read, compare and measure workflow done entirely with hands, in under a minute from launch.
- The PRIOR vs CURRENT comparison: the nodule growth is visible and measurable side by side.
What we learned
Hands are a natural fit for image review: pinch-and-drag for contrast feels closer to a workstation mouse than controllers do, and a spatial layout removes the need to tile windows.
What's next for Reading Room XR
- Loading real DICOM files (local or from a PACS via DICOMweb) with proper de-identification.
- Voice dictation of findings into a structured report.
- Multi-user review, so a radiologist and a referring doctor can look at the same study together.
- MPR (coronal and sagittal) and 3D volume views.
Built With
- github
- javascript
- meta-quest
- three.js
- webxr