April 2025 · September 2026
The next CT, side by side
Explore matching locations in both scans. One slider moves them together.
The same location in both scans
The 2026 scan is aligned to the 2025 scan. Both use the same grayscale window.
Scroll normally to move down the page. Use the slider or + / − to change slices. Focus an image and use arrow keys for one slice, or Shift + arrow for five.
Use the matching slices to look around and check alignment. Colored differences represent displayed CT intensity, not measured bone growth, loss, or healing. Positioning, reconstruction, metal artifacts and small alignment errors can mimic change. The new report lists no prior comparison.
How alignment and brightness work
The September 2026 scan is rigidly registered to the April 2025 grid. The tibia/fibula option aligns around the distal shafts; the talus option adds a local refinement. The display uses downsampled, windowed pixels. Metal and regions where MAR and standard reconstructions disagree are excluded from the difference colors by default, separately for each alignment.
Brightness matching adjusts how the 2026 bone appears, using a single setting estimated from the tibia/fibula away from the talus. It stays the same across slices and viewing directions. Soft tissue brightness is unchanged. Turn it off to see the original shared display window; Difference always uses the original windowed values. This display adjustment does not calibrate the scans or measure healing.
- Tibia / fibula overlap
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- Talus overlap, before → after refinement
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- Display grid
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Overlap scores are alignment checks, not measurements of disease or treatment outcome. The two scans use different kernels and slice thicknesses. Inspect original studies with a musculoskeletal radiologist for a clinical comparison.