MONAI-Physio 2026.11.1

Highlights

• More reliable shape-model fitting. WorkflowFitStatisticalModelToPatient
  now runs its initial alignment with RegisterModelsICPITK, rebuilt as ITK
  point-set ICP with free rotation (optionally restricted to one axis). On the
  Duke heart cohort it beat the previous VTK ICP on all 29 cases in 1-2 s
  instead of 8-14 s, and it succeeds on lung cases where the VTK ICP failed.
• Lung fits use only the lung labels. The TCIA-lung tutorials pass the
  segmenter's lung labels, not the whole-body labelmap, so the lung model can
  no longer grow into the heart, liver or chest wall.

Fixes

• RegisterModelsPCA: the target-to-model distance term is now in the same
  units as the distance map, so neither term outweighs the other. New
  keyword-only options distance_map_clip_mm and distance_map_scale.
• WorkflowEvaluateMovement.surface_rmse_mm uses a GPU (Warp) closest-point
  kernel instead of vtkImplicitPolyDataDistance, which crashed
  intermittently.
• Tutorial 8 (lung) removes outputs of phases it no longer registers, so
  Tutorial 9 cannot train on stale surfaces.
• Tutorial 13 refits the heart when the shape model is newer than its cached
  fit, fixing "Fitted reference mesh has N points, expected M".

Tutorials and tests

• Tutorials 11, 14 and 15 are long-running statistical studies, run manually;
  they are no longer tests and have no test mode.
• Faster test mode: 3 PCA components, 50 training epochs (weights kept apart
  from the full run's), and every other respiratory phase for lung Tutorial 8.
• Tutorial baselines regenerated for the new ICP.

Tooling and docs

• utils/strip_notebook_outputs.py and a pre-commit hook keep notebook
  diffs to code.
• New experiment: per-point cardiac displacement CSV
  (experiments/Heart-3DCT_to_CSV).
• FAQ: what the point-count mismatch error means and how to replace
  pre-trained weights.

Upgrading

• Fits change with the new ICP: re-run Tutorials 7-9 to retrain networks on
  them, or download the matching pre-trained models (move the existing
  tutorials/network_weights/<model> directory aside first).
• See docs/developer/migration_2026.11.1.md for API changes.

What's Changed

• ENH: Fit SSMs with point-set ICP; slim tutorial test runs; strip notebooks by @aylward in #171
• BUG: Fix PR 171 review issues: PCA log_level order, stale lung phases by @aylward in #172
• BUG: Refit Tutorial 13 heart model when the shape model is newer; FAQ by @aylward in #178
• ENH: Release 2026.11.1 by @aylward in #179

Full Changelog: 2026.11.0...2026.11.1