Reconstructing 3D bone geometry from 2 X-ray silhouettes using a statistical shape model + differentiable rendering [P]

Excerpt

Working on a pipeline that recovers a patient specific 3D distal femur from two orthogonal X-ray views (PA + lateral). No CT, no neural network, no massive training set. approach: build a PCA shape model from 50 CT-derived femur meshes (MedShapeNet), then fit it to two silhouettes using PyTorch3D's soft rasterizer with sigma annealing. 10 shape coefficients, Mahalanobis prior to keep things plausible, Adam optimizer, ~1000 iterations. The part that took the longest (and made me suffer the most t