End-to-End Autonomous Recursive Arborescence Deformable Flow and Non-Linear Hemodynamics for Patient-Specific Coronary Centerline Extraction
Organizations: School of Biomedical Engineering and Technology, Tianjin Medical University, Tianjin 300070, China
Abstract
Extracting patient-specific vascular trees from volumetric medical images is fundamental to computational angiography and non-invasive hemodynamic assessment. Conventional voxel segmentation models often sever delicate bifurcations, while heuristic Euclidean Minimum Spanning Trees introduce non-anatomical shortcuts. Moreover, linear Poiseuille flow neglects quadratic kinetic dissipation across arterial narrowings, underestimating ischemia. We formulate an end-to-end framework decoupling continuous geometric arborescence generation from non-linear hemodynamics. First, an autonomous 3D Ostium Landmark Localization Head with dual-sinus query channels and spherical-gated refinement eliminates centerline seeding dependency, achieving cohort mean localization error of 7.63 mm (7.43 mm LCA, 7.83 mm RCA; 71.4% <= 8.0 mm) from raw contrast context. Second, a Spatially-Grounded Deformable Step Flow Architecture queries continuous 3D feature pyramids via trilinear sampling, sequentially generating trajectories with anchor boundary enforcement (X(0) = P_start). Third, a Top-Down Recursive Arborescence State Machine detects bifurcation peaks via Tree-NMS and parameterizes predecessor parent pointers (p_k < k), guaranteeing single connected acyclic tree topology (beta_0 = 1, beta_1 = 0) with differentiable step termination. Fourth, an iterative Picard non-linear Kirchhoff solver with Young-Tsai / Gould quadratic dissipation enforces machine-precision mass conservation (residual 5.82e-11 mL/s). Across 14 development patients under standardized in-silico stenosis stress testing (Q_0 = 4.0 mL/s), linear Poiseuille flow misclassifies 75% diameter lesions as non-ischemic (FFR > 0.80) in 14/14 cases, whereas our non-linear solver captures functional ischemia (FFR = 0.5864, lesion disparity 32.89 mmHg, p = 6.10e-5) with 3.66x collateral shunting. Test set firewall isolation was maintained.
Figures & tables
| Model Architecture / Evaluated Baseline | Params (M) | Time (s) | Dice (%) | clDice (%) | HD95 (mm) | (%) | (mm) | Stratified [Prox / Mid / Dist] (%) | KCL Res (mL/s) | ||
|---|---|---|---|---|---|---|---|---|---|---|---|
| nnU-Net (Isensee et al. [ 13 ] ) | 31.2 | 8.40 | 14.50 5.20 | 28.00 12.00 | 79.80 3.40 | 81.50 3.90 | 14.20 4.80 | 74.20 3.80 | 3.82 0.95 | 86.4 3.2 / 72.5 4.1 / 42.1 5.8 | N/A |
| SegResNet (Myronenko [ 14 ] ) | 18.5 | 6.10 | 18.20 6.10 | 34.00 15.00 | 78.40 3.90 | 80.20 4.20 | 16.80 5.50 | 72.80 4.10 | 4.15 1.10 | 84.2 3.5 / 70.1 4.4 / 38.5 6.2 | N/A |
| CorSegRec (Qiu et al. [ 21 ] ) | 24.6 | 12.30 | 4.80 2.10 | 6.00 4.00 | 83.20 2.80 | 85.60 2.50 | 9.80 3.10 | 81.50 2.60 | 2.45 0.65 | 89.5 2.5 / 80.2 3.0 / 58.4 4.5 | N/A |
| DeformCL (Zhao et al. [ 28 ] ) | 22.8 | 5.20 | 2.10 1.20 | 0.00 0.00 | 84.10 2.50 | 86.70 2.20 | 7.60 2.40 | 83.60 2.10 | 2.10 0.52 | 90.1 2.2 / 81.8 2.6 / 64.0 3.8 | N/A |
| Baseline 1: Point-Set Oracle ( -NN + MST) | — | 14.50 | 1.00 0.00 | N/A | 76.40 4.50 | 24.50 6.20 | 68.20 4.50 | 5.20 1.40 | 82.5 4.1 / 69.4 4.8 / 45.2 6.5 | N/A | |
| Baseline 2: Centerline Trajectory Oracle (GT Centerlines) | — | — | 1.00 0.00 | 0.00 0.00 | 87.50 1.80 | 91.20 1.40 | 3.39 0.72 | 96.50 1.10 | 0.65 0.15 | 98.5 0.8 / 96.2 1.1 / 92.4 1.5 |
| Module / Configuration | clDice (%) | (%) | Time (s) | ||
|---|---|---|---|---|---|
| Part A: Progressive Framework Ablation | |||||
| (1) Voxel Thinning Baseline | 14.50 5.20 | 28.00 12.00 | 81.50 3.90 | 74.20 3.80 | 8.40 |
| (2) + Continuous Flow Matching | 8.20 3.10 | 14.50 6.20 | 83.40 2.60 | 78.90 2.70 | 2.10 |
| (3) + Ostium Cavity Gating | 5.40 2.20 | 9.20 4.10 | 84.90 2.30 | 81.70 2.20 | 2.40 |
| (4) + Tree State Machine ( ) | 1.00 0.00 | 0.00 0.00 | 85.90 2.10 | 84.50 1.90 | 2.65 |
| (5) Full Proposed Framework | 1.00 0.00 | 0.00 0.00 | 86.40 2.20 | 85.20 1.90 | 2.80 |
| Dataset / Method | Post-Proc. | (Fragments) | sAPLS | Murray MRE |
|---|---|---|---|---|
| DRIVE ( ) | ||||
| U-Net + Thinning | None | 80.75 15.10 | 0.4238 0.1024 | 0.3714 0.0450 |
| U-Net + clDice [ 8 ] | None | 64.85 12.77 | 0.4095 0.1137 | 0.3680 0.0420 |
| VesselTok [ 26 ] | MST | 1.00 0.00 | 0.8223 0.1060 | 1.0180 0.0331 |
| Continuous Flow (Ours) | MST | 1.00 0.00 | 0.8295 0.0842 | 0.0465 0.1987 |
| HRF ( ) |
| Metric / Hemodynamic Property | Healthy (0% Stenosis) | Mild (30% Stenosis) | Moderate (50% Stenosis) | Severe (70% Stenosis) | Severe (75% Stenosis) | Critical (80% Stenosis) |
|---|---|---|---|---|---|---|
| Linear Poiseuille Mean Distal FFR | 0.9995 0.0003 | 0.9934 0.0012 | 0.9812 0.0035 | 0.9385 0.0084 | 0.9152 0.0098 | 0.8156 0.0182 |
| Non-Linear Young-Tsai Mean Distal FFR | 0.9995 0.0003 | 0.9654 0.0041 | 0.8420 0.0125 | 0.6842 0.0210 | 0.5864 0.0245 | 0.4240 0.0312 |
| Mean Lesion Disparity (mmHg) | 0.0000 0.0000 | 2.80 0.35 | 13.92 1.15 | 25.43 1.82 | 32.89 2.15 | 39.16 2.45 |
| Hodges-Lehmann Median Disparity [95% CI] (mmHg) | 0.0000 [0.00, 0.00] | 2.81 [2.62, 3.01] | 13.95 [13.25, 14.65] | 25.48 [24.35, 26.55] | 32.99 [32.15, 33.71] | 39.22 [37.85, 40.50] |
| Paired Wilcoxon Signed-Rank Test | N/A | |||||
| Linear Flow False-Negative Rate ( ) | 0.0% (0/14) | 0.0% (0/14) | 0.0% (0/14) | 100.0% (14/14) | 100.0% (14/14) | 71.4% (10/14) |
| Pipeline Stage | Params | GFLOPs | Peak VRAM | Latency (s) |
|---|---|---|---|---|
| 3D Ostium Localization Head | 1.8 M | 8.4 | 1.2 GB | |
| Deformable Step Flow Matching | 11.6 M | 36.2 | 3.2 GB | |
| Recursive Tree-NMS State Machine | 0.8 M | 4.0 | 1.4 GB | |
| Picard Non-Linear Kirchhoff Solver | 0.0 M | 0.0 | 0.4 GB | |
| Full Autonomous Pipeline | 14.2 M | 48.6 | 3.2 GB | 2.80 0.22 |