Osteoarthritis Initiative — Cartilage Thickness Maps and Scoring Dataset

Overview This dataset provides knee cartilage thickness maps (CTh-Maps) derived from MRI data of the Osteoarthritis Initiative (OAI) cohort, together with their corresponding cartilage osteoarthritic severity scores (CTh-Score, range 0–100) computed by the automatic framework described in the article. It is published in conjunction with the article: Automatic framework for evaluating osteoarthritic cartilage severity: high-resolution cartilage thickness mapping and scoringEuropean Radiology — DOI: [10.1007/s00330-026-12414-w] (https://doi.org/10.1007/s00330-026-12414-w) Dataset Content OAI_CTh-Maps_CTh-Score_Dataset_v1/ ├── CTh_maps_00m/ # Cartilage thickness maps — baseline (0 months) ├── CTh_maps_12m/ # Cartilage thickness maps — 12 months ├── CTh_maps_24m/ # Cartilage thickness maps — 24 months ├── CTh_maps_36m/ # Cartilage thickness maps — 36 months ├── CTh_maps_48m/ # Cartilage thickness maps — 48 months ├── CTh_maps_72m/ # Cartilage thickness maps — 72 months ├── CTh_maps_96m/ # Cartilage thickness maps — 96 months └── df_cth_score_v1.csv # CTh-Score table for all subjects and timepoints CTh-Maps (CTh_maps_*/) Each subdirectory contains 2D cartilage thickness maps stored as NumPy files (.npy). File naming convention: {ID}_{SIDE}_v1_CTh_map_{Timepoint}.npy Example: 9000099_LEFT_v1_CTh_map_00m.npy Field Description ID OAI participant identifier SIDE Knee side — LEFT or RIGHT Timepoint Visit — 00m, 12m, 24m, 36m, 48m, 72m, or 96m Array format: float64, shape (170, 80) — a 2D projection map of cartilage thickness values (in mm). Background pixels (same for all) are encoded as NaN. CTh-Score table (df_cth_score_v1.csv) A CSV file containing the cartilage osteoarthritic severity score for each knee and timepoint. Column Description ID OAI participant identifier SIDE Knee side — LEFT or RIGHT Timepoint Visit timepoint (e.g. 00m, 12m, …, 96m) CTh-Score Cartilage severity score, continuous value in [0 – 100]. Higher scores indicate greater osteoarthritic severity. Version Dataset version (current: 1.0) Usage import numpy as np import pandas as pd # Load a cartilage thickness map cth_map = np.load("CTh_maps_00m/9000099_LEFT_v1_CTh_map_00m.npy") print(cth_map.shape) # (170, 80) fig, ax = plt.subplots(1, 1, figsize=(12, 5)) # Original image im = ax.imshow(cth_map, cmap='jet_r') ax.set_title('CTh-Map') plt.colorbar(im, ax=ax, fraction=0.046, pad=0.04) fig.tight_layout() plt.show() # Load the CTh-Score table df = pd.read_csv("df_cth_score_v1.csv") print(df.head()) Citation If you use this dataset, please cite the associated article: Automatic framework for evaluating osteoarthritic cartilage severity: high-resolution cartilage thickness mapping and scoring. European Radiology (2026). https://doi.org/10.1007/s00330-026-12414-w OAI Data Access The CTh-Maps were derived from images of the Osteoarthritis Initiative (OAI). Access to the original OAI imaging and clinical data requires registration at:https://nda.nih.gov/oai/