4053
Less is more: zero-shot detection and transfer learning for facet arthropathy localization and classification on lumbar spine MRIs
Upasana Upadhyay Bharadwaj1, Cynthia T Chin1, Valentina Pedoia1, and Sharmila Majumdar1
1Radiology, University of California, San Francisco, San Francisco, CA, United States
This study presents classification of facet arthropathy from MRI using zero-shot facet detection followed by binary classification. Our model achieves an AUC of 0.916 with sensitivity and specificity of 97.8% and 64.1%, respectively and can potentially enhance the clinical workflow.
Figure 5: Summarizes the evaluation of second stage: facet classification. (a) Visualizes the entire evaluation pipeline where a patch is passed as input (b) Visualization of the model's predictions via saliency maps shows clinically valuable features being highlighted- image above highlights the superior articular portion of the facet as well as the ligamentum flavum; image below highlights the superior and inferior portions of the facet, synovium; (c) ROC curve highlighting AUC, sensitivity and specificity at various operating points along with their confidence intervals.
Figure 3: Summarizes the evaluation of first stage: zero-shot facet detection. (a) visualizes location coordinates annotated on the T2-w axial slices by a neuroradiologist. These location coordinates were used purely for evaluating our localization, and not for training our models; (b) visualizes ground-truth bounding boxes generated from the location coordinates in (a) shown in red against predicted bounding boxes from zero-shot detection, shown in yellow.; (c) characterizes the performance with a mAP-IoU graph.