Training Automatic View Planner for Cardiac MR Imaging via Self-Supervision by Spatial Relationship between Views

TL;DR

This paper introduces an annotation-free, deep learning-based system for automatic cardiac MRI view planning that leverages spatial relationships between views, achieving high accuracy without manual annotations or additional imaging.

Contribution

It proposes a novel self-supervised approach that exploits intersecting lines in stored data for view planning, eliminating manual annotation and improving accuracy over existing methods.

Findings

Achieves mean angle difference of 5.98 degrees

Point-to-plane distance of 3.48 mm

Outperforms atlas-based and deep learning approaches

Abstract

View planning for the acquisition of cardiac magnetic resonance imaging (CMR) requires acquaintance with the cardiac anatomy and remains a challenging task in clinical practice. Existing approaches to its automation relied either on an additional volumetric image not typically acquired in clinic routine, or on laborious manual annotations of cardiac structural landmarks. This work presents a clinic-compatible and annotation-free system for automatic CMR view planning. The system mines the spatial relationship -- more specifically, locates and exploits the intersecting lines -- between the source and target views, and trains deep networks to regress heatmaps defined by these intersecting lines. As the spatial relationship is self-contained in properly stored data, e.g., in the DICOM format, the need for manual annotation is eliminated. Then, a multi-view planning strategy is proposed to aggregate information from the predicted heatmaps for all the source views of a target view, for a globally optimal prescription. The multi-view aggregation mimics the similar strategy practiced by skilled human prescribers. Experimental results on 181 clinical CMR exams show that our system achieves superior accuracy to existing approaches including conventional atlas-based and newer deep learning based ones, in prescribing four standard CMR views. The mean angle difference and point-to-plane distance evaluated against the ground truth planes are 5.98 degrees and 3.48 mm, respectively.