4Dflow-unwrap: A collection of python-based phase unwrapping algorithms

Motivation: Low-Venc PC-MRI acquisitions present the advantage of higher velocity-to-noise ratio (VNR). To the best of the author’s knowledge, no Python-based public repository exists with 4D flow MRI unwrapping algorithms and realistic examples. Goal(s): To share a collection of simple unwrapping tools for 4D Flow MRI and test their performance. Approach: To use three established unwrapping techniques to create a Python package to unwrap 4D flow MRI data. Results: We demonstrate the performance of these algorithms on aortic data including multiple Venc values and undersampling factors. Impact: The Python repository with a collection of simple unwrapping tools facilitates access to unwrapping techniques. These scripts can readily be used to unwrap any PC-MRI dataset.