title: FloWave.US: validated, open-source, and flexible software for ultrasound blood flow analysis.
abstract: Automated software improves the accuracy and reliability of blood velocity, vessel diameter, blood flow, and shear rate ultrasound measurements, but existing software offers limited flexibility to customize and validate analyses. We developed FloWave.US-open-source software to automate ultrasound blood flow analysis-and demonstrated the validity of its blood velocity (aggregate relative error, 4.32%) and vessel diameter (0.31%) measures with a skeletal muscle ultrasound flow phantom. Compared with a commercial, manual analysis software program, FloWave.US produced equivalent in vivo cardiac cycle time-averaged mean (TAMean) velocities at rest and following a 10-s muscle contraction (mean bias <1 pixel for both conditions). Automated analysis of ultrasound blood flow data was 9.8 times faster than the manual method. Finally, a case study of a lower extremity muscle contraction experiment highlighted the ability of FloWave.US to measure small fluctuations in TAMean velocity, vessel diameter, and mean blood flow at specific time points in the cardiac cycle. In summary, the collective features of our newly designed software-accuracy, reliability, reduced processing time, cost-effectiveness, and flexibility-offer advantages over existing proprietary options. Further, public distribution of FloWave.US allows researchers to easily access and customize code to adapt ultrasound blood flow analysis to a variety of vascular physiology applications.
authors: Vanderbilt University Institute of Imaging Science, Nashville, Tennessee; Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee; crystal.coolbaugh@vanderbilt.edu.
authors: Crystal L
authors: 0000-0002-1825-598X
authors: CL
authors: Coolbaugh
authors: Vanderbilt University Institute of Imaging Science, Nashville, Tennessee.
authors: Emily C
authors: EC
authors: Bush
authors: Vanderbilt University Institute of Imaging Science, Nashville, Tennessee; Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee; Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee.
authors: Charles F
authors: CF
authors: Caskey
authors: Vanderbilt University Institute of Imaging Science, Nashville, Tennessee; Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee; Department of Biomedical Engineering, Vanderbilt University, Nashville, Tennessee; Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, Tennessee; and.
authors: Bruce M
authors: BM
authors: Damon
authors: Vanderbilt University Institute of Imaging Science, Nashville, Tennessee; Department of Radiology and Radiological Sciences, Vanderbilt University, Nashville, Tennessee; Department of Physical Medicine and Rehabilitation, Vanderbilt University, Nashville, Tennessee.
authors: Theodore F
authors: TF
authors: Towse
mesh_terms: D000465:Algorithms; D001158:Arteries / Q000033:anatomy & histology / Q000000981:diagnostic imaging* / Q000502:physiology*; D001783:Blood Flow Velocity / Q000502:physiology*; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D020407:Internet; D019047:Phantoms, Imaging; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012984:Software; D014463:Ultrasonography / Q000295:instrumentation / Q000379:methods*
keywords: Doppler; edge detection; flow-mediated dilation; regional blood flow; wave tracking