Time-resolved angiography with stochastic trajectories for dynamic contrast-enhanced MRI in head and neck cancer: Are pharmacokinetic parameters affected?

• Published in: Medical physics (Lancaster) 2016-11, Vol.43 (11), p.6024-6032
• Main Authors: Panek, Rafal, Schmidt, Maria A., Borri, Marco, Koh, Dow-Mu, Riddell, Angela, Welsh, Liam, Dunlop, Alex, Powell, Ceri, Bhide, Shreerang A., Nutting, Christopher M., Harrington, Kevin J., Newbold, Kate L., Leach, Martin O.
• Format: Article
• Language: English
• Subjects: Adult; Algorithms; Angiography; Biological material, e.g. blood, urine; Haemocytometers; biomedical MRI; blood; cancer; Cell processes; cellular biophysics; Contrast Media - pharmacokinetics; DCE; Digital computing or data processing equipment or methods, specially adapted for specific applications; Edge enhancement; Female; Fluid mechanics and rheology; Fluid transport and rheology; Fourier transforms; haemorheology; Head and Neck Neoplasms - diagnostic imaging; Head and Neck Neoplasms - metabolism; Heart; Humans; Image data processing or generation, in general; image enhancement; Image enhancement or restoration, e.g. from bit‐mapped to bit‐mapped creating a similar image; image resolution; image sampling; image sequences; Involving electronic [emr] or nuclear [nmr] magnetic resonance, e.g. magnetic resonance imaging; Magnetic Resonance Imaging; Male; Medical image contrast; medical image processing; Medical image spatial resolution; Middle Aged; Phantoms, Imaging; Relaxation times; Spatial resolution; squamous cell cancer of the head and neck; Stochastic Processes; tumours; TWIST; undersampling
• ISSN: 0094-2405; 2473-4209
• DOI: 10.1118/1.4964795

Purpose: To investigate the effects of different time-resolved angiography with stochastic trajectories (TWIST) k-space undersampling schemes on calculated pharmacokinetic dynamic contrast-enhanced (DCE) vascular parameters. Methods: A digital perfusion phantom was employed to simulate effects of TWIST on characteristics of signal changes in DCE. Furthermore, DCE-MRI was acquired without undersampling in a group of patients with head and neck squamous cell carcinoma and used to simulate a range of TWIST schemes. Errors were calculated as differences between reference and TWIST-simulated DCE parameters. Parametrical error maps were used to display the averaged results from all tumors. Results: For a relatively wide range of undersampling schemes, errors in pharmacokinetic parameters due to TWIST were under 10% for the volume transfer constant, K trans, and total extracellular extravascular space volume, Ve . TWIST induced errors in the total blood plasma volume, Vp , were the largest observed, and these were inversely dependent on the area of the fully sampled k-space. The magnitudes of errors were not correlated with K trans, Vp and weakly correlated with Ve . Conclusions: The authors demonstrated methods to validate and optimize k-space view-sharing techniques for pharmacokinetic DCE studies using a range of clinically relevant spatial and temporal patient derived data. The authors found a range of undersampling patterns for which the TWIST sequence can be reliably used in pharmacokinetic DCE-MRI. The parameter maps created in the study can help to make a decision between temporal and spatial resolution demands and the quality of enhancement curve characterization.