Time-resolved angiography with stochastic trajectories for dynamic contrast-enhanced MRI in head and neck cancer: Are pharmacokinetic parameters affected?
OBJECTIVE
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, Ktrans, 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 Ktrans, Vpand 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.
CR-UK Cancer Imaging Centre, London SM2 5PT, United Kingdom; The Institute of Cancer Research, London SM2 5PT, United Kingdom; and The Royal Marsden NHS Trust, London SM2 5PT, United Kingdom.
Rafal
R
Panek
CR-UK Cancer Imaging Centre, London SM2 5PT, United Kingdom; The Institute of Cancer Research, London SM2 5PT, United Kingdom; and The Royal Marsden NHS Trust, London SM2 5PT, United Kingdom.
Maria A
MA
Schmidt
CR-UK Cancer Imaging Centre, London SM2 5PT, United Kingdom; The Institute of Cancer Research, London SM2 5PT, United Kingdom; and The Royal Marsden NHS Trust, London SM2 5PT, United Kingdom.
Marco
M
Borri
The Institute of Cancer Research, London SM2 5PT, United Kingdom and The Royal Marsden NHS Trust, London SM2 5PT, United Kingdom.
Dow-Mu
DM
Koh
The Royal Marsden NHS Trust, London SM2 5PT, United Kingdom.
Angela
A
Riddell
The Institute of Cancer Research, London SM2 5PT, United Kingdom and The Royal Marsden NHS Trust, London SM2 5PT, United Kingdom.
Liam
L
Welsh
The Institute of Cancer Research, London SM2 5PT, United Kingdom and The Royal Marsden NHS Trust, London SM2 5PT, United Kingdom.
Alex
A
Dunlop
The Institute of Cancer Research, London SM2 5PT, United Kingdom.
Ceri
C
Powell
The Institute of Cancer Research, London SM2 5PT, United Kingdom and The Royal Marsden NHS Trust, London SM2 5PT, United Kingdom.
Shreerang A
SA
Bhide
The Institute of Cancer Research, London SM2 5PT, United Kingdom and The Royal Marsden NHS Trust, London SM2 5PT, United Kingdom.
Christopher M
CM
Nutting
The Institute of Cancer Research, London SM2 5PT, United Kingdom and The Royal Marsden NHS Trust, London SM2 5PT, United Kingdom.
Kevin J
KJ
Harrington
The Institute of Cancer Research, London SM2 5PT, United Kingdom and The Royal Marsden NHS Trust, London SM2 5PT, United Kingdom.
Kate L
KL
Newbold
CR-UK Cancer Imaging Centre, London SM2 5PT, United Kingdom; The Institute of Cancer Research, London SM2 5PT, United Kingdom; and The Royal Marsden NHS Trust, London SM2 5PT, United Kingdom.
Martin O
MO
Leach
D000328:Adult; D000465:Algorithms; D000792:Angiography; D003287:Contrast Media / Q000493:pharmacokinetics*; D005260:Female; D006258:Head and Neck Neoplasms / Q000000981:diagnostic imaging* / Q000378:metabolism*; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged; D019047:Phantoms, Imaging; D013269:Stochastic Processes
D003287:Contrast Media