Τίτλος:
Apparent diffusion coefficient measurements on a novel diffusion weighted MRI phantom utilizing EPI and HASTE sequences
Γλώσσες Τεκμηρίου:
Αγγλικά
Περίληψη:
Purpose: The aim of this study is to introduce a novel DWI-MRI phantom and to compare Apparent Diffusion Coefficient (ADC) measurements, utilizing EPI-DWI and HASTE-DWI sequences and two different fitting algorithms. Materials and Methods: 23 test tubes with different sucrose concentrations and polyacrylamide gels were used as a phantom for ADC measurements. The phantom was scanned on a clinical MRI system (1.5 T) over a two-month period utilizing an EPI-DWI and a HASTE-DWI sequence. ADC maps were calculated using a Weighted Linear (WL) and a Non Linear (NL) fitting algorithm. Measurements were performed with two sequences and two fitting algorithms. Geometric Distortions (GD), Ghosting Ratios (GR) and Signal to Structured Noise Ratios (SSNRs) were estimated using both sequences from the resultant ADC parametric maps. Results: Polyacrylamide gels reveal lower coefficient of variation (CV%) as compared to sucrose solutions. ADC measurements performed with WL and NL algorithms reveal identical results with both sequences. WL and NL algorithms require approx. 3 s and 7 min respectively, for a single slice. EPI-DWI reveals a mean percent ADC value difference of (+4.5%) as compared to HASTE-DWI, regardless the type of fitting algorithm. Conclusion: Polyacrylamide gels can serve as a better means for simulating ADC values, compared with sucrose solutions used in this study. WL can be proposed as the method for ADC measurements in daily clinical practice. WL is significantly faster than NL fitting method and equally precise. SSNR measured directly on ADC maps is an excellent means for testing the precision of ADC measurements. © 2020 Associazione Italiana di Fisica Medica
Συγγραφείς:
Kalaitzakis, G.
Boursianis, T.
Gourzoulidis, G.
Gourtsoyianni, S.
Lymperopoulou, G.
Marias, K.
Karantanas, A.
Maris, T.G.
Περιοδικό:
PHYSICA MEDICA-EUROPEAN JOURNAL OF MEDICAL PHYSICS
Εκδότης:
Associazione Italiana di Fisica Medica
Λέξεις-κλειδιά:
polyacrylamide gel; sucrose, accuracy; apparent diffusion coefficient; Article; clinical practice; concentration (parameter); controlled study; diffusion weighted imaging; echo planar imaging; Geometric Distortion; Ghosting Ratio; Half Fourier Acquisitions Single shot Turbo spin Echo; imaging algorithm; magnetic field; Non Linear fitting algorithm; radiological parameters; Signal to Structured Noise Ratio; Weighted Linear fitting algorithm; devices; diffusion weighted imaging; imaging phantom; statistical model, Diffusion Magnetic Resonance Imaging; Linear Models; Phantoms, Imaging
DOI:
10.1016/j.ejmp.2020.04.024
