| Autor: |
Delbany, Maya, Bustin, Aurélien, Poujol, Julie, Thomassin‐Naggara, Isabelle, Felblinger, Jacques, Vuissoz, Pierre‐André, Odille, Freddy |
| Zdroj: |
Magnetic Resonance in Medicine; Apr2019, Vol. 81 Issue 4, p2588-2599, 12p |
| Abstrakt: |
Purpose: To quantitatively evaluate a superresolution technique for 3D, one‐millimeter isotropic diffusion‐weighted imaging (DWI) of the whole breasts. Methods: Isotropic 3D DWI datasets are obtained using a combination of (i) a readout‐segmented diffusion‐weighted‐echo‐planar imaging (DW‐EPI) sequence (rs‐EPI), providing high in‐plane resolution, and (ii) a superresolution (SR) strategy, which consists of acquiring 3 datasets with thick slices (3 mm) and 1‐mm shifts in the slice direction, and combining them into a 1 × 1 × 1‐mm3 dataset using a dedicated reconstruction. Two SR reconstruction schemes were investigated, based on different regularization schemes: conventional Tikhonov or Beltrami (an edge‐preserving constraint). The proposed SR strategy was compared to native 1 × 1 × 1‐mm3 acquisitions (i.e. with 1‐mm slice thickness) in 8 healthy subjects, in terms of signal‐to‐noise ratio (SNR) efficiency, using a theoretical framework, Monte Carlo simulations and region‐of‐interest (ROI) measurements, and image sharpness metrics. Apparent diffusion coefficient (ADC) values in normal breast tissue were also compared. Results: The SR images resulted in an SNR gain above 3 compared to native 1 × 1 × 1‐mm3 using the same acquisition duration (acquisition gain 3 and reconstruction gain >1). Beltrami‐SR provided the best results in terms of SNR and image sharpness. The ADC values in normal breast measured from Beltrami‐SR were preserved compared to low‐resolution images (1.91 versus 1.97 ×10–3 mm2/s, P =.1). Conclusion: A combination of rs‐EPI and SR allows 3D, 1‐mm isotropic breast DWI data to be obtained with better SNR than a native 1‐mm isotropic acquisition. The proposed DWI protocol might be of interest for breast cancer monitoring/screening without injection. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
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