English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Purpose   We present a novel background tissue phase removing method, called anatomical phase extraction (APE), and to investigate the accuracy of temperature estimation and capability of reducing background artifacts compared with the conventional referenceless methods.Methods   Susceptibility variance was acquired by subtracting pretreatment baseline images taken at different locations (nine pretreatment baselines are acquired and called  φ  1  to  φ  9 ). The susceptibility phase data  φ   S   was obtained using the Wiener deconvolution algorithm. The background phase data  φ   T   was isolated by subtracting  φ   S   from the whole phase data. Finally,  φ   T   was subtracted from the whole phase data before applying the referenceless method. As a proof of concept, the proposed APE method was performed on ex vivo pork tenderloin and compared with other two referenceless temperature estimation approaches, including reweighted  ℓ 1 referenceless (RW-  ℓ 1) and  ℓ 2 referenceless methods. The proposed APE method was performed with four different baselines combination, namely, ( φ  1 ,  φ  5 ,  φ  2 ,  φ  4 ), ( φ  3 ,  φ  5 ,  φ  2 ,  φ  6 ), ( φ  7 ,  φ  5 ,  φ  8 ,  φ  4 ), and ( φ  9 ,  φ  5 ,  φ  8 ,  φ  6 ), and called APE experiment 1 to 4, respectively. The multibaseline method was used as a standard reference. The mean absolute error (MAE) and two-sample  t -test analysis in temperature estimation of three regions of interest (ROI) between the multibaseline method and the other three methods, i.e., APE, RW-  ℓ 1, and  ℓ 2, were calculated and compared.Results   Our results show that the mean temperature errors of the APE method-experiment 1, APE method-experiment 2, APE method-experiment 3, APE method-experiment 4, and RW-  ℓ 1 and  ℓ 2 referenceless method are 1.02°C, 1.04°C, 1.00°C, 1.00°C, 4.75°C, and 13.65°C, respectively. The MAEs of the RW-  ℓ 1 and  ℓ 2 referenceless methods were higher than that of APE method. The APE method showed no significant difference ( p  > 0.05), compared with the multibaseline method.Conclusion   The present work demonstrates the use of the APE method on referenceless MR thermometry to improve the accuracy of temperature estimation during MRI guided high-intensity focused ultrasound for ablation treatment.

computational and mathematical methods in medicine

Anatomical Phase Extraction (APE) Method: A Novel Method to Correct Detrimental Effects of Tissue-Inhomogeneity in Referenceless MR Thermometry—Preliminary Ex Vivo Investigation