Linna Li1, Zhongping Chen1, Renjie Lu2, Xin He1, Ying Qiu1, Dandan Guo1, Hongkun Shi1, Dan Tong1, Yi Zhu3, and Ke Jiang3
1Radiology, The First Hospital of Jilin Universty, Changchun, China, 2Ultrasound, The First Hospital of Jilin Universty, Changchun, China, 3Philips Healthcare, Beijing, China
Synopsis
Contrast-enhanced
(CE) 3D T1-weighted scanning has been used more frequently with better spatial resolution and thinner section than 2D T1-weighted images
for early detection and response assessment of brain metastases. To further improve the image scanning
sequence, a new reconstruction algorithm, Compressed-SENSE Artificial
Intelligence (CS-AI) was applied experimentally to achieve a balance between shortened
scan time and improved image quality. This study aims to
investigate the feasibility of contrast-enhanced 3D T1-weighted MRI reconstructed
with Compressed SENSE Artificial Intelligence (CS-AI) by comparing with 3D T1-weighted
images reconstructed with Compressed SENSE(CS), and to find out the optimal acceleration factor(AF).
Introduction
Brain metastases (BM) as secondary brain neoplasms
are the most common type of brain tumors in adults1-2. Early detection of
brain metastases has become an important determinant of both survival time and
quality of life for cancer patients. Contrast-enhanced 3D T1-weighted scanning
shows higher sensitivity than 2D T1-weighted enhanced scanning for the
detection of small brain metastases and has been used more frequently for the
evaluation of brain metastases3-4. However,
the long acquisition time of 3D sequence limits its use in clinical settings. Compressed
SENSE (CS) has been validated as an efficient acceleration technique which may
reduce the acquisition time and artifact of pulsation. More recently, deep
learning framework have been combined with CS to overcome these challenges by
learning optimal reconstruction parameters from the data itself and showed
superior performance5.Purpose
The purpose of this study
was to acquire highly accelerated 3D T1-weighted imaging using the
Compressed-SENSE Artificial Intelligence (CS-AI) framework reconstruction and to evaluate the image quality of CS-AI with different high acceleration
factors (AF) compared with CS technique.Methods
This
study was approved by the institutional review board of the first hospital of Jilin
University, and written informed consent was obtained from all subjects. A
total of 14 patients who were suspected of metastatic lesions were examined on
a 3.0T MR system (Ingenia Elition X, Philips Healthcare). All patients
received different customized 3D T1-weighted sequences which included different
AF sequences utilizing CS (CS6, CS8, CS10, CS12) and CS-AI technology (CS-AI8,
CS-AI10, CS-AI12) in
random order. Among them, CS6 is a commercially available standard
sequence and is shown as a reference. The
parameters for 3D T1-weighted were: TR=600ms; TE=28ms; FOV=250×250mm, 327 slices, voxel
size=0.99×1.00×1.10mm. The
total scanning time of post-contrast
3D TI-weighted
reconstructed with CS6, CS/CS-AI-8, CS/CS-AI-10, CS/CS-AI12 were 3:34min, 2:42min, 2:10min and 1:49min, respectively. Quantitative
image analysis was performed by two radiologists with more than 5 years of
experience. (Figure1-3) ROIs were
placed on lesions and white matters. Based on the ROIs, Signal-to-noise ratio
(SNR) and contrast-to-noise ratio (CNR) were analyzed for objective evaluation with
the following formula:
$$SNR_{lesion}=\frac{SI_{lesion}}{SD_{lesion}}$$ [1]
$$CNR_{lesion-white matter}=\frac{|SI_{lesion}-SI_{white matter}|}{\sqrt{SD_{lesion}^{2}+SD_{white matter}^{2}}}$$ [2]
One-way repeated-measures analysis of variance (ANOVA) and
post hoc Tukey test were used for statistical analysis by Graphpad 9.0. Values
of P < 0.05 were considered statistically significant.
Results and Discussion
There was no
significant difference of SNRs observed between CS-AI and CS for any AF(all P>0.05)
(Figure4). The CNRs of CS-AI8 and CS-AI10 were significantly higher than those
acquired with reference CS6 (P<0.05), and no significant difference was
found in CNR between CS-AI12 and reference CS6
(P>0.05). Moreover, the CNR values of CS-AI8 and CS-AI10 were higher than
that of CS scans at the same AF(Both P<0.05). Additionally, the image
quality of CS-AI with AF 8 was similar to 10. It showed degradation of image quality
with AF
12 due to insufficient noise removal, while the image quality with AF
8 and 10 showed better performance (Figure5). AF 8 has slight advantage in the
presentation of lesion details, whereas AF 10 can save more time.Conclusion
3D T1-weighted
sequence reconstructed with CA-AI at 3.0 T in detection of brain metastases may
provide an effective, alternative reconstruction approach to CS. We suggest
that acceleration factor 10 is more suitable for clinical application with the
optimal image quality and shortened time.Acknowledgements
No acknowledgement found.References
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