Abstract
Objectives
This study aimed to examine the equivalence of computed tomography (CT)–based synthetic T1-weighted imaging (T1WI) to conventional T1WI for the quantitative assessment of brain morphology.
Materials and methods
This prospective study examined 35 adult patients undergoing brain magnetic resonance imaging (MRI) and CT scans. An image synthesis method based on a deep learning model was used to generate synthetic T1WI (sT1WI) from CT data. Two senior radiologists used sT1WI and conventional T1WI on separate occasions to independently measure clinically relevant brain morphological parameters. The reliability and consistency between conventional and synthetic T1WI were assessed using statistical consistency checks, comprising intra-reader, inter-reader, and inter-method agreement.
Results
The intra-reader, inter-reader, and inter-method reliability and variability mostly exhibited the desired performance, except for several poor agreements due to measurement differences between the radiologists. All the measurements of sT1WI were equivalent to that of T1WI at 5% equivalent intervals.
Conclusion
This study demonstrated the equivalence of CT-based sT1WI to conventional T1WI for quantitatively assessing brain morphology, thereby providing more information on imaging diagnosis with a single CT scan.
Clinical relevance statement
Real-time synthesis of MR images from CT scans reduces the time required to acquire MR signals, improving the efficiency of the treatment planning system and providing benefits in the clinical diagnosis of patients with contraindications such as presence of metal implants or claustrophobia.
Key Points
• Deep learning–based image synthesis methods generate synthetic T1-weighted imaging from CT scans.
• The equivalence of synthetic T1-weighted imaging and conventional MRI for quantitative brain assessment was investigated.
• Synthetic T1-weighted imaging can provide more information per scan and be used in preoperative diagnosis and radiotherapy.
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Abbreviations
- AIS:
-
Acute ischemic stroke
- BAHLV:
-
Angle formed by the bilateral anterior horns of the lateral ventricles
- BPHLV:
-
Angle formed by the bilateral posterior horns of the lateral ventricles
- CT:
-
Computed tomography
- CTLCC:
-
Cortical thickness of the left cingulate cortex
- CTRCC:
-
Cortical thickness of the right cingulate cortex
- DKCCPP:
-
Distance between knee of the corpus callosum and pressing part
- GAN:
-
Generative adversarial network
- HCC:
-
Height of the corpus callosum
- ICC:
-
Intra-class correlation coefficient
- IH:
-
Intracranial height
- IL:
-
Intracranial length
- IW:
-
Intracranial width
- LEL:
-
Left eyeball length
- LEW:
-
Left eyeball width
- LLVAAD:
-
Left lateral ventricle anteroposterior angle distance
- LTL:
-
Left thalamus length
- LTW:
-
Left thalamus width
- MPR:
-
Multi-planar reconstruction
- MRI:
-
Magnetic resonance imaging
- PL:
-
Pontine length
- PW:
-
Pontine width
- REL:
-
Right eyeball length
- REW:
-
Right eyeball width
- RLVAAD:
-
Right lateral ventricle anteroposterior angle distance
- RTL:
-
Right thalamus length
- RTW:
-
Right thalamus width
- sMRI:
-
Synthetic magnetic resonance imaging
- sT1WI:
-
Synthetic T1-weighted image
- TPS:
-
Treatment planning system
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Acknowledgements
We thank the Institute of Medical Technology, Peking University Health Science Center for technical support and Shenzhen Second People’s Hospital for data collection.
Funding
This work was supported by the National Natural Science Foundation of China (Grant No. 12075011, No. 82071280, and No. 82171913), the Natural Science Research of Jiangsu Higher Education Institutions of China (No. 23KJB310019), and the Key Research and Development Program of Science and Technology Planning Project of Tibet Autonomous Region, China (Grant No. XZ202001ZY0005G).
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All authors contributed to the study conception and design. Material preparation, data collection, and analysis were performed by Zhaotong Li, Gan Cao, Li Zhang, and Jichun Yuan. The first draft of the manuscript was written by Zhaotong Li and Gan Cao, and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.
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The scientific guarantor of this publication is Dr. Jun Xia.
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The authors of this manuscript declare no relationships with any companies, whose products or services may be related to the subject matter of the article.
Statistics and biometry
No complex statistical methods were necessary for this paper.
Informed consent
Written informed consent was obtained from all subjects (patients) in this study.
Ethical approval
This study was performed in line with the principles of the Declaration of Helsinki. The study’s protocol was also approved by the local medical ethics committee of Shenzhen Second People’s Hospital.
Study subjects or cohorts overlap
No study subjects or cohorts have been previously reported.
Methodology
• prospective
• cross-sectional study/observational study
• multi-center study
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Li, Z., Cao, G., Zhang, L. et al. Feasibility study on the clinical application of CT-based synthetic brain T1-weighted MRI: comparison with conventional T1-weighted MRI. Eur Radiol (2024). https://doi.org/10.1007/s00330-023-10534-1
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DOI: https://doi.org/10.1007/s00330-023-10534-1