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Research progress of amide proton transfer imaging in the diagnosis and efficacy evaluation of brain metastases
LI Yuning  WU Dongyang  MAI Li  LI Xiaozhong 

Cite this article as LI Y N, WU D Y, MAI L, et al. Research progress of amide proton transfer imaging in the diagnosis and efficacy evaluation of brain metastases[J]. Chin J Magn Reson Imaging, 2026, 17(8): 161-167. DOI:10.12015/issn.1674-8034.2026.08.018.


[Abstract] Brain metastases (BMs) are common malignant tumors of the central nervous system and severely affect patients' prognosis and quality of life. Therefore, accurate diagnosis and treatment response assessment of BMs are of great significance for clinical management. Amide proton transfer (APT) imaging, as a branch of chemical exchange saturation transfer (CEST) technology, can noninvasively detect intratumoral protein concentration and changes in the metabolic microenvironment, and has shown some potential in studies related to the diagnosis and treatment of central nervous system tumors in recent years. However, current studies on APT imaging in BMs still have several limitations, including relatively small sample sizes, inconsistent scanning parameters and post-processing workflows, differences in APT quantitative metrics and region-of-interest selection, and scattered evidence regarding pathology-related assessment and post-treatment efficacy assessment, and there is a relative lack of systematic reviews specifically focused on BMs. Accordingly, this article reviews the application progress of APT imaging in the differential diagnosis, pathology-related assessment, and post-treatment efficacy assessment of BMs, and discusses its clinical value and future development directions. This review aims to summarize the key evidence and existing challenges of APT imaging in the evaluation of BMs, demonstrate its potential value in improving diagnostic accuracy and post-treatment monitoring of BMs, and provide a reference for future study design and clinical translation.
[Keywords] magnetic resonance imaging；amide proton transfer imaging；brain metastases；chemical exchange saturation transfer imaging；diagnosis

LI Yuning1   WU Dongyang1   MAI Li1   LI Xiaozhong2*  

1 The First Clinical Medical College, Gansu University of Chinese Medicine, Lanzhou 730000, China

2 Department of Radiology, Affiliated Hospital of Gansu University of Chinese Medicine, Lanzhou 730000, China

Corresponding author: LI X Z, E-mail: lixiaozhong925@163.com

Conflicts of interest   None.

Received  2026-04-15
Accepted  2026-07-14
DOI: 10.12015/issn.1674-8034.2026.08.018
Cite this article as LI Y N, WU D Y, MAI L, et al. Research progress of amide proton transfer imaging in the diagnosis and efficacy evaluation of brain metastases[J]. Chin J Magn Reson Imaging, 2026, 17(8): 161-167. DOI:10.12015/issn.1674-8034.2026.08.018.

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