Relaxation-enhanced angiography without contrast and triggering can be used for renal artery angiography

ZHONG Zhiming; JIANG Jieying; CHEN Peng; LIU Tiejun; PAN Hui

doi:10.12122/j.issn.1674-4500.2025.03.06

Abstract：Objective To evaluate the feasibility of using relaxation-enhanced angiography without contrast and triggering(REACT)for renal artery angiography.Methods Thirty patients who visited International Zhuang Hospital Affiliated to Guangxi University of Chinese Medicine from August 2023 to October 2024 were included as prospective study.All patients were scaned by contrast-enhanced magnetic resonance angiography(CE MRA)sequence,balanced gradient echo sequence(BTFE)and REACT sequence,respectively.The overall image quality score of three sets were compared.The ratio of minimum to maximum signal intensity,signal to noise ratio and contrast to noise ratio of the main renal artery and left and right branch were calculated.The differences of the ratio of minimum to maximum signal intensity,signal to noise ratio and contrast to noise ratio among the three groups were compared.The consistency of the image quality scores was assessed by the Kappa test.Results The consistency of image quality scores given by two physicians for the three groups was evaluated as good(Kappa values=0.82,0.70,0.55).The average overall image quality scores for the CE MRA group,BTFE group,and REACT group were 3.48,3.05,2.18,respectively.No significant difference was observed between the CE MRA group and the BTFE group(P=0.06),whereas significant differences were noted in all other comparisons(P<0.05).The average RSI of the renal artery was found to be highest in the CE MRA group,followed by the REACT group,and subsequently the BTFE group.Statistically significant differences were observed in pairwise comparisons(P<0.05).The mean SNR and CNR for both the main renal artery and its left and right branches were highest in the BTFE group,followed by the CE MRA group,with the REACT group showing lower values;these differences also reached statistical significance in pairwise comparisons(P<0.05).Conclusion The BTFE sequence demonstrates an effective capability to visualize the main renal artery and its branches without necessitating a gadolinium contrast agent.Its display performance is comparable to that of CE MRA sequences while significantly outperforming that of REACT sequences.However,it should be noted that when severely impacted by factors such as breath-holding duration or breathing regularly,the REACT sequence may serve as a more suitable compensatory method for non-contrast renal artery angiography.