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Objective To compare the image quality of carotid contrast-enhanced magnetic resonance angiography(ceMRA)under different flow rates using high relaxation rate contrast agent named Gadobutrol,and to find the best flow rate for carotid ceMRA.Methods Total of 117 patients,who were scheduled to perform carotid ceMRA examination using Gadobutrol with a dosage of 0.1 mL/kg body weight on a 1.5T MR platform,were enrolled in the study.They were divided into four groups according to four kinds of flow rates,which were 1.0 mL/s(n=29),1.5 mL/s(n=30),2.0 mL/s(n=30)and 3.0 mL/s(n=28).The signal-to-noise ratio(SNR)of bilateral carotid initiation and bilateral carotid bifurcation were calculated.The SNR of carotid initiation or carotid bifurca-tion between different flow rates were compared.And the scores of image quality among different flow rates were also compared.Results For bilateral carotid bifurcations and carotid initiations,the SNR under 1.5 mL/s were highest,which were significantly higher than those under 1.0 mL/s,while there were no significant differences between each two other flow rates.For the bilateral carotid bifurca-tions,the SNR under 1.0 mL/s were lower than those under other flow rates,and were significantly lower than those under 1.5 mL/s and 3.0 mL/s.The score of the image quality at 1.0 mL/s was significantly lower than that under other flow rates.The score of the image quality at 1.5 mL/s was the highest,but no significant difference was found compared to that at 2.0 mL/s or 3.0 mL/s.Conclusion The rate of 1.5 mL/s is recommended as the best flow rate for carotid ceMRA with Gadobutrol based on 1.5T MR.
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BACKGROUND:Studies have shown that pathological change of substantia nigra (SN) is the main reason for Parkinson's disease (PD).From the medical imaging,spatial location,size and 3D morphology analysis of the tiny SN structure are very important to PD's diagnosis and treatment evaluation.As the physiology of rhesus monkey is much similar to human's,it has been used as an ideal experiment subject in many scientific researches.OBJECTIVE:To modify traditional shape-based interpolation method for SN structure of the rhesus monkey brain slices.METHODS:To gain the middle layers between two slices,traditional shape-based interpolation used linear weighted mean algorithm.However,considering the impact of adjacent multi-layer to the image,the middle layers were obtained by non-linear weight.RESULTS AND CONCLUSION:The new interpolation algorithm was assessed with a favorable results.Also,this method was applied to the 3D reconstruction of SN structure.The results show that the new interpolation method can be used in nucleus group interpolation with sparse slices and tiny structures,and offer reference to the related disease research.