Improving the Algorithm for the Management of Patients with Viral Hepatitis Using Contrast-Free Hepatic Arterial Spin Labelling Magnetic Resonance Perfusion

Objective: improving the algorithm for the management of patients with viral hepatitis using contrast-free arterial spin labelling (ASL) magnetic resonance (MR) perfusion.Material and methods. A total of 116 patients with viral hepatitis (VH) B, C and B + C were examined on the basis of Clinical hospital No. 1 (Smolensk): 75 (64.7%) men and 41 (35.3%) women, mean age 49.7 ± 2.3 years. The patients underwent instrumental diagnostic methods: ultrasound, clinical elastography, contrast-free hepatic ASL MR perfusion. Liver biopsy (n = 57) was used as the reference method.Results. The results of ASL MR perfusion had a high correlation with the data of clinical elastography in the diagnosis of fibrotic process; the diagnostic and prognostic significance of ASL liver perfusion in the diagnosis of fibrotic process was: AUROC 0.943 (95% CI, 0.884–0.953). There was a high correlation between ASL MR perfusion with Doppler ultrasound of hepatic blood vessels in the diagnosis of arterial blood flow disorders, but in VH В + C and cirrhosis – diagnostic and prognostic significance of the method: AUROC 0.951 (95% CI 0.932–0.972).Conclusion. ASL MR perfusion in VH patients allows to predict fibrotic changes in the hepatic parenchyma (AUROC 0.934 (95% CI 0.845–0.957)), provides information about changes in blood flow in the parenchymal structure (p < 0.005). The algorithm for the examination of VH patients should include contrast-free ASL MR perfusion at admission (AUROC 0.865 (95% CI 0.843–0.928)) and in dynamic follow-up (AUROC 0.915 (95% CI 0.881–0.946)).

Combined amino acid PET-MRI for identifying recurrence in post-treatment gliomas: together we grow

Purpose The aim of this study is to compare the diagnostic accuracy of amino acid PET, MR perfusion and diffusion as stand-alone modalities and in combination in identifying recurrence in post-treatment gliomas and to qualitatively assess spatial concordance between the three modalities using simultaneous PET-MR acquisition. Methods A retrospective review of 48 cases of post-treatment gliomas who underwent simultaneous PET-MRI using C11 methionine as radiotracer was performed. MR perfusion and diffusion sequences were acquired during the PET study. The following parameters were obtained: TBRmax, TBRmean, SUVmax, and SUVmean from the PET images; rCBV from perfusion; and ADCmean and ADCratio from the diffusion images. The final diagnosis was based on clinical/imaging follow-up and histopathology when available. ROC curve analysis in combination with logistic regression analysis was used to compare the diagnostic performance. Spatial concordance between modalities was graded as 0, 1, and 2 representing discordance, < 50% and > 50% concordance respectively. Results There were 35 cases of recurrence and 13 cases of post-treatment changes without recurrence. The highest area under curve (AUC) was obtained for TBRmax followed by rCBV and ADCratio. The AUC increased significantly with a combination of rCBV and TBRmax. Amino acid PET showed the highest diagnostic accuracy and maximum agreement with the final diagnosis. There was discordance between ADC and PET in 22.9%, between rCBV and PET in 16.7% and between PET and contrast enhancement in 14.6% cases. Conclusion Amino acid PET had the highest diagnostic accuracy in identifying recurrence in post-treatment gliomas. Combination of PET with MRI further increased the AUC thus improving the diagnostic performance.