Cross-vendor harmonization of T 2 -relaxation-under-spin-tagging (TRUST) MRI for the assessment of cerebral venous oxygenation.

PURPOSE: Cerebral venous oxygenation (Yv ) is an important physiological parameter and has potential clinical application in many brain diseases. T2 -relaxation-under-spin-tagging (TRUST) is a commonly used MRI method to measure Yv . Harmonization of this technique across MRI vendors is important for dissemination and multicenter studies of brain oxygenation and metabolism as a disease biomarker.

METHODS: TRUST pulse sequence components and imaging parameters were carefully matched between two major MRI vendors, Philips and Siemens. Each subject (N = 10) was scanned on both scanners within a 2.5-h period. On each scanner, the subject was scanned in two sessions to assess intersession reproducibility. A hyperoxia challenge was also included in both sessions and on both scanners to evaluate the sensitivity of the technique to Yv changes. Measured Yv values, confidence interval of Yv estimates ( εYv), as well as intrasession and intersession coefficient of variation (CoV) of Yv , were compared between the two scanners.

RESULTS: Yv measured on the two vendors were highly compatible and strongly correlated (R2  = 0.957). Yv changes associated with hyperoxia challenge were significant on both scanners (P < 0.001) and were also correlated across scanners (P = 0.007). Intrasession and intersession CoV of measured Yv were less than 3% and showed no difference between scanners. εYv were less than 1% on both scanners and showed no difference between scanners when echo times were matched on the two scanners.

CONCLUSION: This work suggests that harmonized TRUST MRI can yield highly compatible Yv measurements across different vendors. Magn Reson Med 80:1125-1131, 2018. © 2018 International Society for Magnetic Resonance in Medicine.