Abstract
PURPOSE: Cerebral venous oxygenation (Y(v)) is an important physiological parameter and has potential clinical application in many brain diseases. T(2)-relaxation-under-spin-tagging (TRUST) is a commonly used MRI method to measure Y(v). Harmonization of this technique across MRI vendors is important for dissemination and multi-center 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-hour period. On each scanner, the subject was scanned in two sessions to assess inter-session reproducibility. A hyperoxia challenge was also included in both sessions and on both scanners to evaluate the sensitivity of the technique to Y(v) changes. Measured Y(v) values, confidence interval of Y(v) estimates (ε(Y(v))), as well as intra-session and inter-session coefficient of variation (CoV) of Y(v), were compared between the two scanners. RESULTS: Y(v) measured on the two vendors were highly compatible and strongly correlated (R(2)=0.957). Y(v) changes associated with hyperoxia challenge were significant on both scanners (P<0.001) and were also correlated across scanners (P=0.007). Intra-session and inter-session CoV of measured Y(v) were less than 3% and showed no difference between scanners. ε(Y(v)) 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 Y(v) measurements across different vendors.