Stability of R2* and quantitative susceptibility mapping of the brain tissue in a large scale multi-center study

Abstract

Multi-center studies are advantageous for enrolling participants of varying pathological and demographical conditions, and especially in neurological studies. Hence stability of the obtained quantitative R2* and susceptibility in multicenter studies is a key issue for their widespread applications. In this work, the stabilities of simultaneously obtained R2* and susceptibility are investigated and compared across 10 sites that are equipped with the same scanner and receiver coil, the same post-processing process was used to achieve consistent experiment setup. Two healthy adult volunteers (one male and female) participated in this study. High intraclass correlation coefficient was obtained for both susceptibility (0.94) and R2* (0.96). The coefficients of variance for all measurements obtained were smaller than 0.1, the largest variations of measurements in all the chosen ROIs fall within ±20% from the median value. Higher level of stability was obtained in R2* as compared to susceptibility at 1 mm resolution (P < 0.05) and at 1.5 mm (P < 0.01).

Distinct progression pattern of susceptibility MRI in the substantia nigra of Parkinson's patients

“…We found QSM is higher in the SN only in middle‐ and later‐stage patients, consistent with reports that increased iron is observed in advanced‐stage PD patients . However, our study did not detect significant longitudinal changes in QSM, possibly because QSM is less stable than R2* despite having a better signal for iron . The fact that R2* changes in the SNc persisted even after adjusting for QSM suggests that R2* may capture, in addition to iron, the complex microstructural changes occurring during PD progression.…”

Measurements of cerebral blood volume using quantitative susceptibility mapping, R2* relaxometry, and ferumoxytol‐enhanced MRI

“…The variance in the QSM‐based CBV estimates was larger than that using the R 2 * method, but the average and median values were similar to R 2 *‐based estimates in GM and WM. A recent report from a multi‐center study showed higher stability in R 2 * than in QSM susceptibility measurements in brain mapping applications . That finding correlates well with our observations.…”

“…The variability found between QSM solvers and QSM‐based measures in this and other studies make the R 2 *‐based CBV method the recommended approach for CBV estimates, although in theory QSM approaches provide a more direct relationship to contrast agent concentration than R 2 * mapping and are less prone to artifacts that can vary with image parameters. This should continue to serve as motivation for development of improved QSM algorithms.…”

Cerebral OEF quantification: A comparison study between quantitative susceptibility mapping and dual‐gas calibrated BOLD imaging

“…Another limitation of this study is the lack of test‐retest reliability analysis of the presented techniques. Nevertheless, previous studies found that QSMs have excellent reproducibility on intrascanner and interscanner acquisitions . In addition, previous studies exploring microvascular QSM‐OEF using hyperventilation found good reproducibility between 2 repeated hyperventilation challenges: Bland‐Altman plots revealed no statistically significant bias between the 2 sessions.…”

“…Nevertheless, previous studies found that QSMs have excellent reproducibility on intrascanner and interscanner acquisitions. [59][60][61][62] In addition, previous studies exploring microvascular QSM-OEF using hyperventilation found good reproducibility between 2 repeated hyperventilation challenges 11 : Bland-Altman plots revealed no statistically significant bias between the 2 sessions. Therefore, we believe that it is reasonable to infer that our hypercapnic QSM-OEF results would have very good intrasubject reproducibility.…”