Reliability of Task-Based fMRI for Preoperative Planning: A Test-Retest Study in Brain Tumor Patients and Healthy Controls

Abstract

BackgroundFunctional magnetic resonance imaging (fMRI) continues to develop as a clinical tool for patients with brain cancer, offering data that may directly influence surgical decisions. Unfortunately, routine integration of preoperative fMRI has been limited by concerns about reliability. Many pertinent studies have been undertaken involving healthy controls, but work involving brain tumor patients has been limited. To develop fMRI fully as a clinical tool, it will be critical to examine these reliability issues among patients with brain tumors. The present work is the first to extensively characterize differences in activation map quality between brain tumor patients and healthy controls, including the effects of tumor grade and the chosen behavioral testing paradigm on reliability outcomes.MethodTest-retest data were collected for a group of low-grade (n = 6) and high-grade glioma (n = 6) patients, and for matched healthy controls (n = 12), who performed motor and language tasks during a single fMRI session. Reliability was characterized by the spatial overlap and displacement of brain activity clusters, BOLD signal stability, and the laterality index. Significance testing was performed to assess differences in reliability between the patients and controls, and low-grade and high-grade patients; as well as between different fMRI testing paradigms.ResultsThere were few significant differences in fMRI reliability measures between patients and controls. Reliability was significantly lower when comparing high-grade tumor patients to controls, or to low-grade tumor patients. The motor task produced more reliable activation patterns than the language tasks, as did the rhyming task in comparison to the phonemic fluency task.ConclusionIn low-grade glioma patients, fMRI data are as reliable as healthy control subjects. For high-grade glioma patients, further investigation is required to determine the underlying causes of reduced reliability. To maximize reliability outcomes, testing paradigms should be carefully selected to generate robust activation patterns.

Methodological considerations in assessment of language lateralisation with fMRI: a systematic review

“…However, the majority of studies report higher reproducibility for signal magnitude measures compared to signal extent measures (Adcock et al, 2003; Jansen et al, 2006; Harrington, Buonocore & Farias, 2006; Morrison et al, 2016). Importantly, Jansen et al (2006) reported that a magnitude measure determined dominance reproducibly only when just those voxels that exceeded a criterion activation level were included; an extent measure was not reproducible.…”

Optimization of fMRI methods to determine laterality of cortical activation during ankle movements of children with unilateral cerebral palsy

“…The LI was calculated based on suprathreshold voxel count (i.e., extent) rather than intensity of activation. The reproducibility and robustness of both methods have been tested and debated (Jansen et al, 2006; Morrison et al, 2016; Seghier, 2008). The extent approach used is more appropriate for large region of interests (ROIs) (Jansen et al, 2006), allowing for inter‐individual variability in morphology and in activation location as is possible for children with UCP (Wittenberg, 2009).…”

“…The spatial overlap between runs was determined by masking LI datasets of run 1 with subsequent runs for each leg. The total number of activated voxels were counted for each run (V Run1 ; V Run2 ), and then the number of commonly activated voxels were determined (V overlap ) using a Dice coefficient (Dice, 1945; Morrison et al, 2016) according to the following formula:…”

Repeatability of language fMRI lateralization and localization metrics in brain tumor patients

“…SWG task activates mainly frontal lobe language and cognitive support areas but are less consistent activators of temporal language regions (Pillai & Zaca, ; Zaca et al, ; Zaca, Jarso, & Pillai, ). These tasks are often repeated to confirm the reproducibility of activations (Carp, ; Fernández et al, ; Harrington, Buonocore, & Tomaszewski Farias, ; Maïza et al, ; Morrison et al, ; Poline, Strother, Dehaene‐Lambertz, Egan, & Lancaster, ; Rutten, Ramsey, van Rijen, & van Veelen, ; Voyvodic, ). Previous validation studies evaluated across‐subject reproducibility; however, within‐subject repeatability in the same scan session for reproducibility of language lateralization and localization has not yet been comprehensively validated.…”

“…In general, reliability metrics are used to quantify test–retest variability of activation clusters across sessions and across subjects (Gorgolewski, Storkey, Bastin, Whittle, & Pernet, ; Otzenberger, Gounot, Marrer, Namer, & Metz‐Lutz, ; Raemaekers, Du Plessis, Ramsey, Weusten, & Vink, ). Previous studies reported varied results due to the varied statistical methods used to quantify test–retest reliability (Chen & Small, ; Fesl et al, ; Morrison et al, ). The majority of studies used correlation coefficients as a prominent measure of reliability which informs about the consistency of activation between subjects (Caceres, Hall, Zelaya, Williams, & Mehta, ; Maldjian, Laurienti, Driskill, & Burdette, ; Stevens, Clarke, Stroink, Beyea, & D'Arcy, ).…”