Resting-State Functional Connectivity Alterations Associated with Six-Month Outcomes in Mild Traumatic Brain Injury
Eva M Palacios1, Esther L Yuh1,2, Yi-Shin Chang1
11 Department of Radiology and Biomedical Imaging, University of California , San Francisco, California.
Abstract:
Brain lesions are subtle or absent in most patients with mild traumatic brain injury (mTBI) and the standard clinical criteria are not reliable for predicting long-term outcome. This study investigates resting-state functional MRI (rsfMRI) to assess semiacute alterations in brain connectivity and its relationship with outcome measures assessed 6 months after injury. Seventy-five mTBI patients were recruited as part of the prospective multicenter Transforming Research and Clinical Knowledge in TBI (TRACK-TBI) pilot study and compared with matched 47 healthy subjects. Patients were classified following radiological criteria: CT/MRI positive, evidence of lesions; CT/MRI negative, without evidence of brain lesions. rsfMRI data were acquired and then processed using probabilistic independent component analysis. We compared the functional connectivity of the resting-state networks (RSNs) between patients and controls, as well as group differences in the interactions between RSNs, and related both to cognitive and behavioral performance at 6 months post-injury. Alterations were found in the spatial maps of the RSNs between mTBI patients and healthy controls in networks involved in behavioral and cognition processes. These alterations were predictive of mTBI patients' outcomes at 6 months post-injury. Moreover, different patterns of reduced network interactions were found between the CT/MRI positive and CT/MRI negative patients and the control group. These rsfMRI results demonstrate that even mTBI patients not showing brain lesions on conventional CT/MRI scans can have alterations of functional connectivity at the semiacute stage that help explain their outcomes. These results suggest rsfMRI as a sensitive biomarker both for early diagnosis and for prediction of the cognitive and behavioral performance of these patients.
Insights
Resting-state functional MRI (rsfMRI) reveals altered brain connectivity in mild traumatic brain injury (mTBI) patients, even without visible lesions. These connectivity changes predict long-term cognitive and behavioral outcomes.
Area of Science:
- Neuroimaging
- Neurology
- Brain Injury Research
Background:
- Mild traumatic brain injury (mTBI) often lacks visible lesions on standard imaging, making outcome prediction challenging.
- Current clinical criteria for mTBI are insufficient for reliably predicting long-term patient prognosis.
- Resting-state functional MRI (rsfMRI) offers a potential method to detect subtle brain alterations.
Purpose of the Study:
- To investigate semiacute alterations in brain connectivity using rsfMRI in mTBI patients.
- To assess the relationship between these functional connectivity changes and patient outcomes at 6 months post-injury.
- To evaluate rsfMRI as a potential biomarker for mTBI diagnosis and outcome prediction.
Main Methods:
- Seventy-five mTBI patients and 47 healthy controls were recruited for the TRACK-TBI pilot study.
- Patients were categorized as CT/MRI positive (lesions present) or CT/MRI negative (no lesions).
- rsfMRI data were acquired and analyzed using probabilistic independent component analysis to compare resting-state network (RSN) functional connectivity.
Main Results:
- Significant alterations in RSN spatial maps were observed in mTBI patients compared to controls, particularly in networks related to behavior and cognition.
- These rsfMRI-detected connectivity alterations were predictive of cognitive and behavioral outcomes at 6 months post-injury.
- Distinct patterns of reduced network interactions were identified between CT/MRI positive/negative mTBI groups and the control group.
Conclusions:
- rsfMRI can detect functional connectivity alterations in mTBI patients, even in the absence of visible lesions on conventional CT/MRI.
- These semiacute functional connectivity changes are associated with and predictive of long-term cognitive and behavioral outcomes.
- rsfMRI shows promise as a sensitive biomarker for early mTBI diagnosis and predicting patient performance.
