Improved reliability of resting-state functional MRI connectivity using multi-echo acquisition: Implications for personalized transcranial magnetic stimulation targeting

Authors

• Elmira Hassanzadeh, Harvard Medical School
• Rabeet Tariq, Aga Khan UniversityFollow
• Stephan Palm, Harvard Medical School
• Nicole Chiulli, Harvard Medical School
• David Lawson, Harvard Medical School
• Sanaz Khosravani, Harvard Medical School
• Tracy Barbour, Massachusetts General Hospital
• Ru Kong, Harvard Medical School
• B T Thomas Yeo, Harvard Medical School
• Michael D. Fox, Brigham and Women's Hospital
• Shan H. Siddiqi, Harvard Medical School

Document Type

Article

Department

Surgery

Abstract

Background and purpose: Multi-echo (ME) functional MRI (fMRI) acquisition improves separation of signal from noise relative to single-echo (SE). We tested whether this enhances reliability of functional connectivity (FC), with a focus on personalizing transcranial magnetic stimulation (TMS) targets in the dorsolateral prefrontal cortex (DLPFC) in patients with depression.
Materials and methods: Resting-state fMRI scans were acquired from adult patients with major depression (20 female, 15 male) presenting for clinical TMS using either SE (n=21) or ME (n=31). Each subject's fMRI timeseries was split in half, and voxel-wise seed-based FC was computed for 100 general regions of interest (ROIs) and for two TMS-specific ROIs: subgenual cingulate cortex (SGC) and a previously published depression circuit (DEP). Reliability was assessed using (1) spatial correlation between split-half connectivity maps and (2) intraclass correlation coefficient (ICC) for each ROI's connectivity to the DLPFC.
Results: In general ROI analysis, ME showed significantly higher whole-brain split-half correlations than SE (p = 0.006) and higher ICC (ΔICC = 0.16; p = 0.03). In TMS-specific ROI analysis, ME showed higher split-half correlations for both the SGC-DLPFC (p = 0.04) and DEP-DLPFC (p = 0.01). TMS-specific ICC values were numerically higher for ME (SGC-DLPFC: 0.47; DEP-DLPFC: 0.75) than for SE (0.02 and 0.40, respectively), although these differences were not statistically significant.
Conclusion: ME fMRI improves general FC reliability over SE, with suggested advantages for TMS-specific measures. Future work is needed to determine whether these gains meaningfully improve TMS targeting.

Comments

Volume, issue and pagination are not provided by the author/publisher.

Publication (Name of Journal)

American Journal of Neuroradiology

DOI

10.3174/ajnr.A9301

Recommended Citation

Hassanzadeh, E., Tariq, R., Palm, S., Chiulli, N., Lawson, D., Khosravani, S., Barbour, T., Kong, R., Yeo, B. T., Fox, M. D., Siddiqi, S. H. (2026). Improved reliability of resting-state functional MRI connectivity using multi-echo acquisition: Implications for personalized transcranial magnetic stimulation targeting. American Journal of Neuroradiology.
Available at: https://ecommons.aku.edu/pakistan_fhs_mc_surg_neurosurg/435