Segmented 3D Echo Planar Acquisition for Rapid Susceptibility-Weighted Imaging: Application to Microhemorrhage Detection in Traumatic Brain Injury

Wen-Tung Wang; Ningzhi Li; Ioannis Papageorgiou; Leighton Chan; Dzung L Pham; John A Butman

doi:10.1002/jmri.28326

Segmented 3D Echo Planar Acquisition for Rapid Susceptibility-Weighted Imaging: Application to Microhemorrhage Detection in Traumatic Brain Injury

J Magn Reson Imaging. 2022 Nov;56(5):1529-1535. doi: 10.1002/jmri.28326. Epub 2022 Jul 19.

Authors

Wen-Tung Wang^{1

2}, Ningzhi Li³, Ioannis Papageorgiou⁴, Leighton Chan^{2

5}, Dzung L Pham^{1

2

6}, John A Butman^{1

2}

Affiliations

¹ Radiology and Imaging Sciences, Clinical Center, NIH, Bethesda, Maryland, USA.
² Center for Neuroscience and Regenerative Medicine, Bethesda, Maryland, USA.
³ Center for Devices and Radiological Health, FDA, Silver Spring, Maryland, USA.
⁴ Magnitiki Tomografia of Epirus-Diagnostic MRI Center, Ioannina, Greece.
⁵ Rehabilitation Medicine Department, Clinical Center, NIH, Bethesda, Maryland, USA.
⁶ Uniformed Services University of the Health Sciences, Bethesda, Maryland, USA.

Abstract

Background: Susceptibility-weighted imaging (SWI) provides superior image contrast of cerebral microhemorrhages (CMBs). It is based on a three-dimensional (3D) gradient echo (GRE) sequence with a relatively long imaging time.

Purpose: To evaluate whether an accelerated 3D segmented echo planar imaging SWI is comparable to GRE SWI in detecting CMBs in traumatic brain injury (TBI).

Study type: Prospective.

Subjects: Four healthy volunteers and 46 consecutive subjects (38.0 ± 14.4 years, 16 females; 12 mild, 13 moderate, and 7 severe TBI).

Field strength/sequence: A 3 T scanner/3D gradient echo and 3D segmented echo planar imaging (segEPI).

Assessment: Brain images were acquired using GRE and segEPI in a single session (imaging time = 9 minutes 47 seconds and 1 minute 30 seconds, respectively). The signal-to-noise ratio (SNR) calculated from healthy volunteer thalamus and centrum semiovale were compared. CMBs were counted by three raters blinded to diagnostic information.

Statistical tests: A t-test was used to assess SNR difference. Pearson correlation and Wilcoxon signed-rank test were performed using CMB counts. The intermethod agreement was evaluated using Bland-Altman method. Intermethod and interrater reliabilities of image-based diffuse axonal injury (DAI) diagnoses were evaluated using Cohen's kappa and percent agreement. P ≤ 0.05 was considered statistically significant.

Results: Thalamus SNRs were 16.9 ± 2.2 and 16.5 ± 3 for GRE and segEPI (P = 0.84), respectively. Centrum semiovale SNRs were 25.8 ± 4.6 and 21.1 ± 2.7 (P = 0.13). The correlation coefficient of CMBs was 0.93, and differences were not significant (P = 0.56-0.85). For DAI diagnoses, Cohen's kappa was 0.62-0.84 and percent agreement was 85%-94%.

Data conclusion: CMB counts on segEPI and GRE were highly correlated, and DAI diagnosis was made equally effectively. segEPI SWI can potentially replace GRE SWI in detecting TBI CMBs, especially when time constraints are critical.

Evidence level: 1 TECHNICAL EFFICACY: Stage 2.

Keywords: diffuse axonal injury; echo planar imaging; microbleed; microhemorrhage; susceptibility-weighted imaging; traumatic brain injury.

Published 2022. This article is a U.S. Government work and is in the public domain in the USA. Journal of Magnetic Resonance Imaging published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine.

Publication types

Research Support, N.I.H., Intramural
Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

Brain Injuries, Traumatic* / complications
Brain Injuries, Traumatic* / diagnostic imaging
Diffuse Axonal Injury*
Echo-Planar Imaging / methods
Female
Humans
Magnetic Resonance Imaging / methods
Prospective Studies

Abstract

Publication types

MeSH terms

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