Dataset Information

Automated Assessment of Cerebral Arterial Perforator Function on 7T MRI.

ABSTRACT:

Background

Blood flow velocity and pulsatility of small cerebral perforating arteries can be measured using 7T quantitative 2D phase contrast (PC) MRI. However, ghosting artifacts arising from subject movement and pulsating large arteries cause false positives when applying a previously published perforator detection method.

Purpose

To develop a robust, automated method to exclude perforators located in ghosting artifacts.

Study type

Retrospective.

Subjects

Fifteen patients with vascular cognitive impairment or carotid occlusive disease and 10 healthy controls.

Field strength/sequence

7T/cardiac-gated 2D PC MRI.

Assessment

Perforators were automatically excluded from ghosting regions, which were defined as bands in the phase-encoding direction of large arteries. As reference, perforators were manually excluded by two raters (T.A., J.J.M.Z.), based on perforator location with respect to visible ghosting artifacts. The performance of both censoring methods was assessed for the number of (N_included ), mean velocity (V_mean ), and pulsatility index (PI) of the included perforators.

Statistical tests

For within-method comparisons, inter- and intrarater reliability were assessed for the manual method, and test-retest reliability was assessed for both methods from repeated 2D PC scans (without repositioning). Intraclass correlation coefficients (ICCs) and their 95% confidence intervals (CIs) were determined for N_included , V_mean , and PI for all within-method comparisons. The ICC to compare between the two methods was determined with the use of both (test-retest) scans using a multilevel nonlinear mixed model.

Results

The automated censoring method showed a moderate to good ICC (95% CI) vs. manual censoring for N_included (0.73 [0.58-0.87]) and V_mean (0.90 [0.84-0.96]), and a moderate ICC for PI (0.57 [0.37-0.76]). The test-retest reliability of the manual censoring method was considerably lower than the interrater and intrarater reliability, indicating that scanner noise dominates the uncertainty of the analysis.

Data conclusion

The proposed automated censoring method can reliably exclude small perforators affected by ghosting artifacts.

Level of evidence

Technical efficacy stage

SUBMITTER: Arts T

PROVIDER: S-EPMC7754489 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature

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Publications

Automated Assessment of Cerebral Arterial Perforator Function on 7T MRI.

Arts Tine T Siero Jeroen C W JCW Biessels Geert Jan GJ Zwanenburg Jaco J M JJM

Journal of magnetic resonance imaging : JMRI 20200818 1

<h4>Background</h4>Blood flow velocity and pulsatility of small cerebral perforating arteries can be measured using 7T quantitative 2D phase contrast (PC) MRI. However, ghosting artifacts arising from subject movement and pulsating large arteries cause false positives when applying a previously published perforator detection method.<h4>Purpose</h4>To develop a robust, automated method to exclude perforators located in ghosting artifacts.<h4>Study type</h4>Retrospective.<h4>Subjects</h4>Fifteen p ...[more]

PMID: 32810376

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Dataset Information

Automated Assessment of Cerebral Arterial Perforator Function on 7T MRI.

Background

Purpose

Study type

Subjects

Field strength/sequence

Assessment

Statistical tests

Results

Data conclusion

Level of evidence

Technical efficacy stage

Publications

Automated Assessment of Cerebral Arterial Perforator Function on 7T MRI.

Similar Datasets

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