Dataset Information

A comparison of simultaneous multislice and conventional diffusion tensor imaging techniques for ischemic stroke evaluation at 1.5T.

ABSTRACT:

Objective

Diffusion tensor imaging (DTI) is a promising technique for ischemic stroke evaluation; however, acquisition time is longer than DWI. Simultaneous multislice (SMS) imaging acquires multiple slices together and reduces scan time. This study compared conventional and SMS DTI for ischemic stroke workup.

Methods

Following IRB approval, the departmental stroke protocol was supplemented with SMS DTI on a clinical 1.5T MRI. Cases suspicious for ischemic stroke outside the treatment window were included. Standard DTI (STD-DTI, 20-direction, b = 2000 s/mm²), was followed by SMS-2-DTI (two slices simultaneously imaged). Two blinded neuroradiologists independently assessed image quality and DTI-trace status (positive/negative = stroke/other). Average image quality, interrater reliability (κ), receiver operating characteristic area under the curve (AUC), signal-to-noise ratio (SNR = DTI-source min/max/average), coefficient of variation (CV), mean diffusivity (MD), and fractional anisotropy (FA, of DTI-trace) were compared using two-tailed t-tests and a p < .05.

Results

41 patients were evaluated. SMS-2-DTI decreased DTI time by 132.17 ± 15.33 s, a 45% reduction. SMS-2-DTI reduced image quality (STD-DTI 4.7 ± 0.5 vs SMS-2-DTI 3.8 ± 0.6, p < .001). Diagnostic accuracy persisted, AUC was high for observer 1 (STD-DTI 0.95, 95%CI = 0.88-1.00 vs SMS-2-DTI 0.94, 95%CI = 0.87-1.00, p = .86) and observer 2 (STD-DTI 0.89, 95%CI = 0.79-0.99 vs SMS-2-DTI 0.86, 95%CI = 0.76-0.97, p = .66). Interrater reliability was high for STD-DTI (κ = 0.80, 95%CI = 0.61-0.98) and SMS-2-DTI (κ = 0.84, 95%CI = 0.67-1.00). SMS-2-DTI significantly decreased average SNR (STD-DTI 42.85 ± 4.44 vs SMS-2-DTI 32.58 ± 4.30, p < .001), and CV MD (STD-DTI 0.23 ± 0.03 vs 0.20 ± 0.04, p < .001). CV FA and CV DTI-trace were not statistically different.

Conclusions

This study supports using SMS to accelerate DTI for ischemic stroke workup at 1.5T in the non-hyper-acute setting.

Advances in knowledge

This study highlights the feasibility of accelerated multislice DTI for faster diagnostic DTI-trace images capable of ischemic stroke detection.

SUBMITTER: Culleton S

PROVIDER: S-EPMC10997011 | biostudies-literature | 2023 Jan

REPOSITORIES: biostudies-literature

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Publications

A comparison of simultaneous multislice and conventional diffusion tensor imaging techniques for ischemic stroke evaluation at 1.5T.

Culleton Sinéad S Hashemizadeh Kolowori Seyyed Kazem SK Roberts John J de Havenon Adam A DiBella Edward E McNally J Scott JS

The British journal of radiology 20221205 1141

<h4>Objective</h4>Diffusion tensor imaging (DTI) is a promising technique for ischemic stroke evaluation; however, acquisition time is longer than DWI. Simultaneous multislice (SMS) imaging acquires multiple slices together and reduces scan time. This study compared conventional and SMS DTI for ischemic stroke workup.<h4>Methods</h4>Following IRB approval, the departmental stroke protocol was supplemented with SMS DTI on a clinical 1.5T MRI. Cases suspicious for ischemic stroke outside the treat ...[more]

PMID: 36469531

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Dataset Information

A comparison of simultaneous multislice and conventional diffusion tensor imaging techniques for ischemic stroke evaluation at 1.5T.

Objective

Methods

Results

Conclusions

Advances in knowledge

Publications

A comparison of simultaneous multislice and conventional diffusion tensor imaging techniques for ischemic stroke evaluation at 1.5T.

Similar Datasets

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