# Evaluation of the clinical utility of maximum intensity projections of 3D contrast-enhanced, T1-weighted imaging for the detection of brain metastases

Hainc, Nicolin; Federau, Christian; Tyndall, Anthony; Mittermeier, Andreas; Bink, Andrea; Stippich, Christoph; Schubert, Tilman (2020). Evaluation of the clinical utility of maximum intensity projections of 3D contrast-enhanced, T1-weighted imaging for the detection of brain metastases. Cancer Reports, 3(5):e1277.

## Abstract

BACKGROUND

To visualize and assess brain metastases on magnetic resonance imaging, radiologists face an ever-increasing pressure to perform faster and more efficiently. The usage of maximum intensity projections (MIPs) of contrast-enhanced T1-weighed (T1ce) magnetization-prepared rapid acquisition with gradient echo (MP-RAGE) images proposes to increase reading efficiency by increasing lesion conspicuity while reducing in the number of images to be reviewed.

AIM

To assess if MIPs save reading time and achieve the same level of diagnostic accuracy as standard 1 mm T1ce images for the detection of brain metastases.

METHODS

Forty-four patients were included in this retrospective study. Axial reformations of T1ce MP-RAGE (TR/TE = 2300/2.25 ms, resolution = 1 mm$^{3}$ ) images were analyzed and post-processed into 5 and 10 mm MIPs. Two readers evaluated the randomly assorted images and recorded reading time. Reading time differences were analyzed using the Wilcoxon test, and inter-reader statistics were performed using Bland-Altman plots.

RESULTS

About 22.5 61.2 s/study and 43.8 ± 159.9 s/study were saved using 5 and 10 mm MIPs, respectively. Combined average sensitivity was 92.0% for 5 mm MIPs and 86.3% for 10 mm MIPs compared to standard 1 mm axial slices, with an average rate of 0.98 and 0.57 false positives per study, respectively CONCLUSION: While 5 mm and 10 mm T1ce MP-RAGE MIPs showed a clinical benefit in reducing reading times for evaluation of brain metastases, they should be used in conjunction with standard 1 mm images for best sensitivity and specificity, a practice which possibly annuls their benefit.

## Abstract

BACKGROUND

To visualize and assess brain metastases on magnetic resonance imaging, radiologists face an ever-increasing pressure to perform faster and more efficiently. The usage of maximum intensity projections (MIPs) of contrast-enhanced T1-weighed (T1ce) magnetization-prepared rapid acquisition with gradient echo (MP-RAGE) images proposes to increase reading efficiency by increasing lesion conspicuity while reducing in the number of images to be reviewed.

AIM

To assess if MIPs save reading time and achieve the same level of diagnostic accuracy as standard 1 mm T1ce images for the detection of brain metastases.

METHODS

Forty-four patients were included in this retrospective study. Axial reformations of T1ce MP-RAGE (TR/TE = 2300/2.25 ms, resolution = 1 mm$^{3}$ ) images were analyzed and post-processed into 5 and 10 mm MIPs. Two readers evaluated the randomly assorted images and recorded reading time. Reading time differences were analyzed using the Wilcoxon test, and inter-reader statistics were performed using Bland-Altman plots.

RESULTS

About 22.5 61.2 s/study and 43.8 ± 159.9 s/study were saved using 5 and 10 mm MIPs, respectively. Combined average sensitivity was 92.0% for 5 mm MIPs and 86.3% for 10 mm MIPs compared to standard 1 mm axial slices, with an average rate of 0.98 and 0.57 false positives per study, respectively CONCLUSION: While 5 mm and 10 mm T1ce MP-RAGE MIPs showed a clinical benefit in reducing reading times for evaluation of brain metastases, they should be used in conjunction with standard 1 mm images for best sensitivity and specificity, a practice which possibly annuls their benefit.

## Statistics

### Citations

Dimensions.ai Metrics

### Altmetrics

Detailed statistics

Item Type: Journal Article, refereed, original work 04 Faculty of Medicine > University Hospital Zurich > Clinic for Neuroradiology 610 Medicine & health Health Sciences > Oncology Life Sciences > Cancer Research English 1 October 2020 04 Sep 2020 14:56 27 Jan 2022 02:28 Wiley-Blackwell Publishing, Inc. 2573-8348 This is the peer reviewed version of the following article: Hainc, N, Federau, C, Tyndall, A, et al. Evaluation of the clinical utility of maximum intensity projections of 3D contrast‐enhanced, T1‐weighted imaging for the detection of brain metastases. Cancer Reports. 2020;e1277., which has been published in final form at https://doi.org/10.1002/cnr2.1277. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving. Green PubMed ID. An embargo period may apply. https://doi.org/10.1002/cnr2.1277 32770649

Preview
Content: Accepted Version
Filetype: PDF
Size: 339kB
View at publisher