Non-enhanced MR imaging of cerebral aneurysms: 7 Tesla versus 1.5 Tesla

Karsten H Wrede; Philipp Dammann; Christoph Mönninghoff; Sören Johst; Stefan Maderwald; I Erol Sandalcioglu; Oliver Müller; Neriman Özkan; Mark E Ladd; Michael Forsting; Marc U Schlamann; Ulrich Sure; Lale Umutlu

doi:10.1371/journal.pone.0084562

Non-enhanced MR imaging of cerebral aneurysms: 7 Tesla versus 1.5 Tesla

PLoS One. 2014 Jan 6;9(1):e84562. doi: 10.1371/journal.pone.0084562. eCollection 2014.

Affiliations

¹ Erwin L. Hahn Institute for Magnetic Resonance Imaging, University Duisburg-Essen, Essen, Germany ; Department of Neurosurgery, University Hospital Essen, Essen, Germany.
² Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany.
³ Erwin L. Hahn Institute for Magnetic Resonance Imaging, University Duisburg-Essen, Essen, Germany ; Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Essen, Germany.
⁴ Department of Neurosurgery, University Hospital Essen, Essen, Germany.

Abstract

Purpose: To prospectively evaluate 7 Tesla time-of-flight (TOF) magnetic resonance angiography (MRA) in comparison to 1.5 Tesla TOF MRA and 7 Tesla non-contrast enhanced magnetization-prepared rapid acquisition gradient-echo (MPRAGE) for delineation of unruptured intracranial aneurysms (UIA).

Material and methods: Sixteen neurosurgical patients (male n = 5, female n = 11) with single or multiple UIA were enrolled in this trial. All patients were accordingly examined at 7 Tesla and 1.5 Tesla MRI utilizing dedicated head coils. The following sequences were obtained: 7 Tesla TOF MRA, 1.5 Tesla TOF MRA and 7 Tesla non-contrast enhanced MPRAGE. Image analysis was performed by two radiologists with regard to delineation of aneurysm features (dome, neck, parent vessel), presence of artifacts, vessel-tissue-contrast and overall image quality. Interobserver accordance and intermethod comparisons were calculated by kappa coefficient and Lin's concordance correlation coefficient.

Results: A total of 20 intracranial aneurysms were detected in 16 patients, with two patients showing multiple aneurysms (n = 2, n = 4). Out of 20 intracranial aneurysms, 14 aneurysms were located in the anterior circulation and 6 aneurysms in the posterior circulation. 7 Tesla MPRAGE imaging was superior over 1.5 and 7 Tesla TOF MRA in the assessment of all considered aneurysm and image quality features (e.g. image quality: mean MPRAGE7T: 5.0; mean TOF7T: 4.3; mean TOF1.5T: 4.3). Ratings for 7 Tesla TOF MRA were equal or higher over 1.5 Tesla TOF MRA for all assessed features except for artifact delineation (mean TOF7T: 4.3; mean TOF1.5T 4.4). Interobserver accordance was good to excellent for most ratings.

Conclusion: 7 Tesla MPRAGE imaging demonstrated its superiority in the detection and assessment of UIA as well as overall imaging features, offering excellent interobserver accordance and highest scores for all ratings. Hence, it may bear the potential to serve as a high-quality diagnostic tool for pretherapeutic assessment and follow-up of untreated UIA.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Aged
Artifacts
Female
Humans
Intracranial Aneurysm / diagnosis*
Intracranial Aneurysm / pathology
Magnetic Resonance Angiography* / methods
Magnetic Resonance Angiography* / standards
Male
Middle Aged
Prospective Studies

Grants and funding

An IFORES grant to KHW from the University Duisburg-Essen supported the research [http://www.uni-due.de/med/forschung/forschungsfoerderung/ifores.shtml]. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.