The LEGATOS technique: A new tissue-validated dynamic contrast-enhanced MRI method for whole-brain, high-spatial resolution parametric mapping.

Abstract

PURPOSE:

A DCE-MRI technique that can provide both high spatiotemporal resolution and whole-brain coverage for quantitative microvascular analysis is highly desirable but currently challenging to achieve. In this study, we sought to develop and validate a novel dual-temporal resolution (DTR) DCE-MRI-based methodology for deriving accurate, whole-brain high-spatial resolution microvascular parameters.

METHODS:

Dual injection DTR DCE-MRI was performed and composite high-temporal and high-spatial resolution tissue gadolinium-based-contrast agent (GBCA) concentration curves were constructed. The high-temporal but low-spatial resolution first-pass GBCA concentration curves were then reconstructed pixel-by-pixel to higher spatial resolution using a process we call LEGATOS. The accuracy of kinetic parameters (Ktrans , vp , and ve ) derived using LEGATOS was evaluated through simulations and in vivo studies in 17 patients with vestibular schwannoma (VS) and 13 patients with glioblastoma (GBM). Tissue from 15 tumors (VS) was examined with markers for microvessels (CD31) and cell density (hematoxylin and eosin [H&E]).

RESULTS:

LEGATOS derived parameter maps offered superior spatial resolution and improved parameter accuracy compared to the use of high-temporal resolution data alone, provided superior discrimination of plasma volume and vascular leakage effects compared to other high-spatial resolution approaches, and correlated with tissue markers of vascularity (P ≤ 0.003) and cell density (P ≤ 0.006).

CONCLUSION:

The LEGATOS method can be used to generate accurate, high-spatial resolution microvascular parameter estimates from DCE-MRI.

• Authors: Ka-Loh Li, Daniel Lewis, David J Coope, Federico Roncaroli, Erjon Agushi, Omar N Pathmanaban, Andrew T King, Sha Zhao, Alan Jackson, Timothy Cootes, Xiaoping Zhu
• Journal: Magnetic resonance in medicine (Magn Reson Med) Vol. 86 Issue 4 Pg. 2122-2136 (10 2021) ISSN: 1522-2594 [Electronic] United States
• PMID: 33991126 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2021 The Authors. Magnetic Resonance in Medicine published by Wiley Periodicals LLC on behalf of International Society for Magnetic Resonance in Medicine.

Chemical References

• Contrast Media

Topics

• Brain (diagnostic imaging)
• Contrast Media
• Humans
• Magnetic Resonance Imaging