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Imaging
Functional Information on Meningiomas Through
Perfusion Magnetic Resonance Imaging
Hao Zhang,
1,2
Guixiang Zhang
2
and Matthijs Oudkerk
1
1. Department of Radiology, Shanghai Jiaotong University Affiliated First Hospital; 2. Department of Radiology, University Medical Center Groningen
Abstract
This article focuses on the use of perfusion magnetic resonance imaging (MRI), and in particular dynamic susceptibility contrast-enhanced
MRI (DSC-MRI), to assess haemodynamics in meningiomas. We first introduce the basic principles of DSC-MRI and the most popular imaging
techniques and perfusion parameters for data analysis of DSC-MRI. We then review the blood supply characteristics of meningiomas and
how perfusion MRI is applied in meningiomas to help the subtyping of different meningiomas and to differentiate between benign
and malignant meningiomas. Our first-hand experiences are also included. We conclude that DSC perfusion MRI can provide critical
information on the vascularity of meningiomas that is not available with conventional MRI. DSC perfusion MRI measurements are helpful
in the pre-operative subtyping and grading of meningiomas.
Keywords
Perfusion, magnetic resonance imaging (MRI), meningioma, brain, tumours, diagnosis
Disclosure: The authors have no conflicts of interest to declare.
Received: 22 January 2009 Accepted: 27 July 2009
Correspondence: Hao Zhang, Department of Radiology, Shanghai Jiaotong University Affiliated First Hospital, 100# Haining Road, Shanghai, 20080, China. E: chlzhcx@163.com
Perfusion is defined as the steady-state delivery of nutrients and nervous system (CNS), the recent application of MRI to visualise tissue
oxygen via blood to tissue per unit volume or mass and is typically physiology or function has met with great success. Indeed, a whole
measured in millilitres per 100g of tissue per minute.
1
Because blood new field known as functional MRI has arisen to apply these
flow brings crucial nutrients, and because it is disturbed in many techniques. Because blood flow is altered in many pathophysiological
disease processes, monitoring of this key physiological parameter states, from abnormal cognition through stroke to brain tumours, use
can often provide insight into disease. of MRI to study blood flow is one of the most clinically relevant of the
many forms of functional MRI. Dynamic susceptibility contrast, arterial
The brain is an unusual organ in the haemodynamic sense, with a spin labelling (ASL) and methods to measure permeability are the
high metabolic rate that is sustained through high cerebral blood three techniques that have been used to quantify the perfusion of
flow (CBF). CBF is defined as the volume of blood moving through a brain in many research and clinical applications. Rather than
given brain region per unit time. Normal CBF is typically greater than surveying the entire field of brain perfusion imaging, this article
50–60ml/100g/min. Unlike other high-flow organs, the limited space focuses on the use of perfusion MRI and, in particular, dynamic
inside the bony cranium requires an efficient regulation system, susceptibility contrast-enhanced MR imaging (DSC-MRI) to assess
which is accomplished with a high capillary density but remarkably haemodynamics in meningiomas.
low cerebral blood volume (CBV). CBV is defined as the total volume
of blood in a given region of the brain. CBV has units of millilitres of Basic Theory and Data Analysis of
blood per 100g of brain tissue (ml/100g); normal CBV is 2–5ml/100g. Dynamic Susceptibility Contrast-enhanced
Mean transit time (MTT) is a slightly more complex concept. Because Magnetic Resonance Imaging
the transit time of blood through the brain parenchyma varies DSC-MRI, first described in 1991 by Rosen et al.,
4
uses rapid
depending on the distance travelled between arterial inflow and measurements of MRI signal change after the injection of a bolus of a
venous outflow, the MTT is defined as the average of the transit time paramagnetic MRI contrast agent.
5
This is the most commonly
of blood through a given brain region, integrated across these employed perfusion MRI technique and has been studied extensively
different paths. Mathematically, MTT is related to both CBV and CBF in clinical settings.
according to the central volume principle, which states that
MTT = CBV/CBF.
2,3
Conceptually, MTT can be thought of as the time Gadolinium chelates with high magnetic susceptibility were used as
required for blood to cross from the arterial to the venous side of contrast agents in DSC-MRI. Given their size and low lipophilicity, they
the circulation. MTT is typically measured in seconds. are constrained to the intravascular space by a normal blood–brain
barrier (BBB). These agents can be used as ‘tracers’ by injecting them
While magnetic resonance imaging (MRI) has traditionally been used as tight intravenous (IV) boluses and then imaging their initial
to evaluate anatomy, with its main application being the central passage through the brain vasculature. This requires larger-gauge
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