Learning objectives
Discuss the different techniques and parameters used in Perfusion MR Imaging.
Recognizethe applications of Perfusion MR Imaging in brain tumors.
Describe its utility in the differentiation of gliomas from other brain tumors,
as well as tumor grading.
Describe its role in treatment response assessment.
Background
Conventional contrast-enhanced MR of the brain,
given the anatomical information it provides,
is the study of choice to characterize brain tumors and to evaluate post-treatment changes; nevertheless,
it sometimes gives limited information to establish a specific diagnosis and to differentiate between post-treatment changes and recurrence.
Perfusion MR imaging is an advanced imaging technique that provides information about tumor behavior such as histological grading of gliomas,
differentiation of brain tumors,
and treatment response assessment.
Findings and procedure details
1.
Perfusion MR Imaging
Perfusion is a biological function that refers to the delivery of oxygen and nutrients to tissue by means of blood flow.
Perfusion MR Imaging is a technique that evaluates the cerebral microvasculature through changes in signal due to a tracer passing through blood vessels.
1.1Perfusion Techniques
There are two major approaches to measure cerebral perfusion with MRI: those with and without the use of an exogenous contrast agent (Figure 1).
The first group of techniques includes application of an exogenous,
intravascular,...
Conclusion
MR perfusion is a reliable,
noninvasive tool that provides physiologic information not available with conventional MR imaging.
It helps in the characterization of brain tumors and in the evaluation of therapeutic outcomes.
It has a role in the differentiation of pseudoprogression,
radiation necrosis and tumor recurrence.
MR perfusion techniques should be part of the brain tumor MRI protocols and in the post-treatment follow-up imaging in order to provide the most accurate diagnosis,
since it will have a direct impact on the patient management.
Personal information
Dr.
Azalea Garza Báez
Neuroradiology resident.
Department of Radiology,
Hospital Universitario "Dr.
José Eleuterio González",
Monterrey,
Nuevo León,
México.
Email:
[email protected]
References
1.
Guzmán-de-Villoria J,
Fernández-García P,
Mateos-Pérez J,
Desco M.
Estudio de la perfusión cerebral mediante técnicas de susceptibilidad magnética: técnica y aplicaciones.
Radiología.
2012;54(3):208-220.
2.
Essig M,
Shiroishi M,
Nguyen T,
Saake M,
Provenzale J,
Enterline D et al.
Perfusion MRI: The Five Most Frequently Asked Technical Questions.
American Journal of Roentgenology.
2013;200(1):24-34.
3.
Covarrubias DJ,
Rosen BR,
Lev MH.
Dynamic magnetic resonance perfusion imaging of brain tumors.
Oncologist.
2004;9:528-37.
4.
Sanghvi D.
Post-treatment imaging of high-grade gliomas.
Indian Journal of Radiology and Imaging.
2015;25(2):102....