Language
Country/Area
No result found
The amazing journey of magnetic resonance elastography: How does this technology change the rules of the medical diagnostic game?
With the advancement of medical technology, magnetic resonance elastography (MRE) has attracted widespread attention in the field of diagnosis. Since it was first developed at the Mayo Clinic in 1995, MRE has become a powerful noninvasive diagnostic tool, particularly in the staging of liver fibrosis, gradually replacing traditional biopsy and serum tests.
This technology can measure the mechanical properties of soft tissue (such as elasticity or hardness), which has become a new perspective for exploring lesions in medicine.
The principle of MRE is based on the observation that diseased tissue, such as a breast tumor, is often more rigid than surrounding normal tissue. Therefore, assessing tissue stiffness has important clinical significance. Although traditional imaging techniques such as CT, MRI and ultrasound are authoritative in imaging, they cannot provide information on the elastic modulus of soft tissues.
MRE is a three-step process: first, by applying vibrations to the surface of the patient's body, shear waves are generated to penetrate deeper into the tissue; second, MRI is used to obtain data on the propagation and speed of these waves; and finally, this information is collected by the patient's brain. The tissue stiffness can be quantitatively inferred and mapped in 3D, called an elastogram.
The Mechanics of Soft Tissue
MRE quantitatively measures the mechanical response of biological tissue to external pressure. It calculates the shear modulus of the tissue, which is a measure of the material's ability to resist elastic deformation. Biological tissues are nonlinearly elastic and have viscoelastic characteristics, and their mechanical response depends on the amplitude of the applied pressure and the deformation rate.
The relationship between shear stress and deformation of biological tissues forms a complex nature, which is one of the reasons why MRE is widely used in clinical applications.
Currently, researchers are focusing on incorporating complex viscoelastic behavior into the post-processing of the inversion algorithm, which has the potential to improve the specificity and diagnostic accuracy of MRE measurements.
Application Areas
Liver
Liver fibrosis is a common disease that may progress to cirrhosis or end-stage liver disease if not monitored. MRE-based liver stiffness measurement has been proven to be the most accurate non-invasive examination technology. This technology can provide large-area tissue stiffness measurement for the liver, thereby helping to effectively identify the degree of liver fibrosis.
Brain
The use of MRE for brain imaging began in the early 2000s, and its elastic imaging matrix has been correlated with memory tests, physical fitness tests, and the progression of various neurodegenerative diseases. Studies have shown that with aging, the viscoelastic properties of the brain decline due to the degeneration of neurons and oligodendrocytes, which enables MRE to identify potential risks of mental illness at an early stage.
Kidneys
Compared to the liver or brain, MRE examination of the kidney faces more challenges due to its complex internal structure and hidden location. Studies have shown that the stiffness of the kidneys can reflect their function and perfusion. MRE is showing more application potential in chronic kidney disease, renal tumors, etc.
Prostate
MRE can be used to detect and diagnose prostate cancer, and its hardness changes can help distinguish the difference between cancerous tissue and normal tissue. Studies have shown that when MRE is used in conjunction with the PI-RADS (version 2.1) system, its specificity reaches 95%.
Pancreas
The pancreas is considered the softest tissue in the abdominal cavity. Pancreatic diseases such as pancreatitis and pancreatic cancer can cause a significant increase in its hardness. MRE is undoubtedly an effective tool for diagnosing these lesions. The study found that the combined use of MRE-measured hardness and imaging-based tumor volume estimation can significantly improve the reliability of its clinical application.
With the continuous development of magnetic resonance elastography technology, its application will continue to expand to more fields and may even affect our overall understanding and treatment of diseases. Will current technological advances lead to revolutionary changes in medical diagnostics in the future?
