What
The detection of pathological tissue alterations by manual palpation is a simple but essential diagnostic tool used by clinicians. The "virtual palpation" of tissue has now become feasible using Magnetic Resonance Elastography (MRE). Researchers at King’s College London have developed novel MRE units that work alongside standard MRI scanners to provide high quality information on tissue characteristics following application of controlled vibrational stresses to a patient. With many disease states impacting upon biomechanics, the potential of this non-invasive method for early diagnosis, staging and follow-up of pathologies is enormous.
Why
Biopsy, an invasive medical procedure that involves taking a small sample of body tissue so it can be examined under a microscope, is still considered the gold standard for the diagnosis and follow up of tissue-related pathologies such as cancer. or fibrosis However, biopsies cause localised tissue damage, eliciting inflammatory and/or repair responses. Furthermore, if during the biopsy it is collected a too small tissue sample, it is possible to miss discrete tumours within a tissue.
On the other hand, pathologies such as cancer, fibrosis, cardiovascular diseases, and neuro-degenerative diseases all impact the tissue biomechanics. Hence, the potential of MRE is enormous, as it allows a non-invasive early diagnosis, staging, and therapy follow up via virtual palpation of the tissue.
However, previous MRE approaches have lacked efficiency, precision, reproducibility and patient-friendliness, hampering its broad clinical acceptance and adoption.
Even FDA-approved devices for performing MRE produce low resolution results due to non-uniform vibrations being generated in patients.
Benefits
The technology applied to patients with cancers and fibrosis has demonstrated impressive initial results.
Furthermore, the proposed MRE device is modular, and can be adapted to work with different organs and tissues (e.g. brain, breast, cardiac, liver, uterus, kidney).
Opportunity
The technology is protected by a US patent application, a European patent application, a Chinese patent and a Japanese patent.
A number of collaborative human clinical studies are underway involving diagnosis and staging of breast cancer, brain tumours, Alzheimer’s disease, abdominal tumours and fibrosis.
The Science
MRE quantifies in-vivo biomechanical properties of tissue by analysing the propagation of externally elicited, low magnitude, shear waves. This method requires three steps:
- sending low-frequency mechanical waves into the body via an externally applied transducer,
- imaging waves via dedicated MRI motion sensitized data acquisition sequences, and
- performing image analysis to generate false-colour images of the biomechanical properties.
The technology consists of a novel MRE unit that works alongside commercially available MRI scanners to provide high resolution information about tissue stiffness and sub-surface characteristics.
The approach provides controlled and non-distorted oscillating stress to a subject under assessment. A driver module is positioned outside the MR field for controlling the oscillating stress. Specifically, the driver module is arranged outside the MR suite and rotates a long, flexible spindle which produces vibrations via an eccentric weight in a container in direct contact with the patient (the "near-patient unit").
The driver module can be used with a number of different front transmission sections. Each front section can be designed to address the specific organ that is to be imaged (e.g. brain, breast, cardiac, liver, uterus, kidney) and it is possible, via gears in the near-patient unit, to generate more than one vibrational frequency, thereby permitting the capture of more detailed information about the tissues' stiffness and viscosity during a single scanning session.
IP Rights
The technology is protected by:
EP 3 262 434 A2 - pending European patent application;
US 15/553,933 - pending US patent application;
CN 107 438 393 B - Chinese granted patent; and
JP 6 984 959 B2 - Japanese granted patent.
Further Information
Runge, J.H. et al., (2019). "A novel magnetic resonance elastography transducer concept based on a rotational eccentric mass: preliminary experiences with the gravitational transducer". Physics in Medicine & Biology 64, 045007. doi:10.1088/1361-6560/aaf9f8
Fovargue, D. et al., (2020). "Towards noninvasive estimation of tumour pressure by utilising MR elastography and nonlinear biomechanical models: a simulation and phantom study". Scientific Reports 10. 5588. doi:10.1038/s41598-020-62367-3