Liver diagnosis breakthrough
with Mayo Clinic MRI development
MR Elastography provides early warning
Rochester, MN, September 7:
Mayo Clinic
researchers have developed a new technique for using magnetic
resonance imaging (MRI) to accurately measure the hardness or
elasticity of the liver. First tests show this technology -- called
MR Elastography (MRE) -- holds great promise for detecting liver
fibrosis, a common condition that can lead to incurable cirrhosis if
not treated in time. Traditionally, liver fibrosis is usually
diagnosed using needle biopsies, which can involve complications and
may be inaccurate due to sampling errors. The new technology
promises to provide an accurate, painless, and lower risk
alternative to liver biopsy and may have implications for diagnosing
cancer. These research findings appeared in the journal Radiology.
"This is potentially an important
diagnostic advance, since conventional imaging techniques, such as
CT, MRI and ultrasound are not capable of identifying liver fibrosis
prior to the onset of cirrhosis," says Richard Ehman, M.D., Mayo
researcher and lead investigator on the study.
"The Elastogram"
The healthy liver is very soft
compared to most other tissues and especially compared to a liver
with cirrhosis, which is rock hard. The development by Dr. Ehman and
his colleagues applies vibrations to the liver and then utilizes a
modified form of MRI to obtain pictures of the mechanical waves
passing through the organ. The imaging can be accomplished in as
little as 20 seconds. The wave pictures are then processed to
generate a quantitative image of tissue stiffness -- called an
elastogram.
Researchers compared results of the
process on 12 patients with biopsy-proven liver fibrosis with those
of 12 healthy participants. This pilot trial of MRE showed
strikingly elevated stiffness in patients with fibrosis and that the
stiffness increased with the progression of the condition.
Impact of the Research
The availability of a reliable,
non-invasive method for detecting liver fibrosis could lead to early
diagnosis -- in patients considered at risk for liver disease -- and
increase their chances for successful treatment. For example, 170
million people worldwide are infected with chronic hepatitis C and a
significant number will develop cirrhosis, which is untreatable.
Even if some risk factors are identified, there is no way to predict
which patients will develop fibrosis, and successive liver biopsies
in all these patients aren't possible. Non-invasive monitoring with
MRE of those at risk would detect the problem early and help assess
the effect of treatments.
Collaboration and Support
Others on the research team include
Meng Yin; Olivier Rouviere, M.D.; Jayant Talwalkar, M.D.; M. Alex
Dresner, Ph.D.; Phillip Rossman; Lawrence Burgart, M.D.; and Jeff
Fidler, M.D. The research was funded in part by the National
Institutes of Health.