Nuclear MR (NMR) spectroscopy, a new method of testing that can assess a tissue metabolic profile, offers a noninvasive technique for distinguishing between different neurological disorders in patients and may enable earlier diagnosis, according to a study published online in March in the Journal of Comparative Neurology.
While MRI can reveal loss of brain tissue, the diagnosis of many neurological degenerative disorders remains a challenge as there are no diagnostic testing methods that can distinguish between conditions such as Alzheimer's disease, Huntington's disease or Parkinson's disease consistently.
Jason B. Nikas, MD, from the department of neurosurgery at the University of Minnesota in Minneapolis, and his colleagues explained: “At the present time, no approach has been developed to systematically identify profiles of key chemical alterations that can be used as biomarkers to diagnose diseases and to monitor disease progression; or to assess mathematically the diagnostic power of potential biomarkers.”
The researchers measured the amounts of 17 different striatal concentrations of biochemical substances in the brains of 13 transgenic mice with Huntington's disease, as well as those of 17 wild mice. By way of in vivo proton NMR spectroscopy, they quanitified the amount of complex biological molecules in tissue.
The authors developed diagnostic biomarker models and clinical change assessment models and tested for them on the 30 original mice and the 31 unknown mice. Researchers compared the results to genotyping.
Nikas and colleagues found that the Huntington mutation ‘R6/2’ caused a signature change in the levels of the aforementioned substances. In addition, all models correctly diagnosed all 30 original mice and the 31 unknown mice via NMR spectroscopy.
“Scanning animals non-invasively [by NMR spectroscopy] could be useful in the monitoring of various interventions in mice with genetic disorders,” wrote the authors.
The study concluded that the technique could potentially be even more valuable for identifying human subjects who were asymptomatic, but showed the NMR spectroscopy signature of a particular disease, which could develop years later.
“Moreover, it could be very valuable in assessing disease progression and/or the efficacy of an applied medical treatment … and could potentially provide diagnostic information to distinguish different causes of dementia and other forms of neurological illness, rapidly and non-invasively,” said Nikas.