More accurate testing for nerve damage

At last they seem to be finding new ways of accurately assessing nerve damage. The EMG's etc are fine for giving a general idea but can't see the damage to the myelin sheath (a biopsy always needed - not good for a living patient) and can therefore be misleading. Luckily, most doctors give the EMG result equal status with the patient's symptoms and story but some patients are still sent away after being told there's apparently nothing wrong, when the numbness, tingling and pain tell them that there quite clearly is. The research in today's post, as highlighted by Sciencedaily.com (see link below) seems a much more promising development in the search for a detailed medical assessment, although it's important to realise that at this stage, it's just research and probably a long way off normal practice.

New Imaging Technique Evaluates Nerve Damage







ScienceDaily (Sep. 14, 2011) — A new imaging technique could help doctors and researchers more accurately assess the extent of nerve damage and healing in a live patient.

Researchers at Laval University in Québec and Harvard Medical School in Boston aimed lasers at rats' damaged sciatic nerves to create images of the individual neurons' insulating sheath called myelin. Physical trauma, repetitive stress, bacterial infections, genetic mutations, and neurodegenerative disorders such as multiple sclerosis can all cause neurons to lose myelin. The loss slows or halts the nerve's transmission of electrical impulses and can result in symptoms such as numbness, pain, or poor muscle control.

Using their images of neurons, the researchers measured the thickness of the myelin at different locations and times after the rats' sciatic nerve was damaged. Two weeks after injury the nerve's myelin covering had thinned considerably, but at four weeks the nerve had begun to heal.

Traditionally, researchers could only obtain such myelin measurements by removing the nerve and slicing it into thin layers, a technique whose destructive nature prevented it from being used to evaluate nerve injuries in living patients. The new imaging method, described in the September issue of the Optical Society's (OSA) open-access journal Biomedical Optics Express, holds promise as a diagnostic tool for doctors treating nerve damage or degenerative diseases, the researchers write.

Story Source: The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Optical Society of America, via EurekAlert!, a service of AAAS.

http://www.sciencedaily.com/releases/2011/09/110913103211.htm