I love that more and more studies are coming out backing up the idea that Fibromyalgia is a nerve disorder (or neurological issue) . A couple of studies now have shown that about 50% of those diagnosed with Fibromyalgia also have small fiber polyneuropathy. I had the test done a while back and it came back borderline (enough so that my Neurologist says I have it).
This latest study goes a little further and while it’s small it supports the idea that Fibromyalgia is a nerve disorder. This 2015 study by Ramirez et al looked at the nerves in the eyes of Fibromyalgia patients. Why? Because they eye – specifically the cornea – has the highest density of nerve fibers in the body (which equates to the most sensitivity). No wonder it hurts so much when we get an eyelash stuck on our eye.
A new imaging method allows doctors to non-invasively look at the nerve structure of the eye. It works with a software set that estimates the total number of nerves in a small area (square millimeter). This study first looked at the nerve structures in the cornea, and then correlated the nerve density to responses from standard questionnaires regarding patient pain levels, sleep quality, anxiety, depression, fatigue, and neuropathic pain. This was a very small study (only 17 Fibro patients and 17 healthy people). A single ophthalmologist examined the images of all participants. This is important because it ensures accurate comparisons. This ophthalmologist did not know which eyes belonged to the Fibro group or the healthy patients.
The ophthalmologist looked at stromal nerves, examining average corneal nerve thickness, smoothness, and corneal sub-basal plexus nerve density. The Fibromyalgia patients evaluated in this study showed severe symptoms based on the questionnaires. When comparing the nerve thickness, Fibromyalgia patients have significantly thinner corneal stroma nerves than the healthy individuals. Nerve smoothness values were also significantly lower. Fibromyalgia patients also displayed decreased sub-basal plexus small nerve fiber density. While Fibromyalgia patients showed significant differences from healthy controls, there was no correlation between symptom severity among the Fibromyalgia patients and their specific nerve results.
While the study is small it does indicate that Fibromyalgia patients have both smoother and thinner corneal nerves than healthy individuals, and that the small fiber neuropathy seen in other areas of the body is present in the eyes as well. I think perhaps if this study is expanded we may see a much simpler way to confirm small fiber neuropathy as it relates to Fibromyalgia.
The current test requires cutting small holes in the skin. While the holes they cut in me have “healed” they are still visible and red, and often itch (it’s been about 6 months since I had that test). I see my ophthalmologist annually for the many eye problems that I suffer related to Fibromyalgia and I can’t help but wonder if this might not shed some light on those issues.
Hopefully these researchers or others will expand on this study so that it can reach a point that can be considered useful in diagnosis and further research of Fibromyalgia. Right now it does seem to shed a little more light on the focus of Fibromyalgia as a nerve disorder.