It might even be possible to diagnose fibromyalgia through an eye exam
Optical coherence tomography can measure a thin layer of nerve fibers that coat the eye, or the retinal nerve fiber layer. This can reveal a lot about fibromyalgia.
This technique is used in glaucoma and diabetic retinopathy--it is noninvasive and comfortable for the patient. Studies have shown that this can distinguish people with biologic fibromyalgia.