Background
Myalgic Encephalopathy/Chronic Fatigue Syndrome (ME/CFS) may afflict 0,4-4 percent of the population. Symptoms include extreme fatigue, post-exertional malaise and a cascade of signs defined in the “Canada-criteria”. The symptoms and signs of ME/CFS are to a large degree similar to those of cervical myelopathy and increased intracranial pressure which in other studies has been shown to correlate with widening of the optic nerve sheet diameter (ONSD). As we had noted unexpected many patients in our ME/CFS-clinic with Chiari1 or EDS we decided to make a retrospective study.
Aims
To present data on the presence of hypermobility, tonsillar ectopia or other structural narrowing in the craniocervical area and the presence of widening of the optic nerve sheet diameter in a randomized cohort of patients with ME/CFS according to the Canada criteria.
Methods
Out of a population of 286 patients diagnosed with ME/CFS we randomly selected 50 patients and assessed for hypermobility according to the Beighton score (>4). We also assessed MRIscans of the brain and cervical spine without knowledge of results from foregoing questionnaires, physical examination or other tests. Independent investigators performed the assessments following a predetermined structured protocol to measure tonsillar ectopia, structural narrowing of craniocervical segments and ONSD > 5mm.
Results
The mean age of the population was 42 years and 76 % were females. Hypermobility was present in 35 % of the population. MRI of the brain and cervical spine had been performed on 42 patients of whom 26 % had bilateral tonsillar ectopia and 88 % had narrowing of the spinal canal in the craniocervical segments. Mean ONSD was 5,3 mm SD +- 0,6, and ONSD > 5mm was present in 71% of the patients having had MRI of the brain. Conclusions: Hypermobility, tonsillar ectopia, narrowing of the space in the craniocervical segments and widening of the optic nerve sheet are common in patients with ME/CFS. These findings may impact the flow of the cerebrospinal fluid and suggests that a large portion of patients with ME/CFS may have intracranial hypertension. Further studies on the complete population are planned including measuring of the cerebrospinal fluid pressure.