Natural course of CCSVI criteria in 7 MS patients with ≥2 criteria over a median time period of 12 weeks.

At baseline and at follow-up, for stenosis measurements, method 1 and 2 were used.Method 1 IJVs stenosis as a local CSA reduction of ≥50% across the IJV. Method 2 IJVs stenosis as a ≤0.3 cm2 CSA, measured at the level of the thyroid gland.ΔCSA = CSAsupine – CSAupright.Due to lack of assessment, in patient 2, patient 4 and patient 6 criterion V was not assessed at follow-up.NP not present; this CCSVI criterion was not present.Abbreviations.CCSVI, chronic cerebrospinal venous insufficiency; CSA, cross section area; IJV, internal jugular vein; L, left; MS, multiple sclerosis; NP, not present; R, right; VV, vertebral vein.