A 3-year Multi-center Study to Describe Changes of OCT Parameters Under Treatment With Gilenya®

Inclusion Criteria Patients eligible for inclusion in this study have to fulfill all of the following criteria: 1. Written informed consent must be obtained before any assessment is performed. 2. Male or female subjects aged 18-65 years. 3. Subjects with relapsing remitting MS defined by 2010 revised McDonald criteria (see Appendix 4). 4. Patients with Expanded Disability Status Scale (EDSS) score of 0-6.0 inclusive (see Appendix 6). 5. Patients stable on immunomodulatory treatment with fingolimod for at least 1 month and at most 4 months prior to screening according to local label 6. Neurologically stable with no evidence of relapse within 30 days prior to inclusion date 7. Sufficient ability to read, write, communicate and understand Exclusion Criteria Patients fulfilling any of the following criteria are not eligible for inclusion in this study: 1. Patients who have been treated with: * systemic corticosteroids or immunoglobulins within 1 month prior to screening; * immunosuppressive medications such as azathioprine, cyclophosphamide, or methotrexate within 3 months prior to screening; * monoclonal antibodies (including natalizumab) within 3 months prior to screening; * mitoxantrone within 6 months prior to screening * cladribine at any time. 2. Patients with any medically unstable condition, as assessed by the primary treating physician at each site. 3. Patients with any of the following cardiovascular conditions : * history of myocardial infarction or with current unstable ischemic heart disease; * Heart failure (NYHA III-IV) or any severe cardiac disease as determined by the Investigator (see Appendix 5); * history or presence of a second-degree AV block, Type II or a third-degree AV block * patients receiving Class Ia (ajmaline, disopyramide, procainamide, quinidine) or III antiarrhythmic drugs (e.g., amiodarone, bretylium, sotalol, ibulitide, azimilide, dofelitide); * proven history of sick sinus syndrome; * uncontrolled hypertension 4. Patients with severe respiratory disease, pulmonary fibrosis, or chronic obstructive pulmonary disease (Class III-IV). 5. Patients with history of specific MRI findings (tumor, subdural haematoma, post-contusional changes, territorial stroke, neurodegenerative disorders, aneurysm/arteriovenous malformation, evidence of past macroscopic haemorrhage, or other relevant MRI findings that would interfere with evaluation) 6. Any severe disability or clinical impairment that can prevent the patient to meet all study requirements at the investigator's discretion 7. History of malignancy of any organ system, treated or untreated, within the past 5 years whether or not there is evidence of local recurrence or metastases, with the exception of localized basal cell carcinoma of the skin 8. Patients who have received an investigational drug (excluding fingolimod) or therapy within 90 days or 5 half-lives of screening, whichever is longer. 9. Pregnant or nursing (lactating) women, where pregnancy is defined as the state of a female after conception and until the termination of gestation, confirmed by a positive hCG test (serum) 10. Patients with any ophthalmologic reason for RNFL pathology other than MS, such as: optic neuropathy, active advanced glaucoma, injury of the optic nerve based on the ophthalmologist's clinical judgment 11. history or presence of severe myopia 1. in patients who have not had refractive surgery, a refractive error of greater than 6.00 diopters 2. pathologic fundus changes of high myopia, such as retinal pigmentary atrophy, besides peripapillary atrophy (atrophy involving the macula) or a staphyloma 3. in patients that have had previous refractive surgery, an axial eye length of greater than 26 mm 12. Acute optic neuritis within the past 6 months before screening 13. Evidence of advanced, non-proliferative or proliferative diabetic retinopathy 14. Presence of retinal conditions associated with edema, subretinal fluid, cysts, etc. 15. Concomitant use of drugs that may directly affect retinal structure and function (e.g. chronic systemic corticosteroids \[\>30 consecutive days; doses higher than Cushing threshold e.g. prednisone 7.5mg/d\], intraocular anti-angiogenic drugs \[ranibizumab, bevacizumab\], intraocular steroids etc.)