Repetitive transorbitale Wechselstromstimulation bei akuter autoimmunvermittelter Sehnerventzündung: Eine Pilotstudie zu vorläufiger Wirksamkeit und Sicherheit - ACSON

Device: active-rtACS treatment;Device: sham-rtACS treatment

Inclusion Criteria:

Participants fulfilling all of the following inclusion criteria are eligible for the study:

- Informed Consent as documented by signature

- Participants are capable of giving informed consent

- Participant who have a good knowledge of German (patient information and consent must
be understood)

- Patients, presenting with typical signs and symptoms suggestive of a first-ever
episode of unilateral acute autoimmune, inflammatory, demyelinating ON, including
idiopathic ON and ON suggestive of multiple sclerosis (MS) (typical clinically
isolated syndrome, or with an established diagnosis of relapsing-remitting MS
according to latest panel criteria and no better explanation)

- Patients with high-contrast visual acuity of = 0.63 (decimal system) corresponding to
a LogMAR value of = 0.2 on the affected eye (assessed using a Snellen chart during
clinical routine)

- Patients presenting in clinics within 14 days of symptom onset

- In principle 18-50 year old female and male patients may be recruited. However, since
the randomization of patients will be controlled for gender and participants will be
enrolled one at a time on a continuous basis, the gender might become relevant late in
the study (e.g. if the female block has already been fully recruited and only males
might still be enrolled).

- Patients are receiving standard-of-care treatment for ON (cortisone therapy)

Exclusion Criteria:

The presence of any one of the following exclusion criteria will lead to exclusion of the
participant:

- Patient without legal capacity who is unable to understand the nature, significance
and consequences of the trial

- Women who are pregnant or have the intention to become pregnant during the course of
the study (For women who can get pregnant, pregnancy will be omitted using a pregnancy
test when checking for inclusion and exclusion criteria. Patients will be informed
that they must use contraception during the study)

- Patients with a previous clinical history of ON in the respective eye

- Patients with obvious retinal pathology other than that associated with ON

- Patients who are unable to perform the study assessments (e.g. OCT examination)
because of a severe nystagmus (repetitive, uncontrolled eye movements causing unsteady
fixation)

- Patients with a recent eye surgery

- Patients with known anti-aquaporin-4- or myelin oligodendrocyte glycoprotein- antibody
seropositivity

- Patients with contraindications to the class of device under study (for rtACS):
implanted electronic devices, metallic artefacts in the head (excluding dentition),
epilepsy, brain cancer, pregnancy, breastfeeding, increased intraocular pressure
without appropriate treatment, arterial hypertension without appropriate treatment,
skin irritations at intended positions of electrodes, cognitive deficits (unable to
provide written informed consent or follow the instructions)

- Known or suspected non-compliance, drug or alcohol abuse

- Inability to follow the procedures of the study, e.g. due to language problems,
psychological disorders, dementia, etc. of the participant

- Participation in another study with investigational drug/device within the 30 days
preceding and during the present study

- Previous enrolment into the current study

- Enrolment of the investigator, his/her family members, employees and other dependent
persons