A study protocol for evaluating the efficacy and safety of skin electrical stimulation for Leber hereditary optic neuropathy: a single-arm, open-label, non-randomized prospective exploratory study

Figures & data

Figure 1 Trial flow diagram.

Figure 2 Inclusion and exclusion criteria for the study.

Table 1 Schedule for the study

	Screening	Skin electrical stimulation						Follow-up
		0W	2W	4W	6W	8W	10W	11W	14W	18W
Visit number	1	2	3	4	5	6	7	8	9	10
Deviation window (days)	−28	0	±1	±1	±1	±1	±7	±7	±7	±14
Informed consent	●
Medical history	●
BCVA	●	●	●	●	●	●	●	●	●	●
Slit-lamp biomicroscopy	●	●	●	●	●	●	●	●	●	●
Intraocular pressure	●	●	●	●	●	●	●	●	●	●
Fundus examination	●	●	●	●	●	●	●	●	●	●
CFF	●	●	●	●	●	●	●	●	●	●
Specular microscope	●		●			●				●
Color test	●									●
HVF	●		●			●		●	●	●
MP-3	●					●				●
OCT	●		●			●				●
Multifocal VEP	●									●
Observation of subjective and objective findings (face photo etc)	●	●	●	●	●	●	●
Adverse effect review		●	●	●	●	●	●	●	●	●

Note: BCVA will be converted to logMAR. Color tests will be performed using standard pseudoisochromatic plates part 2 for acquired color vision defects (SPP-2). The Humphrey static visual field analyzer will be performed with a central 30–2 SITA program with stimulus size V. MP-3 will be performed with the macula 12S2 program. We have adopted the 3D-OCT^® as the instrument of OCT to evaluate the thickness of circumpapillary retinal nerve fiber layer (cpRNFL) and ganglion cell complex (GCC) in the macula. To record the dermal symptoms where electrode pads are placed, a photograph of the face will be taken after each SES treatment. Also to help determine effectiveness, BCVA, CFF, HVF, multifocal VEP, and MP-3 tests will be performed. To explore the safety of the SES approach, numerous tests will be utilized, employing slit-lamp biomicroscopy, fundus examination, OCT, and a specular microscopy adverse review will also be performed.

Abbreviations: BCVA, best corrected visual acuity; CFF, critical fusion frequency; HVF, Humphrey visual field; LogMAR, logarithm of minimum angle resolution; MP-3, microperimetry-3; OCT, optical coherence tomography; VEP, visual evoked potential.