Trial Outcomes & Findings for A Study Using Transorbital Alternating Current Stimulation for People With Glaucoma (NCT NCT03188042)

NCT ID: NCT03188042

Last Updated: 2024-02-09

Results Overview

Peripapillary retinal nerve fiber layer (RNFL) thickness (μm) measured using optical coherence tomography (OCT).

Recruitment status

COMPLETED

Study phase

NA

Target enrollment

18 participants

Primary outcome timeframe

Baseline, Week 4

Results posted on

2024-02-09

Participant Flow

Unit of analysis: Eyes

Participant milestones

Participant milestones
Measure
rtACS Stimulation Group
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
Overall Study
STARTED
8 16
10 20
Overall Study
COMPLETED
7 14
9 18
Overall Study
NOT COMPLETED
1 2
1 2

Reasons for withdrawal

Reasons for withdrawal
Measure
rtACS Stimulation Group
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
Overall Study
Withdrawal by Subject
1
1

Baseline Characteristics

A Study Using Transorbital Alternating Current Stimulation for People With Glaucoma

Baseline characteristics by cohort

Baseline characteristics by cohort
Measure
rtACS Stimulation Group
n=7 Participants
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=9 Participants
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
Total
n=16 Participants
Total of all reporting groups
Age, Continuous
64 years
STANDARD_DEVIATION 10 • n=5 Participants
59 years
STANDARD_DEVIATION 20 • n=7 Participants
61 years
STANDARD_DEVIATION 17 • n=5 Participants
Sex: Female, Male
Female
3 Participants
n=5 Participants
4 Participants
n=7 Participants
7 Participants
n=5 Participants
Sex: Female, Male
Male
4 Participants
n=5 Participants
5 Participants
n=7 Participants
9 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
1 Participants
n=5 Participants
0 Participants
n=7 Participants
1 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
6 Participants
n=5 Participants
9 Participants
n=7 Participants
15 Participants
n=5 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
Race (NIH/OMB)
Asian
0 Participants
n=5 Participants
2 Participants
n=7 Participants
2 Participants
n=5 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
Race (NIH/OMB)
Black or African American
2 Participants
n=5 Participants
2 Participants
n=7 Participants
4 Participants
n=5 Participants
Race (NIH/OMB)
White
4 Participants
n=5 Participants
5 Participants
n=7 Participants
9 Participants
n=5 Participants
Race (NIH/OMB)
More than one race
0 Participants
n=5 Participants
0 Participants
n=7 Participants
0 Participants
n=5 Participants
Race (NIH/OMB)
Unknown or Not Reported
1 Participants
n=5 Participants
0 Participants
n=7 Participants
1 Participants
n=5 Participants
Region of Enrollment
United States
7 participants
n=5 Participants
9 participants
n=7 Participants
16 participants
n=5 Participants

PRIMARY outcome

Timeframe: Baseline, Week 4

Peripapillary retinal nerve fiber layer (RNFL) thickness (μm) measured using optical coherence tomography (OCT).

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=14 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=18 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
Change in Peripapillary RNFL Thickness
-0.13 micrometers (μm)
Standard Deviation 2.3
-1.8 micrometers (μm)
Standard Deviation 3.91

PRIMARY outcome

Timeframe: Baseline, Week 4

Macular ganglion cell-inner plexiform layer thickness (μm) measured using OCT.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=14 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=18 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
Change in Macular Ganglion Cell-Inner Plexiform Layer Thickness
-0.13 micrometers (μm)
Standard Deviation 0.99
0.3 micrometers (μm)
Standard Deviation 4.52

PRIMARY outcome

Timeframe: Baseline, Week 4

Percentage change in optic nerve (ON) head cup-to-disc ratio measured using OCT.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=14 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=18 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
Percentage Change in ON Head Cup-to-Disc Ratio
0 percentage (%) change
Standard Deviation 0.01
0.01 percentage (%) change
Standard Deviation 0.01

PRIMARY outcome

Timeframe: Baseline, Week 4

The Humphrey Visual Field Analyzer assesses the mean deviation (dB), a measure of visual field sensitivity through threshold testing. dBs tested by the Humphrey analyzer range between 0 and 50 dB (0 is the brightest and 50 is the dimmest). A value of 0 means the patient could not see the brightest target, and a 50 means the dimmest target was seen. Most values are around 30 dB, and any numbers below this range imply a possible visual field defect.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=14 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=18 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
Change in Humphrey Visual Field Analyzer Score
0.86 dB
Standard Deviation 6.27
2.89 dB
Standard Deviation 9.65

PRIMARY outcome

Timeframe: Baseline, Week 4

The LIFE-H short form 3.1 is a 77-item questionnaire developed to measure: (1) how a respondent accomplishes regular activities and social roles and (2) respondent's satisfaction with how regular activities and social roles are accomplished. The LIFE-H total score is obtained by summing the scores on each item and then dividing by the number of items. The LIFE-H score ranges from 0 to 9, where a score of 0 indicates total handicap or total disruption in participation and a score of 9 means an optimal level of participation.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=7 Participants
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=9 Participants
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
Change in Score on Assessment of Life Habits (LIFE-H), Short Form 3.1
0.000137 score on a scale
Standard Error 0.165273
-0.089842 score on a scale
Standard Error 0.150235

PRIMARY outcome

Timeframe: Baseline, Week 4

An estimate of reading acuity is given by the smallest print size at which the patient can read the entire sentence without making significant errors. This method measures acuity to the nearest 0.1 logMAR. Each sentence in the MNRead Reading Acuity chart has 60 characters, which corresponds to 10 standard length words, assuming a standard word length of 6 characters (including a space). Reading acuity is calculated as follows: Reading acuity = size of smallest sentence read + 0.01 x number of errors.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=14 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=18 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
Change in Minnesota Low Vision Reading Test (MNRead): Reading Acuity Score
-0.02857 logMAR
Standard Deviation 0.108233
0.013333 logMAR
Standard Deviation 0.074498

PRIMARY outcome

Timeframe: Baseline, Week 4

National Eye Institute VFQ-39 measures health-related quality of life in 12 domains: general vision, ocular pain, near activities, distance activities, vision-specific social functioning, vision-specific mental health, vision-specific role difficulties, vision-specific dependency, driving, color vision, peripheral vision, and composite score. For each domain: the lowest and highest possible scores are 0 and 100 points, respectively. Higher score means higher functioning. The total score is the average of the domain scores.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=7 Participants
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=9 Participants
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
Change in Score on National Eye Institute Visual Functioning Questionnaire (VFQ-39)
3.52 score on a scale
Standard Error 2.1405453
0.95 score on a scale
Standard Error 0.089

PRIMARY outcome

Timeframe: Baseline, Week 4

The SF-36 is a 36-item patient-reported questionnaire that covers eight health domains: physical functioning (10 items), bodily pain (2 items), role limitations due to physical health problems (4 items), role limitations due to personal or emotional problems (4 items), emotional well-being (5 items), social functioning (2 items), energy/fatigue (4 items), and general health perceptions (5 items). Scores for each domain range from 0 to 100, with a higher score defining a more favorable health state. The total score is the average of the domain scores.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=7 Participants
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=9 Participants
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
Change in Score on 36-Item Short Form Survey (SF-36)
23.14 score on a scale
Standard Error 5.3030631
17.18 score on a scale
Standard Error 0.1888264

PRIMARY outcome

Timeframe: Baseline

Visual evoked potential (VEP) identifies decreased visual function and helps with discriminations of glaucomatous changes by measuring amplitude (micro volts) and latency (milliseconds (ms)) with 15% contrast parameters.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=6 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=8 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
VEP-Measured Amplitude (15% Contrast) at Baseline
5.675 micro volts
Standard Deviation 3.208632886
10.6655 micro volts
Standard Deviation 2.1296074

PRIMARY outcome

Timeframe: Baseline

Visual evoked potential (VEP) identifies decreased visual function and helps with discriminations of glaucomatous changes by measuring amplitude (micro volts) and latency (milliseconds (ms)) with 15% contrast parameters.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=6 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=8 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
VEP-Measured Latency (15% Contrast) at Baseline
119.166667 milliseconds
Standard Deviation 26.759733
130.75 milliseconds
Standard Deviation 19.70828929

PRIMARY outcome

Timeframe: Baseline

Visual evoked potential (VEP) identifies decreased visual function and helps with discriminations of glaucomatous changes by measuring amplitude (micro volts) and latency (milliseconds (ms)) with 85% contrast parameters.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=10 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=12 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
VEP-Measured Amplitude (85% Contrast) at Baseline
8.3314 micro volts
Standard Deviation 2.794988157
10.0365 micro volts
Standard Deviation 3.7914384

PRIMARY outcome

Timeframe: Baseline

Visual evoked potential (VEP) identifies decreased visual function and helps with discriminations of glaucomatous changes by measuring amplitude (micro volts) and latency (milliseconds (ms)) with 85% contrast parameters.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=10 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=12 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
VEP-Measured Latency (85% Contrast) at Baseline
110.5 milliseconds
Standard Deviation 11.051018
121 milliseconds
Standard Deviation 10.839742

PRIMARY outcome

Timeframe: Week 4

Visual evoked potential (VEP) identifies decreased visual function and helps with discriminations of glaucomatous changes by measuring amplitude (micro volts) and latency (milliseconds (ms)) with 15% contrast parameters.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=8 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=10 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
VEP-Measured Amplitude (15% Contrast) at Week 4
6.62025 micro volts
Standard Deviation 0.905566995
7.1814 micro volts
Standard Deviation 2.865013

PRIMARY outcome

Timeframe: Week 4

Visual evoked potential (VEP) identifies decreased visual function and helps with discriminations of glaucomatous changes by measuring amplitude (micro volts) and latency (milliseconds (ms)) with 15% contrast parameters.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=8 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=10 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
VEP-Measured Latency (15% Contrast) at Week 4
119.25 milliseconds
Standard Deviation 11.97566978
131.7 milliseconds
Standard Deviation 14.267971

PRIMARY outcome

Timeframe: Week 4

Visual evoked potential (VEP) identifies decreased visual function and helps with discriminations of glaucomatous changes by measuring amplitude (micro volts) and latency (milliseconds (ms)) with 85% contrast parameters.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=12 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=10 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
VEP-Measured Amplitude (85% Contrast) at Week 4
8.4108333 micro volts
Standard Deviation 4.3606635
9.8224 micro volts
Standard Deviation 2.8729446

PRIMARY outcome

Timeframe: Week 4

Visual evoked potential (VEP) identifies decreased visual function and helps with discriminations of glaucomatous changes by measuring amplitude (micro volts) and latency (milliseconds (ms)) with 85% contrast parameters.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=12 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=10 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
VEP-Measured Latency (85% Contrast) at Week 4
119.4166667 milliseconds
Standard Deviation 11.8634593
122.3 milliseconds
Standard Deviation 10.556988

PRIMARY outcome

Timeframe: Baseline

The Pelli-Robson test measures contrast sensitivity using a single large letter size (20/60 optotype), with contrast varying across groups of letters. The chart uses letters (6 per line), arranged in groups whose contrast varies from high to low. Patients read the letters, starting with the highest contrast, until they are unable to read two or three letters in a single group. A score is assigned based on the contrast of the last group in which two or three letters were correctly read. The score, a single number, is a measure of the subject's log contrast sensitivity. A Pelli-Robson score of 2.0 indicates normal contrast sensitivity of 100 percent. Scores less than 2.0 signify poorer contrast sensitivity. Pelli-Robson contrast sensitivity score of less than 1.5 is consistent with visual impairment and a score of less than 1.0 represents in visual disability.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=14 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=18 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
Pelli-Robson Contrast Sensitivity Chart Score at Baseline
1.4 LogCS
Standard Deviation 0.42
1.26 LogCS
Standard Deviation 0.47

PRIMARY outcome

Timeframe: Week 4

The Pelli-Robson test measures contrast sensitivity using a single large letter size (20/60 optotype), with contrast varying across groups of letters. The chart uses letters (6 per line), arranged in groups whose contrast varies from high to low. Patients read the letters, starting with the highest contrast, until they are unable to read two or three letters in a single group. A score is assigned based on the contrast of the last group in which two or three letters were correctly read. The score, a single number, is a measure of the subject's log contrast sensitivity. A Pelli-Robson score of 2.0 indicates normal contrast sensitivity of 100 percent. Scores less than 2.0 signify poorer contrast sensitivity. Pelli-Robson contrast sensitivity score of less than 1.5 is consistent with visual impairment and a score of less than 1.0 represents in visual disability.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=14 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=18 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
Pelli-Robson Contrast Sensitivity Chart Score at Week 4
1.39 LogCS
Standard Deviation 0.35
1.08 LogCS
Standard Deviation 0.55

PRIMARY outcome

Timeframe: Baseline

ETDRS charts have five Sloan letters on each line; the lines are of equal difficulty, and there is a geometric progression in letter size from line to line. Beginning with Chart 1, the right eye is tested with the left eye occluded. Following the completion of testing the right eye, the left eye is tested with Chart 2 while covering the right eye. Each letter is scored as right or wrong. Correct letters are circled on the scoresheet. Each letter read correctly is assigned a score and each line is totaled at the end of testing. VAS awards one point for every letter correctly guessed. The total scores range from 0 to 100, with higher scores indicating greater visual acuity.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=14 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=18 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
Early Treatment Diabetic Retinopathy Study (ETDRS) Visual Acuity Score (VAS) at Baseline
0.08 score on a scale
Standard Deviation 0.13
0.16 score on a scale
Standard Deviation 0.16

PRIMARY outcome

Timeframe: Week 4

ETDRS charts have five Sloan letters on each line; the lines are of equal difficulty, and there is a geometric progression in letter size from line to line. Beginning with Chart 1, the right eye is tested with the left eye occluded. Following the completion of testing the right eye, the left eye is tested with Chart 2 while covering the right eye. Each letter is scored as right or wrong. Correct letters are circled on the scoresheet. Each letter read correctly is assigned a score and each line is totaled at the end of testing. VAS awards one point for every letter correctly guessed. The total scores range from 0 to 100, with higher scores indicating greater visual acuity.

Outcome measures

Outcome measures
Measure
rtACS Stimulation Group
n=14 Eyes
rtACS Stimulation: Electric current stimulation; rtACS is a non-invasive application of electric current to stimulate the retina to induce synaptic efficacy, in particular those cells that have some measure of dysfunction but are not dead, and oscillations of nearby neuronal ensembles.
Sham Intervention Group
n=18 Eyes
Sham stimulation looks like rtACS, but is not active rtACS. Sham Intervention: A computer-controlled sham stimulation function for masking interventionist to study group. The device will be used to deliver a weak electric current stimulation protocol to participants via electrodes placed transorbitally, with one reference electrode positioned elsewhere.
Early Treatment Diabetic Retinopathy Study (ETDRS) Visual Acuity Score (VAS) at Week 4
0.10 score on a scale
Standard Deviation 0.14
0.16 score on a scale
Standard Deviation 0.17

Adverse Events

rtACS Stimulation Group

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Sham Intervention Group

Serious events: 0 serious events
Other events: 0 other events
Deaths: 0 deaths

Serious adverse events

Adverse event data not reported

Other adverse events

Adverse event data not reported

Additional Information

Joel Schuman, MD, FACS

NYU Langone Health

Phone: 929-455-5030

Results disclosure agreements

  • Principal investigator is a sponsor employee
  • Publication restrictions are in place