Remotely Supervised Transcranial Direct Current Stimulation: An Update on Safety and Tolerability

The overall goal of this procedure is to demonstrate a repeatable and effective methodology for administering remotely supervised transcranial direct current stimulation. This method can help answer key questions in the field of neuromodulation, such as extended dosing. The main advantage of this technique is that tDCS can be performed from a patient's home or a satellite site with real-time supervision by study personnel.

This technique enables remote administration of tDCS sessions while maintaining clinical standards away from the clinic. RS-tDCS overcomes a common limitation in neuromodulation, particularly fuse stimulation sessions studied. This method was initially piloted for treatment of cognitive impairment in multiple sclerosis, but was generalized to patients with Parkinson's Disease and would be generalizable to other conditions, as well.

Challenges surrounding this method include initial computer preparation and training of participants to ensure uniform standards. At baseline, begin by escorting the participant into the testing room. Administer relevant neuropsychological assessments based on the patient population to assess motor and cognitive abilities of the participant that will serve as screening and outcome measures.

Next, administer self-report questionnaires relevant to symptoms that are specific to the patient's disease. Finally, administer universal symptom rating inventories to allow for comparison of outcomes between patient populations. Begin by showing the participant an instructive tDCS training video that details the entire step-by-step process of administering the stimulation.

Next, prepare the head strap by having the participant attach the sponges, which are pre-moistened with 5 milliliters of saline solution, to the cable electrodes on the head strap. Ask the participant to place the head strap on their head, taking care to align the nation marker on the front of the head strap with the bridge of their nose. Then, ask the participant to pull the head strap towards the posterior end of his or her head so that the back of the head strap rests over the ineon and confirm that the participant has achieved optimal or good contact quality.

If the participant has a poor or moderate contact quality, troubleshoot by adding saline to the sponges, adjusting the head strap placement or having the participant brush hair away from the electrode sites. Next, assess the participant's aptitude to complete study procedures to determine whether he or she understands and can replicate the procedures competently at home. Finally, complete a tolerability test lasting 90 seconds to determine whether the participant is able to comfortably tolerate the target amount of direct current.

If a participant is unable to handle the target current, then reduce the amperage by 0.5 milliamperes successively until the participant is able to tolerate the stimulation. Prior to starting a stimulation session, inquire about any adverse events experienced following the previous session and administer inventory logs. Ask the participant to report the duration of sleep from the previous night, as well as any pain experienced due to the stimulation, disease specific pain, fatigue, and mood, with the aid of visual analog scales.

For the at home session, ensure the participant can connect to the internet and use remote desktop software to engage in HIPAA compliant videoconferencing. Next, have the participant prepare the head strap by attaching the pre-moistened sponges to the electrodes on the inside of the frontal head strap. Then, ask the participant to place the head strap on his or her head and monitor placement as the participant does so.

Have the participant report the contact quality, which is assessed by the device. Visually assess sponge placement and adjust sponge saturation as needed. Then, confirm that the contact quality is still optimal or moderate.

Provide the device unlock code to begin the participant's stimulation session and deliver the preset stimulation, either active or sham, for 20 minutes. Following head strap placement, have the participant verbally state the stimulation code that unlocks the device and initiates the stimulation. During the stimulation period, have the participant complete computerized cognitive training tasks that target processing speed and working memory.

After 10 minutes of stimulation, ask the participant to report any pain he or she may be experiencing due to the stimulation. After the session is complete, have the participant remove the head strap and dispose of study sponges. Finally, repeat inventory logs and ask the participant to report any pain due to the device, disease specific pain, fatigue and mood after the session, as well as any adverse events they may have experienced.

Then, plan the session for the following day. Adverse events were pooled across stimulation type and the rates of occurrence were calculated. The three most common adverse events reported were sensations of skin tingling, itching and burning.

Further, affect sizes, Cohen's d, were calculated for change in mood, fatigue and pain from baseline to study end. The active sessions in studies one and two showed moderate affect sizes for improvement. On average, participants who received active tDCS, reported heightened positive affect and reduced negative affect, fatigue and pain by study end, compared to the sham tDCS group.

Once mastered, this technique can be completed in 30 minutes or less, if performed properly. While attempting this procedure, it's important to remember to continually supervise patients throughout their session to maintain clinical standards. Following this procedure, other treatments or therapies may be paired with the stimulation to answer additional questions and to study alternative behavioral outcomes.

This technique enables research designs in the field of neuromodulation to extend dosing to patients with chronic disease courses. After watching this video, you should have a good understanding of how to perform remotely supervised tDCS sessions. Clinical standards are maintained by real-time monitoring procedures and verification of correct equipment use.

Thank you for watching and good luck with the experiments.