tFUS for Blind Spot

Overseen By Mark S George, MD

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: Medical University of South Carolina

Must not be taking: Psychoactive drugs

Disqualifiers: Depression, Anxiety, Schizophrenia, Bipolar, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 1

Duration: 1 session

30 Participants Needed

Trial Summary

Will I have to stop taking my current medications?

The trial does not specify if you need to stop taking your current medications, but you cannot participate if you are using any non-prescribed psychoactive medications or drugs.

What data supports the effectiveness of the treatment tFUS for Blind Spot?

Research shows that transcranial focused ultrasound (tFUS) can non-invasively reach deep brain areas and modulate brain activity, which suggests it might help with conditions involving brain function. While specific data on its effectiveness for treating blind spots isn't available, its ability to target specific brain regions with high precision is promising for various neurological applications. ^{1 2 3 4 5}

How is the tFUS treatment for Blind Spot different from other treatments?

Transcranial focused ultrasound (tFUS) is unique because it is a non-invasive treatment that can target deep brain structures with high precision, unlike other treatments that may not reach these areas as effectively. It uses sound waves to modulate brain activity, offering a novel approach compared to traditional methods that might involve surgery or less precise stimulation techniques. ^{1 2 3 4 6}

What is the purpose of this trial?

The purposes of this research study is to: 1. Develop a technique of transcranial Focused Ultrasound Stimulation (tFUS) where meaningful effects on the brain can be easily measured. 2. Use this technique to measure threshold for effective tFUS in individuals. 3. Determine whether disruption of conscious visual detection, versus non-conscious visually-guided behavior have different thresholds for disruption with tFUS.

Eligibility Criteria

This trial is for healthy individuals who can safely undergo a procedure that temporarily affects their vision. Specific criteria for joining or reasons to be excluded aren't provided, but typically participants must meet certain health standards and not have conditions that could interfere with the study.

Inclusion Criteria

I am either male or female.

My vision and hearing are normal, or corrected to normal.

I do not have any neurological or psychological illnesses.

Exclusion Criteria

I have been diagnosed with depression or an anxiety disorder.

I have been diagnosed with schizophrenia or bipolar disorder.

Pregnancy (or suspected/possible pregnancy or plan to become pregnant in the short term)

Timeline

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants receive transcranial Focused Ultrasound Stimulation (tFUS) to measure the threshold for effective tFUS and produce a transient scotoma

1 session

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness after treatment

10 minutes

Treatment Details

Interventions

• tFUS

Trial Overview The study is testing a technique using the Brainsonix Bx Pulsar machine to apply focused ultrasound (tFUS) to the brain. It aims to find out how much tFUS is needed to affect visual perception without causing harm.

Participant Groups

Group I: tFUS over V1 Experimental Treatment 1 Intervention

All subjects will get tFUS, open label

Who Is Running the Clinical Trial?

Medical University of South Carolina

Lead Sponsor

Trials

994

Recruited

7,408,000+

Findings from Research

Transcranial focused ultrasound (tFUS) can selectively target and modulate deep brain structures, such as the amygdala and entorhinal cortex, in healthy adults, leading to significant changes in brain perfusion and activity.

The study demonstrated that tFUS does not activate the auditory cortex, indicating that its effects are due to direct neuromodulation rather than an acoustic response, suggesting potential therapeutic applications for neurological and psychiatric disorders.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Transcranial focused ultrasound selectively increases perfusion and modulates functional connectivity of deep brain regions in humans. Kuhn, T., Spivak, NM., Dang, BH., et al.[2023]

A systematic review of 33 studies on low-intensity transcranial focused ultrasound stimulation (TFUS) indicates that adverse effects are very rare, with most studies showing no significant negative outcomes even when safety limits were exceeded.

However, at high stimulation intensities, TFUS can potentially cause serious issues like hemorrhage, cell death, and unintended blood-brain barrier opening, highlighting the need for further research to establish clear safety guidelines.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Safety of transcranial focused ultrasound stimulation: A systematic review of the state of knowledge from both human and animal studies. Pasquinelli, C., Hanson, LG., Siebner, HR., et al.[2020]

Transcranial focused ultrasound (tFUS) is a promising non-surgical technique for neuromodulation that offers better spatial resolution compared to traditional electro and electromagnetic methods.

tFUS can effectively target sub-cortical brain structures non-invasively, and its combination with BOLD functional MRI allows for enhanced examination of brain activity in humans.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Transcranial focused ultrasound for BOLD fMRI signal modulation in humans. Leo Ai, ., Mueller, JK., Grant, A., et al.[2022]

Transcranial focus ultrasound stimulation (tFUS) can significantly modulate excitability in the human motor cortex, with different parameters leading to either increased or decreased excitability, as shown in a study involving 10 subjects.

The study revealed that tFUS affects neurotransmitter levels, decreasing GABA and increasing glutamate concentrations, which suggests it alters the balance of excitatory and inhibitory signals in the brain, potentially impacting motor function and plasticity.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Excitatory-inhibitory modulation of transcranial focus ultrasound stimulation on human motor cortex. Zhang, T., Guo, B., Zuo, Z., et al.[2023]

Transcranial focused ultrasound (FUS) can effectively stimulate the motor area of the brain in rats using lower acoustic intensities (4.9-5.6 W/cm²) with specific pulsing parameters, indicating its potential for safe brain stimulation.

The study found that pulsed sonication is more effective than continuous sonication for eliciting motor responses, suggesting that this method could be optimized for therapeutic applications while adhering to safety limits for biological tissue.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Focused ultrasound-mediated non-invasive brain stimulation: examination of sonication parameters. Kim, H., Chiu, A., Lee, SD., et al.[2022]

Transcranial focused ultrasound (tFUS) can reversibly suppress neuronal activity in the thalamus, as demonstrated by its effects on somatosensory evoked potentials (SSEP) in a rodent model, indicating its potential as a non-invasive neuromodulation technique.

The primary mechanism of this suppression appears to be thermal effects caused by the focused ultrasound, as the suppression correlated with temperature changes without causing any pathological damage to the tissue.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Reversible neuroinhibition by focused ultrasound is mediated by a thermal mechanism. Darrow, DP., O'Brien, P., Richner, TJ., et al.[2020]

References

1. Switzerland pubmed.ncbi.nlm.nih.gov

Transcranial focused ultrasound selectively increases perfusion and modulates functional connectivity of deep brain regions in humans. [2023]

2. United States pubmed.ncbi.nlm.nih.gov

Safety of transcranial focused ultrasound stimulation: A systematic review of the state of knowledge from both human and animal studies. [2020]

3. United States pubmed.ncbi.nlm.nih.gov

Transcranial focused ultrasound for BOLD fMRI signal modulation in humans. [2022]

4. England pubmed.ncbi.nlm.nih.gov

Excitatory-inhibitory modulation of transcranial focus ultrasound stimulation on human motor cortex. [2023]

5. United States pubmed.ncbi.nlm.nih.gov

Focused ultrasound-mediated non-invasive brain stimulation: examination of sonication parameters. [2022]

6. United States pubmed.ncbi.nlm.nih.gov

Reversible neuroinhibition by focused ultrasound is mediated by a thermal mechanism. [2020]