Vagal Nerve Stimulation for Dilated Pupil

Overseen By Justin Cottrell

Age: 18+

Sex: Any

Trial Phase: Academic

Sponsor: NYU Langone Health

Disqualifiers: Heart abnormalities, Dysautonomias, Lung diseases, others

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

Compensation: Varies

Number of Visits: 1

Duration: 1 day

30 Participants Needed

Trial Summary

What is the purpose of this trial?

This trial is testing if stimulating a nerve in the ear with electricity during ear surgery can make the pupils get bigger.

Do I need to stop my current medications for the trial?

The trial information does not specify whether you need to stop taking your current medications. It's best to discuss this with the research team or your doctor.

What data supports the effectiveness of the treatment Arnold's Nerve Stimulation for dilated pupil?

Research suggests that vagal nerve stimulation, like Arnold's Nerve Stimulation, can influence pupil size by affecting brain chemicals involved in pupil dilation. Some studies show that this type of stimulation can increase pupil size, indicating its potential effectiveness for treating dilated pupils. ^{1 2 3 4 5}

Is vagal nerve stimulation generally safe for humans?

Vagal nerve stimulation (VNS) is generally considered safe, but it can have side effects like voice changes, cough, headache, and pain. Serious issues like infection can occur with surgically implanted devices, but newer non-invasive methods are safer and more tolerable. ^{1 5 6 7 8}

How does vagal nerve stimulation differ from other treatments for dilated pupils?

Vagal nerve stimulation (VNS) is unique because it uses electrical impulses to stimulate the vagus nerve, which can lead to pupil dilation by affecting brain activity and neuromodulation. Unlike other treatments that might directly target the eye or use medications, VNS works by influencing the nervous system, potentially offering a novel approach for conditions involving pupil size. ^{1 2 3 4 9}

Research Team

J. Thomas Roland Jr.

Principal Investigator

NYU Langone Health

Eligibility Criteria

This trial is for adults over 18 years old who are undergoing cochlear implantation or vagal nerve stimulator implantation and are willing to participate. It's not for those with a history of ear surgery, congenital malformations, pregnant/breastfeeding individuals, or anyone with certain medical conditions like heart arrhythmias, lung diseases, ulcers, dysautonomias, vasovagal syncope, or pre-existing hoarseness.

Inclusion Criteria

I am over 18 and getting a vagal nerve stimulator implant.

I am scheduled for cochlear implant surgery.

I am scheduled for a vagal nerve stimulator implantation.

Exclusion Criteria

You will be excluded if you have a history of fainting due to a medical condition.

Patients undergoing vagal nerve stimulator implantation: pregnant or breastfeeding

I do not have lung diseases like asthma causing shortness of breath.

Timeline

Screening

Participants are screened for eligibility to participate in the trial

1-2 weeks

Treatment

Participants receive electrical stimulation of Arnold's Nerve during cochlear implantation surgery to measure pupil dilation

1 day

1 visit (in-person)

Follow-up

Participants are monitored for safety and effectiveness after the procedure

2-4 weeks

Treatment Details

Interventions

• Arnold's Nerve Stimulation

Trial Overview The study tests how the pupil dilates when Arnold's Nerve (part of the vagus nerve) is stimulated with an electrical device during routine cochlear implant surgery. The aim is to understand the connection between this stimulation and changes in pupil size.

Participant Groups

Group I: Vagal Nerve Stimulation during Cochlear Implantation Surgery Experimental Treatment 1 Intervention

Participants undergoing cochlear implantation will receive electrical stimulation during the procedure to stimulate the Arnold's nerve to measure pupil dilation.

Group II: Vagal Nerve Stimulator Implantation Active Control 1 Intervention

Control cohort undergoing vagal nerve stimulator implantation.

Who Is Running the Clinical Trial?

NYU Langone Health

Lead Sponsor

Trials

1,431

Recruited

838,000+

Findings from Research

Transcutaneous auricular vagus nerve stimulation (taVNS) can induce significant pupil dilation in healthy subjects, particularly at a stimulation intensity of 2 mA under scotopic lighting conditions.

The study highlights that the effects of taVNS are influenced by specific stimulation parameters and the experimental setup, indicating the need for careful consideration in future research.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effects of transcutaneous auricular vagal nerve stimulation on pupil size. Capone, F., Motolese, F., Di Zazzo, A., et al.[2021]

The study involving 49 participants demonstrated that transcutaneous auricular vagus nerve stimulation (taVNS) can enhance pupil dilation, which is a biomarker for noradrenergic activity, indicating a potential mechanism of action for taVNS.

Higher stimulation settings of taVNS resulted in a linear increase in pupil dilation, supporting the idea that taVNS may activate noradrenergic pathways, although it also caused more intense and unpleasant sensations compared to sham stimulation.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Short bursts of transcutaneous auricular vagus nerve stimulation enhance evoked pupil dilation as a function of stimulation parameters. D'Agostini, M., Burger, AM., Franssen, M., et al.[2023]

In a study involving 33 healthy young volunteers, transcutaneous auricular vagus nerve stimulation (taVNS) did not significantly affect pupil size or pupil responses, which were hypothesized to be potential biomarkers for the effectiveness of taVNS.

Despite the expectation that taVNS would enhance pupil responses due to its mechanism of action linked to locus coeruleus activation, the results suggest that pupil measures may not be reliable predictors of individual responses to taVNS in clinical settings.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

No modulation of pupil size and event-related pupil response by transcutaneous auricular vagus nerve stimulation (taVNS). Keute, M., Demirezen, M., Graf, A., et al.[2021]

Vagus nerve stimulation (VNS) is effective for treating refractory epilepsy and depression, but traditional methods involve surgical implantation, which carries risks such as infection and bradycardia.

New non-invasive VNS systems eliminate the need for surgery, improving safety and tolerability, and allowing patients to administer stimulation on demand, potentially expanding its use in various medical conditions.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Surgically implanted and non-invasive vagus nerve stimulation: a review of efficacy, safety and tolerability. Ben-Menachem, E., Revesz, D., Simon, BJ., et al.[2022]

In a study of 24 children undergoing intermittent vagal nerve stimulation over a total of 61 patient years, 15 adverse events were reported, with 13 likely related to the device, indicating a need for careful monitoring during treatment.

Despite the occurrence of adverse events, vagal nerve stimulation was generally well tolerated, and unlike standard drug therapies, these events did not typically require stopping the treatment, although they sometimes led to unexpected surgeries.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Adverse events in children receiving intermittent left vagal nerve stimulation. Murphy, JV., Hornig, GW., Schallert, GS., et al.[2019]

References

1. Netherlands pubmed.ncbi.nlm.nih.gov

The effects of transcutaneous auricular vagal nerve stimulation on pupil size. [2021]

2. Italy pubmed.ncbi.nlm.nih.gov

Short bursts of transcutaneous auricular vagus nerve stimulation enhance evoked pupil dilation as a function of stimulation parameters. [2023]

3. Netherlands pubmed.ncbi.nlm.nih.gov

Pupil dilatation in response to vagal afferent electrical stimulation is mediated by inhibition of parasympathetic outflow in the rat. [2007]

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

Graded recruitment of pupil-linked neuromodulation by parametric stimulation of the vagus nerve. [2023]

5. England pubmed.ncbi.nlm.nih.gov

No modulation of pupil size and event-related pupil response by transcutaneous auricular vagus nerve stimulation (taVNS). [2021]

6. England pubmed.ncbi.nlm.nih.gov

Surgically implanted and non-invasive vagus nerve stimulation: a review of efficacy, safety and tolerability. [2022]

7. Scotland pubmed.ncbi.nlm.nih.gov

Vagus nerve stimulator-related speech/exercise induced cough. [2018]

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

Adverse events in children receiving intermittent left vagal nerve stimulation. [2019]

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

Characterization of vagus nerve stimulation-induced pupillary responses in epileptic patients. [2023]