Pupillary Dilation During Post-Auricular Vagal Nerve Stimulation

Study Overview
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Brief Summary
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The research team will evaluate pupillary dilation from vagal nerve stimulation of Arnold's Nerve, a branch of the vagus nerve, during routine cochlear implantation surgery.

Detailed Description
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The objective of this study is to determine if electrical stimulation of Arnold's Nerve, a branch of the vagus nerve, can result in vagal nerve response through the measurement of pupillary dilation

Official Title
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Single-Center Study of Pupillary Dilation During Post-Auricular Vagal Nerve Stimulation

Conditions
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Hearing Loss

Intervention / Treatment
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* Device: Electrical stimulator


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing cochlear implantation: will be undergoing surgery for a cochlear implant is over the age of 18 is willing to participate in the study Patients undergoing vagal nerve stimulator implantation: will be undergoing implantable vagal nerve stimulation is over the age of 18 is willing to participate in the study Exclusion Criteria: Patients undergoing cochlear implantation: is under the age of 18 has history of prior ear surgery, congenital ear malformation, or cochlear implantation pregnant or breastfeeding patients cannot undergo the standard-of-care implantation procedures required for participation in the study. medical comorbidities resulting in exclusion are guided by the AANS exclusion criteria for VNS and include the following: One vagus nerve Receiving other concurrent forms of brain stimulation Heart arrhythmias or other heart abnormalities Dysautonomias (abnormal functioning of the autonomic nervous system) Lung diseases or disorders (shortness of breath, asthma, etc.) Ulcers (gastric, duodenal, etc.) Vasovagal syncope (fainting) Pre-existing hoarseness Patients undergoing vagal nerve stimulator implantation: is under the age of 18 has history of prior ear surgery, congenital ear malformation, or cochlear implantation pregnant or breastfeeding medical comorbidities resulting in exclusion are guided by the AANS exclusion criteria for VNS and include the following: One vagus nerve Receiving other concurrent forms of brain stimulation Heart arrhythmias or other heart abnormalities Dysautonomias (abnormal functioning of the autonomic nervous system) Lung diseases or disorders (shortness of breath, asthma, etc.) Ulcers (gastric, duodenal, etc.) Vasovagal syncope (fainting) Pre-existing hoarseness

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Non-Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Vagal Nerve Stimulation during Cochlear Implantation Surgery<br>Participants undergoing cochlear implantation will receive electrical stimulation during the procedure to stimulate the Arnold's nerve to measure pupil dilation. | Device: Electrical stimulator<br>* Electrical stimulation will be used to stimulate the Arnold's nerve and measure pupil dilation. The electrical stimulator is part of the standard facial nerve monitoring unit that we utilize in cochlear implantation and will be setup prior to surgery in standard fashion. The device allows for constant current stimulation, with stimulus range between 0-30 mA.<br>|
| No Intervention: Vagal Nerve Stimulator Implantation<br>Control cohort undergoing vagal nerve stimulator implantation. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pupillary Dilation during Procedure | Pupillary dilation (mm) measured via non-invasive pupillary measurement camera. | Day 1 (During procedure - typically 1 hour in duration) |