Electrical Impedance Tomography & Selective Stimulation of Vagus Nerve
Trial Parameters
Brief Summary
Electroceuticals is a new field in which the goal is to treat a wide variety of medical diseases with electrical stimulation of autonomic nerves. A prime target for intervention is the cervical vagus nerve as it is easily surgically accessible and supplies many organs in the neck, thorax and abdomen. It would be desirable to stimulate selectively in order to avoid the off-target effects that currently occur. This has not been tried in the past, both because of limitations in available technology but also because, surprisingly, the fascicular organisation of the cervical vagus nerve is almost completely unknown. The aim of this research is to investigate the functional anatomy of fascicles in the cervical vagus nerve of humans. This will include defining innervation to the heart, lungs and recurrent laryngeal and, if possible, the oesophagus, stomach, pancreas, liver and gastrointestinal tract. It will be achieved by defining fascicle somatotopic functional anatomy with spatially-selective vagus nerve stimulation (sVNS) and the new method of fast neural imaging with Electrical Impedance Tomography (EIT). EIT is a novel imaging method in which reconstructed tomographic images of resistance changes related to the opening of ion channels over milliseconds can be produced using rings or arrays of external electrodes. In humans, using a nonpenetrating nerve cuff with sVNS or fast neural EIT, this will be performed for 30 minutes transiently during an operation to insert a vagal nerve stimulator for treatment of epilepsy and deliver images in response to activity such as respiration or the electrocardiogram (ECG).
Eligibility Criteria
Inclusion Criteria: * Age over 18 * Written informed consent by patient or proxy * Clinical diagnosis of disorder affected directly or indirectly or will possibly respond to vagus nerve stimulation Exclusion Criteria: * Aged 17 and below * Unfortunately, it is unlikely that interpreters of all languages will be available in the unit so persons who cannot understand verbal explanation in English and for whom we could not find a suitable consultee would have to be excluded from the study.