LPR Fluorescence Pilot

Healthy Volunteers Inclusion Criteria: * Participant is Aged 18 or above * Participant has capacity to understand written English * Participant is not on regular prescription medicines * Participant has an RSI score of 0 * Participant has a body mass index (BMI) of 18.5 - 34.9 kg/m2 (bounds included) Exclusion Criteria: * Participant has experienced any symptoms of LPR or GORD symptoms in the past year * Participant has taken any medication for GORD/LPR in the past year (e.g. proton pump inhibitors, h2 antagonists, over the counter antacids) * Participant has active oral disease * Participant has a significant medical diagnosis Patients with symptoms of LPR Inclusion Criteria: * Participant is Aged 18 or above * Participant has capacity to understand written English * Participant has an RSI score of \>13 * Participant has a body mass index (BMI) of 18.5 - 34.9 kg/m2 (bounds included * Participant has been referred for 24hr ambulatory pH-impedance monitoring Exclusion Criteria: * Participant has active oral disease * Participant has other ongoing health problems that could account for their LPR symptoms. * Participant has NOT undergone nasoendoscopy within last 6 months OR does not have one scheduled within next 6 weeks * Previous antireflux surgery (e.g. fundoplication or magnetic sphincter augmentation) * Previous bariatric surgery (e.g. gastric bypass or sleeve gastrectomy)