Influence of Fitzpatrick Skin Phototype and Body Mass Index on Non-invasive Optoacoustic Imaging
NCT Number: NCT06541496
Status: RECRUITING
Study Type: OBSERVATIONAL
Conditions: Healthy
Interventions: DEVICE: Multispectral Optoacoustic Tomography (MSOT)
Sponsor: University of Erlangen-Nürnberg Medical School
Sex: ALL
Age: ADULT, OLDER_ADULT
Enrollment: 130
Study Design: Observational Model: |Time Perspective: p
Start Date: 2024-06-14
Completion Date: 2025-12-31
Locations: iThera Medical Headquarters, Munich, Bavaria, 81379, Germany

Summary:
Multispectral Optoacoustic Tomography (MSOT) is a promising imaging technology that utilizes pulsed laser light. While melanin content in the skin has been reported to influence light-based measurements in pulse oximetry and near-infrared spectroscopy, its effects on MSOT are not well understood. This proposed study aims to investigate how different Fitzpatrick skin phenotypes (FSP) and body mass index (BMI) influence muscle perfusion and oxygenation during arterial occlusion and muscle exercise over time. Healthy volunteers with varying skin tones (as defined by FSP) and BMI will be recruited and subjected to leg arterial occlusion and toe raise exercises. They will then be scanned on different body areas (arms and legs) to assess changes in muscle perfusion and oxygenation using MSOT.

Primary Outcome Measures: Quantitative hemoglobin-associated signal (in arbitrary units), Hemoglobin signal in the measured muscle regions in all different cohorts, immediately before and after intervention (occlusion and exercise)
Secondary Outcome Measures: Muscle oxygenation (in arbitrary units), Oxygenated hemoglobin signal in the measured muscle regions in all different cohorts, immediately before and after intervention (occlusion and exercise)|Oxygen saturation (in %), Proportion of oxygenated hemoglobin signal compared with total hemoglobin signal in the measured muscle regions in all different cohorts, immediately before and after intervention (occlusion and exercise)|Heart rate (in bpm), heart rate of the healthy volunteers, immediately before and after intervention (occlusion and exercise)|Blood pressure (in mm Hg), blood pressure of the healthy volunteers, immediately before and after intervention (occlusion and exercise)|Weight (in kg), measured by body scale, baseline|Age in years, Participant questionnaire., baseline|Gender: male, female, other, Participant questionnaire., baseline|Skin tone based on Fitzpatrick questionnaire self-assessment (type 1-6, 1 being the palest, 6 being the darkest), Participant questionnaire., baseline|Dominant side, Participant questionnaire., baseline|Sport frequency, Participant questionnaire., baseline|Information on last physical exercise and caffeine and alcohol consumption, Participant questionnaire., baseline|Quantitative collagen, lipid, water and melanin signal (in arbitrary units), Signal in the measured muscle regions and the skin (melanin) in all different cohorts, immediately before and after intervention (occlusion and exercise)|Skin tone based on Fitzpatrick scale self-assessment (type 1-6, 1 being the palest, 6 being the darkest), color card as reference, baseline|Skin tone based on Fitzpatrick scale examiner-assessment (type 1-6, 1 being the palest, 6 being the darkest), color card as reference, baseline