Calf Muscle Perfusion in Patients With Intermittent Claudication by 3D-reconstruction of MSOT (MSOT_IC_3D)

Cross-sectional Study of Calf Muscle Perfusion Via 3D Reconstruction of Multispectral Optoacoustic Tomography in Patients With Peripheral Arterial Disease After Exercise.

The aim of the proposed study is to define independent parameters for the diagnostic assessment of the perfusion situation of the calf muscle based on 3D-reconstruction of multispectral optoacoustic tomography (MSOT) in a cross-sectional collective of patients with PAD in Fontaine stage II and a healthy control group.

This is a monocentric, prospective cross-sectional study which aims to compare the 3D-reconstructed optoacoustic signals in calf muscle after a exercise in patients with PAD in Fontaine stage II and a healthy control group in order to define MSOT thresholds. MSOT data will be correlated with CCDS, ABI, maximum walking distance in 6MWT, subjectively perceived absolute walking distance in everyday life, PAD-related life quality (VASCUQOL-6) and TASC II classification in angiographic imaging (only in case angiographic imaging is available and independent from this study).

Patients with intermittent claudication will be recruited during the consulting hours of the Department of Vascular Surgery, University Hospital Erlangen. Healthy volunteers will be acquired via posters in the clinic. Following detailed information about the study and after providing written consent, relevant clinical data will be collected from the electronical patient file, if available. In addition, a thorough anamnesis interview for relevant data and CCDS would be performed. Afterwards, the 3D-reconstructed parameters will be recorded by means of longitudinal MSOT scans before and after a heel raise exercise until the occurrence of claudication pain in the calf muscle. For patients with PAD, the more affected leg is examined. In healthy volunteers, either leg is examined. ABI would be measured before and after 6MWT. All data will be adequately pseudonymized in compliance with data protection regulations before they are used for statistical analysis. The duration of the study for participants will be max. 90 minutes. The angiographic imaging will be reviewed and analyzed (if available, independently from this study and the interval between MSOT measurement being lesser than 12 months). The complete study including the validation of the data by an independent study group is expected to be finished within one year.

Inclusion Criteria:

• Patients with PAD in Fontaine stage II or Rutherford category 1-3 or healthy volunteers
• Adults (>18 years) who are able to give their consent

Exclusion Criteria:

• Patients with PAD in Fontaine stage I, III and IV or Rutherford category 0, 4, 5 and 6 or healthy volunteers with diabetes mellitus, chronic renal failure, claudication symptoms, abnormal ABI or non-palpable foot pulses
• People with age under 18
• Absence of written consent
• Safety concerns of the study physician (person with physical, mental or psychiatric conditions which, by the judgement of the study physician, would compromise the person's safety or the quality of the data, thereby rendering the person an ineligible candidate for the study