A Pilot Study to Evaluate Multi-Spectral and Laser Speckle Imaging and Multiphoton Microscopy During Vascular Occlusion

Recruiting

• Conditions: Abnormal Vascular Flow
• Interventions: Device: Multi-Spectral and Laser Speckle Imaging

• Registration Number: NCT01484730
• Lead Sponsor: University of California, Irvine

Brief Summary

The purpose of this research is to evaluate and validate the performance of non-invasive imaging modalities for assessment of skin. A pressure cuff occlusion will be used to stimulate blood flow dynamic that these instruments are designed to sense. The researcher currently plan to assess only basic feasibility of the imaging instruments.

Detailed Description

The primary reason for including pressure cuff occlusion in this protocol is to test the performance of Multi-Spectral Imaging and Laser Speckle Imaging can measure in the full range of vascular conditions ranging from ischemic (under-perfused or unsaturated) to hyperemic (over-perfused and over-saturated).

1. Modulated Imaging a non-contact optical imaging technology can detect the concentration of total hemoglobin, deoxygenated and oxygenated hemoglobin in absolute amounts in units of millimoles / unit volume of tissue measured.

2. Laser Speckle Imaging a non-contact optical imaging technology consists of a coherent light source, camera, and image acquisition system. This image device can measure and compare relative flow in vasculature at varied time points.

Study Timeline

• Study Start: 2011-11
• Study First Submitted: 2011-11-29
• Study First Submitted QC: 2011-12-01
• Study First Posted: 2011-12-02
• Status Verified: 2025-01
• Last Update Submitted: 2025-03-25
• Last Update Posted: 2025-03-30
• Primary Completion: 2026-08
• Study Completion: 2026-08

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 150

Inclusion Criteria

• Male and female adult 18 years and older

Exclusion Criteria

• Younger than 18 years of age
• Pregnant women

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Vascular Occlusion	Multi-Spectral and Laser Speckle Imaging	Multi-Spectral and Laser Speckle Imaging

Primary Outcome Measures

Name	Time	Method
Skin blood flow	4 weeks	The key factor of interest is measuring the changes in the fluorescence signal of the epidermal cells during the arm occlusion, which will provide information about changes in cellular metabolism during cellular oxygen deprivation. Time series of optical sections (two-dimensional x-y images parallel to the skin surface of about 250x250 µm2) at the same depth will be obtained before, during and after the arm occlusion. The images will be based on two-photon excitation of endogenous fluorophores (NADH). To quantify the fluorescence signal, which will provide information about changes of cellular metabolism, we will use the integrated brightness of each image (same rectangular area for all images) as a measure of the signal. The integrated brightness is defined as the sum of pixels weighted over the brightness values (or gray values) of the pixel. A statistical plan is not appropriate at this stage of the pilot study.

Trial Locations

Locations (1)

Beckman Laser Institute and Medical Clinic; 🇺🇸 Irvine, California, United States