Transmission Laser Speckle Contrast Imaging Combined With Optical Clearing Using Magnetic Resonance Contrast Agents

Area of Science:

• Biomedical Optics
• Medical Imaging
• Diabetes Research

Background:

• Noninvasive optical diagnostic methods are crucial for assessing diabetes-related vascular and tissue changes.
• Laser speckle contrast imaging (LSCI) and optical coherence tomography (OCT) are promising contactless visualization techniques.
• Developing new criteria for diabetes assessment is a significant unmet need.

Purpose of the Study:

• To investigate the use of magnetic resonance (MR) contrast agents with LSCI and OCT.
• To evaluate the differentiation of healthy versus diabetic rat ear tissues.
• To assess dynamic and structural changes induced by MR agents in diabetic models.

Main Methods:

• Alloxan-induced type 1 diabetes model in rats.
• Application of MR contrast agents (Gadovist, Magnevist) in conjunction with LSCI and OCT.
• Evaluation of scattering coefficient (µs) kinetics during optical clearing.
• Analysis of blood flow rate in rat ear vessels.

Main Results:

• MR contrast agents effectively reduced the scattering coefficient in rat ear tissues.
• Gadovist showed a greater reduction in µs (18.6% healthy, 16.1% diabetic) compared to Magnevist (12.6% healthy, 6.8% diabetic).
• Diabetic rats exhibited reduced blood flow indicators in ear vessels compared to healthy controls.

Conclusions:

• MR contrast agents are effective optical clearing agents for OCT and LSCI.
• This study pioneered the investigation of MR agents in multimodal optical imaging for diabetes.
• The findings support the multimodal application of speckle imaging for enhanced optical clearing assessment.