Image stabilization and registration for tracking cells in the microvasculature

Area of Science:

• Biomedical Imaging
• Cell Biology
• Microscopy Techniques

Background:

• Intravital video microscopy is crucial for observing cellular dynamics in vivo.
• Image stabilization and registration are essential for accurate cell tracking over time and distance.
• Existing methods struggle with frame jitter and moving fields of view.

Purpose of the Study:

• To develop and validate a registration system for enhanced cell tracking in intravital microscopy.
• To address challenges posed by frame jitter and moving fields of view (FOV).
• To enable long-term, in vivo tracking of cells, such as rolling leukocytes.

Main Methods:

• A morphological approach identifies stable background regions for jitter stabilization.
• Template matching aligns subregions to a reference frame for fixed FOV stabilization.
• A modified correlation method registers consecutive fixed FOVs for moving FOV alignment.
• Active contour models are used for cell tracking.

Main Results:

• The stabilization algorithm reduced root-mean-square error (RMSE) to less than 0.5 micrometers for fixed FOV sequences.
• 15 leukocytes, previously untrackable due to jitter, were successfully tracked.
• The moving FOV registration technique achieved an RMSE of less than 0.6 micrometers.
• 11 cells were tracked over moving FOVs in 10 different venule sequences.

Conclusions:

• The proposed registration system effectively stabilizes jitter and aligns moving fields of view in intravital microscopy.
• This system enables robust in vivo cell tracking, including rolling leukocytes, over extended ranges.
• The demonstrated accuracy and capability advance the potential of intravital microscopy for biological research.