Welcome to the new version of CaltechAUTHORS. Login is currently restricted to library staff. If you notice any issues, please email coda@library.caltech.edu
Published June 2012 | Published
Journal Article Open

Label-free photoacoustic microscopy of myocardial sheet architecture


Cardiac myofibers are organized into sheet architectures, which contribute to up to 40% of the heart wall thickening for ejection of blood for circulation. It is important to delineate the sheet architecture for a better understanding of cardiac mechanisms. However, current sheet imaging technologies are limited by fixation-induced dehydration/deformation and low spatial resolution. Here we implemented high-resolution label-free photoacoustic microscopy (PAM) of the myocardial sheet architecture. With high endogenous optical-absorption contrast originating mainly from cytochrome, myoglobin, and melanin, PAM can image the unfixed, unstained and unsliced heart without introducing deformation artifacts. A fresh blood-free mouse heart was imaged by PAM ex vivo. The three-dimensional branching sheets were clearly identified within 150 µm depth. Various morphological parameters were derived from the PAM image. The sheet thickness (80±10  μm) and the cleavage height (11±1  μm) were derived from an undehydrated heart for the first time. Therefore, PAM has the potential for the functional imaging of sheet architecture in ex vivo perfused and viable hearts.

Additional Information

© 2012 SPIE. Paper 12186L received Mar. 18, 2012; revised manuscript received May 3, 2012; accepted for publication May 8, 2012; published online Jun. 6, 2012. The authors thank Dr. Igor Efimov for providing the dog heart sections and Dr. Da-Kang Yao for experimental assistance. This work was sponsored in part by National Institutes of Health (NIH) grants R01 EB000712, R01 EB008085, R01 CA134539, U54 CA136398, R01 CA157277, and R01 CA159959. L.W. has a financial interest in Microphotoacoustics, Inc. and Endra, Inc., which, however, did not support this work.

Attached Files

Published - JBO_17_6_060506.pdf


Files (1.4 MB)
Name Size Download all
1.4 MB Preview Download

Additional details

August 22, 2023
October 20, 2023