Label-free photoacoustic microscopy of peripheral nerves
Peripheral neuropathy is a common neurological problem that affects millions of people worldwide. Diagnosis and treatment of this condition are often hindered by the difficulties in making objective, noninvasive measurements of nerve fibers. Photoacoustic microscopy (PAM) has the ability to obtain high resolution, specific images of peripheral nerves without exogenous contrast. We demonstrated the first proof-of-concept imaging of peripheral nerves using PAM. As validated by both standard histology and photoacoustic spectroscopy, the origin of photoacoustic signals is myelin, the primary source of lipids in the nerves. An extracted sciatic nerve sandwiched between two layers of chicken tissue was imaged by PAM to mimic the in vivo case. Ordered fibrous structures inside the nerve, caused by the bundles of myelin-coated axons, could be observed clearly. With further technical improvements, PAM can potentially be applied to monitor and diagnose peripheral neuropathies.
Additional Information© 2014 SPIE. Paper 130677R received Sep. 17, 2013; revised manuscript received Dec. 4, 2013; accepted for publication Dec. 5, 2013; published online Jan. 6, 2014. This work was sponsored in part by the National Institutes of Health Grant Nos. DP1 EB016986 (NIH Director's Pioneer Award), R01 CA134539, and R01 CA159959. Lihong Wang has a financial interest in Microphotoacoustics, Inc. and Endra, Inc., which, however, did not support this work. Konstantin Maslov has a financial interest in Microphotoacoustics, Inc., which, however, did not support this work.
Published - JBO_19_1_016004.pdf