How micro is microdissection? Laser removal of stratum corneum of skin to expose the epidermal battery

Steven L. Jacques; Felix Ejike Ejeckam; Frank K. Tittel

doi:10.1117/12.147667

7 July 1993 How micro is microdissection? Laser removal of stratum corneum of skin to expose the epidermal battery

Steven L. Jacques, Felix Ejike Ejeckam, Frank K. Tittel

Proceedings Volume 1882, Laser-Tissue Interaction IV; (1993) https://doi.org/10.1117/12.147667
Event: OE/LASE'93: Optics, Electro-Optics, and Laser Applications in Scienceand Engineering, 1993, Los Angeles, CA, United States

Abstract

How micro is laser microdissection? This study compared the spatial resolution of laser microdissection achieved by two laser systems: the ArF excimer laser which is strongly absorbed by tissue protein, and the Er:YAG laser which is strongly absorbed by tissue water. Both lasers penetrate tissue only a couple microns and are suitable for laser microdissection, and in this report the lasers ablated the outer dead-cell layer of the skin called the stratum corneum. The study involved dorsal skin sites on 8 rats for the ArF excimer and 10 rats for the Er:YAG. Ag/AgCl-gel electrodes were used to measure the passive DC resistance (R) and the active DC voltage (V) of skin sites which had received increasing numbers of ablative laser pulses (9 mJ/pulse, Er:YAG; 48 mJ/pulse, ArF excimer). About 8 pulses were required before a sudden drop in Ra and a sudden rise in V was observed. The R dropped from 4 +/- 0.2 (18) Mohm down to 1.5 +/- 0.2 (18) Mohm; mean +/- standard deviation (number of skin sites). The V was initially -56 +/- 5 mV, then dropped to -3 +/- 0.4 mV after laser ablation penetrated and destroyed the battery. The Er:YAG laser required 8.3 +/- 1.5 pulses to achieve 50% of the full change in R and V; the ArF excimer laser required 76 +/- 2 pulses. The changes in R and V per depth of tissue ablated were identical for the two lasers, despite their distinct differences in absorbing chromophore and efficiency of ablation.

Citation Download Citation

Steven L. Jacques, Felix Ejike Ejeckam, and Frank K. Tittel "How micro is microdissection? Laser removal of stratum corneum of skin to expose the epidermal battery", Proc. SPIE 1882, Laser-Tissue Interaction IV, (7 July 1993); https://doi.org/10.1117/12.147667

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available