In vivo laser cartilage reshaping with carbon dioxide spray cooling in a rabbit ear model: A pilot study. Issue 10 (18th November 2014)

• Record Type: Journal Article
• Authors: Kuan, Edward C.; Hamamoto, Ashley A.; Sun, Victor; Nguyen, Tony; Manuel, Cyrus T.; Protsenko, Dmitry E.; Wong, Brian J. F.; Nelson, J. Stuart; Jia, Wangcun
• Is Part Of: Lasers in surgery and medicine. Volume 46:Issue 10(2014)
• Page Start: 791
• Page End: 795
• Publication Date: 2014-11-18
• Subjects: Lasers in medicine -- Periodicals; Lasers in surgery -- Periodicals; 617
• DOI: 10.1002/lsm.22305
• Languages: English
• ISSNs: 0196-8092

Abstract

<abstract abstract-type="main" xml:lang="en"> <title> <x xml:space="preserve">Abstract</x> </title> <sec id="lsm22305-sec-0001" sec-type="section"> <title>Background/Objectives</title> <p>Similar to conventional cryogen spray cooling, carbon dioxide (CO<sub>2</sub>) spray may be used in combination with laser cartilage reshaping (LCR) to produce cartilage shape change while minimizing cutaneous thermal injury. Recent <italic>ex vivo</italic> evaluation of LCR with CO<sub>2</sub> cooling in a rabbit model has identified a promising initial parameter space for in vivo safety and efficacy evaluation. This pilot study aimed to evaluate shape change and cutaneous injury following LCR with CO<sub>2</sub> cooling in 5 live rabbits.</p> </sec> <sec id="lsm22305-sec-0002" sec-type="section"> <title>Study Design/Materials and Methods</title> <p>The midportion of live rabbit ears were irradiated with a 1.45 µm wavelength diode laser (12 J/cm<sup>2</sup>) with simultaneous CO<sub>2</sub> spray cooling (85 millisecond duration, 4 alternating heating/cooling cycles per site, 5 to 6 irradiation sites per row for 3 rows per ear). Experimental and control ears (no LCR) were splinted in the flexed position for 30 days following exposure. A total of 5 ears each were allocated to the experimental and control groups.</p> </sec> <sec id="lsm22305-sec-0003" sec-type="section"> <title>Results</title> <p>Shape change was observed in all irradiated ears (mean 70 ± 3°), which was statistically different from control (mean 37 ± 11°, <italic>P</italic> = 0.009). No significant thermal cutaneous injury was observed, with preservation of the full thickness of skin, microvasculature, and adnexal structures. Confocal microscopy and histology demonstrated an intact and viable chondrocyte population surrounding irradiated sites.</p> </sec> <sec id="lsm22305-sec-0004" sec-type="section"> <title>Conclusions</title> <p>LCR with CO<sub>2</sub> spray cooling can produce clinically significant shape change in the rabbit auricle while minimizing thermal cutaneous and cartilaginous injury and frostbite. This pilot study lends support for the potential use of CO<sub>2</sub> spray as an adjunct to existing thermal‐based cartilage reshaping modalities. An <italic>in vivo</italic> systematic evaluation of optimal laser dosimetry and cooling parameters is required. Lasers Surg. Med. 46:791–795, 2014. © 2014 Wiley Periodicals, Inc.</p> </sec> </abstract>