| Autor: |
Sharon L. Thomsen, Helene Vijverberg, Tom J. McMurray, John A. Pearce |
| Rok vydání: |
1993 |
| Předmět: |
|
| Zdroj: |
Lasers in Otolaryngology, Dermatology, and Tissue Welding. |
| ISSN: |
0277-786X |
| DOI: |
10.1117/12.147029 |
| Popis: |
Thermal fusion or welding of collagen-rich tissues involves the thermal denaturation of collagen which is reflected by changes in birefringence intensity in histologic sections. The weld bond between two severed edges is formed when the apposed ends of the collagen fibrils unravel during heating then re-entwine during the cooling phase. Thermal coagulation of collagen can be described as an end point of a kinetic rate process of thermal damage which is linear with time of exposure and exponential with temperature. The kinetic rate coefficients, A (s-1) and E (J/mole), have been experimentally determined for birefringence loss in rat skin collagen heated in vitro -- A equals 1.606 X 1045 and E equals 3.06 X 105. Loss in collagen birefringence is a rare quantitative indicator of thermal damage; in this case, the structural alteration in tissue native-form collagen. The kinetic model coefficients were derived from exposure times between 600 and 6000s over the temperature range 45 to 90 degree(s)C. Room temperature control specimens were also analyzed for comparison. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
|
