36 research outputs found
Wound healing study and ablation rate measurements with the novel picosecond infrared laser (PIRL)
We present the first wound healing study in rat skin, showing minimal scar formation with the Picosecond-Infrared-Laser (PIRL) compared to a conventional scalpel and electrosurgical device. In addition, we show first ablation rate measurements
Sampling of Tissues with Laser Ablation for bottom-up Proteomics: Comparison of Picosecond Infrared Laser (PIRL) and Microsecond Infrared Laser (MIRL)
The analysis of proteomes directly from tissues requires the proteins to be released from the cells and their compartments and solubilized, which usually is achieved by mechanical homogenization. It was recently shown, that sampling of tissues with the novel picosecond infrared laser (PIRL) offers higher yields of proteins with respect to the total amount and total number of individual proteins in comparison to mechanical homogenization. Furthermore, proteins obtained from tissues by homogenization with PIRL are significantly less enzymatically degraded, giving improved access to the original composition of proteoforms. The effective cold vaporization of tissue with PIRL is very soft, which is responsible for the phenomenon, that even enzymatic activities of proteins in the tissue aerosol are maintained. In contrast, the energy following irradiation of tissue with microsecond infrared laser (MIRL) pulses is not thermally and acoustically confined to the ablated volume. In this study, PIRL (1 J·cm-2) and MIRL (40-60 J·cm-2) were compared for sampling different tissue types for bottom-up proteomics. We showed that PIRL at low fluence is optimal for soft tissue and desired in scenarios were enzymatic activities of proteins must be maintained as well as were no residual tissue damage is a requirement. MIRL could be well suited for scenarios were enzymatic activities must be suppressed within the intact tissue and thermal and acoustic damage is not a concern.<br /
Picosecond Infrared Laser (PIRL) Application in Stapes Surgery—First Experience in Human Temporal Bones
Objective: Using a contact-free laser technique for stapedotomy reduces the risk of mechanical damage of the stapes footplate. However, the risk of inner ear dysfunction due to thermal, acoustic, or direct damage has still not been solved. The objective of this study was to describe the first experiences in footplate perforation in cadaver tissue performed by the novel Picosecond-Infrared-Laser (PIRL), allowing a tissue preserving ablation. Patients and Intervention: Three human cadaver stapes were perforated using a fiber-coupled PIRL. The results were compared with footplate perforations performed with clinically applied Er:YAG laser. Therefore, two different laser energies for the Er:YAG laser (30 and 60 mJ) were used for footplate perforation of three human cadaver stapes each. Main Outcome Measure: Comparisons were made using histology and environmental scanning electron microscopy (ESEM) analysis. Results: The perforations performed by the PIRL (total energy: 640–1070 mJ) revealed a precise cutting edge with an intact trabecular bone structure and no considerable signs of coagulation. Using the Er:YAG-Laser with a pulse energy of 30 mJ (total energy: 450–600 mJ), a perforation only in the center of the ablation zone was possible, whereas with a pulse energy of 60 mJ (total energy: of 195–260 mJ) the whole ablation zone was perforated. For both energies, the cutting edge appeared irregular with trabecular structure of the bone only be conjecturable and signs of superficial carbonization. Conclusion: The microscopic results following stapes footplate perforation suggest a superiority of the PIRL in comparison to the Er:YAG laser regarding the precision and tissue preserving ablation