The preparation of small-sized biological samples is traditionally performed manually utilizing mechanical tools such as scalpels. The main drawbacks of such methods are a lack of accuracy and repeatability of the resulting cuts and damage to the surrounding tissue due to the high interaction forces and the accompanying mechanical stresses. One way to circumvent these issues is to substitute the mechanical tools for laser light. When used in conjunction with a high-accuracy positioning system, such a preparation procedure enables repeatable cutting of arbitrary geometries while largely preserving the integrity of the surrounding tissue. In this paper, a system leveraging the potential of laser-based ablation for bio-sample preparation is proposed. It integrates and synchronizes all key components with extensive safety features and an intuitive user interface, allowing novice operators to perform sample preparations easily. As a first application, the proposed system has been utilized to create microdamages in mouse tail tendon fascicles. Promising results could be obtained, but careful tuning of the laser parameters and further optimization of the mechanical setup is still required to attain the high repeatability striven for.

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A novel real-time and non-destructive method for differentiating soft from hard tissue in laser osteotomy has been introduced and tested in a closed-loop fashion. Two laser beams were combined: a low energy frequency-doubled nanosecond Nd:YAG for detecting the type of tissue, and a high energy microsecond Er:YAG for ablating bone. The working principle is based on adjusting the energy of the Nd:YAG laser until it is low enough to create a microplasma in the hard tissue only (different energies are required to create plasma in different tissue types). Analyzing the light emitted from the generated microplasma enables real-time feedback to a shutter that prevents the Er:YAG laser from ablating the soft tissue.

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The aim of this paper is to examine the effect of pig bone immersion in different levels of cooling water during laser ablation with a Er:YAG laser. The laser worked at 2940 nm wavelength and 10 Hz repetition rate in microseconds pulse duration regime. The bone was immersed in different levels of cooling water in a sample container for preventing carbonization. The bone samples were ablated with fixed deposited energy to investigate at which water level Er:YAG lasers start ablating bone through a layer of water. Results showed that the maximum level of water that laser can pass through to start the ablation nonlinearly depends on pulse energy.

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The aim of the present study is to investigate the effect of laser pulse duration on ablation efficiency of hard bones. The bones were ablated using a microsecond pulsed Er-YAG laser. The laser wavelength was 2.94 μm and the repetition rate was 10Hz. Three samples of porcine femur were used and several areas were ablated with a fixed pulse energy of 280mJ and different pulse durations. The ablation procedure was applied during five seconds for all the experiments, therefore, the same amount of energy (14 J) was deposited in each trial. The ablation efficiency was determined by measuring the ablated volume per second for each experiment.@en