Optical design and imaging performance testing of a 9.6-mm diameter femtosecond laser microsurgery probe

Department of Mechanical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA.
Optics Express (Impact Factor: 3.49). 05/2011; 19(11):10536-52. DOI: 10.1364/OE.19.010536
Source: PubMed


We present the optical design of a 9.6-mm diameter fiber-coupled probe for combined femtosecond laser microsurgery and nonlinear optical imaging. Towards enabling clinical use, we successfully reduced the dimensions of our earlier 18-mm microsurgery probe by half, while improving optical performance. We use analytical and computational models to optimize the miniaturized lens system for off-axis scanning aberrations. The optimization reveals that the optical system can be aberration-corrected using simple aspheric relay lenses to achieve diffraction-limited imaging resolution over a large field of view. Before moving forward with custom lenses, we have constructed the 9.6-mm probe using off-the-shelf spherical relay lenses and a 0.55 NA aspheric objective lens. In addition to reducing the diameter by nearly 50% and the total volume by 5 times, we also demonstrate improved lateral and axial resolutions of 1.27 µm and 13.5 µm, respectively, compared to 1.64 µm and 16.4 µm in our previous work. Using this probe, we can successfully image various tissue samples, such as rat tail tendon that required 2-3 × lower laser power than the current state-of-the-art. With further development, image-guided, femtosecond laser microsurgical probes such as this one can enable physicians to achieve the highest level of surgical precision anywhere inside the body.

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Available from: Murat Yildirim, Oct 01, 2015
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    • "Recently, several researchers devoted themselves to design micro laser ablation modules and systems with desired size of laser spot on lesion. Ben-Yakar et al. aimed to decrease the size of the laser ablation module and presented two sets of laser ablation modules with the lengths of 15.0 millimeters and 9.6 millimeters [7], [8], [9]. Gianduzzo et al. investigated a flexible laser ablation module with the diameter of 5.0 millimeters and applied to nerve-sparing radical prostatectomy in the canine model [10]. "
    Intelligent Robots and Systems (IROS 2014), 2014 IEEE/RSJ International Conference on; 09/2014
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    • "Fig. 5. Three generations of endoscopic ultrafast laser surgery probes. Photograph of the (a) 18-mm probe [118] and schematics of the (b) 9.6-mm probe [120] and the (c) 5-mm probe [121]. (d) Two-photon image of a single layer of live breast carcinoma cells after uptake of calcein AM taken prior to irradiation with high intensity pulses (left) and the same immediately after irradiation with a single pulse at 280 nJ pulse energy (right) using the 18-mm probe. "
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