We developed an integrated dual-modal photoacoustic and optical coherence tomography (PA-OCT) system using a single near-infrared supercontinuum laser source to simultaneously provide both optical absorption and scattering contrasts. A pulsed broadband supercontinuum source was generated by a pulsed Nd:YAG laser and a photonic-crystal fiber. When we imaged two colored hairs, the black hair was visible in both PA and OCT images, whereas the white hair was only mapped in the OCT image. The single laser source will potentially allow us to implement relatively simple, cheap, and compact dual-modal PA-OCT systems, which are key criteria for fast clinical translation and commercialization.

This study was designed to examine the developmental ability of porcine embryos after somatic cell nuclear transfer. Porcine fibroblasts were isolated from fetuses at Day 40 of gestation. In vitro-matured porcine oocytes were enucleated and electrically fused with somatic cells. The reconstructed eggs were activated using electrical stimulus and cultured in vitro for 6 days. Nuclear-transferred (NT) embryos activated at a field strength of 120 V/mm (11.6 +/- 1.6%) showed a higher developmental rate as compared to the 150-V/mm group (6.5 +/- 2.3%) (P: < 0.05), but the mean cell numbers of blastocysts were similar between the two groups. Rates of blastocyst development from NT embryos electrically pulsed at different times (2, 4, and 6 h) after electrofusion were 11.6 +/- 2.9, 6.6 +/- 2.3, and 8.1 +/- 3.3%, respectively. The mean cell numbers of blastocysts developed from NT embryos were gradually decreased (30.4 +/- 10.4 > 24.6 +/- 10.1 > 16.5 +/- 7.4 per blastocyst) as exposure time (2, 4, and 6 h) of nuclei to oocyte cytoplast before activation was prolonged. There was a significant difference in the cell number between the 2- and 6-h groups (P: < 0. 05). Nuclear-transferred embryos (9.4 +/- 0.9%) had a lower developmental rate than in vitro fertilization (IVF)-derived (21.4 +/- 1.9%) or parthenogenetic embryos (22.4 +/- 7.2%) (P: < 0.01). The mean cell number (28.9 +/- 11.4) of NT-derived blastocysts was smaller than that (38.6 +/- 10.4) of IVF-derived blastocysts (P: < 0. 05) and was similar to that (29.9 +/- 12.1) of parthenogenetic embryos. Our results suggest that porcine NT eggs using somatic cells after electrical activation have developmental potential to the blastocyst stage, although with smaller cell numbers compared to IVF embryos.

We developed a virtual intraoperative surgical photoacoustic microscopy system by combining with a commercial surgical microscope and photoacoustic microscope (PAM). By sharing the common optical path in the microscope and PAM system, we could acquire the PAM and microscope images simultaneously. Moreover, by employing a beam projector to back-project 2D PAM images onto the microscope view plane as augmented reality, the conventional microscopic and 2D cross-sectional PAM images are concurrently mapped on the plane via an ocular lens of the microscope in real-time. Further, we guided needle insertion into phantom ex vivo and mice skins in vivo. A surgical microscope is a vital tool during operations since it started being used in otolaryngology.1,2 In spite of the continuous improvement of the surgical microscopy performance, it could mainly provide the enlarged surface images without the sub-surface information. Because of this limitation, surgeons are required to have significant experiences and heavy trainings in current clinical practices. Thus, noninvasive visualization of the sub-surface information should play an important role during ophthalmic, microvascular, and neuro-surgeries. 3-5Conventional optical microscopic techniques such as optical coherence tomography (OCT) and fluorescence microscopy (FM) has been applied for this purpose.6-10 OCT mainly provide microstructures of tissues based on optical scattering while the penetration depth of FM is significantly shallow and requires to use the exogenous contrast agents. However, real-time noninvasive mapping of microvasculatures are crucial to verify bleeding regions, guide vascular reconnection, or delineate angiogenesis during the surgeries. 11 To meet this purpose, we are convinced to develop a noninvasive surgical microscopy system to image microvasculatures and surgical intervention without any contrast agent beyond the skin surface in real-time.Photoacoustic microscopy (PAM) is a rising imaging technique that combines optical excitation and ultrasound detection.12-14 Because PAM can provide label-free optical absorption information in a non-invasive manner with high contrast and resolution, this modality has widely been used to image tumor angiogenesis, tumor metabolism, brain function, ocular structures, molecular information, etc. [15][16][17][18][19][20] In this letter, we developed a near-real-time virtual intraoperative surgical photoacoustic microscope (VISPAM) by integrating PAM and conventional surgical microscopy. The VISPAM system could obtain, process, and display both PAM and microscopic images at the same time. The Hilberttransformed cross-sectional PAM B-scan images were projected back onto the microscope view plane as augmented reality through a home-made optical beam splitter, and then the PAM images were shown via the ocular lens mounted on the microscope. Thus, an additional tabletop display is unnecessary, so it is significantly convenient because surgeons potentially do not need to move their sights during the surgeries. We demo...

An intraoperative surgical microscope is an essential tool in a neuro- or ophthalmological surgical environment. Yet, it has an inherent limitation to classify subsurface information because it only provides the surface images. To compensate for and assist in this problem, combining the surgical microscope with optical coherence tomography (OCT) has been adapted. We developed a real-time virtual intraoperative surgical OCT (VISOCT) system by adapting a spectral-domain OCT scanner with a commercial surgical microscope. Thanks to our custom-made beam splitting and image display subsystems, the OCT images and microscopic images are simultaneously visualized through an ocular lens or the eyepiece of the microscope. This improvement helps surgeons to focus on the operation without distraction to view OCT images on another separate display. Moreover, displaying the OCT live images on the eyepiece helps surgeon's depth perception during the surgeries. Finally, we successfully processed stimulated penetrating keratoplasty in live rabbits. We believe that these technical achievements are crucial to enhance the usability of the VISOCT system in a real surgical operating condition.

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