Despite current progress achieved in the surgical technique of radical prostatectomy, post-operative complications such as erectile dysfunction and urinary incontinence persist at high incidence ...rates. In this paper, we present a methodology for functional intra-operative localization of the cavernous nerve (CN) network for nerve-sparing radical prostatectomy using near-infrared cyanine voltage-sensitive dye (VSD) imaging, which visualizes membrane potential variations in the CN and its branches (CNB) in real time. As a proof-of-concept experiment, we demonstrate a functioning complex nerve network in response to electrical stimulation of the CN, which was clearly differentiated from surrounding tissues in an in vivo rat prostate model. Stimulation of an erection was confirmed by correlative intracavernosal pressure (ICP) monitoring. Within 10 minutes, we performed trans-fascial staining of the CN by direct VSD administration. Our findings suggest the applicability of VSD imaging for real-time, functional imaging guidance during nerve-sparing radical prostatectomy.
This paper reports the development and system analysis of a laparoscopic system based on structured illumination technique capable of three-dimensional (3-D) reconstruction of porcine intestine ...during surgical anastomosis (connection of tubular structures). A calibration target is used to validate the system performance and results show a depth of field of 20 mm with an accuracy of 0.008 mm and precision of 0.25 mm. The imaging system is used to reconstruct a quantitative 3-D depth measurement of ex vivo porcine bowel tissues to mimic an end-to-end bowel anastomosis scenario. We demonstrate that the system can detect a suture in the tissue and map homogeneous surfaces of the intestine with different tissue pigments, affirming the feasibility for depth quantization for guiding and assisting medical diagnostic decisions in anastomosis surgery.
Leptin and interleukin-1 beta (IL-1β) are two extensively studied biomarkers associated with metabolic syndrome (MetS) and osteoarthritis (OA). Previous studies have mostly focused on either MetS or ...OA alone, with no available data on Vietnamese patients. This study aimed to investigate the levels of leptin and IL-1β in this patient population and explore their association with clinical parameters of MetS and OA. The study included 164 patients with primary knee OA, who were classified into two categories based on the presence of MetS, and 78 healthy controls. The plasma leptin and IL-1β levels were quantified by ELISA and correlated with clinical parameters. Leptin levels were higher in patients with OA (11.50±10.04 ng/mL) than in healthy controls (0.54±0.37 ng/mL) and increased in patients with MetS compared to those without MetS. IL-1β levels were also significantly higher in OA patients (14.63±15.87 pg/mL) than in controls (7.79±5.11 pg/mL), but were not significantly different between the MetS and non-MetS groups. Leptin levels were positively correlated with body mass index, waist-to-hip ratio, visual analogue scale scores, HbA1c and insulin levels, and HOMA-IR index, whereas IL-1β levels were only correlated with insulin levels and HOMA-IR index. ROC curve analysis revealed that leptin and IL-1β levels could distinguish individuals with and without OA (AUC=0.96; 0.88, respectively), and individuals with and without MetS (AUC=0.82; 0.71, respectively). Our findings suggested that both leptin and IL-1β levels were associated with both MetS and OA and may play a critical role in the pathogenesis of MetS-related OA.
Voltage-sensitive dyes (VSDs) are designed to monitor membrane potential by detecting fluorescence changes in response to neuronal or muscle electrical activity. However, fluorescence imaging is ...limited by depth of penetration and high scattering losses, which leads to low sensitivity in vivo systems for external detection. By contrast, photoacoustic (PA) imaging, an emerging modality, is capable of deep tissue, noninvasive imaging by combining near-infrared light excitation and ultrasound detection. Here, we show that voltage-dependent quenching of dye fluorescence leads to a reciprocal enhancement of PA intensity. We synthesized a near-infrared photoacoustic VSD (PA-VSD), whose PA intensity change is sensitive to membrane potential. In the polarized state, this cyanine-based probe enhances PA intensity while decreasing fluorescence output in a lipid vesicle membrane model. A theoretical model accounts for how the experimental PA intensity change depends on fluorescence and absorbance properties of the dye. These results not only demonstrate PA voltage sensing but also emphasize the interplay of both fluorescence and absorbance properties in the design of optimized PA probes. Together, our results demonstrate PA sensing as a potential new modality for recording and external imaging of electrophysiological and neurochemical events in the brain.
Hyperspectral dark-field microscopy (HSDFM) and data cube analysis algorithms demonstrate successful detection and classification of various tissue types, including carcinoma regions in human ...post-lumpectomy breast tissues excised during breast-conserving surgeries.
We expand the application of HSDFM to the classification of tissue types and tumor subtypes in pre-histopathology human breast lumpectomy samples.
Breast tissues excised during breast-conserving surgeries were imaged by the HSDFM and analyzed. The performance of the HSDFM is evaluated by comparing the backscattering intensity spectra of polystyrene microbead solutions with the Monte Carlo simulation of the experimental data. For classification algorithms, two analysis approaches, a supervised technique based on the spectral angle mapper (SAM) algorithm and an unsupervised technique based on the
-means algorithm are applied to classify various tissue types including carcinoma subtypes. In the supervised technique, the SAM algorithm with manually extracted endmembers guided by H&E annotations is used as reference spectra, allowing for segmentation maps with classified tissue types including carcinoma subtypes.
The manually extracted endmembers of known tissue types and their corresponding threshold spectral correlation angles for classification make a good reference library that validates endmembers computed by the unsupervised
-means algorithm. The unsupervised
-means algorithm, with no
information, produces abundance maps with dominant endmembers of various tissue types, including carcinoma subtypes of invasive ductal carcinoma and invasive mucinous carcinoma. The two carcinomas' unique endmembers produced by the two methods agree with each other within
residual error margin.
Our report demonstrates a robust procedure for the validation of an unsupervised algorithm with the essential set of parameters based on the ground truth, histopathological information. We have demonstrated that a trained library of the histopathology-guided endmembers and associated threshold spectral correlation angles computed against well-defined reference data cubes serve such parameters. Two classification algorithms, supervised and unsupervised algorithms, are employed to identify regions with carcinoma subtypes of invasive ductal carcinoma and invasive mucinous carcinoma present in the tissues. The two carcinomas' unique endmembers used by the two methods agree to
residual error margin. This library of high quality and collected under an environment with no ambient background may be instrumental to develop or validate more advanced unsupervised data cube analysis algorithms, such as effective neural networks for efficient subtype classification.
Intestinal anastomosis is a surgical procedure that restores bowel continuity after surgical resection to treat intestinal malignancy, inflammation, or obstruction. Despite the routine nature of ...intestinal anastomosis procedures, the rate of complications is high. Standard visual inspection cannot distinguish the tissue subsurface and small changes in spectral characteristics of the tissue, so existing tissue anastomosis techniques that rely on human vision to guide suturing could lead to problems such as bleeding and leakage from suturing sites. We present a proof-of-concept study using a portable multispectral imaging (MSI) platform for tissue characterization and preoperative surgical planning in intestinal anastomosis. The platform is composed of a fiber ring light-guided MSI system coupled with polarizers and image analysis software. The system is tested on ex vivo porcine intestine tissue, and we demonstrate the feasibility of identifying optimal regions for suture placement.
•The ZnO base layer improves zno:Mg crystallinity of glass/ZnO/ZnO:Mg film.•The bilayer tunes the carrier mobility and seebeck coefficient.•Its power factor (~ 253.5 μW.m − 1K − 2) is higher than ...that of zno:Mg single layer (~ 48.1 μW.m − 1K − 2) .
ZnO:Mg(5 at%)/glass and ZnO:Mg/ZnO/glass thin films with a total thickness of 1000 nm were prepared by direct current sputtering. Crystalline diameter in ZnO:Mg (200 nm)/ZnO (800 nm) improved to 26.5 nm compared with 21.9 nm in ZnO:Mg film. Mg-substitution of Zn-sites in ZnO:Mg shortened the c-axis with an increase in the optical bandgap of the bilayers to 3.35 eV (ZnO, 3.3 eV). Notably, the electrical conductivity of a ZnO:Mg (200 nm)/ZnO (800 nm) layer of 67.5 S cm−1 is superior to ZnO:Mg (1000 nm), 6.7 S cm−1. The charge carrier mobility for this bilayer is 21 cm2V − 1s − 1, at least 2.5 times higher than the best value reported for ZnO or metal-doped ZnO single layers. This increase in the carrier mobility is ascribed to the energy filtering phenomena due to the potential barrier at the ZnO:Mg/ZnO interface. This leads to a superior Seebeck coefficient of the bilayer (-175.2 μV K − 1 at 300 °C), nearly double that of a ZnO:Mg film. The energy filtering process significantly increased its power factor to 253.5 μW m − 1K − 2 at 300 °C, for the hetero-structured bilayer, nearly five times compared with that of ZnO:Mg. Further, it is comparable with power factor values of 100 – 200 μW m − 1K − 2 at 200 – 300 °C reported for other materials with energy filtering processes. Thus, simple cost-effective semiconductor structures with significant improvement in the thermoelectric parameters were achieved in ZnO:Mg/ZnO heterostructures thin film layers.
The radiant exposure of optical irradiation beams with different scanning parameters has been theoretically studied. We analyzed the difference in radiant exposure introduced by Gaussian and top hat ...beams. Various parameters such as scanning pattern, aperture position, beam size and scan spacing were also introduced in this study. We found that Gaussian beams introduce higher calculated radiant exposure to the aperture than top hat beams for certain beam size to aperture size ratios. However, as the scan spacing decreases, the radiant exposure difference calculated from Gaussian and top hat beams diminishes.
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