Real-time Image Feedback Research Articles

Magneto-Acoustic Theranostic Approach: Integration of Magnetomotive Ultrasound Shear Wave Elastography and Magnetic Hyperthermia.

Although magnetically induced hyperthermia has shown great efficiency in the treatment of solid tumors, it is still a challenge to avoid incomplete ablation or overtreatment. In this study, we applied magnetomotive ultrasound shear wave elastography (MMUS-SWE) as a tool for real-time image guidance and feedback in the magnetic hyperthermia (MH) process. We called this new method as magneto-acoustic theranostic approach (MATA). In MATA, a ferromagnetic particle (fMP) was simultaneously used as a thermoseed for MH and a shear wave source for MMUS-SWE. The fMP was excited by a high-frequency magnetic field to induce the heating effect for MH. Meanwhile, the fMP was stimulated by a pulsed magnetic field to generate shear wave propagation for MMUS-SWE. Thus, the changes in elastic modulus surrounding fMP can be used to estimate the therapy effect of MH. The phantom and in vitro experiments were conducted to verify the feasibility of MATA, which has good performance in magnetothermal conversion and treatment efficacy feedback. The shear wave speed of the isolated pork liver changed significantly after the MH process, which varied from about 1.36 to 4.85 m/s. Preliminary results proved that changes in elastic modulus could be useful to estimate the therapy effect of MH. We expect that MATA, which is the integration of MMUS-SWE and MH, will be a novel theranostic method for clinical translation.

Dynamic Virtual Fixture Generation Based on Intra-Operative 3D Image Feedback in Robot-Assisted Minimally Invasive Thoracic Surgery.

This paper proposes a method for generating dynamic virtual fixtures with real-time 3D image feedback to facilitate human-robot collaboration in medical robotics. Seamless shared control in a dynamic environment, like that of a surgical field, remains challenging despite extensive research on collaborative control and planning. To address this problem, our method dynamically creates virtual fixtures to guide the manipulation of a trocar-placing robot arm using the force field generated by point cloud data from an RGB-D camera. Additionally, the "view scope" concept selectively determines the region for computational points, thereby reducing computational load. In a phantom experiment for robot-assisted port incision in minimally invasive thoracic surgery, our method demonstrates substantially improved accuracy for port placement, reducing error and completion time by 50% (p=1.06×10-2) and 35% (p=3.23×10-2), respectively. These results suggest that our proposed approach is promising in improving surgical human-robot collaboration.

Prediction and Prevention of Theft in Jewellery Shop

The internet of Things (IoT)-based total security is the most broadly used protection framework introduced by the technological developments. Sensors and cameras play a vital role in detecting movement and alerting the humans in lots of security applications. As these security gadgets are always accompanied with alarm systems, it is more popularly used for preventing the theft in public places like shopping malls and shops. In such areas, conventional CCTV cameras are usually used as it helps in non-stop human tracking, and detections of crimes. The proposed system is also on such intelligent security system capable of identifying mis-happenings in the public places. With real-time image feedback, the proposed device provides the owner with assurance even when they are not around. These studies examine the possibility of implementing automation technologies in the near future to provide complete protective control. The research suggests a fully automated security system that uses alarm messages and the internet of things (IoT) to predict and prevent unwanted activities in the jewellery shop.

Autonomous Robotic System for Breast Biopsy With Deformation Compensation

Image-guided biopsy is the most common technique for breast cancer diagnosis. Although magnetic resonance imaging (MRI) has the highest sensitivity in breast lesion detection, ultrasound (US) biopsy guidance is generally preferred due to its non-invasiveness and real-time image feedback during the insertion. In this work, we propose an autonomous robotic system for US-guided biopsy of breast lesions identified on pre-operative MRI. After initial MRI to breast registration, the US probe attached to the robotic manipulator compresses the breast tissues until a pre-determined force level is reached. This technique, known as preloading, will allow to minimize lesion displacement during the needle insertion. Our workflow integrates a deformation compensation strategy based on patient-specific biomechanical model to update the US probe orientation keeping the target lesion on the US image plane during compression. By relying on a deformation model, the proposed system does not require lesion visibility on US. Experimental evaluation is performed to assess the performance of the system on a realistic breast phantom with 15 internal lesions, considering different preloading forces. The deformation compensation strategy allows to improve localization accuracy, and as a consequence final probe positioning, for all considered lesions. Median lesion localization error is 3.3 mm, which is lower than the median lesion radius, when applying a preloading of 2 N, which guarantees both minimal needle insertion error and tissue stress.

Automated Manipulation of Microswarms Without Real-Time Image Feedback Using Magnetic Tweezers

Microswarms assembled by microparticles have shown promising prospects in targeted delivery. However, the automated manipulation of microswarms remains a considerable challenge due to the limitations of existing <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in vivo</i> imaging technology. In this article, we design a magnetic tweezer system with a large workspace of 100 mm × 100 mm × 30 mm, which can assemble, transport, and disassemble microswarms efficiently. The magnetic tweezers generate rotating magnetic fields in the workspace, enabling magnetized microparticles to roll toward a specific point along spiral trajectories. The assembly process and mechanism of microswarms are analyzed. The developed system can assemble low-density magnetic microparticles to form a stable and compact microswarm at a predetermined position. Actuation of the magnetic tweezers allows precise navigation of the swarm without relying on real-time image feedback. The experimental results show that the flexible microswarm can achieve satisfactory motion performance and transmission efficiency. The microswarm can successfully move on a slope with an inclination angle of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$40^\circ $</tex-math></inline-formula> and navigate analog channels. The overall delivery efficiency can reach 92%.

A virtual surgical prototype system based on gesture recognition for virtual surgical training in maxillofacial surgery

BackgroundVirtual reality (VR) technology is an ideal alternative of operation training and surgical teaching. However, virtual surgery is usually carried out using the mouse or data gloves, which affects the authenticity of virtual operation. A virtual surgery system with gesture recognition and real-time image feedback was explored to realize more authentic immersion.MethodGesture recognition technology proposed with an efficient and real-time algorithm and high fidelity was explored. The recognition of hand contour, palm and fingertip was firstly realized by hand data extraction. Then, an Support Vector Machine classifier was utilized to classify and recognize common gestures after extraction of feature recognition. The algorithm of collision detection adopted Axis Aligned Bounding Box binary tree to build hand and scalpel collision models. What’s more, nominal radius theorem (NRT) and separating axis theorem (SAT) were applied for speeding up collision detection. Based on the maxillofacial virtual surgical system we proposed before, the feasibility of integration of the above technologies in this prototype system was evaluated.ResultsTen kinds of signal static gestures were designed to test gesture recognition algorithms. The accuracy of gestures recognition is more than 80%, some of which were over 90%. The generation speed of collision detection model met the software requirements with the method of NRT and SAT. The response time of gesture] recognition was less than 40 ms, namely the speed of hand gesture recognition system was greater than 25 Hz. On the condition of integration of hand gesture recognition, typical virtual surgical procedures including grabbing a scalpel, puncture site selection, virtual puncture operation and incision were carried out with realization of real-time image feedback.ConclusionBased on the previous maxillofacial virtual surgical system that consisted of VR, triangular mesh collision detection and maxillofacial biomechanical model construction, the integration of hand gesture recognition was a feasible method to improve the interactivity and immersion of virtual surgical operation training.

Autonomous Robotic Screening of Tubular Structures Based Only on Real-Time Ultrasound Imaging Feedback

Ultrasound (US) imaging is widely employed for diagnosis and staging of vascular diseases, mainly due to its high availability and the fact it does not emit ionizing radiation. However, high interoperator variability limits the repeatability of US image acquisition. To address this challenge, we propose an end-to-end workflow for automatic robotic US screening of tubular structures using only real-time US imaging feedback. First, a U-Net was trained for real-time segmentation of vascular structure from cross-sectional US images. Then, we represented the detected vascular structure as a 3-D point cloud, which was used to estimate the centerline of the target structure and its local radius by solving a constrained nonlinear optimization problem. Iterating the previous processes, the US probe was automatically aligned to the normal direction of the target structure, while the object was constantly maintained in the center of the US view. The real-time segmentation result was evaluated both on a phantom and <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">in vivo</i> on brachial arteries of volunteers. In addition, the whole process was validated using both simulation and physical phantoms. The mean absolute orientation, centering, and radius error ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\pm$</tex-math></inline-formula> SD) on a gel phantom were <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$\text{3.7}\pm \text{1.6}^{\circ }$</tex-math></inline-formula> , <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$0.2\pm \text{0.2}\,\text{mm}$</tex-math></inline-formula> and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">$0.8\pm \text{0.4}\,\text{mm}$</tex-math></inline-formula> , respectively. The results indicate that the method can automatically screen tubular structures with an optimal probe orientation (i.e., normal to the vessel) and accurately estimate the radius of the target structure.

THE COMBINATION OF SHAPE SENSING ROBOTIC BRONCHOSCOPY WITH MOBILE 3D IMAGING TO VERIFY TOOL-IN-LESION AND ASSESS DIVERGENCE

TOPIC: Procedures TYPE: Late Breaking PURPOSE: With recent advances in robotic bronchoscopy for peripheral pulmonary nodule sampling, there has been notable improvements in reach, stability, and precision. However, barriers such as CT to body divergence and sampling error remain. Traditional cone beam systems have been shown to overcome these hurdles, however, this imaging modality is expensive and can have limited availability. The combination of shape-sensing robotic bronchoscopy (SSRAB) and mobile C-arm with CT capabilities could not only enhance the confidence of the pathology results with confirmation of tool-in-lesion for peripheral pulmonary nodules but may also overcome diaphragmatic motion through real-time 3D image feedback to make precise micro-adjustments and optimize outcomes in a transportable fashion. METHODS: A single-center prospective study was conducted to evaluate the combined use of SSRAB with portable cone beam computed tomography to visualize tool-in-lesion as a correlate to diagnostic yield (NCT# 04740047). Fluoroscopy and radiation data were captured. Additionally, data regarding nodule motion during navigation and breath holds were captured to quantify nodule motion and divergence. RESULTS: Twenty-two lesions were captured in 12 males (54.5%) and 10 females (45.5%). The median lesion size was 15 mm (range 10 – 27 mm) with the median airway generation being 7 (range 5-11) and median distance from pleura of 13 mm (range 1 - 45.8 mm). Most lesions were in the left upper lobe (8, 34.8%). Tool-in-lesion was visualized at the time of the procedure in 21 lesions (95.5%). Based on immediate histopathologic review, 14 (63.63%) nodules were malignant and 6 (27.3%) were benign. Two specimens were suggestive of inflammation and are awaiting follow up imaging. Mean number of spins was 2.6 (± 1.8 spins) with a mean fluoroscopy time of 9.1 minutes (± 6.6 minutes) and a mean Dose Area Product of 51.1 Gy*cm2 (± 33.9 Gy*cm2). There were no episodes of bleeding or pneumothorax. Observed CT-body divergence was overcome using the combination of both technologies as evidenced by the tool-in-lesion rate and will be quantified when the entire dataset is available. CONCLUSIONS: The combination of SSRAB and mobile 3D imaging allows for adequate visualization of tool in lesion without the need for a fixed cone beam CT and may improve diagnostic yield. CLINICAL IMPLICATIONS: Shape-sensing robotic technology combined with mobile CT imaging allows for accurate placement of the biopsy tool in the lesion. This combination may enhance diagnostic ability for sampling of peripheral pulmonary nodules and translate well in the applications of therapeutics in the future. Mobile 3D imaging allows for flexibility and maneuverability without the need for an expensive fixed cone beam CT room with adequate image quality. DISCLOSURES: No relevant relationships by Jennifer Duke, source=Web Response No relevant relationships by Eric Edell, source=Web Response No relevant relationships by Sebastian Fernandez-Bussy, source=Web Response No relevant relationships by Ryan Kern, source=Web Response Research grant relationship with Intuitive Surgical Please note: $5001 - $20000 by Janani Reisenauer, source=Web Response, value=Grant/Research Support

Functional Neuroimaging During Asleep DBS Surgery: A Proof of Concept Study.

Object: A real-time functional magnetic resonance imaging (fMRI) feedback during ventral intermediate nucleus (VIM) deep brain stimulation (DBS) under general anesthesia (or “asleep” DBS) does not exist. We hypothesized that it was feasible to acquire a reliable and responsive fMRI during asleep VIM DBS surgery.Methods: We prospectively enrolled 10 consecutive patients who underwent asleep DBS for the treatment of medication-refractory essential tremor. Under general anesthesia, we acquired resting-state functional MRI immediately before and after the cannula insertion. Reliability was determined by a temporal signal-to-noise-ratio >100. Responsiveness was determined based on the fMRI signal change upon insertion of the cannula to the VIM.Results: It was feasible to acquire reliable fMRI during asleep DBS surgery. The fMRI signal was responsive to the brain cannula insertion, revealing a reduction in the tremor network's functional connectivity, which did not reach statistical significance in the group analysis.Conclusions: It is feasible to acquire a reliable and responsive fMRI signal during asleep DBS. The acquisition steps and the preprocessing pipeline developed in these experiments will be useful for future investigations to develop fMRI-based feedback for asleep DBS surgery.

Optimal Design and Implementation of a Novel Two-Dimensional Electromagnetic Navigation System That Allows Focused Heating of Magnetic Nanoparticles

A magnetic drug-targeting system featuring real-time imaging, guidance, and local heating is required for more precise drug targeting and minimization of side effects. In this article, we present a novel electromagnetic navigation and heating system that not only guides and navigates magnetic nanoparticles (MNPs) with real-time imaging feedback, but also uses focused MNP heating to release drugs while monitoring the temperature. The magnetic field amplitude and magnetic gradient play key roles in our integrated system; we enhanced the gradient and field within a field of view of 30 × 30 mm. Performance was examined via simulation employing COMSOL Multiphysics software and verified experimentally. After optimization, the maximum gradients attained on the x and y axes are 4.15 and 2.23 T/m/μ0, respectively, for the electromagnetic actuator mode, and 8.48 T/m/μ0 for the magnetic particle imaging mode. The magnetic field amplitude for heating was 19.70 mT at 100 kHz. We then built a two-dimensional MNPs navigation/heating system to demonstrate the in vitro feasibility of our scheme; this afforded a 1-Hz navigation update rate during MNPs guidance in a Y-shaped channel and locally heated MNPs with temperature monitoring.

Semiautomated optical coherence tomography-guided robotic surgery for porcine lens removal

To evaluate semiautomated surgical lens extraction procedures using the optical coherence tomography (OCT)-integrated Intraocular Robotic Interventional Surgical System. Stein Eye Institute and Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, USA. Experimental study. Semiautomated lens extraction was performed on postmortem pig eyes using a robotic platform integrated with an OCT imaging system. Lens extraction was performed using a series of automated steps including robot-to-eye alignment, irrigation/aspiration (I/A) handpiece insertion, anatomic modeling, surgical path planning, and I/A handpiece navigation. Intraoperative surgical supervision and human intervention were enabled by real-time OCT image feedback to the surgeon via a graphical user interface. Manual preparation of the pig-eye models, including the corneal incision and capsulorhexis, was performed by a trained cataract surgeon before the semiautomated lens extraction procedures. A scoring system was used to assess surgical complications in a postoperative evaluation. Complete lens extraction was achieved in 25 of 30 eyes. In the remaining 5 eyes, small lens pieces (≤1.0mm3) were detected near the lens equator, where transpupillary OCT could not image. No posterior capsule rupture or corneal leakage occurred. The mean surgical duration was 277seconds±42 (SD). Based on a 3-point scale (0=no damage), damage to the iris was 0.33±0.20, damage to the cornea was 1.47±0.20 (due to tissue dehydration), and stress at the incision was 0.97±0.11. No posterior capsule rupture was reported. Complete lens removal was achieved in 25 trials without significant surgical complications. Refinements to the procedures are required before fully automated lens extraction can be realized.

Remotely Actuated Needle Driving Device for MRI-Guided Percutaneous Interventions: Force and Accuracy Evaluation.

This paper presents a 2 degrees-of-freedom (DOF) remotely actuated needle driving device for Magnetic Resonance Imaging (MRI) guided pain injections. The device is evaluated in phantom studies under real-time MRI guidance. The force and torque asserted by the device on the 4-DOF base robot are measured. The needle driving device consists of a needle driver, a 1.2-meter long beaded chain transmission, an actuation box, a robot controller and a Graphical User Interface (GUI). The needle driver can fit within a typical MRI scanner bore and is remotely actuated at the end of the MRI table through a novel beaded chain transmission. The remote actuation mechanism significantly reduces the weight and size of the needle driver at the patient end as well as the artifacts introduced by the motors. The clinician can manually steer the needle by rotating the knobs on the actuation box or remotely through a software interface in the MRI console room. The force and torque resulting from the needle driver in various configurations both in static and dynamic status were measured and reported. An accuracy experiment in the MRI environment under real-time image feedback demonstrates a small mean targeting error (<; 1.5 mm) in a phantom study.

Histotripsy initiates local and systemic immunological response and reduces tumor burden in breast cancer

Abstract Histotripsy is an emerging, non-invasive, and non-thermal tumor ablation method that has been shown to ablate tissues with millimeter precision guided by real-time ultrasound imaging feedback. Histotripsy ablates tissues by focusing high pressure ultrasound pulses to create cavitation, liquefying tissue. By utilizing this mechanism, preliminary data has suggested that Histotripsy could be used to both ablate a primary tumor and to stimulate the immune system to treat metastatic disease. However, there has not been work done to date on investigating the interactions of the immune system with Histotripsy. For the current work, we hypothesized Histotripsy treatment of a 4T1 tumor in a murine model would stimulate local and systemic immune system responses with an improvement on disease burden. Here, we show that Histotripsy was able to reduce the size of the treated tumor, number of metastases, and change the cytokine profiles. Treated tumors had an average of 15% reduction in volume in 24hrs following treatment and showed increases in necrosis and innate immune cell infiltration. Analysis of early response revealed increased pro-inflammatory cytokines, correlating with increased anti-tumor microenvironments. At a long term follow up, Histotripsy decreased disease burden through primary tumor size and metastasis number. These results demonstrate Histotripsy can stimulate an immunological effect with the increased anti-tumor microenvironment in the treated area one day after treatment, and overall disease morbidity in the long term. Histotripsy has promise as an immunomodulating tumor ablation method for breast cancer, and, once established, has the potential to be utilized in different tumor types as well.

Comparison of simulation and experimental results for the deposition orientation in localized electrochemical deposition

Localized electrochemical deposition (LECD) with real-time image feedback distance control (IFDC) was applied to fabricate high-quality three-dimensional (3D) microstructures. The purpose of this study was to determine the relationship between the deposition orientation of the 3D microstructures and the electric field strength by simulation. To predict the deposition orientation of the 3D microstructures, we proposed three methods to analyze the distribution of electric field strength using characteristic directions calculated by the maximum (electric field) strength, weighted average, and midpoint (over a certain threshold value) methods. Compared with the experimental results, the midpoint method with a 50% threshold value provided the best prediction for the deposition orientation. In addition, the deposition orientation did not change significantly when the experiments were performed with different working voltages at the same microelectrode-structure distance.

Magnetic Resonance Imaging-guided High-intensity Focused Ultrasound Applications in Pediatrics: Early Experience at Children's National Medical Center.

Magnetic resonance imaging-guided high-intensity focused ultrasound (MR-HIFU) is a novel technology that integrates magnetic resonance imaging with therapeutic ultrasound. This unique approach provides a completely noninvasive method for precise thermal ablation of targeted tissues with real-time imaging feedback. Over the past 2 decades, MR-HIFU has shown clinical success in several adult applications ranging from treatment of painful bone metastases to uterine fibroids to prostate cancer and essential tremor. Although clinical experience in pediatrics is relatively small, the advantages of a completely noninvasive and radiation-free therapy are especially attractive to growing children. Unlike elderly patients, young children must deal with an entire lifetime of negative effects related to collateral tissue damage associated with invasive surgery, side effects of chemotherapy, and risk of secondary malignancy due to radiation exposure. These reasons provide a clear rationale and strong motivation to further advance clinical utility of MR-HIFU in pediatrics. We begin with an introduction to MR-HIFU technology and the clinical experience in adults. We then describe our early institutional experience in using MR-HIFU ablation to treat symptomatic benign, locally aggressive, and metastatic tumors in children and young adults. We also review some limitations and challenges encountered in treating pediatric patients and highlight additional pediatric applications which may be feasible in the near future.

Fabrication of 3D Microstructure by Localized Electrochemical Deposition with Image Feedback Distance Control and Five-Axis Motion Platform

The localized electrochemical deposition (LECD) process has been used to fabricate 3D microproducts. We combine the LECD process with a real-time 3D image feedback distance control system to improve the quality and conformational design complexity of 3D microproducts. Analyses of microproducts show that the main factor for designing complex 3D microproducts is the deposition direction angle that can be controlled in a 2D fabrication method. The deposition direction angle was the angle between the normal direction of the substrate surface and deposition direction. The normal direction of the substrate surface was determined 0°.We investigate two methods to improve the deposition direction angle in this study. The first method makes use of a new type of micro anode with asymmetric tip. By using this asymmetric micro anode, the deposition direction angle is found to range between −12.0° and 107.9°. This range is only to display the performance of the anode that proposed in this study. The second method is to redesign the moving mechanism and increase actuators and axes. By employing these two methods, we demonstrate high quality fabrication of two types of microstructures: helical springs with low pitch angle and inverted tripods.

Reduction of cue-induced craving through realtime neurofeedback in nicotine users: The role of region of interest selection and multiple visits

This multi-visit, real-time functional magnetic resonance imaging feedback study demonstrates that treatment-seeking smokers can effectively modulate their behavioral and brain responses to smoking cues. They are more effective at decreasing activity in functionally defined regions involved in “craving” (e.g. ventral anterior cingulate cortex (vACC)) rather than increasing activity in regions involved in “resisting” (e.g. dorsal medial prefrontal cortex (dmPFC)).

A forward-imaging needle-type OCT probe for image guided stereotactic procedures

A forward-imaging needle-type optical coherence tomography (OCT) probe with Doppler OCT (DOCT) capability has the potential to solve critical challenges in interventional procedures. A case in point is stereotactic neurosurgery where probes are advanced into the brain based on predetermined coordinates. Laceration of blood vessels in front of the advancing probe is an unavoidable complication with current methods. Moreover, cerebrospinal fluid (CSF) leakage during surgery can shift the brain rendering the predetermined coordinates unreliable. In order to address these challenges, we developed a forward-imaging OCT probe (740 μm O.D.) using a gradient-index (GRIN) rod lens that can provide real-time imaging feedback for avoiding at-risk vessels (8 frames/s with 1024 A-scans per frame for OCT/DOCT dual imaging) and guiding the instrument to specific targets with 12 μm axial resolution (100 frames/s with 160 A-scans per frame for OCT imaging only). The high signal-to-background characteristic of DOCT provides exceptional sensitivity in detecting and quantifying the blood flow within the sheep brain parenchyma in real time. The OCT/DOCT dual imaging also demonstrated its capability to differentiate the vessel type (artery/vein) on rat’s femoral vessels. We also demonstrated in ex vivo human brain that the location of the tip of the OCT probe can be inferred from micro-anatomical landmarks in OCT images. These findings demonstrate the suitability of OCT guidance during stereotactic procedures in the brain and its potential for reducing the risk of cerebral hemorrhage.

Enhancing Surgical Vision by Using Real-Time Imaging of αvβ3-Integrin Targeted Near-Infrared Fluorescent Agent

This study was designed to improve the surgical procedure and outcome of cancer surgery by means of real-time molecular imaging feedback of tumor spread and margin delineation using targeted near-infrared fluorescent probes with specificity to tumor biomarkers. Surgical excision of cancer often is confronted with difficulties in the identification of cancer spread and the accurate delineation of tumor margins. Currently, the assessment of tumor borders is afforded by postoperative pathology or, less reliably, intraoperative frozen sectioning. Fluorescence imaging is a natural modality for intraoperative use by directly relating to the surgeon's vision and offers highly attractive characteristics, such as high-resolution, sensitivity, and portability. Via the use of targeted probes it also becomes highly tumor-specific and can lead to significant improvements in surgical procedures and outcome. Mice bearing xenograft human tumors were injected with αvβ3-integrin receptor-targeted fluorescent probe and in vivo visualized by using a novel, real-time, multispectral fluorescence imaging system. Confirmatory ex vivo imaging, bioluminescence imaging, and histopathology were used to validate the in vivo findings. Fluorescence images were all in good correspondence with the confirming bioluminescence images in respect to signal colocalization. Fluorescence imaging detected all tumors and successfully guided total tumor excision by effectively detecting small tumor residuals, which occasionally were missed by the surgeon. Tumor tissue exhibited target-to-background ratio of ~4.0, which was significantly higher compared with white-light images representing the visual contrast. Histopathology confirmed the capability of the method to identify tumor negative margins with high specificity and better prediction rate compared with visual inspection. Real-time multispectral fluorescence imaging using tumor specific molecular probes is a promising modality for tumor excision by offering real time feedback to the surgeon in the operating room.

Effects of Real-time Imaging on Decision-Making in a Simulated Incident Command Task

Eight Incident Commanders (ICs) took part in a simulation exercise to determine the impact of real-time imaging feedback on situation assessment and decision-making in an uncertain and high-tempo environment. The imaging feedback simulated the video feed from an unmanned aerial vehicle (UAV) that allows incident command centers to monitor developments at the crisis site. Nearly all of the ICs failed to detect important changes in the situation that were not captured in the imaging but that were available via other, more traditional data sources. It appears that the ICs placed an inappropriately high level of trust in the imaging data, resulting in a narrowing of their data search activities and limited cross-checking between the data sources being used. This research helps anticipate and guard against undesirable effects of introducing similar technologies on training and operational procedures in a variety of domains.