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Minimally invasive techniques have revolutionized surgery by reducing surgical trauma and therefore hospital stay and subsequently cost. There are limitations, however. Robot-assisted surgery endeavours to minimize these technical hindrances and so allow better, more precise surgical practise while still minimizing surgical trauma.
The introduction of laparoscopic surgery offers clear advantages to patients; to surgeons, it presents the challenge of learning new remote operating techniques quite different from traditional operating. Telemanipulation, introduced in the late 1990s, was a major advance in overcoming the reduced dexterity introduced by laparoscopic techniques. This paper reviews the development of robotic systems in surgery and their role in the operating room of the future.
The aim of the present study was to assess whether a telemicroscopy system based on static imaging could provide a remote intraoperative frozen section service. Three pathologists evaluated 70 consecutive frozen section cases (for a total of 210 diagnoses) using a static telemicroscopy system (STeMiSy) and light microscopy (LM). STeMiSy uses a robotic microscope, enabling full remote control by consultant pathologists in a near real-time manner. Clinically important concordance between STeMiSy and LM was 98.6% (95.2% overall concordance), indicating very good agreement. The rates of deferred diagnoses given by STeMiSy and LM were comparable (11.0% and 9.5%, respectively). Compared with the consensus diagnosis, the diagnostic accuracy of STeMiSy and LM was 95.2% and 96.2%. The mean viewing time per slide was 3.6 minutes, and the overall time to make a diagnosis by STeMiSy was 6.2 minutes, conforming to intraoperative practice requirements. Our study demonstrates that a static imaging active telepathology system is comparable to dynamic telepathology systems and can provide a routine frozen section service.
Exoskeleton robots are mechanical constructions attached to human body parts, containing actuators for influencing human motion. One important application area for exoskeletons is human motion support, for example, for disabled people, including rehabilitation training, and for force enhancement in healthy subjects. This paper surveys two exoskeleton systems developed in our laboratory. The first system is a lower-extremity exoskeleton with one actuated degree of freedom in the knee joint. This system was designed for motion support in disabled people. The second system is an exoskeleton for a human hand with 16 actuated joints, four for each finger. This hand exoskeleton will be used in rehabilitation training after hand surgeries. The application of EMG signals for motion control is presented. An overview of the design and control methods, and first experimental results for the leg exoskeleton are reported.
Transcranial Doppler Sonography (TCD) monitoring was carried out in 12 healthy subjects (mean age: 35.2 +/- 4.4 years; range: 26-41 years; 4 women, 8 men), prior to, during and following acupuncture. In all subjects an identical acupuncture scheme with a "general increase in Qi energy" setting was employed. Measurements were obtained with new robotic TCD probes enabling three-dimensional imaging of the middle cerebral artery by the use of the multi-scan technique. The results showed a significant (p < 0.01; ANOVA; Tukey test) increase in mean bloodflow velocity measured simultaneously at different depths within the right middle cerebral artery. Quantifiable changes in the physiological effects of acupuncture may contribute to improved acceptance of this unconventional complementary medical procedure.
During the robotic enhanced minimally invasive cardiac surgery the approach to and the space for handling instruments in the operating field are usually reduced, compared to the conventional surgery. Additional well knewn problems are the restricted capability available for accessories into and out of the closed chest and the limited assistance during the cardiac procedure. This paper is presenting two solutions of Miniature Modules for supporting the surgeon inside the closed chest. A self-sufficient Cargo Module is developed as a transportation and depot device. It provides an "inside equipment store" for the surgeon. With the Assist Module the surgical equipment, tissue and vessels can be positioned on a desired place in the operating field. This module provides the surgeon an "assistant" inside the closed chest.
This paper argues for the development of synthetic approaches towards the study of brain and behavior as a complement to the more traditional empirical mode of research. As an example we present our own work on learning and problem solving which relates to the behavioral paradigms of classical and operant conditioning. We define the concept of learning in the context of behavior and lay out the basic methodological requirements a model needs to satisfy, which includes evaluations using robots. In addition, we define a number of design principles neuronal models should obey to be considered relevant. We present in detail the construction of a neural model of short- and long-term memory which can be applied to an artificial behaving system. The presented model (DAC4) provides a novel self-consistent implementation of these processes, which satisfies our principles. This model will be interpreted towards the present understanding of the neuronal substrate of memory.
Experimental evidence suggests that the hippocampus represents locations within an allocentric representation of space. The environmental inputs that underlie the rat's representation of its own location within an environment (in the firing of place cells) are the distances to walls, and different walls are identified by their allocentric direction from the rat. We propose that the locations of goals in an environment is stored downstream of the place cells, in the subiculum. In addition to firing rate coding, place cells may use phase coding relative to the theta rhythm of the EEG. In some circumstances path integration may be used, in addition to environmental information, as an input to the hippocampal system. A detailed computational model of the hippocampus successfully guides the navigation of a mobile robot. The model's behaviour is compared to electrophysiological and behavioural data in rats, and implications for the role of the hippocampus in primates are explored.
BACKGROUND: The implementation of a total endoscopic coronary surgery on the beating heart with the aid of the Da Vinci surgical system (Intuitive, Sunnyvale, CA) requires a stepwise learning process. After cadaveric training and clinical start of the program in November 2002, we gained experience with arrested heart procedures starting in May 2003. In November 2003, we moved to beating heart surgery. METHODS: From November 2003 to January 2005, 14 patients with coronary artery disease (mean age of 62 +/- 5 years, female to male ratio 2:12) were operated with the intention to perform a beating heart TECAB (totally endoscopic coronary artery bypass grafting) procedure. RESULTS: Total conversion rate was 35% (5/14), due to pleural adhesions in 2 patients, injury of the lung during port placement, inability to occlude the LAD with saddle loops, atherosclerotic diseased mammary artery in 1 patient each. Mean operating time was 298 +/- 110 minutes with a steady decline throughout the study period (first 5 patients: 342 +/- 61 minutes, patients 6 to 9: 337 +/- 87 minutes, last 4 patients: 290 +/- 53 minutes), resulting in a 60 minute shorter operating time. Mean ICU stay was 1.3 days and hospital stay lasted on average 8.4 +/- 2.8 days. CONCLUSION: Total endoscopic bypass surgery on the beating heart with the Da Vinci surgical system can be safely implemented in clinical use. The learning curve results in a constantly decreasing procedure time due to a more effective table team-console surgeon-robotic system interaction and a moderate conversion rate.
Radical retropubic prostatectomy is the current gold standard for surgical removal of the prostate gland. Recently, laparoscopic radical prostatectomy has been developed in an attempt to decrease surgical morbidity, and the technical difficulty of laparoscopy has been countered with the development of the da Vinci robotic interface. Studies that have compared the minimally invasive approaches with the traditional open approach have reported comparable perioperative outcomes. While long-term oncological data are available for open prostatectomy, there are only short-term studies available for laparoscopic prostatectomy. Functional outcomes, including urinary continence and sexual function, appear to be similar between the surgical approaches in the short term. However, currently, costs appear to favor open surgery, with the da Vinci-assisted prostatectomy having the highest expenses. Longer-term data are required to confidently determine the optimal balance between morbidity, oncological efficacy, functional outcomes and cost among the differing surgical approaches.
Recent advances in interventional cardiology and cardiac surgery have changed traditional therapeutic algorithms by altering indications, timing and patterns of referral for subsequent surgical treatment. Developments in coronary revascularization have focused on reducing both surgical invasiveness and trauma. Patients with significant comorbid pathologies, those undergoing reinterventions and especially the elderly may benefit from such hybrid procedures by avoiding cardiopulmonary bypass and a midline sternotomy. Minimally invasive techniques have revolutionized cardiothoracic surgery by increasing patient satisfaction and by reducing surgical trauma, hospital stay, and consequently overall costs. There are, however, limitations, but robot-assisted surgery endeavors to minimize these technical hindrances and thus allow better and more accurate surgical practice whilst minimizing surgical trauma.
PURPOSE: Immediate urinary continence (UC) recovery following Retzius-sparing robot-assisted radical prostatectomy (RS-RARP) remains highly variable, highlighting the need for reliable preoperative prediction. We aimed to develop and validate models to identify patients likely to achieve immediate UC recovery following RS-RARP. MATERIALS AND METHODS: A total of 580 prostate cancer patients who underwent RS-RARP from four medical centers were assigned to a training set (n=348), an internal validation set (n=103) and an external validation set (n=129). Independent predictors were identified through univariate analysis and LASSO regression. A nomogram was constructed using multivariate logistic regression. Its performance was evaluated with receiver operating characteristic (ROC) curve, calibration curves, and decision curve analysis. RESULTS: Immediate UC recovery was observed in 84.5% (294/348) of patients in the training cohort, 80.6% (83/103) in the internal validation cohort, and 81.4% (105/129) in the external validation cohort, respectively. Multivariate analysis identified membranous urethral length (MUL) (OR=1.23, P=0.029) and urethral curvature (OR=2.84, P<0.001) as independent predictors, while prostate volume (PV) (OR=0.84, P <0.001) as a protective factor. The nomogram integrating MUL, PV, and urethral curvature demonstrated superior predictive accuracy, with an AUC of 0.87 (95% CI, 0.83-0.91) in the training cohort. The bootstrap-corrected calibration slope was 0.96, and the Brier score was 0.08. Calibration curves and decision curve analysis confirmed the predictive accuracy and clinical utility of the nomogram. CONCLUSIONS: Our study introduces a novel quantitative method for assessing urethral curvature. The mpMRI-based model, integrating urethral curvature and prostate spatial configuration, offers enhanced predictive accuracy for postoperative immediate UC recovery.
BACKGROUND: An analysis of contemporary total knee arthroplasty reveals that, on the average, patients rarely flex the knee beyond 120 degrees. The biomechanical mechanisms that inhibit further flexion after total knee arthroplasty are unknown. The objective of the present study was to investigate the capability of a single design of a fixed-bearing, high-flexion posterior stabilized total knee arthroplasty system (LPS-Flex) to restore the range of flexion to that of the intact knee. METHODS: Thirteen cadaveric human knees were tested, with use of a robotic testing system, before and after total knee arthroplasty with the LPS-Flex prosthesis. The passive path and the kinematics under an isolated quadriceps force of 400 N, under an isolated hamstring force of 200 N, and with these forces combined were determined. Posterior femoral translation of the lateral and medial femoral condyles and tibial rotation were recorded from 0 degrees to 150 degrees of flexion. RESULTS: The medial and lateral condyles of the intact knee translated posteriorly from full extension to 150 degrees, reaching a mean peak (and standard deviation) of 22.9 +/- 11.3 mm and 31.9 +/- 12.5 mm, respectively, under the combined muscle forces. Following total knee arthroplasty, the amount of posterior femoral translation was lower than that observed in the intact knee. At 150 degrees, approximately 90% of the intact posterior femoral translation was recovered by the total knee replacement. Internal tibial rotation was observed for all knees throughout the range of motion. The cam-spine mechanism engaged at approximately 80 degrees and disengaged at 135 degrees. Despite the absence of cam-spine engagement, further posterior femoral translation occurred from 135 degrees to 150 degrees. CONCLUSIONS: The tibiofemoral articular geometry of the intact knee and the knee after total knee arthroplasty with use of the LPS-Flex design demonstrated similar kinematics at high flexion angles. The cam-spine mechanism enhanced posterior femoral translation only at the mid-range of flexion. The femoral component geometry of the LPS-Flex total knee prosthesis may improve posterior tibiofemoral articulation contact in high flexion angles.
With the goal of achieving an intelligent robot camera system that can take dynamic images automatically through humanlike, natural camera work, we analyzed how images were shot, subjectively evaluated reproduced images, and examined effects of camerawork, using camera control technique as a parameter. It was found that (1) A high evaluation is obtained when human-based data are used for the position adjusting velocity curve of the target; (2) Evaluation scores are relatively high for images taken with feedback-feedforward camera control method for target movement in one direction; (3) Keeping the target within the image area using the control method that imitates human camera handling becomes increasingly difficult when the target changes both direction and velocity and becomes bigger and faster, and (4) The mechanical feedback method can cope with rapid changes in the target's direction and velocity, constantly keeping the target within the image area, though the viewer finds the image rather mechanical as opposed to humanlike.
Computer-assisted surgery (CAS) may allow surgeons to be more precise and minimally invasive, in addition to being an excellent research tool. Medical imaging, such as magnetic resonance and computed tomography is not only an important diagnostic tool, but also a necessary planning tool. In orthopaedic sports medicine, precision is needed when placing tunnels for soft tissue fixation of replacement grafts. Two types of CAS systems -- passive and active -- have been developed. Passive systems, or surgical navigation systems, provide the surgeon with additional information prior to and during the surgical procedure (in real time). Active systems have the ability of performing certain surgical steps autonomously. Both active and passive CAS systems are currently a subject of basic science and clinical investigations and will be discussed and commented on in this article. In summary, passive navigation systems can provide additional information to the surgeon and can therefore lead to more precise tunnel placement. Active robotic technology seems to be accurate and feasible with promising initial results from Europe. However, active and passive CAS can only be as precise as the surgeon who plans the procedure. Therefore, future studies have to focus on integrating, arthroscopy, 3-D image-enhanced computer navigation, and virtual kinematics, as well as to increase precision in surgical techniques.
An assay method for identification of metabolites from in vitro microsomal incubations was developed for use in the early stage of drug discovery. We have developed a practical approach which involves integrated sample generation, sample preparation, bioanalysis, and data handling to maximize sample throughput and speed up the process for identification of metabolites. The assay system consisted of a robotic liquid handler (Genesis workstation) to generate and process samples, PALLAS MetabolExpert software to predict possible metabolites, exact mass measurement via a tandem quadrupole time-of-flight mass spectrometer (QTOF-MS) coupled with liquid chromatography to analyze samples, MetaboLynx software to find potential metabolites and Advanced Chemistry Development/MS (ACD/MS) software to provide guidance to the most likely hypothetical metabolite chemical structures. For purposes of evaluating this new method, dextromethorphan, alprenolol, and propranolol were incubated separately for up to 60 minutes with rat and human hepatic microsomes. The incubation and sample preparation were carried out in 96-well plates using the Genesis workstation. The bioanalysis was performed by LC-MS/MS using QTOF with MetaboLynx software to find metabolites. Metabolic products formed in vitro by rat and human microsomes were separated using an analytical column C18 with gradient elution at flow rate of 250 micro l/min. The internal mass calibration was performed by continuous postcolumn infusion of Haloperidol. The mass spectra from incubations containing NADPH were compared to those without NADPH (control) using the MetaboLynx software to find potential metabolites. Finally, the MS/MS spectra were processed by the ACD/MS software to predict the chemical structure. MetaboLynx software successfully identified metabolites for each of the drugs studied by automatically discerning expected metabolites. Exact differences in masses between each metabolite and parent drug were measured from five replicate sample injections. All measured values are accurate to less than 0.001Da or 3.8 ppm with the standard deviation within 0.0015 Da, which allowed good prediction/confirmation of empirical formulae. Hypothetical chemical structures were achieved by the ACD/MS software and provided a useful tool to assist in prediction of the metabolic pathways of the drugs. The metabolites identified were in good agreement with previously published results for all three compounds. This new method will greatly enhance throughput, which in turn will facilitate our ability to rapidly provide this guidance to the synthetic chemist.
Studies of the control of position and movement of the abdomen of crayfish illustrate a number of features of invertebrate sensory-motor systems that have implications for their use to inform robotic design. We use the abdominal slow extensor motor system to illustrate three of them here: first, the way in which a behaviorally flexible length-servo device can be achieved with very few elements; second, the importance of knowledge of the biological and behavioral context in which the elements operate; third, that design solutions resulting from natural selection have been constrained by the previous evolutionary history of the animal, which can affect the outcomes in ways that may not be immediately apparent in a design context.
Engineers have a lot to gain from studying biology. The study of biological neural systems alone provides numerous examples of computational systems that are far more complex than any man-made system and perform real-time sensory and motor tasks in a manner that humbles the most advanced artificial systems. Despite the evolutionary genesis of these systems and the vast apparent differences between species, there are common design strategies employed by biological systems that span taxa, and engineers would do well to emulate these strategies. However, biologically-inspired computational architectures, which are continuous-time and parallel in nature, do not map well onto conventional processors, which are discrete-time and serial in operation. Rather, an implementation technology that is capable of directly realizing the layered parallel structure and nonlinear elements employed by neurobiology is required for power- and space-efficient implementation. Custom neuromorphic hardware meets these criteria and yields low-power dedicated sensory systems that are small, light, and ideal for autonomous robot applications. As examples of how this technology is applied, this article describes both a low-level neuromorphic hardware emulation of an elementary visual motion detector, and a large-scale, system-level spatial motion integration system.