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A small, hermetic, wirelessly-controlled retinal prosthesis was developed for pre-clinical studies in Yucatan mini-pigs. The device was implanted on the outside of the eye in the orbit, and it received both power and data wirelessly from external sources. The prosthesis drove a sub-retinal thin-film array of sputtered iridium oxide stimulating electrodes. The implanted device included a hermetic titanium...
This paper presents the control architecture and the first performance evaluation results of a novel and highly-dexterous 18 degrees of freedom (DOF) miniature master/slave teleoperated robotic system called SPRINT (Single-Port la-paRoscopy bimaNual roboT). The system was evaluated in terms of positioning accuracy, repeatability, tracking error during local teleoperation and end-effector payload....
Hemorrhagic stroke accounts for more than 15% of all stroke hospitalization with much higher mortality than ischemic stroke. In this study, we investigated the spatiotemporal changes of the cerebral blood flow (CBF) following intracerebral hemorrhagic (ICH) stroke by laser speckle imaging. Adult male C57BL/6 mice were divided into ICH group (n=7) and saline group (n=4). CBF images were recorded before...
In this paper, we propose the use of black box models for the system identification of the cardiopulmonary baroreflex control of arterial resistance and of ventricular contractility and of arterial baroreflex control of heart rate (HR) from invasive, continuous measurements of arterial blood pressure (ABP) and central venous pressure (CVP), and non invasive, continuous recordings of ECG and respiration...
In this paper we discuss an efficient methodology for the characterization of Microelectrode Recordings (MER) obtained during deep brain stimulation surgery for Parkinson's disease using Support Vector Machines and present the results of a preliminary study. The methodology is based in two algorithms: (1) an algorithm extracts multiple computational features from the microelectrode neurophysiology,...
Electroencephalogram (EEG) is an important component of the pre-surgical evaluation in the treatment of medically intractable epilepsy. However, clinical EEG uses 19 to 32 electrodes that significantly limits its localization ability. Recent development of dense-array recording techniques has suggested that increased spatial sampling rate improves the accuracy of source localization. In the current...
This paper introduces ongoing research on computer-aided ophthalmic surgery. In particular, a novel Content-Based Video Retrieval (CBVR) system is presented. Its purpose is the following: given a video stream captured by a digital camera monitoring the surgery, the system should retrieve, in real-time, similar video subsequences in video archives. In order to retrieve semantically-relevant videos,...
The main purpose of this paper is to show the potential of tissue motion estimation in ultrasound imaging for the diagnostic of pelvic floor disorders. We propose to evaluate the tissue motion using a method based on a local deformable model and on image features (local phase and orientation) extracted from the monogenic signal. The proposed method is well adapted to the pelvic organ deformations...
For any image guided surgery, independently of the technique which is used (navigation, templates, robotics), it is necessary to get a 3D bone surface model from CT or MR images. Such model is used for planning, registration and visualization. We report that graphical representation of patient bony structure and the surgical tools, interconnectively with the tracking device and patient-to-image registration...
This paper presents the analysis of the autonomic nervous system (ANS) control and cardiac baroreflex sensitivity in patients undergoing general anesthesia for major surgery, with the goal of evaluating the effects of anesthesia bolus induction with propofol on autonomic control of heart rate (HR) and arterial blood pressure (ABP). The increase in baroreflex gain in the LF band observed through two...
This study investigated the feasibility of chronically recording descending signals from the rat spinal cord using microwire electrodes. Eight 25μm diameter Pt-Ir microwires were implanted in the dorsolateral rubrospinal tract (RST) bilaterally at the c5 level in each of the four adult Long Evans rats trained for food reach-to-grasp task. Signal stability was assessed by calculating the signal-to-noise...
Recent development methods for surgical robots have an inherent problem. The user-friendliness of operating robot cannot be revealed until completion of the robot. To assist the design of a surgical robot that is user-friendly in terms of surgeon's operation, we propose a system that considers the operation manner of surgeon during the design phase of the robot. This system includes the following...
Image-guided surgical navigation is on the rise in many different areas of modern medicine and is already an established standard in some disciplines like ear nose and throat (ENT) or maxillofacial surgery. When evaluating surgical navigation systems the absolute accuracy of the device is of major concern to the surgeon. The following work presents two different ways of measuring the accuracy of surgical...
An important function for a tactile navigation system of a handheld tool, such as a surgical scalpel, is the spatial transparency of the device. This paper proposed a new tactile display that can augment touch sensation at the finger pulps without the need for a stimulator between the tool and the finger pulps. We utilized transcutaneous electrical nerve stimulation at the middle phalanx of a finger...
Heart rate variability (HRV) may provide anesthesiologists with a noninvasive tool for monitoring nociception during general anesthesia. A novel wavelet transform cardiores-piratory coherence (WTCRC) algorithm has been developed to calculate estimates of the linear coupling between heart rate and respiration. WTCRC values range from 1 (high coherence, no nociception) to 0 (low coherence, strong nociception)...
We describe a method for performing modeling and simulation to predict the strain and stress experienced by tissues resulting from reconstructive cardiothoracic surgery. Stress computation is an important predictor of the quality and longevity of a repair and can therefore be used as guidance by a surgeon when deciding between various repair options. This paper uses the mitral valve repair as a use...
Monitoring the depth of anesthesia (DOA) is necessary in order to decrease the incident of awareness in anesthesia and to prevent delays in the recovery phase. In the last decades a number of noninvasive methods have been proposed for the analysis of the electroencephalogram (EEG) for monitoring DOA. The objective of this work was to apply auto mutual information function (AMIF) to EEGs of patients...
Laparoscopic partial nephrectomy has become more and more popular in the last decade. Video laparoscopes remain the gold standard of intraoperative imaging during laparoscopic interventions. However, providing only superficial images of the target tissue. In contrast, ultrasound (US) imaging may offer crucial information of the interior of the target tissue that could improve surgical outcome. In...
The effect on acid-base balance efficacy of intermittent warm and cold blood cardioplegia (IWBC, ICBC) was assessed in 44 patients who underwent cardiac surgery with prolonged aortic cross clamping. With this purpose a customized multi sensor probe was inserted in the coronary sinus, and pH, PO2, PCO2 and temperature were continuously measured at 1 Hz sampling rate. The mean cross-clamping time was...
Implanting microtechnologies into insects with an aim of domesticating its locomotion poses certain challenges, however, performing surgical implantation during the early stages of metamorphic growth was shown to mitigate some of the related detriments. This study reports the bioelectrical enhancement at the tissue-electrode interface allowed with these metamorphic stage insertions, where the electrodes...
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