Andres Castellanos

Robotic surgery: a current perspective.

Objective:To review the history, development, and current applications of robotics in surgery. Background:Surgical robotics is a new technology that holds significant promise. Robotic surgery is often heralded as the new revolution, and it is one of the most talked about subjects in surgery today. Up to this point in time, however, the drive to develop and obtain robotic devices has been largely driven by the market. There is no doubt that they will become an important tool in the surgical armamentarium, but the extent of their use is still evolving. Methods:A review of the literature was undertaken using Medline. Articles describing the history and development of surgical robots were identified as were articles reporting data on applications. Results:Several centers are currently using surgical robots and publishing data. Most of these early studies report that robotic surgery is feasible. There is, however, a paucity of data regarding costs and benefits of robotics versus conventional techniques. Conclusions:Robotic surgery is still in its infancy and its niche has not yet been well defined. Its current practical uses are mostly confined to smaller surgical procedures.

Force Feedback Plays a Significant Role in Minimally Invasive Surgery Results and Analysis

Objective:To evaluate the role of force feedback with applications to minimally invasive surgery (MIS). Two research hypotheses were tested using our automated laparoscopic grasper. Summary Background Data:Conventional laparoscopic tools do not have the ability of providing force feedback to a surgeon when in use with or without robotic surgical systems. Loss of haptic (force and tactile) feedback in MIS procedures is a disadvantage to surgeons since they are conventionally used to palpating tissues to diagnose tissues as normal or abnormal. Therefore, the need exists to incorporate force feedback into laparoscopic tools. Methods:We have developed an automated laparoscopic grasper with force feedback capability to help surgeons differentiate tissue stiffness through a haptic interface device. We tested our system with 20 human subjects (10 surgeons and 10 nonsurgeons) using our grasper to evaluate the role of force feedback to characterize tissues and answer 2 research hypotheses. Results:Our experiments confirmed 1 of our 2 research hypotheses, namely, providing both vision and force feedback leads to better tissue characterization than only vision feedback or only force feedback. Conclusions:We have validated 1 of our 2 research hypotheses regarding incorporating force feedback with vision feedback to characterize tissues of varying stiffness.

Real-Time Haptic Feedback in Laparoscopic Tools for Use in Gastro-Intestinal Surgery

One of the limitations of current surgical robots used in surgery is the lack of haptic feedback. While current surgical robots improve surgeon dexterity, decrease tremor, and improve visualization, they lack the necessary fidelity to help a surgeon characterize tissue properties for improving diagnostic capabilities. Our work focuses on the development of tools and software that will allow haptic feedback to be integrated in a robot-assisted gastrointestinal surgical procedure. In this paper, we have developed several tissue samples in our laboratory with varying hardness to replicate real-tissues palpated by a surgeon in gastrointestinal procedures. Using this tissue, we have developed a novel setup whereby the tactile feedback from the laparoscopic tool is displayed on the PHANToM haptic interface device in real-time. This is used for tissue characterization and classification. Several experiments were performed with different users and they were asked to identify the tissues. The results demonstrate the feasibility of our approach.

Surgical management of chronic lower abdominal and groin pain in high-performance athletes.

Formerly, most of the causes and treatments of chronic lower abdominal and groin pain in high-performance athletes eluded sports medicine specialists. Now we are much better at identifying and managing the different syndromes. Most of the advances are based on empiric evidence, although many pitfalls remain with respect to diagnosis and management of the various syndromes. This article reviews our current understanding of several of these clinical entities. We focus on lessons learned from a large 15-year experience.

Optimizing single port surgery: a case report and review of technique in colon resection.

Minimally invasive colon surgery was first described in the early 1990s, decreasing the morbidity compared with open procedures. Recently, single port laparoscopy has emerged, with reports of applications to colon surgery. Although feasible, many new technical challenges exist.

Robotic Resection of Pheochromocytoma in the Second Trimester of Pregnancy

In this study, a Da Vinci robotic system was successfully used to perform resection of pheochromocytoma during the second trimester of pregnancy.

Evaluating the Role of Vision and Force Feedback in Minimally Invasive Surgery: New Automated Laparoscopic Grasper and A Case Study

Conventional laparoscopic tools do not have the ability of providing force feedback to a surgeon during surgical procedures. Loss of haptic feedback in MIS procedures is a disadvantage to surgeons since they are conventionally used to palpating tissues to diagnose whether the tissue is normal or abnormal. Therefore, a need exists to incorporate force feedback into laparoscopic tools. We have developed a laparoscopic grasper with force feedback capability to help surgeons characterize tissues. Through our interface, the surgeon can feel the tissue grasping forces while interacting with the PHANToM (haptic interface device). Our laparoscopic tool has a modular design for easy conversion between a grasper, cutter, and dissector. We have done several experiments to test two hypotheses with human subjects (20 subjects; 10 surgeons and 10 non-surgeons) to characterize tissues of varying hardness using only vision, only force, and simultaneous vision and force feedback.

Brain-in-the-Loop Learning Using fNIR and Simulated Virtual Reality Surgical Tasks: Hemodynamic and Behavioral Effects

Functional near infrared spectroscopy (fNIR) is a noninvasive, portable optical imaging tool to monitor changes in hemodynamic responses (i.e., oxygenated hemoglobin (HbO)) within the prefrontal cortex (PFC) in response to sensory, motor or cognitive activation. We used fNIR for monitoring PFC activation during learning of simulated laparoscopic surgical tasks throughout 4 days of training and testing. Blocked (BLK) and random (RND) practice orders were used to test the practice schedule effect on behavioral, hemodynamic responses and relative neural efficiency (EFFrel-neural) measures during transfer. Left and right PFC for both tasks showed significant differences with RND using less HbO than BLK. Cognitive workload showed RND exhibiting high EFFrel-neural across the PFC for the coordination task while the more difficult cholecystectomy task showed EFFrel-neural differences only in the left PFC. Use of brain activation, behavioral and EFFrel-neural measures can provide a more accurate depiction of the generalization or transfer of learning.

Modeling In vivo Soft Tissue Probing

A biomechanical model of in vivo soft tissue derived from experimental measurements is critical for developing a reality-based model for minimally invasive surgical training and simulation. In our research, we have been focusing on developing a biomechanical model of the liver with the ultimate goal of using this model for local tool-tissue interaction tasks and providing feedback to the surgeon through a haptic (sense of touch) display. In this paper, we present our approach for characterizing the nonlinear property of soft tissue in vivo under large deformation. We developed an experimental method for in vivo soft tissue test, and an axisymmetric finite element model to obtain the local effective elastic modulus (LEEM) of the tissue. A microcontroller-based portable probe was developed to measure the force and displacement in vivo of the pig liver tissue undergoing large deformation. The probe indented the liver up to 40% of its nominal thickness at a speed of 1.5 mm/sec. Based on the experimental force and displacement data, we obtained the LEEM by an inverse finite element method

Single‐incision laparoscopic cholecystectomy

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