Focal Spot, Spring 2007

https://digitalcommons.wustl.edu/focal_spot_archives/1105/thumbnail.jp

Role Of Active Surveillance And Volume Monitoring In Patients With Small Renal Masses

Introduction: Current standard treatment of small renal masses (SRM) is surgical resection, but it is not plausible in all patients. Since the behaviors of SRM are not completely understood, the management of such lesions remains controversial. We evaluated the rates of linear and volumetric growth and metastasis of solid SRM in patients followed by active surveillance (AS). Materials and Methods: We performed a retrospective medical records review of 38 patients followed by AS for solid SRM. We reviewed radiographic imaging and hospital records. Extracted variables included size of lesions at diagnosis and surveillance, duration of surveillance, available pathology and progression to metastasis. Results: Of the original 44 lesions, 36 lesions in 32 patients were included. Mean lesion size at initial presentation was 1.73cm. Mean duration of surveillance was 34.3 months. Benign and malignant lesions demonstrated mean linear growth rates of 0.19cm/yr vs. 0.31cm/yr and volumetric growth rates of 0.95cm3/yr vs. 2.91cm3/yr, respectively. Seven patients crossed over to surgery due to patient preference or significant interval lesion growth. Pathology was obtained in 25% of lesions, of which 44% proved to be malignant renal tumors known as renal cell carcinoma (RCC). There was no correlation between initial lesion size and growth rate. Progression to metastasis was not seen in any of the subjects. Neither of two deaths during surveillance was due to renal cancer. Conclusions: Most enhancing SRM grow slowly, making active surveillance a safe alternative to surgery in nonsurgical candidates. Changes in lesion volume may be a better predictor of cancer cell growth than linear growth

Development of a cognitive robotic system for simple surgical tasks

The introduction of robotic surgery within the operating rooms has significantly improved the quality of many surgical procedures. Recently, the research on medical robotic systems focused on increasing the level of autonomy in order to give them the possibility to carry out simple surgical actions autonomously. This paper reports on the development of technologies for introducing automation within the surgical workflow. The results have been obtained during the ongoing FP7 European funded project Intelligent Surgical Robotics (I-SUR). The main goal of the project is to demonstrate that autonomous robotic surgical systems can carry out simple surgical tasks effectively and without major intervention by surgeons. To fulfil this goal, we have developed innovative solutions (both in terms of technologies and algorithms) for the following aspects: fabrication of soft organ models starting from CT images, surgical planning and execution of movement of robot arms in contact with a deformable environment, designing a surgical interface minimizing the cognitive load of the surgeon supervising the actions, intra-operative sensing and reasoning to detect normal transitions and unexpected events. All these technologies have been integrated using a component-based software architecture to control a novel robot designed to perform the surgical actions under study. In this work we provide an overview of our system and report on preliminary results of the automatic execution of needle insertion for the cryoablation of kidney tumours

Hybrid Simulation and Planning Platform for Cryosurgery with Microsoft HoloLens

Cryosurgery is a technique of growing popularity involving tissue ablation under controlled freezing. Technological advancement of devices along with surgical technique improvements have turned cryosurgery from an experimental to an established option for treating several diseases. However, cryosurgery is still limited by inaccurate planning based primarily on 2D visualization of the patient's preoperative images. Several works have been aimed at modelling cryoablation through heat transfer simulations; however, most software applications do not meet some key requirements for clinical routine use, such as high computational speed and user-friendliness. This work aims to develop an intuitive platform for anatomical understanding and pre-operative planning by integrating the information content of radiological images and cryoprobe specifications either in a 3D virtual environment (desktop application) or in a hybrid simulator, which exploits the potential of the 3D printing and augmented reality functionalities of Microsoft HoloLens. The proposed platform was preliminarily validated for the retrospective planning/simulation of two surgical cases. Results suggest that the platform is easy and quick to learn and could be used in clinical practice to improve anatomical understanding, to make surgical planning easier than the traditional method, and to strengthen the memorization of surgical planning

Ablation of the locally advanced pancreatic cancer: An introduction and brief summary of techniques

Pancreatic ductal adenocarcinoma is a lethal and late presenting malignancy with dismal survival rates. An estimated total of 330,000 people died from this malignancy in 2012. Although there have been improvements in diagnostic and treatment methods, the survival of late stage pancreatic cancer has not shown significant improvement in the past 4 decades. Multiple treatment approaches are available including chemotherapy, radiotherapy, and immunotherapy, but to this day surgical resection remains the only curative treatment option. Ablative techniques use various forms of energy to cause local tissue destruction through necrosis or apoptosis. They are relevant in pancreatic ductal adenocarcinoma as they are a treatment option in non-resectable tumors where their use ranges from symptom control to reducing tumor size for resection. In this narrative review we have grouped and outlined the various ablative methods, classifying them into thermal (Radiofrequency ablation, Microwave ablation, High Intensity Focused Ultrasound ablation, Cryoablation), and non-thermal ablative methods (Irreversible Electroporation (NanoKnife®), Photodynamic Therapy). This is followed by a description and review of the available evidence on survival and complications for each of these ablative methods. According to the literature, thermal ablative methods appear to be more accessible but are implicated with more complications than non thermal ablative methods which show the most promise

The Realm of Oncological Lung Surgery: From Past to Present and Future Perspectives

In this chapter, a historical overview as well as an overview of state of the art of the surgical techniques for the treatment of lung cancer is outlined. The chapter focuses on the introduction of open surgery, video-assisted thoracic surgery (VATS), uniportal VATS (UVATS), and robotic-assisted thoracic surgery (RATS) techniques for lung resections. A short introduction on upcoming techniques and modalities is given. The currently available tools as three-dimensional (3D) computed tomography (CT), virtual reality, and endo-bronchial surgery will be discussed. Based on the current development, this chapter attempts to delineate the horizon of oncological lung surgery. The information is generated not only from the available literature, but also from the experiences of surgeons and other physicians as well as co-workers involved in lung cancer treatment around the world. This chapter can be seen as a general introduction to several aspects of oncological lung surgery

Improvement of design of a surgical interface using an eye tracking device

Surgical interfaces are used for helping surgeons in interpretation and quantification of the patient information, and for the presentation of an integrated workflow where all available data are combined to enable optimal treatments. Human factors research provides a systematic approach to design user interfaces with safety, accuracy, satisfaction and comfort. One of the human factors research called user-centered design approach is used to develop a surgical interface for kidney tumor cryoablation. An eye tracking device is used to obtain the best configuration of the developed surgical interface. Surgical interface for kidney tumor cryoablation has been developed considering the four phases of user-centered design approach, which are analysis, design, implementation and deployment. Possible configurations of the surgical interface, which comprise various combinations of menu-based command controls, visual display of multi-modal medical images, 2D and 3D models of the surgical environment, graphical or tabulated information, visual alerts, etc., has been developed. Experiments of a simulated cryoablation of a tumor task have been performed with surgeons to evaluate the proposed surgical interface. Fixation durations and number of fixations at informative regions of the surgical interface have been analyzed, and these data are used to modify the surgical interface. Eye movement data has shown that participants concentrated their attention on informative regions more when the number of displayed Computer Tomography (CT) images has been reduced. Additionally, the time required to complete the kidney tumor cryoablation task by the participants had been decreased with the reduced number of CT images. Furthermore, the fixation durations obtained after the revision of the surgical interface are very close to what is observed in visual search and natural scene perception studies suggesting more efficient and comfortable interaction with the surgical interface. The National Aeronautics and Space Administration Task Load Index (NASA-TLX) and Short Post-Assessment Situational Awareness (SPASA) questionnaire results have shown that overall mental workload of surgeons related with surgical interface has been low as it has been aimed, and overall situational awareness scores of surgeons have been considerably high. This preliminary study highlights the improvement of a developed surgical interface using eye tracking technology to obtain the best SI configuration. The results presented here reveal that visual surgical interface design prepared according to eye movement characteristics may lead to improved usability.European Commissionpublisher versio

More Than Just Tumor Destruction: Immunomodulation by Thermal Ablation of Cancer

Over the past decades, thermoablative techniques for the therapy of localized tumors have gained importance in the treatment of patients not eligible for surgical resection. Anecdotal reports have described spontaneous distant tumor regression after thermal ablation, indicating a possible involvement of the immune system, hence an induction of antitumor immunity after thermoinduced therapy. In recent years, a growing body of evidence for modulation of both adaptive and innate immunity, as well as for the induction of danger signals through thermoablation, has emerged. Induced immune responses, however, are mostly weak and not sufficient for the complete eradication of established tumors or durable prevention of disease progression, and combination therapies with immunomodulating drugs are being evaluated with promising results. This article aims to summarize published findings on immune modulation through radiofrequency ablation, cryoablation, microwave ablation therapy, high-intensity focused ultrasound, and laser-induced thermotherapy