2010 至 2020 年医疗机器人研究十年回顾

Just more than three decades ago, the first roboticists began to explore the use of robot manipulators for performing surgical procedures. Two decades ago, the first commercial systems were installed in hospitals. In the past decade, the field of medical robotics has gained momentum, and thousands of robotic surgical systems are now installed in clinics around the world, and many millions of procedures have been performed. As the acceptance of surgical robots by our health care systems has become clear, robotics researchers have increasingly focused their attention on what the next generation of medical robots might look like. Their attention is not limited to surgical robots, and other areas of medicine are also being investigated, including robots to perform physical rehabilitation, telepresence robots for patient interaction with off-site health care workers, pharmacy automation, robots for disinfecting clinics, and more.
三十多年前，第一批机器人专家开始探索使用机器人机械手进行外科手术。二十年前，医院安装了第一批商用系统。在过去的十年中，医疗机器人技术领域的发展势头迅猛，目前世界各地的诊所已安装了数千台机器人手术系统，并已实施了数百万例手术。随着医疗系统对手术机器人的认可，机器人研究人员越来越关注下一代医疗机器人的发展。他们的关注点并不局限于手术机器人，其他医疗领域的机器人也在研究之中，包括进行身体康复的机器人、用于病人与异地医护人员互动的远程呈现机器人、药房自动化、用于诊所消毒的机器人等等。

Medical robots were first developed to allow surgeons to operate remotely and/or with improved precision on their patients, and the history of the field is well documented in the literature (1–3). The earliest efforts can be traced back to applications in neurosurgery (4) and orthopedic surgery (5). The first truly long-distance telesurgery was a transatlantic cholecystectomy performed 20 years ago (6). Although early progress in the field was somewhat unsteady, as is to be expected with the introduction of any radically new technology, medical robotics has reached a level of maturity that has encouraged the health care industry to make substantial investments in development activities.
开发医用机器人的初衷是为了让外科医生能够远程操作病人和/或提高操作精度，该领域的历史在文献中有详细记载（1-3）。最早的应用可追溯到神经外科（4）和整形外科（5）。第一次真正意义上的远距离远程手术是 20 年前进行的跨大西洋胆囊切除术（6）。虽然该领域的早期进展有些不稳定，但正如任何全新技术的引入所预料的那样，医疗机器人技术已经达到了一定的成熟度，从而鼓励医疗保健行业对开发活动进行大量投资。

Researchers, however, generally look farther into the future and beyond commercial development activities. As we consider some of the key research activities in the past decade, we obtain a glimpse of where medical robotics will head in the coming decades. This article focuses on the past 10 years and provides a retrospective assessment of the major accomplishments in medical robotics. We use an inclusive definition for what constitutes a medical robot that is intended to cover all material that would be appropriate for inclusion in a major robotics research journal or conference. This encompasses single- and multi–degree-of-freedom (DOF) motorized systems with motions that may be preprogrammed, joystick-prescribed, autonomous, or some combination of the three. We define medical robotics research as the creation of new robots and robotic technologies for medical interventions. A large body of medical journal papers devoted to the evaluation of existing medical robots has also been published over the past decade. Because these robots largely represent technologies developed during prior decades, they are not discussed here. Here, our goal was to identify the major research themes or “hot topics” in medical robotics over the decade and to summarize the seminal research papers that concisely highlight these themes.
不过，研究人员通常会把目光投向更长远的未来，而不是商业开发活动。当我们回顾过去十年中的一些重要研究活动时，就能窥见医疗机器人技术在未来几十年中的发展方向。本文聚焦过去十年，对医疗机器人领域的主要成就进行回顾性评估。对于什么是医疗机器人，我们采用了一个包容性的定义，旨在涵盖所有适合纳入主要机器人研究期刊或会议的材料。这包括单自由度和多自由度（DOF）机动系统，其运动方式可以是预编程、操纵杆规定、自主或三者的某种组合。我们将医疗机器人研究定义为为医疗干预创造新的机器人和机器人技术。过去十年间，医学期刊上也发表了大量专门评估现有医疗机器人的论文。由于这些机器人主要代表的是前几十年开发的技术，因此在此不做讨论。在此，我们的目标是确定这十年来医疗机器人领域的主要研究主题或 "热点话题"，并总结能够简明扼要地突出这些主题的开创性研究论文。

The number of papers on medical robotics has grown exponentially from less than 10 published in 1990 to more than 5200 in 2020. Consequently, the fraction of papers published during the past decade is more than 80% of the total. These publications span the entire range of the research pipeline. Engineering journal publications have covered the creation of new robotic technologies for medical applications and the design of new medical robots. Medical journal publications have completed the research process by evaluating existing robot designs in human patients.

Although the field cannot yet point to comprehensive clinical trials that show that robotic surgical procedures provide improved procedural outcomes for patients (70) or reduced procedure cost compared with nonrobotic surgery (71), a number of patient benefits have been demonstrated. These include shorter hospital stays, faster recuperation, fewer reoperations, and reduced blood transfusions (71). For surgeons, robots provide improved ergonomics, leading to reductions in neck and back pain (72) as well as hand and wrist numbness (73) with less physical and mental stress compared with direct hand-controlled procedures (74). These factors increase a surgeon’s quality of life and could potentially lengthen their career. Studies have also shown that robotics can markedly reduce radiation exposure to both the surgeon and the patient (75).

To further this progress, it would be beneficial to channel future engineering research efforts in the most promising directions. This requires developing an understanding of how robots and their underlying technologies add value in medicine. Whereas in almost all other industries, robots are used as autonomous agents to reduce human labor costs, medical robots, at least to date, have been developed to add value in other application-dependent ways.

For example, all the benefits mentioned in the preceding paragraph arise in laparoscopic surgery except for reduced radiation exposure, which applies to cardiac catheterization procedures. In therapeutic rehabilitation, it can be argued that the value currently added is in providing a larger number of repetitions rather than in improving the quality of the repetitions. On the other hand, energy-delivery robots, e.g., for radiotherapy, provide a combination of precision, repeatability, and speed that is hard to match by other means. Similarly, a powered prosthesis can directly improve patient outcomes by expanding both the number and quality of daily living tasks that can be performed compared with a nonrobotic device. Capsule robots may eventually replace some open bowel procedures, improving the diagnostic possibilities in hard-to-reach body regions and reducing the discomfort of existing endoluminal bowel procedures.

In directing robotic technology research to maximize value added, the most important technology targets are those that will enable new types of interventions that are either currently impossible or impractical based on current technology. Magnetic actuation is an example of a technology that is enabling for capsule robots and medical microrobots. This technique has allowed miniaturization by moving actuation and power supplies outside the body. Soft robotics is likely to be a very important enabling technology over the next decade. Much of the most promising work is currently being performed in the materials community and relates to the creation of thin polymer layers with embedded sensors and actuators. Although this work seems far from medical application now, these capabilities will likely have a large influence on interventional, rehabilitative, and assistive robots. Other enabling technologies in sensing, imaging, actuation, and energy storage may arise as crossovers from consumer electronics.

As an alternative to enabling new procedures, a technology can have a major influence if it provides a new way for a medical robot to add value. The effective synergy of preoperative and intraoperative imaging integrated with flexible, ergonomically enhanced surgical tools is an important example of this approach, which represents a substantial contribution over the past decade. The value of this approach will likely continue in the future. Translating cellular and molecular imaging modalities from the laboratory to an in vivo–in situ surgical setting will further expand the functional capabilities of surgical interventions by providing improved tissue detection, labeling, and targeting for both macroscopic and cell-based therapies. This approach can fundamentally alter the planned surgical pathways by streamlining intraoperative surgical decision making and optimization with increased consistency and accuracy, circumventing potential postoperative complications and revisions.

Another way for robots to add value is through autonomy. Although the development of autonomous driving capabilities has been perhaps the hottest topic in all of robotics over the decade, the use of autonomy in medical robots is currently limited. Examples include assistive wearable robots and rehabilitation robots. These systems produce preprogrammed motions that can be switched between and altered on the basis of user inputs. Similarly, orthopedic robots mill out preprogrammed cavities in bone, and radiosurgery robots play back preprogrammed trajectories to produce the desired x-ray exposures of internal lesions. Although these preprogrammed motions represent a very simple form of autonomy, they are enabling for these applications. For example, an assistive lower leg prosthesis would be useless if the operator had to actively control the ankle motion during walking.

The technological frontier in medical robot autonomy corresponds to endowing the robot with the capability to formulate and alter its plans and motions based on real-time sensor data. Examples could include autonomous laparoscopic surgery to remove cancerous lesions or autonomous transcatheter repair of a heart valve. This level of autonomy brings with it not only technical challenges but also regulatory, ethical, and legal challenges, which have yet to be fully resolved and will raise commercialization costs. Consequently, it will be much easier to incrementally add such autonomous functionality to preexisting medical robots whose value can be justified without consideration of autonomous functionality. Examples include automated suturing for laparoscopic surgery, autonomous navigation of flexible endoscopes, or autonomous electrophysiological catheter mapping inside the heart.

An evolutionary trend toward progressive automation as suggested by Fig. 4 will provide time for the necessary technological developments in algorithms and sensors while allowing stakeholders time to progressively construct an appropriate regulatory and legal framework. Medical applications for which autonomy is necessary to justify the robot will be more challenging to commercialize in the short term but may be of highest value in the long term. The lower hanging fruit of this type could include simple time-critical endoluminal interventions, whereas bionic implants represent a more complicated class of devices.

Of the more than 19,000 engineering papers published on medical robotics since 1990, only a handful can be considered enabling for existing commercial medical robots. Even the papers of high technological influence comprising the bibliography have modest numbers of patent citations. In part, this may be due to the substantial lag that can occur between technology development and its commercial application. Perhaps, an equally important contributor is the mismatch between technology research and the realities of medical device commercialization.

Bringing robotic technology to clinical use requires much more than simply well-cited research articles. A genuine clinical need must be identified. A relevant technology must be developed to address this need that considers the specifics of how the robot adds value for the clinician and for the patient. Medical doctors must be convinced of this value proposition. The technology must also be developed with hospital administrative and financial constraints well considered and without hindering well-established clinical workflows. Potential risks must be identified early on so that ethical approvals can be obtained. Last, attractive business models must be developed to ensure that sufficient investment can be obtained to bring the technology through the complex pathways that must be navigated for any medical device to achieve commercial success. Maximizing the chance of success suggests that technology researchers stray from their ivory towers to form deep collaborations with clinicians, regulators, investors, and the business community.

The manuscript is not intended to be a traditional survey that provides sweeping coverage of medical robotics over the decade or to provide an exhaustive bibliography of the field. Instead, our goal was to provide a focused view of the most important research advances of the decade and to point the reader to a small set of papers that are seminal with respect to these advances. Research was defined as the development of new robots and robotic technology. Clinical evaluation papers using existing robots were excluded unless they conveyed an important translational result.

This approach, by its nature, injects some subjectivity into the paper; however, we attempted to be as objective as possible. Our approach was as follows. We first developed an initial list of prospective hot topics based on author consensus. This list of topics was then validated and refined by performing a broad search of medical/surgical robotics using Web of Science and then grouping the results by topic. This resulted in dropping some candidate topics while subdividing others into multiple topics. For example, although there has been important work in orthopedic and spinal procedure robots, the highly cited papers were published before 2010. Furthermore, we observed that there was important research on procedure-specific robots that did not fit into any of the hot topics. This included robots developed for endoluminal and natural orifice transluminal endoscopic surgery procedures along with robots for microsurgery. To include this work, we added a final hot topic on nonlaparoscopic procedure–specific robots.

Given this list of hot topics, we then sought to identify topic-specific search terms for use with Web of Science that would provide comprehensive coverage for that topic. Our goal was twofold. First, we wished to identify the total number of papers published on each hot topic as reported in Figs. 2 and 3. Second, for inclusion in our bibliography, we wished to identify the most influential papers for each topic based on citation count.

Identification of the topic-specific search terms meeting these two goals was an iterative process. Initially, each search was formulated by building a set of common terms related to medical robots that returned the most comprehensive set of relevant references:

This search was then further constrained using keywords for each hot topic. The keywords were tested and revised by reviewing the search results based on the authors’ knowledge of the field to ensure that the results for the top 100 cited papers returned by the search were both relevant and comprehensive. This approach worked well for four of the eight topics. For the remaining four topics, it was also necessary to adapt the common search terms along with topic-specific keywords to identify a search that yielded relevant and comprehensive results.

Each section of the paper was then composed on the basis of the authors’ knowledge of the topic as supported by the search results. For each hot topic, a small number of the most highly cited research papers were selected to support the major concepts. These are the papers included in the bibliography. Although, in some cases, papers had similar numbers of citations and subjective decisions were made to pick one over another, the overall selection process was objective. Survey papers were excluded.

Paper citation counts included in the bibliography of the Supplementary Materials are from Web of Science. Patent citation counts are from Lens.org. Data were collected on 11 October 2021.

We thank M. Mencattelli for assistance with the figures and references. We also thank Y. Guo and Z. Zhang for preparing Figs. 1 and 4.

Funding: Partial support for P.E.D. was provided by the NIH under grants R01NS099207 and R01HL124020. Partial support for B.J.N. was provided by the Swiss National Science Foundation through grant 200020B_185039 and by the ERC through advanced grant 743217. Partial support for M.K.O. was provided by the National Science Foundation under grant 2025130 and by the TIRR Foundation under grant 018-114. Partial support for G.-Z.Y. was provided by the Science and Technology Commission of Shanghai Municipality under grant 20DZ2220400.

Author contributions: All authors assisted in writing and editing the paper.

Competing interests: N.S. is an inventor on patent US 8116886 B2 submitted by Columbia University that covers works on steerable continuum/soft robots as implants (licensed to Auris Surgical); an inventor of US 9089354 B2 and US 10058390 B2 submitted by Johns Hopkins University on continuum robots for confined spaces and upper airway surgery and on U.S. patent 10406026 on steerable continuum robots for intraocular surgery (licensed to Intuitive Surgical and Carl Zeiss GmbH); and an inventor on U.S. patent application US 2014/0350337 A1 submitted by Columbia University on continuum robots for single port access and commercially translated through a research agreement to Titan Medical. B.H. is a cofounder of Applied Dexterity Inc. The other authors declare that they have no relevant competing interests.

Data and materials availability: All data presented in the paper can be reproduced as described in Materials and Methods.