Application of robotic systems in neurosurgery: problems and prospects

Khasan A. Magamaev, Khuseyn A. Magamaev, Kristina D. Deminskaya, Kamila K. Kadieva, Islam R. Guseinov, Anna S. Zolotar, Anastasia P. Malevanets, Ekaterina E. Meteleva, Magomed-saygid M. Magomedov, Ekaterina A. Alekseeva. Application of robotic systems in neurosurgery: problems and prospects. Cardiometry; Issue 31; May 2024; p. 132-137; DOI: 10.18137/car-diometry.2024.31.132137; Available from:

Medical robotics has advanced significantly since its inception. Modern robotic systems available for surgery can be divided into three main categories: active, semi-active and “master-subordinate”[1]. Active systems work autonomously and perform pre-programmed tasks, whereas the “master-subordinate” systems do not have pre-programming and are completely dependent on the input of the surgeon. Semi-active systems are a hybrid in which the surgeon’s contribution complements the pre-programmed elements of the system.

Neurosurgery, as one of the most complex and technologically intensive fields of medicine, is constantly striving to improve treatment outcomes and reduce risks for patients. In recent decades, robotic systems have begun to play an increasingly important role in neurosurgical practice, opening up new horizons of possibilities for surgeons and patients. These systems offer the potential to improve surgical precision, expand access to hard-to-reach areas of the brain, and reduce the risks of surgery.

Robotic systems provide surgeons with improved visualization, greater accuracy and reduced fatigue. However, there are problems related to equipment maintenance, cost, and sterilization. they impose some restrictions on the implementation of such systems.

Although the first case of robotic surgery occurred in neurosurgery, robotics is now more common in areas with relatively fewer anatomical space constraints, such as urology, gynecology, and orthopedics. In general, robotic assistance in neurosurgery can be especially useful for procedures with very limited operating space: for example, certain areas of application of robots in neurosurgery include anatomical localization, stabilization of the surgeon’s hand, anatomical planning of access to deep brain objects and the installation of transpedicular screws during spinal surgery.

The purpose of the work is to consider the features of the use of robotic systems in neurosurgery, as well as emerging problems and prospects in this area.

MATERIALS AND METHODS

In the process of writing the work, an array of articles and monographs were analyzed within the framework of the research topic. These materials included the characteristics of various neurosurgical procedures and techniques used in surgical practice, as well as the study of the principles of operation of robotic systems, their design, technical characteristics and basic functions. Also, the studies reviewed concerned the study of specific applications of robots in the medical field, such as surgery, rehabilitation, diagnostics, etc. As noted in the literature, neurosurgery occupies a special place in this field because of its complexity and demanding nature. In addition, in the process of writing the work, the process of introducing robotic systems into medical practice was studied, including technical and organizational aspects, personnel training requirements, as well as ensuring compatibility with existing systems and procedures, as well as methods for evaluating the effectiveness of robotic systems in neurosurgery, including clinical trials, analysis of results and comparison with traditional methods. In the process of writing the work, comparative and analytical research methods were used.

RESULTS

Microsurgery is a surgical procedure involving surgery on small structures using a surgical microscope or other instrument that allows magnification of the image[2]. Visual magnification allows surgeons to operate with greater precision and accuracy, which increases the effectiveness of treatment. Due to its unique advantages, microsurgery has become widespread in various surgical specialties, including ophthalmology, otolaryngology, neurosurgery, reconstructive surgery and urology, where complex and precise manipulation of a surgical instrument on a small scale is required.

Microsurgery is implemented in limited sensory conditions, which requires highly precise surgical skills and extensive training from the surgeon. In this regard, to increase the effectiveness of caviar surgery, an increasing number of researchers have begun to explore the possibilities of using robotic technologies in microsurgery and have developed various robotic microsurgical systems (MSS) [3]. MSS can enable surgeons to provide increased accuracy and stability through features such as tremor filtering and motion scaling. By integrating various perception and feedback technologies, MSS can provide more complete information about the surgical environment and offer intuitive intraoperative guidance. These systems can also increase the comfort of surgeons during surgical operations due to their ergonomic design.

Three classifications of robotic surgery systems have been described by specialists based on the interaction of the robot and the surgeon. The robotic system with dispatch control is the first classification. In this system, the robotic surgery procedure is programmed and then monitored by the surgeon during the intervention while the robot performs the programmed movements.

Robotic tele–surgery is the second system that is controlled and programmed by the surgeon in real time via remote access. Robotic surgery with joint control is the third of these systems. Here, the surgeon controls the robot’s movements and interventions, as the robot improves the surgeon’s skills by improving dexterity, as well as some mechanical solutions that take into account human limitations [4].

Several robotic methods have been expanded to solve specific tasks related to brain surgery. Combining robotic surgical systems with various imaging devices can improve the accuracy of surgical procedures and provide some benefits by improving feedback from the surgeon.

One of the simplest and most applicable robots with supervisory control is a special type of radiosurgi-cal system “Lexell Gamma knife”. The automated system precisely adjusts the position of the patient’s head based on the geometric parameters of the calculated radiation therapy plan. Several studies have reported on the advantages and benefits of the Gamma Knife robotic automatic system, such as shorter setup time, lower radiation doses to patients and staff, and higher accuracy of radiation delivery to smaller targets [5].

The NeuroMate system (Integrated Surgical Systems, Sacramento, California, USA) was the first robotic system for neurosurgery. This robotic device uses a robotic arm that can move in various pre-programmed directions under the control of a navigation system for neurosurgical applications and stereotactic biopsy procedures [6].

Another robotic surgical device was the Evolution 1 robotic system (Universal Robot Systems, Schwerin,

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Germany), which was successfully tested in various neurological operations such as endoscopic resection of pituitary adenoma and installation of transpedicular screws. Another robotic surgical system called Neurobot telerobotic has been evaluated and successfully applied in complex neurosurgical procedures. Experts described the use of this system in craniotomy for resection of surface areas of the tumor [7].

The Da Vinci surgical system is the most common robotic surgical system for general and gynecological surgery. This system is also used for neurosurgical purposes due to its capabilities, including a system under visual control, a high degree of freedom of movement, minimally invasive surgery and a full range of movements simulating a human wrist. It has been reported that the use of the Da Vinci surgical system may have advantages over traditional surgical procedures, such as higher accuracy, minimal tissue injury, and shorter patient recovery time. However, it has also been reported that this system can increase the time of a surgical procedure and does not have higher accuracy in brain surgery compared to manual techniques [8].

Determining the location of the lesion is crucial for the removal of a brain tumor, which can be improved through the introduction of navigation systems using medical imaging technologies. In addition, the connection of sensory tumor detection systems, such as fluorescence sensors, with an accurate robotic arm will allow further development of tumor removal methods.

One group of specialists presented a touch-based robotic surgery workstation where a surgeon can view and use imaging data without interrupting the operation procedure. The workstation consists of hand-held controllers and can display a three-dimensional image of MR images, a virtual image of manipulators and a stereoscopic image of the operating field. Initially, this system was used to treat neoplasia of the central nervous system and cavernous angioma, which indicates a high accuracy of surgical actions [9].

Another group of specialists reported on the use of a robotic microneurosurgery system for deep brain surgery procedures. They pointed out that their system increased the dexterity and maneuverability of specialists in deep surgical fields [10].

An important point of using robotic systems in neurosurgery is that their precision and precision are combined with the executive capabilities of the human brain by controlling the robotic system on the part of 134 | Cardiometry | Issue 31. May 2024

the surgeon. The millimeter-accurate robot provides a viable solution to ensure high accuracy in minimally invasive brain surgery. In addition, the computer technology of a robotic surgical system with an imaging device can provide safer surgical directions and restricted surgical areas.; therefore, it can improve the safety and effectiveness of the surgical procedure.

There are several robotic systems designed to solve the problems of spinal surgery. These devices have been improved by increasing the efficiency of intraoperative image management systems [11]. In addition, intraoperative radiotherapy (radiosurgery) can be considered one of the most common methods of robotic spine surgery; however, this is not a real surgical method, and it can be used as an auxiliary or alternative method of surgical intervention. In radiosurgery, robotics can track the movements of the spine due to breathing and irradiate the target tissue with high accuracy.

Robotic surgery can be an accurate, safe and suitable technique for minimally invasive brain and spinal surgery. However, the biggest disadvantage of robotic operations is the lack of sensory feedback, such as damage recognition, as well as the position, speed, or acceleration of tools. This disadvantage may be more significant in complex surgical areas such as the brain, and this may be the reason for not using robotic brain surgery techniques. However, all sensory feedbacks, which are not limited to visual signals only, are under development, and in the future robotic surgery will take up a significant part of operations on the brain and spine.

DISCUSSION

Microsurgery involves manipulating micron-sized targets, including the treatment of delicate and fragile tissues, as well as suturing or injecting small vessels, nerves and lymphatic channels. These tasks require a high degree of accuracy, and unintentional shaking during manipulation of instruments by a surgeon can reduce the accuracy of the actions performed and harm the body [12].

The surgeon’s perception of the surgical environment in microsurgery is limited. The limited field of view and depth of field of a surgical microscope make it difficult to perceive information about the surgical field. Microsurgical procedures require surgeons to maintain a high level of concentration, and often long-term surgical tasks are performed in ergonom- ically unfavorable positions. This can lead to physical and mental fatigue, increasing the risk of unintended mistakes.

Due to the precision and complexity of microsur-gical tasks, surgeons require extensive professional training before performing clinical procedures. These problems hinder the optimal results of microsurgical procedures and their widespread implementation [13].

MSS has great potential to expand the field of microsurgery, which provides increased stability and safety, mitigating problems such as tremor and reducing the degree of interaction with affected tissues. In several studies on robotic vascular and lymphatic anastomosis and comparing the learning curves of manual surgery with robotic surgery, surgery using MSS took longer, but had greater microsurgical accuracy than traditional methods of anastomosis. However, it is worth noting that the learning curve of robotic surgery indicates a higher rate of reduction in surgery time with fewer trials, while both modes of operations require a comparable amount of time to complete the task at the final stage of training. Currently, researchers have studied the possibilities of using robotic technologies in microsurgery [14].

During a robotic operation, the surgeon can directly or remotely transmit control commands to the MSS, which, in turn, controls surgical instruments to interact with target tissues with increased accuracy and stability. At the same time, surgical information is collected by a microscope and other sensors in real time, and then transmitted to the surgeon in the form of visual feedback.

In some MSS systems, the robot can perceive the environment using various sensors, and information that can help improve the results of surgical intervention (for example, the strength of the interaction of the instrument with tissue, the depth of the tip of the instrument, danger zones, etc.) is transmitted back to the surgeon through the human-machine interface in various forms. Moreover, some MSS systems have achieved a certain level of autonomy based on an adequate perception of the environment, which allows the robot to perform certain tasks autonomously under the supervision of a surgeon.

Depending on the control method, MSS can be divided into portable, remote-controlled, jointly controlled and partially automated robots. All of them use a microscope and/or OCT as visual feedback [15].

In a portable robotic system, the surgical instrument itself is transformed into a miniature robotic sys- tem called a robotic instrument. The surgeon manipulates it to perform a surgical procedure. The robotic tool provides tremor elimination, depth fixation and other functions.

In a remote-controlled robotic system, the surgeon manipulates the main module to control the slave module, which replaces the surgeon’s hand to control the surgical instrument. The system combines the functions of motion scaling and tremor filtering using servo rhythms. In addition, it provides three-dimensional perception by integrating tactile feedback or depth perception algorithms at the end of a surgical instrument.

In a co-controlled robotic system, the surgeon manipulates the surgical instrument at the same time as the robot. While the surgeon manually manipulates the surgical instrument, the robot also holds the surgical instrument, which provides auxiliary compensation for hand tremor and allows for prolonged immobilization of the surgical instrument [16].

In a partially automated robotic system, certain procedures or steps of procedures are performed automatically by the robot. The robot directly manipulates and controls the movement of the surgical instrument. Information about the processed image is transmitted to the robot as feedback and instructions. At the same time, visual information is transmitted to the surgeon, who can at any time order the cancellation of control over the partially automated procedure.

Visualization technologies play a crucial role in MSS systems. In traditional microsurgery, surgeons rely primarily on an operating microscope to observe the surgical environment, which helps surgeons to clearly observe the tissue and perform accurate surgery by increasing the surgical field. As technology continues to evolve, MSS systems are using more and more imaging techniques to provide additional information about the surgical environment. These imaging techniques can help surgeons better identify the target tissue or guide the robot’s intraoperative movements to achieve better surgical results [17]. Currently, a number of MRI-controlled robotic systems have been developed for stereotactic or percutaneous intervention. In the field of microsurgery, an MRI-compat-ible MSS system has been developed for neurosurgery. The robotic arm is made of non-magnetic materials such as titanium and polyesterephyrketone to prevent magnetic fields or gradients from affecting its performance and to ensure that the robot does not degrade the essential image quality. The system allows you to align the position of the robot arm with intraoperative MRI scans, allowing you to perform stereotaxy in the imaging environment (magnet hole) and microsurgery outside the magnet.

Optical coherence tomography (OCT) is a non–in-vasive imaging technique that uses low-coherence light to create 2D and 3D images in light-scattering media. It is capable of capturing high-resolution images (520 microns) in real time, as well as visualizing surgical instruments and subsurface anatomy, and has been widely used in ophthalmology. Many researchers have integrated OCT technology with MSS to provide intraoperative guidance in various dimensions (A-Scan for one-dimensional depth information, B-scan for two-dimensional cross-sectional information, C-scan for three-dimensional information) for better surgical results [18].

One group of researchers integrated an OCT fiber into a portable MSR with a piezomotor, and feedback data from the OCT-A scan was used to achieve an active depth blocking function, which effectively improved the stability of the surgeon’s exciting actions. Another group developed OCT forceps, surgical forceps with the OCT B-Scan function, which were mounted on a teloperative MSR to enable the peeling of the epiretinal membrane under the control of OCT.

There are other imaging techniques that can be integrated with MSS systems to provide intraoperative guidance. One of these methods is probebased confocal laser endomicroscopy, which uses a fiber-optic probe to capture in vivo tissue images at the cellular level (with a resolution of up to 1 μm). It allows on-site diagnostics in real time and can generate larger maps of tissue morphology, performing mosaic functions. A power-operated hand-held robot has been developed to assist in obtaining sequential images during transanal endoscopic microsurgery. A group of specialists used the probe as an end effector for a collaborative robot, and a hybrid control system was also proposed to improve image quality during robotic intraocular non-contact retinal scanning using a probe [19].

Another imaging method that has gained popularity in recent years is an exoscope, which is essentially a high-resolution video camera mounted on a long bracket. It is used to observe and illuminate the field of an object on a patient from a location remote from the patient’s body, as well as to project high-resolution 136 | Cardiometry | Issue 31. May 2024

magnified images onto a monitor to assist the surgeon. Compared to an operating microscope, the exoscope has a longer working distance and provides better image quality and greater comfort for the surgeon. Currently, the effectiveness of the exoscope has been confirmed in neurosurgery and spinal surgery [20].

Ultrasound biomicroscopy (UB) is another imaging technology that may be useful for MHS. It uses high-frequency sound waves (35-100 MHz, higher than conventional ultrasound) to visualize the internal structures of tissues with high resolution (20 microns in the axial direction and 50 microns laterally for a 50 MHz sensor), and penetration into tissues is approximately 4-5 mm. It is mainly used to visualize the anterior segment of the eye. Compared to OCT, which is also widely used in ophthalmology, UBW can provide better penetration through opaque or cloudy media, but has a relatively low spatial resolution, requires eye contact and is highly dependent on the operator. Integrating UBW technology into MSS systems can help surgeons identify tissue features and provide intraoperative imaging.

CONCLUSIONS

Robotics, a rapidly developing discipline, is changing the practice of neurosurgery thanks to advances in machine learning and artificial intelligence. The use of robotics in neurosurgery can effectively eliminate mechanical errors, reduce surgery time, and prepare more advanced appropriate fields using surgery with minimal access. Thus, minimal complications and excellent surgical results will be achieved.

As a rule, robotic systems can be used in neurosurgery for procedures with limited operating space. Anatomical localization, stabilization of the surgeon’s arm, placement of transpedicular screws during spinal surgery and access plans to deep brain objects are some of the applications of robots in neurosurgery

Visualization is an important parameter of robotic surgical systems, which can directly affect the accuracy of the operation. Intraoperative imaging or real-time imaging can show the incision and placement of instruments and is therefore a suitable tool to improve the accuracy of surgical procedures. However, its use together with the guiding lever can reduce the physical fatigue of the surgeon. Intraoperative imaging can be used to determine the optimal surgical trajectory and therefore leads to surgery with fewer invasions and side effects.