1, people and tools After more than 10 years of development, neuronavigation surgery has made great progress in terms of equipment and technology, etc., and is widely used. Since the introduction of neuronavigation system in China in 1977, now China has more than 100 sets of neuronavigation system and three sets of iMRI, among which the neurosurgery department of Huashan Hospital now has six sets of imported and domestic neuronavigation system and two sets of iMRI. The application of advanced navigation systems will undoubtedly greatly promote the development of micro-invasive neurosurgery in China for the benefit of the majority of patients. However, it must be soberly recognized that the navigation system is at best only a surgical tool, which must be used by people in order to play its role. The wisdom of the latter and the “three bases” (basic theory, basic knowledge and basic skills), especially microsurgery techniques are the key to ensure the success of navigation surgery. It must be seen that microscopic neurosurgery is not yet popular in China, and the quality still needs to be improved. Therefore, at the time of promoting and applying navigation surgery, more efforts should be made to popularize and improve microscopic neurosurgery. Any advanced equipment and instruments can not be perfect, have their advantages and disadvantages. Modern navigation system is no exception, there are its inherent shortcomings and deficiencies, affecting its accuracy, so when using it should be fully understood, in order to maximize its advantages, minimize or avoid its negative impact. Therefore, in the face of modern medicine in the 21st century, various high-precision diagnostic and therapeutic instruments and devices are emerging, we should be aware of the importance of the correct relationship between “human and material”, and emphasize that the “three fundamentals” are fundamental to sustainable academic development. 2. Development trend Computer and software of navigation system. (1) The development and application of rapid processing systems will enable computer-based application technologies to reach previously unimaginable levels. The improvement of the performance of personal computers may replace the workstations currently used, so that navigation systems will not only be greatly reduced in size or portable, but also be sold at a lower price. (2) The development of high-resolution stereoscopic monitor screens will facilitate 3D display of complex structures in the deep brain. (3) Hard and software development Make the application of navigation system easier, highly automated and intelligent equipment, and can automatically register and correct deviations. Touch control panel application allows neurosurgeons to manipulate the console directly, eliminating the need for technician assistance. (4) Multi-image fusion Automatic fusion of multiple images (CT, MRI, fMRI, DTI, MRA, MRS, PET, CTA, etc.) not only provides surgeons with more options and messages, making navigational surgery safer and more effective, but also has the following advantages: ① Provides not only an accurate localization of the lesion anatomy, but also the functional area of the peripheral cortex of the lesion (fMRI) white matter conduction tract (DTI) (2) provide information on cerebral blood supply (diffusion MRI), cerebral metabolism (PET) and early cerebral ischemia (perfusion MRI); (3) provide 3D images of cerebral vessels (MRA, MRV), which are favorable for aneurysm neck clamping and avoid damage to the aneurysm-carrying artery and important penetrating branches; (4) make low-field iMRI function as high-field iMRI, i.e., use preoperative diagnostic high-field MRI images with low-field iMRI. High-field MRI images are fused with low-field intraoperative MRI images, which not only improves the quality of anatomical localization images of lesions and allows the operation of high-field intraoperative MRI, but also greatly saves surgical time and costs; ⑤ individualized, optimal surgical plan and access design, preoperative simulation demonstration. (5) Development and application of virtual simulation (VR) technology VR allows neurosurgeons to demonstrate each operative step of surgery and the problems that may be encountered and possible countermeasures to deal with them preoperatively. This will greatly improve the quality of the individual surgical plan design for each patient, making navigational surgery more individualized, safe and effective [58, 59]. At the same time, the application of this technique will benefit not only the training of young neurosurgeons, but also the preoperative review and preparation of experienced neurosurgeons for complex surgeries (6) Automatic correction of brain shift By researching and developing brain shift correction software (for different positions, different surgical approaches, different bone window sizes, etc.), it is expected to correct this error and improve the accuracy and safety of navigated surgery. (7) Development of low magnetic field intraoperative MRI capabilities Low magnetic field intraoperative MRI can detect intraoperative brain shift and deformation, provide real-time brain anatomy images, and provide a basis for real-time lesion localization, finding and judging the extent of resection. Although fMRI with 0.15 T intraoperative MRI has been recently reported (Azmi, 2007) [60], it does not provide other images of brain function, such as DTI and MRS. Although high magnetic field intraoperative MRI can provide images of brain function, it is controversial and difficult to acquire these time-consuming images intraoperatively. The Department of Neurosurgery of Shanghai Huashan Hospital and the Digital Medicine Research Center of Fudan University applied physical or mathematical models of rigid and non-rigid registration methods and multi-image fusion techniques to fuse preoperative 1.5 T DTI images with 0.15 T intraoperative MRI images to guide intraoperative tumor resection with initial success. This technique has yet to be validated for accuracy with a large sample. (8) Optimization of iMRI hardware In order to transform diagnostic, closed MRI, into operable MRI, the conflicting physical properties of magnetic field forces and open magnets must be overcome and balanced in the design of iMRI systems. First-generation vertical open intraoperative MRI, such as the 0.5T Signa system developed by GE in collaboration with Brigham and Women’s Hospital, offered the advantage of relatively less restriction and near-uninterrupted image acquisition, but limited not only patient positioning but also surgeon maneuverability due to the small space between magnets range and space. Although the 2nd and 3rd generation intraoperative MRI can be used to overcome these problems by moving the magnet or the patient’s surgical bed, the need for interruption of the procedure, repeated multiple registrations, and sterile isolation will additionally increase the operative time and the possibility of contamination. With the development of the magnet manufacturing process, it is possible to ensure the acquisition of high-quality images while providing a spacious space that not only facilitates the placement of patients in various positions, but also facilitates uninterrupted surgical operations and truly realizes real-time navigation surgery. The use of parallel or multi-channel technology, so that it has a more powerful gradient, can be dynamic image acquisition, intraoperative image acquisition quickly, or even to achieve continuous, without having to interrupt the operation due to the acquisition of images. Using special image anti-interference technology, future image acquisition will not be disturbed by external factors, such as the activity of the surgeon’s hands or instruments, radio frequency noise caused by bipolar, etc. iMRI will develop toward miniaturization and high resolution, so that navigation surgery can truly achieve intraoperative real-time positioning and navigation. (8) Robot and remote control surgery (telesurgery) Recently there has been the application of robot or robotic arm to manipulate the operating microscope, grinding drill, retractor, electrode, endoscope, etc., without the impact of manual tremor, shaking or the surgeon’s physical strength and emotion. In the near future, robots under the control of surgeons to perform some surgical procedures DD remote control surgery, may become a reality. As 30 years ago, the aircraft landing and takeoff must be operated by the pilot himself, today’s fully automated navigation system to replace the human manipulation, the driver only has to monitor the navigation system through the monitoring system work. 3, the concept of neurosurgery changes Currently iMRI navigation surgery is mainly used for brain tumors, especially gliomas, pituitary tumors, brain metastases, etc., and will likely be expanded to benign intracranial tumors, cerebrovascular disorders, functional neurosurgery, intravascular interventions, etc. Due to the application of iMRI navigation technology, some traditional surgical concepts will be revolutionized. For example, in the past, brain thermal destruction surgery required craniotomy, where focused ultrasound or laser was introduced into the skull to act on the target point to achieve the treatment purpose. With the application of intraoperative MRI navigation technology, it is not necessary to open the skull, and the focused ultrasound is applied to the target point in the skull under the precise 3D guidance of intraoperative MRI, with no damage to the surface of the target point and the surrounding normal neurovascular, with an error of ≤1mm. intraoperative MRI not only provides precise positioning and guidance, but also monitors the temperature of the target area and controls the degree of thermal destruction, truly achieving the requirements of micro-invasive or non-invasive surgery. Recently, the FDA has approved this technique for the treatment of uterine lesions, and it is being investigated for breast cancer and liver cancer. The application of MRIgFUS system developed in Israel and USA is undergoing clinical phase I/II treatment for recurrent glioblastoma.