After the 1950s, the rapid development of science and technology, among which the three fields of information technology, life science and new material science are the most rapid, has driven the medical progress, and neurosurgery is one of the most benefited disciplines. Minimally invasive neurosurgery, marked by the application of the operating microscope, has become a milestone in the history of recent neurosurgery development, bringing neurosurgery into a brand new stage.
The establishment of minimally invasive neurosurgery has significantly improved the treatment level of neurosurgery, and minimally invasive neurosurgery techniques were popularized in the field of neurosurgery in the world in the 1980s. Minimally invasive neurosurgery in China was established in the 1970s, after more than 20 years of efforts to achieve significant development, in the treatment of intracranial tumors, aneurysms, arteriovenous malformations, spinal cord tumors, etc. has accumulated a lot of clinical experience.
I. Concept of minimally invasive neurosurgery
Minimally invasive neurosurgery is marked by the application of surgical microscope, but we must not one-sidedly understand minimally invasive neurosurgery as long as the use of surgical microscope in surgery is micro neurosurgery. The correct concept of minimally invasive neurosurgery refers to a set of surgical equipment and instruments that are compatible with microsurgery, based on recent imaging as a diagnostic basis, and a set of surgical equipment and instruments that are compatible with microsurgery to ensure that the intracranial lesion is the center of the surgery, striving to obtain the maximum therapeutic effect with minimal damage. Minimally invasive neurosurgery is not only the technology, but more importantly, the renewal of the concept.
Minimally invasive neurosurgery pushes the classical neurosurgery “lobe-wide surgery” to the level of “focal surgery”, minimizing interference with brain tissue and exploring new surgical approaches. The common feature of these representative microsurgical approaches, such as the pterygopoint approach, the transcranial approach, and the frontal orbitozygomatic approach, is that they sacrifice part of the skull base bone structure to obtain the surgical space to reach the lesion through the extracerebral area, minimizing the strain and damage to the brain.
In the 1970s, Yasargil proposed the use of natural intracranial anatomical gaps and extracerebral access to the lesion site to treat the lesion and reduce surgical trauma, which became the basic concept of minimally invasive neurosurgery. With the progressive understanding of brain function, various nerves and cerebral blood flow were also monitored during surgery, increasing the functional protection of the brain and nerves.
2, a new mode of surgical operation under the operating microscope: neurosurgery is developed from surgery, classical neurosurgery period, surgery requires 2 to 3 physicians to complete, the emphasis in surgery is on the mutual cooperation between physicians. In contrast, in microscopic neurosurgery, numerous microsurgical instruments are applied to replace the function of human hands, such as automatic brain retractor, which replaces the assistant pulling the brain pressure plate; the light of the microscope replaces the brain pressure plate with light, etc. The main key operations in surgery are basically done by one physician.
In addition, in order to reduce surgical damage and narrow the surgical field, it is impossible to accommodate too many surgical instruments for operation, which requires the surgeon to strengthen his training, especially the coordination of the operator’s own sub and eye coordination, left and right hand movements. In microsurgery, the surgeon’s eyes are required to leave the eyepiece as little as possible and use afterimages and the proprioception of the hand to find and exchange the instruments in the hand. The surgeon should also learn to use the right hand to change instruments with the instrument nurse.
The bipolar electrocautery forceps and tampon plates commonly used in surgery are placed within the surgeon’s peripheral vision. The surgeon also needs to use his or her own proprioception to perform certain actions during surgery, such as fixing the surgeon’s right foot on the foot brake of the bipolar electrocoagulation or cranial drill and the left foot on the ultrasound suction pedal.
In order to minimize interference with brain tissue and reduce frequent instrument changes, it is also important to give full play to the role of the instruments, such as the suction device can be used as a retractor, and the bipolar electrocoagulation forceps can be used as a stripper for separating blood vessels and nerves in addition to holding tampons and gelatin sponges. Minimal change of instruments during surgery can also save surgical time.
Second, microscopic neurosurgery related knowledge and techniques
1, microscopic neuroanatomy: under the microscope, the anatomical tissue is magnified several times or dozens of times, in order to meet the needs of microsurgery, since the 1960s, in some countries such as Europe and the United States neurosurgery, the rise of microscopic neuroanatomy research, to provide new clinical microscopic neuroanatomical information.
Microscopic neuroanatomy includes two parts: brain (nerve, blood vessel) and skull base, where the microscopic neuroanatomy of the brain takes the cerebral artery as a clue, and the microscopic anatomy of the skull base is divided into saddle area, pontocerebellar area and slope area: after more than ten years of continuous efforts, the international neurosurgery community, has completed the practical research work of brain microanatomy, for the popularization and standardization of microscopic neurosurgery, laid a solid foundation, the current microsurgery Training, is no longer the learning of microscopic neuroanatomy, but the use of microsurgery technology platform, simulation of the actual surgical approach and trial a variety of new surgical instruments.
2, microscopic neurosurgery instruments and equipment: “to be good at what it does, it must first benefit from its tools. Microscopic neurosurgery can be completed with high quality, and excellent microscopic neurosurgery equipment and instruments are inseparable Microscopic neurosurgery equipment is not fully equipped, poor quality or improper use, will affect the effect of microscopic neurosurgery.
A series of microsurgical instruments (materials) with the operating microscope as the core, such as high-speed cranial drill, controlled operating bed and head frame, automatic brain retractor, ultrasonic suction device, bipolar electrocoagulation, hemostatic gauze and other applications have solved the problems of lighting, narrow operating space and hemostasis that are different from other surgeries in confusing neurosurgery. Microscopic neuroanatomy goes hand in hand with the consolidation and improvement of surgical techniques.
Microscopic neurosurgical anatomy is important for both the improvement and refinement of traditional surgical techniques and the adaptation to new conditions. Each year new advances in neurosurgical techniques are made to adapt to the needs of patient care, and none of these new techniques are the result of work based on an in-depth understanding of microscopic neurosurgical anatomy.
The combination of the operating microscope and microscopic neuroanatomy will lead to further refinement of many routine neurosurgical procedures, such as spinal cord resection and aneurysm clamping, and create procedures that previously could not be performed by neurosurgeons. Due to the deeper understanding of microscopic neuroanatomy, surgeons are able to safely and accurately reach deep brain lesions through the neurovascular gap with smaller brain retractions or cortical structure incisions to perform micro-invasive surgical resections.
In conclusion, the combination of microscopic neuroanatomy and microsurgical techniques allows for the minimally invasive removal of lesions that previously could not be surgically removed. The application of the operating microscope for neurosurgical anatomy research and neurosurgical teaching is a new revision of the previous naked-eye neuroanatomy research, which makes the tiny structures and delicate nerves that are difficult to observe with the naked eye clearly discernible and belongs to a completely new field.
The application of the surgical microscope has made surgeons feel limited in terms of flexibility and precision, so some scholars have begun to explore robot-assisted surgery, which will create a new realm of fine surgical techniques, but of course it also requires new knowledge of microscopic anatomy to adapt to it. The development of other new techniques also requires precise knowledge of microscopic neuroanatomy, such as endovascular embolization of aneurysms, which requires detailed knowledge of the aneurysm-carrying artery, the penetrating artery, and its anatomical variants to reach any part of the skull base after meticulous craniotomy design.
By combining microscopic neurosurgical anatomical studies with imaging localization, some deep brain anatomy can be ideally exposed by using the sulcus of the brain surface to create small orifices. Microanatomical studies have also investigated new surgical approaches, such as the transchoroidal approach to the third ventricle and the transnasal approach to the pterygoid sinus for pituitary tumors. In the future, more in-depth microsurgical anatomy studies will lead to new and better surgical approaches. In addition, the improvement and refinement of some new surgical techniques will require a deeper understanding of microsurgical anatomy.