Rosa magazine
Beike Rosa Shenwai weekly No.5
Shenwai front news, according to statistics, in the preoperative evaluation of drug-resistant epilepsy, nearly 20% - 40% of patients failed to find visible lesions on MRI, and the number of such MRI negative epilepsy cases is still increasing. How to improve the diagnosis and surgical effect of MRI negative epilepsy has become the focus of the diagnosis and treatment team of epilepsy centers at home and abroad.
Professor Zhang Rui's team from epilepsy center of Brain Hospital Affiliated to Nanjing Medical University shared the application of Rosa robot assisted system in SEEG implantation of MRI negative frontal lobe epilepsy.
According to Professor Zhang Rui, the implantation of intracranial electrode mainly includes the implantation of subdural electrode, the implantation of deep electrode assisted by stereotactic frame and the combined application of the two; the implantation of cortical electrode is more traumatic, with more complications such as infection and bleeding, and it is not easy to cover the deep structures such as hippocampus, insula and cingulate gyrus; while the implantation of electrode assisted by stereotactic frame is less traumatic However, the patients suffered a lot when installing the headstock, and the operation was relatively complex and time-consuming; while the frameless positioning assistant system guided electrode implantation was simple and time-consuming, and the patients suffered less and the error was small.
Nanjing brain hospital established a functional neurosurgery specialized in neuroregulation in 2017, and introduced Rosa neurosurgery robot, surgiplan operation plan system, intraoperative electrophysiology and other equipment to carry out SEEG deep electrode implantation, DBS, brain tumor localization and biopsy, etc., which has achieved good response in the industry.
Rosa-seeg procedure - VIDEO
Directly click the above figure to watch it; or directly open https://showmore.com/zh/u/5b6xulm? Popwin = false
The key points of the interview are as follows:
1、 The diagnosis and surgical effect of MRI negative epilepsy
Extradivine front: is it difficult to diagnose epilepsy with MRI negative in epilepsy surgery? What method do you use to diagnose it?
Zhang Rui: in epilepsy surgery, we often encounter patients with drug-resistant epilepsy who are MRI negative, which really adds difficulty to preoperative evaluation and formulation of operation plan.
For MRI negative temporal or frontal lobe epilepsy, the first symptomatic diagnosis is temporal or frontal lobe epilepsy. On this basis, other auxiliary examinations are needed, mainly depending on the prompts of EEG and MRI. If there are difficulties or doubts in the diagnosis of temporal or frontal lobe epilepsy, or some uncertainties, some other examinations, including magnetoencephalogram and pet, are also needed; Of course, more difficult patients may need some intracranial electrodes to finalize.
The accurate localization of epileptogenic focus needs comprehensive evaluation. The main preoperative examinations include MRI, fMRI, EEG, VEEG, Meg, PET-CT and so on. These are noninvasive evaluation stages, or phase I evaluation. On this basis, when there are still some difficulties or doubts in localization, the accurate localization needs to be invasive and can be performed surgically After the implantation of the intracranial electrode, video EEG was detected.
Shenwai Frontier: which can be diagnosed by scalp electroencephalogram, which should use intracranial electrodes? Is intracranial electrode more helpful to determine the origin of temporal lobe or frontal lobe epilepsy?
Zhang Rui: we know that the temporal lobe is divided into left and right temporal lobes. Sometimes the main puzzle to determine temporal lobe epilepsy lies in which single side or both sides the epileptic foci are located, but in many cases, it is difficult to distinguish the side of the origin of temporal lobe epilepsy clearly; scalp EEG sometimes has these difficulties or doubts in the diagnosis of temporal lobe epilepsy, such as: when epilepsy occurs, due to various reasons, it is bilateral in EEG, but in fact, the patient It may be unilateral, which depends on more accurate stereotactic EEG.
Relatively speaking, the accuracy of stereotactic EEG is higher than that of scalp EEG in time and space resolution. Therefore, stereotactic EEG is very helpful for the diagnosis of some patients with temporal lobe epilepsy who have doubts on the location side.
Shenwai Frontier: what are the specific aspects of phase II evaluation?
Zhang Rui: in phase I, it is difficult or doubtful to distinguish whether it is the origin of temporal lobe or the origin of unilateral temporal lobe or bilateral temporal lobe, or whether the frontal lobe is one of the origins, or whether the frontal lobe is affected during the attack, i.e. it can not be completely confirmed that it is only the origin of temporal lobe, so it is very necessary to evaluate the stereotactic EEG.
In addition, temporal lobe epilepsy, phase I assessment can determine the lateral, but its origin is mainly deep (hippocampus or amygdala hippocampus,) or neocortex, that is, is the cortex outside the temporal lobe its origin? In contrast, phase II assessment will make some unclear points in phase I assessment, such as left and right temporal lobes, frontal lobes and temporal lobes, medial or lateral temporal lobes, etc.
The purpose of phase II evaluation is to further narrow or clarify the origin of epilepsy. If it can be confirmed that the epilepsy originated from the medial temporal lobe, doctors do not need to remove the external side of the patient's temporal lobe. As long as the medial structure is removed, the epilepsy can be controlled and the surgical effect can be achieved. If the diagnosis is not clear, when the frontal lobe, especially the orbital frontal part, is affected by the temporal lobe, only the temporal lobe, including neocortex and medial node, is surgically removed In fact, the operation effect is not good.
In conclusion, it is very necessary to evaluate the second stage, i.e. the intracranial electrode, when there is doubt or can not be completely accurate positioning through noninvasive phase I evaluation.
Shenwai Frontier: how to evaluate the operation mode and postoperative effect of MRI negative epilepsy? Is this closely related to the precise location of epileptogenic foci?
Zhang Rui: there are many kinds of operation methods for epilepsy. The most ideal and effective method is epileptic focectomy, which is one of the internationally recognized methods at present. But before operation, the epileptic foci must be accurately located. Generally, the curative effect is relatively good after strict preoperative evaluation and reasonable operation, and the result of epileptic localization of MEG is basically the same as that of preoperative comprehensive evaluation.
Extradivine front: is the choice of epilepsy surgery to be damaged or surgical resection?
Zhang Rui: if the focus range is not large, it can be damaged by radio frequency. This method is very simple. Patients do not need to go back to the operating room and directly adjust different contacts at the bedside.
Of course, case selection is very important. If the scope of epileptogenic foci in this case is very large, and the scope that needs to be damaged is also very large or even cannot be done, because the number of implanted electrodes is limited, and its purpose cannot be achieved, there is no need to do damage.
About 50% of epilepsy patients in our center can be damaged after stereotactic electroencephalogram, and repeatedly damaged, the damage effect is better, so some patients avoid secondary surgery; of course, some patients with poor effect, we observe for three months, half a year or even a year, if the patients still have seizures, the existing effect is not satisfied Or you can choose to resect.
2、 Function and orientation of surgical robot
Shenwai Frontier: where is the advantage of Neurosurgery Robot in deep brain electrode implantation?
Zhang Rui: in deep brain electrode implantation, the most important role of neurosurgery robot is to assist doctors to accurately place the electrode where they need to put it, reflecting its advantages of accuracy, efficiency and safety.
Shenwai front: how many electrodes are implanted in this case of MRI negative epilepsy? How long does it take?
Zhang Rui: the number of electrodes needs to be determined according to the patient's symptomatology and the comprehensive evaluation of preoperative examination. We usually choose about 10 electrodes.
In terms of time, the relative efficiency of the robot is higher, especially for the stereotactic EEG, when more than ten electrodes are completed at one time, the neurosurgery robot is very convenient, almost 360 degrees without dead angle, and 2-3 times faster than the traditional head rest operation, and the trauma of patients is relatively small.
Shenwai Frontier: is robot assisted electrode implantation more accurate than traditional frame assisted surgery?
Zhang Rui: deep brain electrode implantation can be divided into stereotactic frame assisted deep brain electrode implantation and robot frameless stereotactic surgery assistant system (Rosa). The error of stereotactic headstock is about 1.5mm; the error of Rosa auxiliary system is less than 1mm.
At present, it is believed that the accuracy of Rosa robot assisted electrode implantation is equal to or even better than the traditional frame assisted surgery.
Shenwai Frontier: compared with epilepsy SEEG implantation, the accuracy of neurosurgery robot is mainly reflected in DBS operation? What are the registration error requirements?
Zhang Rui: accuracy is a basic requirement of various stereotactic operations. At present, European studies report that the average error of deep brain stimulation (DBS) is 0.42mm. We use Rosa to assist pd-dbs, the registration error is less than 0.4mm, and the error requirement of the auxiliary SEEG implantation system is about 1mm.
Extradivine Frontier: on electrode implantation, traditional craniotomy and neurosurgery robots guide drilling, which is less risky and less traumatic?
Zhang Rui: the implantation of transcranial cortical electrodes is more traumatic, with more complications such as infection and bleeding, and it is not easy to cover the deep structures such as hippocampus, insula, cingulate gyrus, etc.; while the implantation of electrodes assisted by stereotactic frame is less traumatic, but it is more painful to install the head rest, and the operation is relatively complex and time-consuming; the operation of guiding electrode implantation without frame stereotactic auxiliary system is simple Short time, less pain and less error.
Stereotactic EEG uses a small drill bit of two or three millimeters to connect the skin, along the subcutaneous tissue and bone, to break through the bone all the time. There is no need to take a knife to cut the scalp on the skin, so the upper part of the scalp takes less into account, mainly considering intracranial blood vessels and other issues.
Shenwai Frontier: what are the similarities and differences between SEEG electrode implantation and DBS under the guidance of Rosa in image fusion and operation planning, especially how to accurately plan the path and avoid blood vessels?
Zhang Rui: Rosa robot assistant system has powerful image processing ability. It can carry out personalized operation path according to the shape of cerebral blood vessels in the fusion image of MRI and CTA, which makes the design basis of the access point more sufficient.
DBS requires higher and more accurate. Preoperative scanning MRI, including 3dt1, 3dt1 enhancement, T2, transmits the obtained image data to the Rosa robot computer workstation, accurately fuses all images, and sets the target as the corresponding nucleus. According to the results of vascular development, the surgical incision and puncture path are planned to avoid the sulcus, vessels, ventricles and reduce the chance of bleeding.
3、 Application and development of surgical robot
Shenwai Frontier: what projects / applications has the neurosurgery robot assistant system of your center carried out?
Zhang Rui: mainly engaged in Rosa guided deep brain electrode implantation (SEEG), Rosa assisted deep brain electrical stimulation (DBS) implantation, brain tumor localization and biopsy, etc.
Extradivine Frontier: what are the advantages and scope of Neurosurgery robots in biopsy?
Zhang Rui: with the advancement of precision medicine, the number of biopsy of deep brain lesions is increasing year by year. Stereotactic brain biopsy can reach most brain areas, including the deep brain, basal ganglia, sellar region, pineal region, midbrain, pons, cerebellum, etc.
Stereotactic biopsy is fast, minimally invasive and safe, which is an ideal strategy for accurate diagnosis and treatment of brain stem and deep brain diseases.
Shenwai Frontier: what are the similarities and differences in the registration methods among several applications of surgical robots?
Zhang Rui: under the guidance of Rosa, SEEG uses facial laser registration; under the assistance of Rosa, DBS uses bone mark injection