I. Movement disorders Deep brain stimulation (DBS) can treat all kinds of brain function disorders, and movement disorders are its main indications, especially Parkinson’s disease (PD). Today, DBS is performed on more than 140,000 patients in 500 centers worldwide. In the past year of 2014, the Department of Functional Neurosurgery of Beijing Tiantan Hospital has become the largest DBS implantation center in the world, benefiting from the localization of DBS devices. The long-term efficacy and stability of DBS for PD has now been demonstrated, and a 2013 article by Schuepbach in the New England Journal further confirms the advantages of early DBS for PD. The anterior thalamic nucleus (STN) and the medial pallidum (GPi) are the most common targets of DBS for PD, and the superiority of the two has been the subject of academic debate.
A recent randomized controlled study published in Lancet Neurology showed no difference in the effect of the two targets on cognition, while STN was more effective in improving motor symptoms.STN and GPi are not effective in PD midline symptoms, and for patients with predominantly midline symptoms, pontine nucleus (PPN) electrical stimulation or combined STN+PPN electrical stimulation can be used. New DBS targets are gradually gaining attention, such as the substantia nigra, the unsettled zone of the thalamus and the parabrachial nucleus complex of the central median nucleus. In the basic research direction, the local anatomy, local field potential changes and optogenetics of the stimulation targets are at the forefront of research, and the results are expected to further improve the surgical efficacy in the future.
Dystonia (DT) is a common movement disorder second only to Parkinson’s disease. The ventral intermediate nucleus of the thalamus (Vim) and GPi DBS can be used to treat primary DT, but double-blind prospective studies suggest that GPi may be a better choice for primary DT. STN-DBS was the first to be reported in China for the treatment of primary dystonia with very good results. In addition, DBS can also be used to treat some other types of dystonia, such as craniofacial dystonia (Meige), spastic squint, post-traumatic, post-hypoxic, dystonia superimposed syndrome and tardive dystonia (TD), especially TD, with perfect results.
In 2014, Plaha et al. suggested that STN, unspecified band or anterior thalamus radiation may be a better target for some patients with idiopathic tremor.
In 2014, the Lasker Prize in Medicine, known as the Nobel Prize, was awarded to Professors Benabid and DeLong for their contributions to the invention and mechanism of DBS technology. The U.S. Brain Project, which has already begun, and the upcoming Chinese Brain Project will take the prevention and treatment of functional brain disorders to an unprecedented level. Neuromodulation for the treatment of functional brain disorders will be at the forefront of research throughout neurosurgery in the future.
Epilepsy In the field of preoperative evaluation of epilepsy, the Epileptogenic Zone (EZ) localization theory is gradually changing from the North American school to the French school. Stereotactic electroencephalography (SEEG) is a preoperative assessment method with higher temporal and spatial resolution and deeper localization than conventional electrophysiological assessment. By analyzing the symptomatology of SEEG electrode recordings, scholars have identified new symptomatological patterns in different brain regions.14 Bonini discovered the phenomenon of hierarchical control regarding frontal lobe symptomatology in 14 years. Another hot topic in epilepsy electrophysiology is the high frequency oscillation (HFO), the presence of which mostly implies the EZ area and therefore suggests a good prognosis. In the case of epilepsy, the common evaluation modalities include MRI, PET-CT, SPECT and MEG; however, in the case of FCD Ia/b, which is highly epileptogenic, the imaging is often negative. Novel imaging post-processing analyses such as T1WI-3D-MP RAGE MRI, voxel-based morphologic analysis and PET-MRI fusion are now available for such patients to improve the sensitivity of localization and diagnosis. Other advances in preoperative evaluation techniques include EEG-fMRI, high-resolution EEG, EEGLAB electrical signal analysis, and 7T MRI, among others. In addition, there is a shift in the definition of the epileptogenic focus from a single focal origin to an epileptic network.
In terms of epilepsy surgery, one of the most influential recent clinical studies is the 2012 study by Professor Engel comparing early surgery with AEDs in patients with temporal lobe epilepsy 2 years after diagnosis, which demonstrated the benefits of early temporal lobe epilepsy surgery. Recent meta-analyses have shown seizure eradication rates of 66% to 71% after temporal lobe epilepsy surgery. The hemisphere surgery has been modified from anatomic hemisphere resection to hemisphere dissection, and recent clinical studies have demonstrated its advantages in younger patients, with meta-analysis showing a 73% postoperative seizure cure rate, even better than temporal lobe epilepsy. For patients with posterior involvement of the lesion, surgeons can now also perform posterior quarter dissection. In the field of neuromodulation, vagus nerve stimulation (VNS) and anterior thalamic nucleus deep brain stimulation (ANTDBS) are currently the mainstays. In June of this year, VNS was approved by the FDA as a closed-loop electrical stimulation method for monitoring heart rate. Also this year, the SANTE study published the long-term efficacy of ANTDBS, with 68% of patients experiencing more than a 50% reduction in seizures. Other hot topics include closed-loop electrical stimulation, trigeminal nerve external electrical stimulation, and other targeted DBS electrical stimulation. In conclusion, with the rapid development of surgical techniques in recent years, epilepsy surgery has formed a whole spectrum of procedures with different invasiveness corresponding to the size of epileptogenic foci.
At present, epilepsy surgery in China faces the problems of uneven distribution of superior resources, limited number of epilepsy centers, lack of recognition by other disciplines, and low volume of surgery with a large patient base. In the future, it is necessary to deepen the cooperation with other multidisciplinary disciplines to increase the number of epilepsy centers and promote epilepsy surgery, while vertical cooperation with other fields should be carried out, focusing on basic research while strengthening the transformation of industry-university research. Create a three-dimensional cooperative network of research and treatment belonging to epilepsy surgery.
Cranial nerve diseases Microvascular decompression (MVD) is the surgical method of choice for the treatment of trigeminal neuralgia, facial spasm, glossopharyngeal neuralgia and other cranial nerve disorders, and is considered to be one of the most important breakthrough innovative techniques in the treatment of modern neurological diseases. With the further development of micro-neurosurgery techniques and in-depth research on the pathogenesis of cranial nerve disorders, MVD is gradually used to treat other cranial nerve disorders such as disabling vertigo, refractory tinnitus, and primary hypertension. In the past 30 years, MVD has developed rapidly in China, but it is still not popular, and there is a great imbalance between regions, and the overall treatment level of cranial nerve disorders needs to be improved. Try to improve the efficacy of surgery and reduce its complication rate is the direction of future efforts.
DBS can treat obsessive-compulsive disorder, depression, anorexia nervosa, Tourette’s syndrome and drug addiction. China is at the forefront of this field internationally, having first reported DBS for drug addiction and anorexia nervosa. In addition, initiated by China, the World Society for Functional Neurosurgery Committee on Surgical Treatment of Psychiatric Disorders convened more than 20 countries and regions around the world, and together with the World Psychiatric Association and regional functional neurosurgery societies, jointly published the Expert Consensus on World Clinical Guidelines for Surgical Treatment of Psychiatric Disorders, which will be translated into multiple languages and published worldwide. The future strategy for the surgical treatment of mental diseases in China is to establish a standardized professional committee, to build a standardized treatment process, treatment team, patient enrollment criteria, follow-up system, etc. with reference to the guidelines.
V. Localization of neuromodulation devices Since 2000, with the support of the late academician Wang Zhongli and national and Beijing ministries, Tsinghua University and Beijing Tiantan Hospital have cooperated to start the research of domestic brain pacemakers. Tsinghua University is responsible for technical research and product development, while Beijing Tiantan Hospital is responsible for animal testing and clinical trials. After more than ten years of unremitting efforts, a series of technical difficulties in electronics, software, mechanics and materials have been overcome. The domestic brain pacemaker manufactured by Beijing Pinchi Medical Equipment Co. The current product line covers single-channel, dual-channel and dual-channel rechargeable pacemakers. Up to now, the domestic pacemakers have entered more than 70 tertiary hospitals and specialized hospitals nationwide, completing more than 2,300 surgeries and reducing the burden of patients by more than 200 million RMB. Nearly one hundred patents have been born along with the R&D and production. It marks that China has become the second country in the world after the United States that has the ability to develop, produce and apply brain pacemakers, which has an extremely important demonstration significance for the development and industrialization of China’s independent high-end medical devices.
A brief history of the development of neurosurgery in China” published in the Chinese Journal of Surgery in January 2015, cites the achievement of brain pacemaker as a milestone progress. The “Tsinghua Brain Pacemaker for Parkinson’s Disease Patients” was selected as the sixth achievement in the “Science and Technology of the Decade” by Science and Technology Daily/China Science and Technology Network. “Tsinghua Brain Pacemaker Research” was selected as one of the top ten technological advances of the Ministry of Education in 2012. CCTV News broadcasted a special report with the title of “Domestic brain pacemaker breaks the exclusive technology monopoly of the United States”. The People’s Daily reported the case of developing a brain pacemaker by joint research and development with the title of “One child for all”. The research result of the brain pacemaker won the first prize of Beijing Science and Technology Progress in 2015.
In the future, this industry-university-research model will continue to cooperate to explore newer generation of pacemaker therapies and technologies (VNS instrumentation, high-field MRI-compatible technology, rechargeable pacemakers that can record deep EEG, variable frequency stimulation technology, and remote program control technology) from the perspective of disease treatment mechanism research and clinical needs. We are actively responding to the Made in China 2025 plan, closely following the research direction of the Brain Project, and making outstanding contributions to China’s neuroscience to achieve a bend in the road to overtake.