Transcranial magnetic stimulation (TMS) is a noninvasive neurophysiologic technique that can stimulate the human brain. Positioning of the coil was often performed based merely on external landmarks on the head, meaning that the anatomical target in the cortex remains inaccurate. Navigated transcranial magnetic stimulation (nTMS) combines a frameless stereotactic navigational system and TMS coil and can provide a highly accurate delivery of TMS pulses with the guidance of imaging. Therefore, many novel utilities for TMS could be explored due to the ability of precise localization. Many studies have been published, which indicate nTMS enables presurgical functional mapping. This review aimed to provide a comprehensive literature review on nTMS, especially the principles and clinical applications of nTMS. All articles in PubMed with keywords of “motor mapping,” “presurgical mapping,” “navigated transcranial magnetic stimulation,” and “language mapping” published from 2000 to 2018 were included in the study. Frequently cited publications before 2000 were also included. The most valuable published original and review articles related to our objective were selected. Motor mapping of nTMS is validated to be a trustful tool to recognize functional areas belonging to both normal and lesioned primary motor cortex. It can offer reliable mapping of speech and motor regions at cortex prior to operation and has comparable accuracy as direct electrical cortical stimulation. nTMS is a powerful tool for mapping of motor and linguistic function prior to operation, has high application value in neurosurgery and the treatment of neurological and psychiatric diseases, and has gained increasing acceptance in neurosurgical centers across the world.

Background: To describe and report the efficacy and safety of MR-guided laser interstitial thermal therapy (MRgLITT) in the treatment of drug-resistant epilepsy. Methods: A retrospective review of all MRgLITT procedures in our hospital was performed. All procedures were performed using a surgical laser ablation system. Demographic and outcome data were compiled and analyzed. Results: A total of 19 patients underwent MRgLITT procedures from June 2021 to November 2021. The average age at surgery was 18.1 years (3–61.4 years). The average length of hospitalization post-surgery was 4.95 days (4–7 days). Surgical substrates included 8 patients with hypothalamic hamartomas, 5 with medial temporal lobe epilepsy, 3 with deep focal cortical dysplasia, 1 with tuberous sclerosis, 1 with a cavernous malformation, and 1 with Lennox–Gastaut syndrome who underwent anterior corpus callosotomy. Complications occurred in three patients. After an average follow-up of 1 year, 6 patients were seizure-free (Engel I, 31.6%), 1 had significant seizure control (Engel II, 5.3%), 7 had seizure control (Engel III, 36.8%), and 5 had no improvement in their seizures (Engel IV, 26.3%). Fisher’s exact tests did not reveal statistical significance for the association between Engel class outcome and epileptic disease. Conclusion: This study confirmed that MRgLITT, as a method for treating drug-resistant epilepsy, is minimally invasive, safe, and efficient and that it can reduce the incidence of surgery-related complications.

This study aimed to investigate the value of high field-strength intraoperative magnetic resonance imaging (iMRI)-guided stereotactic biopsy in the surgery of intracranial space-occupying lesions. A total of 87 patients who underwent stereotactic biopsy of intracranial lesions in the Peking University International Hospital from March 2016 to August 2018 were retrospectively surveyed; among these, 50 patients underwent MRI-guided stereotactic biopsy using the Leksell frame (iMRI group) and 37 cases received traditional stereotactic biopsy using the Leksell frame (control group). The accuracy rates and complications of the two groups were compared. A 100% positive diagnosis was observed in all cases (n = 50) in the iMRI group. In 4 cases, the biopsy site was clearly found to have deviated from the target point, and the biopsy was performed again. The control group had 33 cases (86.5%) with positive diagnosis. No severe complications like neural functional deficit were observed in the iMRI group, while two patients developed bleeding at the puncture site (1 case receiving surgery to remove the hematoma) in the control group. There were no deaths in either group. iMRI-assisted stereotactic biopsy can confirm the target position and adjust the puncture path in real time. Compared to the traditional stereotactic biopsy technique, the iMRI method has a higher positive diagnostic rate, though surgical trauma and complications have no significant difference.

Purpose: Intracranial arachnoid cysts are common, accounting for about 1%–2% of intracranial space-occupying lesions. There is controversy over the method of surgical intervention, and in order to provide guidance for surgical decision making, this study compares the efficacy of craniotomy vs. neuroendoscopic surgery in treating arachnoid cysts.Methods: The adult patients with arachnoid cyst admitted to our department from October 2016 to August 2021 were retrospectively analyzed. Thirteen adult patients were recruited, and divided into two groups: neuroendoscopic group (group A) and craniotomy group (group B). We compared the gender, age, clinical symptoms, preoperative and postoperative cyst sizes, symptom improvement, complications, length of hospital stay, and hospital costs between two groups to analyze the therapeutic effects of these two surgical methods.Results: The cost of hospitalization in group A was significantly lower than that in group B (47,292.8 vs. 65,151.8 yuan, P < 0.05), and there was no difference in the length of hospital stay between the two groups. The preoperative cysts in group A were significantly larger than those in group B (6.38 vs. 2.97 cm, P < 0.05). In groups A and B, the short-term symptom improvement rates were 100% and 75.0%, respectively. The long-term symptom improvement rates were 77.78% and 75.0% (P > 0.05), respectively.Conclusion: Both neuroendoscopic and craniotomy have good curative effects for the treatment of intracranial arachnoid cysts. There was no significant difference in the outcomes between the two surgical techniques. The cost of hospitalization can be reduced with neuroendoscopic surgery. Neuroendoscopic treatment is recommended for large intracranial arachnoid cysts, and craniotomy is suitable for small intracranial arachnoid cysts.

Background: Intraparenchymal cerebral cavernous malformation is difficult to localize intraoperatively with conventional frameless navigation due to the “brain shift” effect. We conducted this study to evaluate the efficacy and safety of intraoperative magnetic resonance image (iMRI)-assisted neuro-port surgery for the resection of cerebral intraparenchymal cavernous malformation. Methods: Between April 2016 and December 2017, 54 consecutive patients with intraparenchymal cerebral cavernous malformation who get surgical treatment in our hospital were enrolled into this study. Twenty-one patients were treated using iMRI-assisted neuro-port surgery (experiment group), and 33 patients underwent treatment by conventional microsurgery (control group). The iMRI was used in all cases for the compensation of the “brain shift” effect and keeping the navigation system up-to-date. The surgical resection rate, the total operation time, and the preoperative and postoperative Karnofsky Performance Status (KPS) scores were determined to evaluate the operative procedures. Results: There were no significant differences between the two groups in mean age, gender ratio, and volume of lesions (P > 0.05). For the experiment group, the average duration of the procedure was 188.8 min with total resection of the lesions achieved in all 21 cases. For the control group, the average duration of the procedure was 238.2 min with total resection of the lesions achieved in 25 of 33 cases. The differences in the average duration of the procedure and the number of totally resected lesions between the two groups were statistically significant (P < 0.05). Regarding postoperative neurological function, postoperative KPS scores for the experiment group were significantly higher than those of the control group (P = 0.018). Conclusion: Our results show that iMRI-assisted neuro-port surgery is helpful for intraparenchymal cerebral cavernous malformation surgery. The method provides high accuracy and efficiency for lesion targeting and permits excellent anatomic orientation. With the assistance of iMRI technology, we achieved a higher resection rate and a lower incidence of postoperative neurological deficits. Additionally, iMRI is helpful for the compensation of the “brain shift” effect, and it can update the navigation system.