Clinical outcomes and safety of large or giant vestibular schwannoma in older patients undergoing microsurgery: a matched cohort study.

OBJECTIVE: To compare the clinical outcomes of large or giant vestibular schwannomas (VSs) between older patients and younger patients who underwent microsurgery and to explore whether the incidence of postoperative complications increased and whether the postoperative hospital stay was prolonged. METHODS: We conducted a retrospective matched cohort study based on the surgical approach, maximum tumor diameter and extent of resection. Older patients (≥ 60 years) and a matched group (<60 years) who had undergone microsurgery for VSs between January 2015 and December 2021 were included. Clinical data, surgical outcomes and postoperative complications were analyzed statistically. RESULTS: Forty-two older patients (≥ 60 years, 66.0 ± 3.8 years) were identified and matched to younger patients (<60 years, 43.9 ± 11.2 years), and they all underwent microsurgery through a retrosigmoid approach. There were twenty-nine patients with 3-4 cm VSs and thirteen patients with > 4 cm VSs in both groups. The older patients had a higher proportion of imbalance (P = 0.016) and lower American Society of Anesthesiology scores (P = 0.003) before surgery than the younger patients. There was no significant difference in facial nerve function one week (p = 0.851) and one year (p = 0.756) after surgery and no difference in the postoperative complication incidence (40.5% vs. 23.8%, p = 0.102) between the older patients and controls. Furthermore, the older patients had longer postoperative hospital stays than the younger patients (p = 0.043). In the older group, six patients with near total resection and five with subtotal resection were administered stereotactic radiotherapy, and one had recurrence three years after surgery and received conservative treatment. The postoperative follow-up time ranged from 1 to 83 months, with an average of 33.5 ± 21.1 months. CONCLUSIONS: For older patients (≥ 60 years) with symptomatic, large or giant -VSs, microsurgery is the only effective method to prolong lifespan, alleviate clinical symptoms and cure the tumor. However, radical resection of VSs may result in a decreased preservation rate of facial-acoustic nerve function and an increased postoperative complication incidence. Therefore, subtotal resection followed by stereotactic radiotherapy should be recommended.

The incidence and risk factors of unplanned reoperation in endoscopic endonasal surgeries: a single center study.

The incidence of unplanned reoperation after surgery during the same hospitalization is considered one of most important evaluation indicators for health care quality. The purpose of this study was to determine the incidence and risk factors related to unplanned reoperation after an endoscopic endonasal approach (EEA). All patients who underwent elective endoscopic endonasal surgery from January 2016 to December 2021 in the Department of Neurosurgery, Tangdu Hospital, Air Force Military Medical University, were included. We identified the patients who underwent an unplanned reoperation and those who did not and divided them into two groups. The demographic data and risk factors were compared between the groups by univariate and multivariate logistic regression analyses. Of the 1783 patients undergoing EEA for various lesions of the skull base, the incidence of unplanned reoperation was 2.3%. The most common unplanned reoperations were repair of cerebrospinal fluid (CSF) leakage (39%), sellar hematoma evacuation (34.1%), hemostasis of epistaxis (14.6%) and external ventricular drainage for obstructive hydrocephalus (9.8%). The maximum diameter of tumor ≥ 3 cm (OR 2.654, CI 1.236-5.698; p = 0.012), meningioma (OR 4.198, CI 1.169-15.072; p = 0.028), craniopharyngioma (OR 5.020, CI 2.020-12.476; p = 0.001) and other sellar lesions (OR 4.336, CI 1.390-13.527; p = 0.012) and an operation time ≥ 240 min (OR 2.299, CI 1.170-4.518; p = 0.016) were the independent risk factors for unplanned reoperations in multivariate regression analysis. Of the 41 patients undergoing unplanned reoperation, 16 patients died, twenty-one patients had panhypopituitarism, 13 patients had transient and 6 had permanent diabetes insipidus, and 11 patients presented with intracranial infection and 6 of these patients were cured. By reviewing our department's data, we stated the incidence and risk factors for unplanned reoperation. It is important for the hospital administration and neurosurgeons to place more emphasis on these indicators. Furthermore, we suggest some effective quality improvement initiatives to reduce the incidence of unplanned reoperation.

Identification of genetic determinants of hemolytic activity of Riemerella anatipestifer using random transposon mutagenesis.

Riemerella anatipestifer causes epizootic infectious disease in poultry resulting in serious economic losses especially to the duck industry. In our previous study, R. anatipestifer was found to lyse duck erythrocytes in vitro. In the present study, a random Tn4351 mutagenesis library of hemolytic R. anatipestifer strain SX containing 4000 mutants was constructed to investigate the genetic basis of hemolytic activity. Thirty mutants with reduced hemolytic activity and one with increased hemolytic activity were screened and insertions in 24 genes were identified. Of these genes, four were predicted to encode outer membrane proteins, one encoded a cytoplasmic membrane protein, 11 encoded cytoplasmic proteins, and eight encoded proteins with unknown locations. Based on current annotations of the R. anatipestifer genomes, of the 24 genes, 7 (29.17%) were involved in iron utilization. The hemolytic activities of the complemented strains M2 (pRES-Riean_0790) and M18 (pRES-Riean_0653) were restored, indicating that both Riean_0653 and Riean_0790 are involved in the hemolytic activity of strain SX. However, the recombinant proteins rRiean_0317, rRiean_0790, rRiean_0653, rRiean_1027, rRiean_1143, and rRiean_1561 had no hemolytic activity, suggesting that none were hemolysins.

Lithography-free synthesis of periodic, vertically-aligned, multi-walled carbon nanotube arrays.

Until now, the growth of periodic vertically aligned multi-walled carbon nanotube (VA-MWCNT) arrays was dependent on at least one lithography step during fabrication. Here, we demonstrate a lithography-free fabrication method to grow hexagonal arrays of self-standing VA-MWCNTs with tunable pitch and MWCNT size. The MWCNTs are synthesized by plasma enhanced chemical vapor deposition (PECVD) from Ni catalyst particles. Template guided dewetting of a thin Ni film on a hexagonally close-packed silica particle monolayer provides periodically distributed Ni catalyst particles as seeds for the growth of the periodic MWCNT arrays. The diameter of the silica particles directly controls the pitch of the periodic VA-MWCNT arrays from 600 nm to as small as 160 nm. The diameter and length of the individual MWCNTs can also be readily adjusted and are a function of the Ni particle size and PECVD time. This unique method of lithography-free growth of periodic VA-MWCNT arrays can be utilized for the fabrication of large-scale biomimetic materials.

Characterization of the hemolytic activity of Riemerella anatipestifer.

Riemerella anatipestifer infection causes serious economic losses in the duck industry worldwide. Acute septicemia and high blood bacterial loading in R. anatipestifer infected ducks indicate that R. anatipestifer may be able to obtain iron and other nutrients by lysing duck erythrocytes to support its rapid growth and proliferation in the blood. However, so far, little is known about the hemolytic activity of R. anatipestifer to duck erythrocytes. In this study, 29 of 52 R. anatipestifer strains showed hemolytic activity on duck blood agar, whereas all the tested dba+ (with hemolytic activity on duck blood agar) and dba- strains created pores in the duck red blood cells, with 4.35-9.03% hemolytic activity in a liquid hemolysis assay after incubation for 24 h. The concentrated culture supernatants of all the tested R. anatipestifer strains and the extracted outer membrane proteins (OMPs) from dba+R. anatipestifer strains showed hemolytic activity on duck blood agar. These results, together with the median lethal dose (LD50) of some dba+ and dba-R. anatipestifer strains in ducklings, suggested that there was no direct relationship between the hemolytic capacity of R. anatipestifer on duck blood agar and its virulence.

Successful implementation of an enhanced recovery after surgery (ERAS) protocol reduces nausea and vomiting after infratentorial craniotomy for tumour resection: a randomized controlled trial.

BACKGROUND: Infratentorial craniotomy patients have a high incidence of postoperative nausea and vomiting (PONV). Enhanced Recovery After Surgery (ERAS) protocols have been shown in multiple surgical disciplines to improve outcomes, including reduced PONV. However, very few studies have described the application of ERAS to infratentorial craniotomy. The aim of this study was to examine whether our ERAS protocol for infratentorial craniotomy could improve PONV. METHODS: We implemented an evidence-based, multimodal ERAS protocol for patients undergoing infratentorial craniotomy. A total of 105 patients who underwent infratentorial craniotomy were randomized into either the ERAS group (n = 50) or the control group (n = 55). Primary outcomes were the incidence of vomiting, nausea score, and use of rescue antiemetic during the first 72 h after surgery. Secondary outcomes included postoperative anxiety level, sleep quality, and complications. RESULTS: Over the entire 72 h post-craniotomy observation period, the cumulative incidence of vomiting was significantly lower in the ERAS group than in the control group. Meanwhile, the incidence of vomiting was significantly lower in the ERAS group on postoperative days (PODs) 2 and 3. Notably, the proportion of patients with mild nausea (VAS 0-4) was higher in the ERAS group as compared to the control group on PODs 2 or 3. Additionally, the postoperative anxiety level and quality of sleep were significantly better in the ERAS group. CONCLUSION: Successful implementation of our ERAS protocol in infratentorial craniotomy patients could attenuate postoperative anxiety, improve sleep quality, and reduce the incidence of PONV, without increasing the rate of postoperative complications. TRIAL REGISTRATION: ChiCTR-INR-16009662, 27 Oct 2016, Clinical study on the development and efficacy evaluation of Enhanced Recovery After Surgery (ERAS) in Neurosurgery.

Management of Postoperative Pain after Elective Craniotomy: A Prospective Randomized Controlled Trial of a Neurosurgical Enhanced Recovery after Surgery (ERAS) Program.

Objective: To prospectively evaluate the efficacy of a neurosurgical enhanced recovery after surgery (ERAS) protocol on the management of postoperative pain after elective craniotomies. Methods: This randomized controlled trial was conducted in the neurosurgical center of Tangdu Hospital (Fourth Military Medical University, Xi'an, China). A total of 129 patients undergoing craniotomies between October 2016 and July 2017 were enrolled in a randomized clinical trial comparing an ERAS protocol to a conventional postoperative care regimen. The primary outcome was the postoperative pain score assessed by a verbal numerical rating scale (NRS). Results: Patients in the ERAS group had a significant reduction in their postoperative pain scores on POD 1 compared to patients in the control group (p < 0.05). More patients (n = 44, 68.8%) in the ERAS group experienced mild pain (NRS: 1 to 3) on POD1 compared with patients (n = 23, 35.4%) in the control group (p < 0.05). A further reduction in pain scores was also observed on POD 2 and maintained on POD 3 in the ERAS group compared with that in the control group. In addition, the median postoperative length of hospital stay was significantly decreased with the incorporation of the ERAS protocol compared to controls (ERAS: 4 days, control: 7 days, P<0.001). Conclusion: The implementation of a neurosurgical ERAS protocol for elective craniotomy patients has significant benefits in alleviating postoperative pain and enhancing recovery leading to early discharge after surgery compared to conventional care. Further evaluation of this protocol in larger, multi-center studies is warranted.

Critical roles of chemokine receptor CCR5 in regulating glioblastoma proliferation and invasion.

Glioblastoma (GBM) is the most prevalent malignant primary brain tumor in adults and exhibits a spectrum of aberrantly aggressive phenotype. Tumor cell proliferation and invasion are critically regulated by chemokines and their receptors. Recent studies have shown that the chemokine CCL5 and its receptor CCR5 play important roles in tumor invasion and metastasis. Nonetheless, the roles of the CCR5 in GBM still remain unclear. The present study provides the evidence that the chemokine receptor CCR5 is highly expressed and associated with poor prognosis in human GBM. Mechanistically, CCL5-CCR5 mediates activation of Akt, and subsequently induces proliferation and invasive responses in U87 and U251 cells. Moreover, down-regulation of CCR5 significantly inhibited the growth of glioma in U87 tumor xenograft mouse model. Finally, high CCR5 expression in GBM is correlated with increased p-Akt expression in patient samples. Together, these findings suggest that the CCR5 is a critical molecular event associated with gliomagenesis.

Activation of GPER-1 Attenuates Traumatic Brain Injury-Induced Neurological Impairments in Mice.

This study aimed to investigate the effects of G1-activated G protein-coupled estrogen receptor 1 (GPER1) on neurological impairments and neuroinflammation in traumatic brain injury (TBI) mice. The controlled cortical impingement (CCI) method was used to establish the TBI model. The mice were subjected to ovariectomy (OVX) for two weeks prior to modeling. GPER1 agonist G1 was administered by intracerebroventricular injection. Brain tissue water content was detected by wet/dry method, and blood-brain barrier damage was detected by Evans blue extravasation. The neurological impairments in mice were evaluated by open field test, Y-maze test, nest-building test, object location memory test and novel object recognition test. Ionized calcium-binding adapter molecule 1 (Iba1) staining was used to indicate the activation of microglia. Expression of M1/M2-type microglia markers and inflammatory factors were evaluated by ELISA and qRT-PCR. The G1 administration significantly reduced cerebral edema and Evans blue extravasation at injury ipsilateral cortex and basal ganglia in TBI mice. Activation of GPER1 by G1 improved the anxiety behavior and the cognitive dysfunction of mice induced by TBI. G1 administration significantly decreased Iba1-positive staining cells and the mRNA levels of CD86, macrophage cationic peptide 1 (Mcp-1), nitric oxide synthase 2 (Nos2), interleukin 1 beta (IL-1ß), and macrophage inflammatory protein-2 (MIP-2), while increased the mRNA levels of interleukin 10 (IL-10), arginase1 (Arg-1) and CD206. Activation of GPER1 through G1 administration has the potential to ameliorate cognitive dysfunction induced by TBI in mice. It may also inhibit the activation of M1 microglia in cortical tissue resulting from TBI, while promoting the activation of M2 microglia and contributing to the regulation of inflammatory responses.

Surgical results, technical notes and complications of jugular foramen lesions via retroauricular infratemporal fossa approach.

OBJECTIVE: The objective of this study was to evaluate the clinical effect and safety of the postauricular infratemporal fossa approach (ITFA) in resecting jugular foramen lesions. METHODS: All 25 patients undergoing microsurgery via postauricular ITFA from March 2015 to May 2023 in the Department of Neurosurgery, Tangdu Hospital, Air Force Military Medical University were included. The clinical and radiological data were retrospectively analyzed. Regular follow-up was carried out. RESULTS: The mean age of all patients was 50.5±8.9 years, and 14 of them were female and 11 were male. Among the cases, lower cranial nerve schwannoma accounted for 60 % (15/25) of all tumors, jugular foramen paraganglioma accounted for 20 % (5/25), and the remaining 20 % included meningioma, chondrosarcoma, plasmacytoma, and salivary gland tumors. Total tumor resection was performed in 18 cases, subtotal tumor resection in 7 cases and partial resection in 1 case. Seven patients underwent gamma knife radiotherapy after surgery. Transient lower cranial nerve dysfunction occurred in 8 patients, and permanent lower cranial nerve dysfunction occurred in 2 patients after surgery. One patient developed facial paralysis, and one patient presented hearing loss. CONCLUSIONS: The postauricular ITFA achieved a relatively high total tumor resection rate and a lower incidence of neurological functional disorders. It is an alternative and suitable surgical approach for resecting jugular foramen lesions. Maximizing the preservation of neurological function is preferred, especially when radical resection cannot be achieved. Stereotactic radiotherapy could be used for residual tumors.

A multicenter retrospective analysis of clinical outcomes of intracranial chondrosarcoma in 26 patients.

Intracranial chondrosarcoma is a rare tumor with limited reports. We reviewed the clinical outcomes, imaging findings, and pathological characteristics at three centers to improve the diagnosis and treatment of intracranial chondrosarcoma. We retrospectively analyzed 26 patients with intracranial chondrosarcoma who had undergone surgical treatment at Tangdu Hospital of Air Force Military Medical University, Mianyang Central Hospital, and Nanchong Central Hospital from January 2010 to July 2022. Clinical manifestations, imaging features, surgical treatment, prognosis, and overall survival (OS) were analyzed. All 26 chondrosarcomas were located at the skull base. Gross total resection (GTR), subtotal resection (STR), and partial resection (PR) were performed in 14, 10, and 2 cases, respectively. Four cases underwent endoscopic transnasal surgery, while the remaining cases underwent craniotomy. The clinical symptoms were evaluated 1 week after surgery, and 15 cases were relieved to varying degrees. Postoperative complications included pulmonary infection, subcutaneous hydrops, dysphagia and choking, facial numbness, abducens paralysis, and intracranial infection (ICI). Fifteen cases received postoperative adjuvant radiotherapy. Seven cases showed recurrence: two with PR, four with STR, and one with GTR. Six cases received reoperation or radiotherapy after tumor progression, and one untreated patient died 5 months after tumor recurrence. The extent of tumor resection (HR 21.74, 95% CI 1.25-376.6, P = 0.03) and pathological grading (HR 131.99, 95% CI 4.05-4300.5, P = 0.006) were associated with improved OS. We presented our experience in the treatment of intracranial chondrosarcoma at three centers in the past 12 years. Intracranial chondrosarcoma lacked typical imaging features and are difficult to differentiate from other skull base lesions. Maximum extent of tumor resection with minimal injury to neurological function remains the most important treatment strategy. The extent of surgical resection and pathological grading were found to be predictors for OS.

A pregnant woman with a giant bilateral parietal hemangiopericytoma underwent multiple surgeries and radiotherapy: a case report and literature review.

Intracranial hemangiopericytoma is a rare invasive tumor originating from mesenchymal fibroblasts and is prone to local recurrence and distant metastasis. This study reports a case of a 27-year-old woman who presented with severe headache, nausea and vomiting for two weeks at thirty-three weeks of gestation. Cranial magnetic resonance imaging (MRI) demonstrated a giant lesion in the bilateral parietal lobe with a size of 5.12x9.19x6.03 cm and severe edema in the surrounding brain tissue. The patient underwent four operations and 3 gamma knife radiosurgery procedures and is recovering well now. The histopathology findings showed hemangiopericytoma and STAT6 and CD34 positivity after the first and second surgeries. Because of tumor progression, the patient received gamma knife radiosurgery at 1, 3, and 4 years after the first operation. Total tumor resection was achieved in the fourth surgery. Nevertheless, the patient showed malignant transformation to from low-grade to high-grade hemangiopericytoma.

Unruptured anterior Inferior cerebellar artery aneurysm following stereotactic irradiation for vestibular schwannoma: Case report and literature review.

Background: The clinical features and therapeutic measures of vestibular schwannoma (VS) radiation-related aneurysm (RRA) have not been well described. We reported the first VS RRA case admitted for acute anterior inferior cerebella artery (AICA) ischemic symptoms. Literature was reviewed to present the research fruits about VS RRAs, and some therapeutic advices were given. Materials and methods: A 54-year-old woman who had undergone GKS 10 years previously for a right VS was admitted to our hospital in 2018 because of sudden onset of severe vertigo and vomiting, accompanied with unsteady gait. During tumor resection, a dissecting aneurysm arose from the main trunk of AICA was encountered accidently within the tumor. The aneurysm was successfully treated with direct clip ligation, sparing the parent vessel. Data about this case were combined with those of other 11 radiation-related AICA aneurysm cases retrieved from the current literature. The following parameters were evaluated: Age, Sex, Diagnostic method, Location of aneurysm, Age of radiotherapy (Years)/Latency, Rupture, x-ray dosage, Type of radiotherapy, History of surgical resection of VS, Aneurysm Type, Morphology, Number, Treatment, Operative complications, Sequela, Outcome. VS RRAs mainly occurred in women (75%) with a median age of 62.5 years and were mainly located on AICA. Ruptured aneurysms accounted for 75.0% of the total cases. This paper reported the first VS case admitted with acute AICA ischemic symptoms. Cases with sacciform-like, irregular and fusiform-shaped aneurysms accounted for 50.0%, 25.0% and 25.0% of the total, respectively. After surgical treatment, 75.0% patients recovered, except for 3 patients who developed new ischemic consequence. Conclusion: Patients should be informed of the risk of RRAs after receiving radiotherapy for VS. In these patients, RRAs should be suspected when subarachnoid hemorrhage or AICA ischemic symptoms occurred. Active intervention should be conducted considering the high instability and bleeding rate of VS RRAs.

Knowledge structure and hotspots research of glioma immunotherapy: a bibliometric analysis.

Background: Glioma is the most common primary brain tumor. Traditional treatments for glioma include surgical resection, radiotherapy, chemotherapy, and bevacizumab therapy, but their efficacies are limited. Immunotherapy provides a new direction for glioma treatment. This study aimed to summarize the knowledge structure and research hotspots of glioma immunotherapy through a bibliometric analysis. Method: Publications pertaining to glioma immunotherapy published during the period from 1st January 1990 to 27th March 2023 were downloaded from the Web of Science Core Collection (WoSCC). Bibliometric analysis and visualization were performed using the CiteSpace, VOSviewer, Online Analysis Platform of Literature Metrology, and R software. The hotspots and prospects of glioma immunotherapy research were illustrated via analyzing the countries, institutions, journals, authors, citations and keywords of eligible publications. Results: A total of 1,929 publications pertaining to glioma immunotherapy in 502 journals were identified as of 27th March 2023, involving 9,505 authors from 1,988 institutions in 62 countries. Among them were 1,285 articles and 644 reviews. Most of publications were produced by the United States. JOURNAL OF NEURO-ONCOLOGY published the majority of publications pertaining to glioma immunotherapy. Among the authors, Lim M contributed the largest number of publications. Through analyzing keyword bursts and co-cited references, immune-checkpoint inhibitors (ICIs) were identified as the research focus and hotspot. Conclusion: Using a bibliometric analysis, this study provided the knowledge structure and research hotspots in glioma immunotherapy research during the past 33 years, with ICIs staying in the current and future hotspot. Our findings may direct the research of glioma immunotherapy in the future.

A Six-Surface System to Describe Anatomy of Anterior Clinoid Process and Its Application in Anterior Clinoidectomy and Resection of Paraclinoid Meningioma.

OBJECTIVE: The anterior clinoid process (ACP) is surrounded by nerves and vessels that, together, constitute an intricate anatomical structure with variations that challenges the performance of individualized anterior clinoidectomy in treating lesions with different extents of invasion. In the present study, we established a 6-surface system for the ACP based on anatomical landmarks and analyzed its value in guiding ACP drilling and resection of paraclinoid meningiomas. METHODS: Using the anatomical characteristics of 10 dry skull specimens, we set 9 anatomical landmarks to delineate the ACP into 6 surfaces. Guided by our 6-surface system and eggshell technique, 5 colored silicone-injected anatomical specimens were dissected via a frontotemporal craniotomy to perform anterior clinoidectomy. Next, 3 typical cases of paraclinoid meningioma were selected to determine the value of using our 6-surface system in tumor resection. RESULTS: Nine points (A-H and T) were proposed to delineate the ACP surface into frontal, temporal, optic nerve, internal carotid artery, cranial nerve III, and optic strut surfaces according to the adjacent tissues. Either intradurally or extradurally, the frontal and temporal surfaces could be identified and drilled into depth, followed by skeletonization of the optic nerve, cranial nerve III, internal carotid artery, and optic strut surfaces. After the residual bone was removed, the ACP was drilled off. In surgery of paraclinoid meningiomas, our 6-surface system provided great benefit in locating the dura, nerves, and vessels, thus, increasing the safety of opening the optic canal and relaxing the oculomotor or optic nerves and allowing for individualized ACP drilling for meningioma removal. CONCLUSIONS: Our 6-surface system adds much anatomical information to the classic Dolenc triangle and can help neurosurgeons, especially junior ones, to increase their understanding of the paraclinoid spatial structure and accomplish individualized surgical procedures with high safety and minimal invasiveness.

Construction and Application of Text Entity Relation Joint Extraction Model Based on Multi-Head Attention Neural Network.

Entity relationship extraction is one of the key areas of information extraction and is an important research content in the field of natural language processing. Based on past research, this paper proposes a combined extraction model based on a multi-headed attention neural network. Based on the BERT training model architecture, this paper extracts textual entities and relations tasks. At the same time, it integrates the naming entity feature, the terminology labeling characteristics, and the training relationship. The multi-attention mechanism and improved neural structures are added to the model to enhance the characteristic extraction capacity of the model. By studying the parameters of the multi-head attention mechanism, it is shown that the optimal parameters of the multi-head attention are h = 8, dv = 16, and the classification effect of the model is the best at this time. After experimental analysis, comparing the traditional text entity relationship extraction model and the multi-head attention neural network joint extraction model, the model entity relationship extraction effect was evaluated from the aspects of comprehensive evaluation index F1, accuracy rate P, and system time consumed. Experiments show: First, in the accuracy indicator, Xception performance is best, reaching 87.7%, indicating that the model extraction feature effect is enhanced. Second, with the increase of the number of iterative times, the verification set curve and the training set curve have increased to 96% and 98%, respectively, and the model has a strong generalization ability. Third, the model completes the extraction of all data in the test set in 1005 ms, which is an acceptable speed. Therefore, the model test results in this article are good, with a strong practical value.

Surgical Strategies and Outcomes for Intracranial Chondromas: A Retrospective Study of 17 Cases and Systematic Review.

Objective: To improve the diagnosis and treatment of intracranial chondromas (ICDs) by discussing the clinical manifestations and imaging characteristics of ICDs, as well as surgical methods and treatment strategies. Methods: We retrospectively analyzed 17 patients diagnosed with ICDs who underwent microsurgery or endoscopic transsphenoidal surgery at the Tangdu Hospital of Air Force Military Medical University and the Mianyang Central Hospital from January 2010 to November 2021. Clinical manifestations, imaging examinations, surgical treatments, and prognosis of these patients were analyzed. Results: ICDs had often been misdiagnosed as craniopharyngioma, chordoma, schwannoma, cavernous hemangioma, pituitary adenoma, and meningioma before surgery. Of the 17 cases, gross total resection (GTR) was performed in 10 cases, subtotal resection (STR) in 5, and partial resection in 2. GTR of tumor was achieved in eight cases via the endoscopic endonasal transsphenoidal approach (EETA) or the extended endoscopic endonasal transsphenoidal approach (EEETA), and the remaining patients underwent craniotomies. Clinical symptoms were assessed 1 week after surgery, 10 cases were relieved at varying degrees, and four cases had no improvement. Postoperative complications included right-limb hemiparesis, diplopia, eyelid ptosis, pulmonary infection, subcutaneous hydrops, cerebrospinal-fluid leakage (CSFL), and intracranial infection (ICI). One patient received gamma knife treatment at 3 months after surgery, two patients died due to tumor progression, and the remaining patients had no tumor recurrence. Conclusions: ICDs lack typical imaging features and are often misdiagnosed. The EETA or EEETA helps improve the surgical outcomes and GTR rates of ICDs at different sites.

Application of Subperineural Resection Technique in Vestibular Schwannomas: Surgical Efficacy and Outcomes in 124 patients.

Objective: We aimed to explore the application and prospects of the subperineural resection technique for tumor separation and removal under the perineurium during surgery for vestibular schwannomas (VSs). Methods: This study retrospectively analyzed 124 patients with VSs who underwent surgery via a retrosigmoid approach from July 2015 to October 2020 in the Department of Neurosurgery, Tangdu Hospital, Air Force Military Medical University. The data will be discussed with regard to the following aspects: clinical features, surgical strategies, tumor resection extent, facial-acoustic function preservation, and postoperative complications. Results: Gross total resection (GTR) of the tumor was achieved in 104 patients, with a GTR rate of 83.9%, and subtotal resection (STR) of the tumor was achieved in 20 patients. There was no significant difference in facial and acoustic nerve functional preservation between GTR and STR, as well as in tumor resection between solid and cystic tumors. The retention rate reached 97.6% in terms of complete anatomical facial nerve preservation. Facial nerve function was assessed using the House-Brackmann (HB) grading score. Consequently, HB grades of I-II, III-IV, and V-VI were determined for 96 (77.4%), 25 (20.2%), and 3 (2.4%) cases, respectively, 1 week postoperatively and accounted for 110 cases (88.7%), 13 cases (10.5%), and 1 case (0.8%), respectively, at 6 months. Fifteen of 35 (42.9%) patients with serviceable hearing before the operation still had serviceable hearing at 6 months postoperatively. There were 5 cases of cerebellar or brainstem bleeding after the operation, and one patient died. Multivariate logistic regression analysis showed that older age (≥60 years, p = 0.011), large tumor (>3 cm, p = 0.004), and cystic tumor (p = 0.046) were independent risk factors associated with the extent of adhesion between the tumor and the brainstem and facial-acoustic nerve. Conclusion: We successfully applied the subperineural resection technique to a large series of patients with VSs and achieved satisfactory results. Accurate identification of the perineurium and subperineural resection of the tumor can effectively reduce the disturbance of the facial-acoustic nerve during the operation and provide an intuitive basis for judging the tumor boundary. The subperineural resection technique may be conducive to improving the rate of total tumor resection and facial-acoustic nerve functional preservation in the surgical treatment of VSs.