Aneurysmoraphy or bypass? Surgical strategy for large M1 bifurcation aneurysm involving two branches based on vessel wall high-resolution MRI and intraoperative angiography.

BACKGROUND: Middle cerebral artery (MCA) M1 bifurcation aneurysms are common because of hemodynamic. For regular-shaped and small aneurysms, direct clipping is optimal. Aneurysmoraphy or bypass blood flow reconstruction are most commonly used in large aneurysm clipping. Based on preoperative vessel wall high-resolution magnetic resonance imaging (VW-HRMRI) and intraoperative angiography, an appropriate surgery strategy could be decided. METHOD: We report a case of large MCA M1 bifurcation aneurysm aneurysmoraphy according to preoperative VW-HRMRI. Intraoperative digital subtraction angiography (DSA) showed an aneurysm neck remnant, and we adjusted clips according to intraoperative DSA. This patient recovered well with a modified Rankin scale of 0 at discharge. CONCLUSION: This case demonstrates that preoperative VWHRMRI could supply more aneurysm characteristics for direct aneurysmoraphy. Intraoperative DSA effectively reduces the possibility of aneurysm remnant.

Initial experience of the treatment of large glioma with microwave ablation-assisted surgical resection.

Aim: This study aimed to investigate the preliminary clinical outcomes of microwave ablation (MWA)-assisted surgical treatment for large glioma. Materials and Methods: In total, six cases of large glioma (diameter >4 cm) were described. All cases were treated with MWA-assisted surgical resection, which was performed using ultrasound to guide the accurate placement of the antenna in the central region of the tumor. The MWA power was 40-45 W, and 6 min was applied. Changes in the ablation area were observed using intraoperative Doppler ultrasound and contrast-enhanced ultrasound (CEUS). Ten patients treated with surgical resection alone were included in the control group. Data on surgical times (i.e., the time from the incision of the dura to the removal of the tumor), intraoperative blood loss, and complications were recorded. Results: The median patient age was 45 years (range: 36.5-60.3 years). The median lesion diameter was 4.9 cm (range: 4.3-5.8). The microwave power was 40-45 W, and the median ablation time was 240 s (range: 208-297 s). The intra-tumoral vascular flow was significantly reduced after MWA. The median surgical time was shorter (38.5 min [range: 34.3-42.8 min]) and the median intraoperative blood loss was less (400 mL, [range: 400-450 mL]) in the combination treatment group than in the surgery-alone group. During the ablation process, no obvious additional neurological deficits were detected; however, a tube-shaped carbonide was found after the operation. Conclusion: MWA may be a useful complement to conventional techniques for the surgical resection of large glioma.

The comparison of the watertight and non-watertight dural closure in supratentorial craniotomy: A single-institute 10-year experience with 698 patients.

Watertight dural closure (WTDC) is considered crucial by many neurosurgeons in cranial base surgery, infratentorial craniotomy, and spinal intradural procedure. Whether WTDC also reduce complications remains controversial in supratentorial craniotomy. The objective of this study is to investigate the relationship between WTDC and CSF-related complications in supratentorial craniotomy for the resection of space-occupying lesions. A retrospective analysis of patients who suffered from intracranial space-occupying lesions at Beijing Ditan Hospital between January 2011 and December 2021 was conducted. A total of 698 cases were reviewed with attention to the operative approach, subgaleal fluid collection, wound healing impairment, postoperative infection, and post-craniotomy headaches. The study included a total of 423 patients with WTDC and 275 patients without WTDC. Patients without WTDC had a significantly higher rate of infection (10.9% vs 4.5% with WTDC, P = .001). The rate of subgaleal fluid collection was 9.7% in the WTDC group and 11.3% in the non-WTDC group, but this difference was not statistically significant (P = .502). They suffered from a greater incidence of post-craniotomy headaches in the WTDC group (13.5% vs 9.5% in the non-WTDC group), but without statistical significance (P = .109). We also found no difference in wound healing impairment (P = .719). There is less postoperative infection associated with WTDC during intracranial space-occupying lesion removal than without WTDC in supratentorial craniotomy.

How I do it? Basilar bifurcation and left anterior choroidal artery aneurysms clipping.

BACKGROUND: Despite advancements in endovascular techniques, microsurgical treatment for posterior circulation aneurysms remains challenging. METHOD: This report highlights the successful clipping surgery of a 17-year-old female patient with an aneurysm located at the basilar artery (BA) bifurcation and left anterior choroidal artery (AChoA). To improve exposure, the posterior communicating artery was transected. A straight fenestrated clip was then placed to repair the BA bifurcation aneurysm, followed by a curved mini clip for the AChoA aneurysm. CONCLUSION: This report demonstrates the nuances of microsurgery in the treatment of select complex cases, which can benefit from microsurgery to achieve optimal treatment outcomes.

Identification and gene expression profiling of human gonadotrophic pituitary adenoma stem cells.

BACKGROUND: Gonadotrophic pituitary adenoma is a major subtype of pituitary adenoma in the sellar region, but it is rarely involved in the hypersecretion of hormones into blood; thus, it is commonly regarded as "non-functioning." Its tumorigenic mechanisms remain unknown. The aim of this study was to identify human gonadotrophic pituitary adenoma stem cells (hPASCs) and explore the underlying gene expression profiles. In addition, the potential candidate genes involved in the invasive properties of pituitary adenoma were examined. METHODS: The hPASCs from 14 human gonadotrophic pituitary adenoma clinical samples were cultured and verified via immunohistochemistry. Genetic profiling of hPASCs and the matched tumor cells was performed through RNA-sequencing and subjected to enrichment analysis. By aligning the results with public databases, the candidate genes were screened and examined in invasive and non-invasive gonadotrophic pituitary adenomas using Real-time polymerase chain reaction. RESULTS: The hPASCs were successfully isolated and cultured from gonadotrophic pituitary adenoma in vitro, which were identified as positive for generic stem cell markers (Sox2, Oct4, Nestin and CD133) via immunohistochemical staining. The hPASCs could differentiate into the tumor cells expressing follicle-stimulating hormone in the presence of fetal bovine serum in the culture medium. Through RNA-sequencing, 1352 differentially expressed genes were screened and identified significantly enriched in various gene ontologies and important pathways. The expression levels of ANXA2, PMAIP1, SPRY2, C2CD4A, APOD, FGF14 and FKBP10 were significantly upregulated while FNDC5 and MAP3K4 were downregulated in the invasive gonadotrophic pituitary adenomas compared to the non-invasive ones. CONCLUSION: Genetic profiling of hPASCs may explain the tumorigenesis and invasiveness of gonadotrophic pituitary adenoma. ANXA2 may serve as a potential therapeutic target for the treatment of gonadotrophic pituitary adenoma.

Treatment of high-grade brain arteriovenous malformations using a hybrid operating room: A prospective single-arm study.

BACKGROUND: Optimal treatment of patients with high Spetzler-Martin (S-M) grade brain arteriovenous malformations (BAVMs) remains controversial. Few studies have investigated outcomes in such patients treated in a hybrid operating room (hOR). OBJECTIVE: To examine outcomes of one-stop hybrid BAVM treatment in patients with high-grade lesions. METHODS: We prospectively enrolled patients with high-grade BAVMs (S-M grade ≥3) aged 18-65 years who underwent one-stop hybrid BAVM treatment at our hospital between October 2016 and March 2021. High-grade BAVM patients who underwent surgery from 2010 to 2016 served as historical controls. RESULTS: Forty-one high-grade BAVM patients underwent one-stop hybrid treatment in a hOR. Sixty-one propensity score-matched patients comprised the historical control group. The groups did not significantly differ in patient and BAVM characteristics. Intraoperative angiography in four patients of the hOR group demonstrated residual nidus that required further immediate resection. Main procedural complications included hemorrhage, neurologic deficit, and seizure. In the historical control group, diffuse angioarchitecture and arteriovenous fistula were independent risk factors for incomplete resection. CONCLUSIONS: One-stop hybrid BAVM treatment is safe and effective for removal of high-grade BAVMs, especially those with diffuse or complex angioarchitecture. Preoperative embolization can effectively reduce blood flow while preserving motor and language function. The combined application of functional magnetic resonance imaging, electrophysiological monitoring, and awake craniotomy can successfully avoid causing neurological injury.

Diagnostic value of EBV-DNA in CSF for PCNSL in AIDS patients with focal brain lesions: A meta-analysis of diagnostic test.

BACKGROUND: Epstein-Barr virus (EBV) infection plays a crucial role in the progression of acquired immunodeficiency syndrome related primary central nervous system lymphoma (AR-PCNSL). This study aimed at evaluating the diagnostic value of cerebrospinal spinal fluid (CSF) EBV-deoxyribonucleic acid (DNA) for PCNSL in patients with infection of human immunodeficiency (HIV) virus through a meta-analysis of diagnostic test. METHODS: A systematic search in PubMed, Embase, Web of Science, Wanfang, Chinese Biomedical Database and Chinese National Knowledge Infrastructure was conducted before May 10, 2022. Heterogeneity among the studies was assessed using Q test and I2 statistics. Publication bias was assessed using the Deek's funnel plot asymmetry test. Statistical analyses were performed using Stata 16.0 software. The pooled sensitivity, specificity, positive and negative likelihood ratios (PLR and NLR), diagnostic odds ratios (DOR) and 95% confidence intervals (CI) were caculated to evaluate the diagnostic value. A symmetric receiver operating characteristic (SROC) curve and the area under the SROC curve (AUC) were constructed to evaluate the test-performance. RESULTS: Twelve studies were included in the final analyses, with a total of 141 patients with AR-PCNSL and 590 controls. The pooled diagnostic values were sensitivity of 0.83 (95% CI: 0.73-0.90), specificity of 0.95 (95%CI: 0.89-0.98), PLR of 17.8 (95%CI: 6.8-46.1), NLR of 0.17 (95%CI: 0.10-0.30), DOR of 102 (95%CI: 28-379), and AUC of 0.94 (95%CI: 0.91-0.96). CONCLUSION: In summary the overall diagnostic value of CSF EBV-DNA is very high and it can be a reliable diagnostic biomarker for AR-PCNSL.

Consistency of pituitary adenomas: Amounts of collagen types I and III and the predictive value of T2WI MRI.

Pituitary adenomas, the most common type of lesion in the sellar region, rank third among all brain tumors, with an incidence of 73-94 cases per 100,000 individuals. Due to its high resolution, MRI is highly efficient in brain imaging and has emerged as the most appropriate method for tumor consistency evaluation. The present study aimed to assess the levels of collagen types I and III in pituitary adenomas with different consistencies and to determine the value of T2-weighted imaging (T2WI) MRI for predicting tumor consistency. A total of 55 patients with pituitary adenomas were divided into the soft and firm tumor groups according to intraoperative tumor consistency. The ratio of the tumor to Pons' signal intensities on T2WI scans was determined. A receiver operating characteristic curve was plotted to assess the specificity and sensitivity of T2WI in predicting tumor consistency. Average optical density (AOD) values for collagen types I (0.046±0.008 vs. 0.052±0.012, P=0.033) and III (0.044±0.008 vs. 0.050±0.010, P=0.016) were significantly lower in the soft tumor group compared with those in the firm tumor group. There was no significant difference in the ratio of the tumor to Pons' signal intensities on T2WI scans. The area under the ROC curve was 0.595±0.078 (P=0.250). The maximum tumor diameter significantly differed between the soft and firm tumor groups (P=0.001). AOD values for collagen types I and III were significantly correlated with the maximum tumor diameter (P<0.001). The amounts of collagen types I and III were elevated in firm pituitary tumors compared with the soft ones. The ratio of tumor to Pons' signal intensities on T2WI scans was not able to accurately predict tumor consistency. The size of pituitary adenomas may be associated with the expression levels of collagen types I and III.

Microsurgical intracranial hypervascular tumor resection immediately after endovascular embolization in a hybrid operative suite: A single-center experience.

BACKGROUND: This study was performed to investigate the safety and outcome of one-stage hybrid endovascular and microsurgical treatment of intracranial hypervascular tumors. METHODS: The blood supply of the tumor was endovascularly embolized just before microsurgery in a one-stage fashion. Clinical data regarding the preoperative neurological status, tumor characteristics, hybrid treatment details and complications, intraoperative blood loss, and postoperative outcomes were collected prospectively and then analyzed. RESULTS: Beginning in July 2016, 13 patients (5 women, 8 men) with intracranial hypervascular tumors were enrolled in this study, with a mean age of 48.2 ± 10.9 years. The patients' tumors comprised seven hemangioblastomas, three hemangiopericytomas, two meningiomas, and one mesenchymal chondrosarcoma. The mean maximum tumor diameter was 54.9 ± 21.5 mm. No major procedural complications occurred except catheterization-related bleeding in one patient. The mean percentage of tumor devascularization was 65.0%±17.5%. Gross total resection was achieved in 12 patients (92.3%). The mean blood loss volume during microsurgical resection was 703.8 ± 886.8 mL (range, 150-3600 mL). Symptoms improved in three patients and remained stable in six patients. CONCLUSIONS: One-stage hybrid embolization before intracranial hypervascular tumor resection is a safe and effective procedure to decrease intraoperative blood loss. It can prevent or treat embolization-related complications in a timely manner and avoid the risk of multiple surgical procedures.

MicroRNA-935 Directly Targets FZD6 to Inhibit the Proliferation of Human Glioblastoma and Correlate to Glioma Malignancy and Prognosis.

MicroRNAs (miRNAs) are involved in human glioblastoma (GB). MiR-935 has been reported to have both tumor-inhibiting and tumorigenesis effects, but its role in GB remains unclear. Because of the high mortality and morbidity associated with the malignancy of GB, a deeper understanding of the molecular crosstalk that occurs in GB is needed to identify new potential targets for treatment. At present, the mechanism of GB at the molecular level is not fully understood. With the aid of bioinformatic analysis, miR-935 was significantly downregulated in GB, and it presented a poorer outcome. In the glioma cell line and in the nude mice model, the miR-935 inhibited cell proliferation by modulating cell circles in vitro and in vivo. Then, the target genes of miR-935 were analyzed by using the online database, and the direct binding was tested with a luciferase analysis. FZD6 was found to be the direct target of miR-935. The effect of miR-935 was recovered by the overexpression of FZD6 in vitro. In addition, the negative correlation of miR-935 and the expression of FZD6 were confirmed in our clinical samples, and the expression of FZD6 has a strong correlation with tumor malignancy and prognosis. This study showed that miR-935 directly inhibited the expression of FZD6 and inhibited the cell proliferation, thereby suppressing the development of GB, suggesting that miR-935 is a cancer suppressor miRNA and may become a prognostic biomarker or a promising potential therapeutic target for human GBs.

Targeted exome sequencing for the identification of common mutational signatures and potential driver mutations for brain metastases and prognosis.

Brain metastases (BMs) are malignancies in the central nervous system with poor prognosis. Genetic landscapes of the primary tumor sites have been extensively profiled; however, mutations associated with BMs are poorly understood. In the present study, target exome sequencing of 560 cancer-associated genes in samples from 52 patients with brain metastasis from various primary sites was performed. Recurrent mutations for BMs from distinct origins were identified. There were both genetic homogeneity and heterogeneity between BMs and primary lung tumor tissues. The mutation rate of the major cancer driver gene, TP53, was consistently high in both the primary lung cancer sites and BMs, while some genetic alterations, associated with DNA damage response deficiency, were specifically enriched in BMs. The mutational signatures enriched in BMs could serve as actionable targets for treatment. The mutation in the primary site of the potential brain metastasis driver gene, nuclear mitotic apparatus protein 1 (NUMA1), affected the progression-free survival time of patients with lung cancer, and patients with the NUMA1 mutation in BMs had a good prognosis. This suggested that the occurrence and clinical outcome of brain metastases could be independent of each other.

One-Stage Treatment in a Hybrid Operation Room to Cure Brain Arteriovenous Malformation: A Single-Center Experience.

OBJECTIVE: To report the principles and techniques of using a hybrid operation room in the treatment of brain arteriovenous malformation (BAVM). METHODS: From October 1, 2016 to December 31, 2018, we treated 54 consecutive patients with nonemergent BAVM in a hybrid operation room. The clinical data, radiologic images, and outcomes were collected to establish a prospective database for evaluation. RESULTS: Thirty-two male and 22 female patients were enrolled with a mean age of 32.6 ± 13.1 years (range, 10-61 years). Bleeding (n = 32, 59.3%) was the main clinical presentation, followed by headache (n = 27, 50.0%), seizures (n = 14, 25.9%), neurofunctional deficits (n = 16, 29.6%), and no symptoms (n = 2, 3.7%). Thirty-one patients (57.4%) accepted resection without intraoperative embolization, 18 (33.3%) were treated with combined embolization and resection, and 5 (9.3%) were cured with intraoperative embolization and resection was cancelled. All patients achieved total BAVM obliteration confirmed with intraoperative angiography. There were no significant differences in outcomes between low-grade (Spetzler-Martin grades I, II, and modified grade III-) and high-grade (Spetzler-Martin grades ≥IV and modified grade III+) groups, except that the high-grade group had more blood loss (667.9 ± 647.5 vs. 284.3 ± 148.6 mL; P = 0.046) and longer postoperative hospitalization (17.1 ± 9.1 vs. 10.8 ± 5.4 days; P = 0.026). At discharge, 52 patients (96.3%) had favorable outcomes (Glasgow Outcome Scale score ≥4). Forty-three patients (79.6%) received 1 year follow-up after treatment; 97.7% (n = 42) of these had ongoing favorable outcomes. However, 4 patients with low-grade BAVM had recurrence. CONCLUSIONS: The hybrid operation room can ensure safe, comprehensive treatment of BAVM, offering the opportunity for a favorable curative treatment in 1 stage.

DZIP3 is a key factor to stratify IDH1 wild-type lower-grade gliomas.

BACKGROUND: Malignant glioma is the most common form of primary malignant brain cancer. Heterogeneity is the hallmark of glioma. DAZ-interacting zinc finger 3 (DZIP3), acts as an RNA-binding RING-type ubiquitin ligase; however, its function in glioma is yet unclear. RESULTS: The DZIP3 expression was related to the World Health Organization (WHO) grade and isocitrate dehydrogenase 1(IDH1) status, as well as the clinical outcome. Malignant cases exhibit lower DZIP3 expression. DZIP3 was an independent predictive factor of good prognosis in all grade and lower grade gliomas (p < 0.0001). Gene enrichment analysis and immunohistochemistry indicated that DZIP3 affected the biological behavior of glioma through the angiogenesis pathway. Moreover, based on DZIP3 expression, IDH1 wild-type lower-grade gliomas could be divided into two groups with different survival time. CONCLUSION: In conclusion, the loss of DZIP3 may be involved in the mechanism of angiogenesis in the invasive biological process of glioma. These findings laid an understanding of DZIP3-specific clinical features in glioma. METHODS: A total of 325 glioma patients from the Chinese Glioma Genome Atlas (CGGA) RNA-seq cohort comprised the training cohort, while 265 patients from the GSE 16011 array cohort formed the validation cohort. The mRNA expression of DZIP3 and clinical characteristics was assessed. DZIP3 protein expression and microvessel density (MVD) were evaluated by immunohistochemistry (IHC).

Comprehensive analysis of the immunological landscape of pituitary adenomas: implications of immunotherapy for pituitary adenomas.

PURPOSES: Immunotherapies for solid tumor are gaining traction in the clinic, however, the immunological landscape of pituitary adenomas (PAs) is not well defined. In the present study, we used the RNA-seq data of PAs to investigate the impact of immunological landscape on clinical features of pituitary adenomas and aim to evaluate the potential immunotherapy for PAs. METHODS: We analyzed tumor-infiltrating immune cells in 115 PA samples using RNA-seq. Main immune cell types (B cells, CD8+ T cells, CD4+ T cells, macrophages and NK cells) were detected from the expression of genes. The association between immune cells abundance and immune checkpoint, as well as inflammatory factors were analyzed. 10 additional patients were enrolled for validation. RESULTS: In RNA sequencing data, landscape of PAs were identified. Our computationally inferred immune infiltrates significantly associate with patient clinical features. Growth hormone-secreting adenomas (GHomas) were found with higher B cells and CD8+ T cells infiltration. Moreover, GHomas showed relative different genetic background, significant invasive behavior and independently correlated with reduced progress-free time. Tumor progression was related to increased expression of PD-1/PD-L1 and was associated with higher immune infiltration. Analysis of cancer-testis antigen expression and CD8+ T-cell abundance suggested CTAG2 and TSPYL6 were potential immunotherapeutic targets in GHomas and non-functioning adenomas, respectively. CONCLUSIONS: Tumor-infiltrating immune cells confer important clinical and biological implications. Our results of immune-infiltrate levels in PAs may inform effective cancer vaccine and checkpoint blockade therapies and make it possible to take immunotherapy into invasive PAs.

Clinical Characteristics and Surgical Features of Intracranial Fibrosarcoma.

BACKGROUND: Intracranial fibrosarcoma is an extremely rare neoplasm in the central nervous system. Insofar there were only sporadic case reports describing its features. The purpose of this study is to review the clinical and surgical features of cases who were treated in our department. METHOD: The authors retrospectively reviewed and detailed the clinical and surgical data obtained from 5 patients with fibrosarcoma who underwent treatment at our institute between January 2009 and January 2019. RESULTS: There were 3 males and 2 females including 2 juvenile and 3 senior patients. The most frequent sign was intermittent pain and vomiting. The location of the tumor included middle fossa, thalamus and midbrain, sellar and suprasellar region and right parietal-occipital lobe. Surgical observation demonstrated the consistency of the tumor was tenacious with abundant blood supply. Gross total resection was achieved in 2 cases. Pathological analysis showed spindle cells in a herringbone form with positive Vimentin staining in all 5 cases, with the absence of GFAP or S-100. All 5 patients were deceased eventually after a varied period of time after the first surgery. CONCLUSION: Intracranial fibrosarcoma was a highly malignant entity presented in the central nervous system. Surgery still remains the first-line treatment followed by radiotherapy, however, the prognostic outcome was very poor. Future studies should be more focused on accumulation of the relevant information on this disease thus hopefully in assisting to developing more optimized treatment.

Identification of a Glycolysis-Related LncRNA Signature to Predict Survival in Diffuse Glioma Patients.

Glycolysis refers to one of the critical phenotypes of tumor cells, regulating tumor cell phenotypes and generating sufficient energy for glioma cells. A range of noticeable genes [such as isocitrate dehydrogenase (IDH), phosphatase, and tensin homolog (PTEN), or Ras] overall impact cell proliferation, invasion, cell cycle, and metastasis through glycolysis. Moreover, long non-coding RNAs (LncRNAs) are increasingly critical to disease progression. Accordingly, this study aimed to identify whether glycolysis-related LncRNAs have potential prognostic value for glioma patients. First, co-expression network between glycolysis-related protein-coding RNAs and LncRNAs was established according to Pearson correlation (Filter: |r| > 0.5 & P < 0.001). Furthermore, based on univariate Cox regression, the Least Absolute Shrinkage and Selection Operator (LASSO) analysis and multivariate Cox regression, a predictive model were built; vital glycolysis-related LncRNAs were identified; the risk score of every single patient was calculated. Moreover, receiver operating characteristic (ROC) curve analysis, gene set enrichment analysis (GSEA), GO and KEGG enrichment analysis were performed to assess the effect of risk score among glioma patients. 685 cases (including RNA sequences and clinical information) from two different cohorts of the Chinese Glioma Genome Atlas (CGGA) database were acquired. Based on the mentioned methods, the risk score calculation formula was yielded as follows: Risk score = (0.19 × EXPFOXD2-AS1) + (-0.27 × EXPAC062021.1) + (-0.16 × EXPAF131216.5) + (-0.05 × EXPLINC00844) + (0.11 × EXPCRNDE) + (0.35 × EXPLINC00665). The risk score was independently related to prognosis, and every single mentioned LncRNAs was significantly related to the overall survival of patients. Moreover, functional enrichment analysis indicated that the biologic process of the high-risk score was mainly involved in the cell cycle and DNA replication signaling pathway. This study confirmed that glycolysis-related LncRNAs significantly impact poor prognosis and short overall survival and may act as therapeutic targets in the future.

Brainstem Tumor Resection via Occipital Interhemispheric Transtentorial Infracollicular Approach: 2-Dimensional Operative Video.

A brainstem tumor located at the upper pons or pontomesencephalic region is surgically challenging because of the deep-seated location and difficulty to approach, especially if the lesion is intra-axial and extends anteriorly without appearing on the pia surface. In our experience, the infracollicular entry point is feasible for such lesions and can be approached by an occipital interhemispheric transtentorial corridor through a straightforward trajectory, which ensures surgical ergonomics. Herein, we present a case of a 55-yr-old woman with a pontomesencephalic lesion removed via an occipital interhemispheric transtentorial infracollicular approach. Informed consent was obtained from the patient. Her preoperative medical course and radiological findings strongly indicated the lesion as a brainstem cavernous malformation. Although the overlying brainstem parenchyma was thin, the lesion did not appear on the pial surface. The lesion was removed via an occipital interhemispheric transtentorial infracollicular approach. During the operation, the lesion was observed to have an old hemorrhagic component and an obvious gliotic boundary, resembling the typical macropathology of a brainstem cavernous malformation. We easily dissected the lesion circumferentially off the brainstem parenchyma after thorough debulking, and a gross total resection was performed en bloc. However, postoperative pathology confirmed a diagnosis of a metastatic neuroendocrine tumor, and further systematic examination revealed cancerous lesions in the lungs. The patient experienced slight hypophrasia but recovered within 3 d postoperatively and then was discharged for further treatment. This case demonstrates the safety and efficacy of an occipital interhemispheric transtentorial infracollicular approach for brainstem tumor resection.

Gravity-Assisted Ipsilateral Paramedian Approach for Parafalcine Meningioma Resection.

BACKGROUND: In our series, the gravity-assisted ipsilateral paramedian approach was shown to be safe and advantageous for the resection of parafalcine meningioma, because it does not result in contralateral brain impingement and does not require brain retraction. We have reported the technical details of this method and the outcomes of our patients. METHODS: From September 2018 to September 2019, 10 consecutive patients with parafalcine meningioma underwent microsurgery using the gravity-assisted ipsilateral paramedian approach. The clinical data, radiological images, and surgical outcomes were collected and analyzed. RESULTS: All 10 patients (5 men and 5 women, mean age, 55.8 ± 12.5 years) underwent safe tumor resection. Of the 10 tumors, 6 were located in the frontal area, 2 in the parietal area, and 2 in frontal and parietal area. The superior sagittal sinus wall had been affected in 6 patients. Obvious perilesional edema was observed in 60% of the patients. During surgery, bridging veins were encountered in 8 patients and were preserved, except for a small branch. Brain retraction or transgression was not required, and gross total resection was achieved in all 10 patients. No major postoperative complications occurred, except for an unexpected subacute subdural hematoma 1 month postoperatively. All 10 patients had achieved a favorable outcome (Glasgow outcome scale, ≥ 4) at discharge, which remained the same after a mean follow-up of 5.8 ± 3.7 months. CONCLUSIONS: The results from the present case series have demonstrated the safety of the gravity-assisted ipsilateral paramedian approach for parafalcine meningioma resection. The approach provides good tumor exposure and clear identification and preservation of bridging veins, does not result in contralateral brain impingement, and does not require excessive brain retraction.

Pure Endoscopic Surgery via Subtemporal Extradural Keyhole Approach for Middle Cranial Fossa Tumors.

OBJECTIVE: Extradural subtemporal keyhole approach could provide adequate removal for some specific middle skull base tumors. The combination of endoscopy and keyhole technique might further help to minimize the complications and provide optimal surgical visualization. Here, a series of attempts with endoscopy by mini-invasive subtemporal extradural approach for 5 middle skull base tumors were successfully achieved. METHODS: From November 2015 to November 2018, resections of 5 cases of middle cranial fossa tumors were performed with pure endoscopy via subtemporal extradural keyhole approach. Patient medical records, imaging data, surgical procedures, pathology results, and follow-up outcomes were collected and analyzed. RESULTS: Adequate extradural subtemporal space was successfully established for endoscopy, and tumor resection was performed. Postoperative pathology confirmed cholesteatoma, cholesterol granuloma, schwannoma, granuloma, and osteoblastoma, respectively. Two patients with osteoblastoma and granuloma received subtotal resection, and the other 3 achieved total resection. One patient suffered from brain edema and was relieved after systematic mannitol treatment. No other complications were observed, and no progression was found during follow-up. CONCLUSIONS: This exploratory series demonstrated the safety and effectiveness of pure endoscopic surgery via subtemporal extradural route for satisfactory middle cranial base tumor resection.

YKL-40 can promote angiogenesis in sporadic cerebral cavernous malformation (CCM).

The factors affecting the formation of sporadic CCMs remain unclear. A cDNA microarray was used to identify characteristic gene expression patterns in sporadic CCMs. Transcription level of YKL-40 was confirmed by reverse transcription-polymerase chain reaction (RT-PCR). The location and expression were revealed by immunochemistry, immunofluorescence staining and level of YKL-40 was quantified by Western blotting. Alterations to endothelial function following the up or down regulation of gene expression was assessed by Transwell assays, cell counting kit-8 assays and capillary-like tube formation assays in human brain microvascular endothelial cells (HBMECs) in vitro. We generated a murine model by stereotaxically injecting HBMECs with expressing amounts of YKL-40 into the brain. cDNA microarray and RT-PCR results revealed that the transcription level of YKL-40 was ≥140-fold higher in sporadic CCMs in healthy controls. Histological staining revealed excessive YKL-40 expression in the CCM endothelium. Western blotting results analysis showed that YKL-40 protein expression was significantly higher in CCM endothelium (P < 0.05). YKL-40 over-expressing HBMECs showed increased cell proliferation, migration and tube formation ability compared with the control group, whereas downregulating of YKL-40 inhibited the proliferation, migration of HBMECs and capillary-like tube formation (P < 0.05). In animals, increased of YKL-40 was associated with abnormal vascular lesions that were similar to CCMs. YKL-40 is over-expressed in the CCM endothelium and acts as an angiogenic factor that promotes the pathogenesis of sporadic CCMs. YKL-40 may therefore represent a potential therapeutic target in the treatment of sporadic CCM.