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Background The aim of this study is to address the paucity of epidemiological data regarding the characteristics, treatment patterns and survival outcomes of Chinese glioblastoma patients. Methods This was a population-level study of Hong Kong adult (>18 years) Chinese patients with newly diagnosed histologically confirmed glioblastoma between 2006 and 2019. The age standardized incidence rate (ASIR), patient-, tumor- treatment-related characteristics, overall survival (OS) as well as its predictors were determined. Results One thousand and ten patients with a median follow-up of 10.0 months were reviewed. The ASIR of glioblastoma was 1.0 per 100 000 population with no significant change during the study period. The mean age was 57 + 14 years. The median OS was 10.6 months (IQR: 5.2–18.4). Independent predictors for survival were: Karnofsky performance score >80 (adjusted OR: 0.8; 95% CI: 0.6–0.9), IDH-1 mutant (aOR: 0.7; 95% CI: 0.5–0.9) or MGMT methylated (aOR: 0.7; 95% CI: 0.5–0.8) glioblastomas, gross total resection (aOR: 0.8; 95% CI: 0.5–0.8) and temozolomide chemoradiotherapy (aOR 0.4; 95% CI: 0.3–0.6). Despite the significant increased administration of temozolomide chemoradiotherapy from 39% (127/326) of patients in 2006–2010 to 63% (227/356) in 2015–2019 (P-value < .001), median OS did not improve (2006–2010: 10.3 months vs 2015–2019: 11.8 months) (OR: 1.1; 95% CI: 0.9–1.3). Conclusions The incidence of glioblastoma in the Chinese general population is low. We charted the development of neuro-oncological care of glioblastoma patients in Hong Kong during the temozolomide era. Although there was an increased adoption of temozolomide chemoradiotherapy, a corresponding improvement in survival was not observed.

Meningiomas are the most common primary intracranial tumors. There are no effective medical therapies for meningioma patients, and new treatments have been encumbered by limited understanding of meningioma biology. Here, we use DNA methylation profiling on 565 meningiomas integrated with genetic, transcriptomic, biochemical, proteomic and single-cell approaches to show meningiomas are composed of three DNA methylation groups with distinct clinical outcomes, biological drivers and therapeutic vulnerabilities. Merlin-intact meningiomas (34%) have the best outcomes and are distinguished by NF2/Merlin regulation of susceptibility to cytotoxic therapy. Immune-enriched meningiomas (38%) have intermediate outcomes and are distinguished by immune infiltration, HLA expression and lymphatic vessels. Hypermitotic meningiomas (28%) have the worst outcomes and are distinguished by convergent genetic and epigenetic mechanisms driving the cell cycle and resistance to cytotoxic therapy. To translate these findings into clinical practice, we show cytostatic cell cycle inhibitors attenuate meningioma growth in cell culture, organoids, xenografts and patients.

Myoepithelial tumors are rare neoplasms that develop from myoepithelial cells in glandular structures and soft tissues. Primary intracranial myoepithelial neoplasms are even rarer with around ten cases reported. On the other hand, adrenocortical carcinoma (ACC) is also uncommon with an annual incidence of 0.7–2 per million and carries a poor prognosis. It is known to have an association with certain familial cancer syndromes. Even in sporadic cases, a significant portion of them had other malignancies before and after diagnosis of ACC. We reported a 34-year-old gentleman who was diagnosed to have ACC without known familial cancer syndrome. After that, he was also found to have right occipital myoepithelioma that was confirmed by excisional biopsy. There was no known association between these two pathologies. This is the first report of coincidence of ACC and intracranial myoepithelioma.

Gamma Knife radiosurgery (GKRS) is a frequent treatment choice for patients with small- to moderate-sized vestibular schwannoma (VS). However, pseudoprogression after GKRS is commonly observed, with a reported incidence ranging from 7% to 77%. The wide range of the reported incidence of pseudoprogression reflects the fact that there is no consensus on how it should be diagnosed. The authors present the case of a 66-year-old woman who had a 2.5-cm right-sided VS treated with GKRS in 1997. The first posttreatment MRI obtained 5 months later showed that the tumor volume had increased to 9.7 cm3. The tumor volume increased further and reached its peak 24 months after treatment at 20.9 cm3, which was a 161% increase from pretreatment volume. Thereafter, the tumor shrank gradually and mass effect on the brainstem reduced over time. By 229 months after treatment, the tumor volume was 1.0 cm3, equaling 12.5% of pretreatment tumor volume, or 4.8% of peak tumor volume after treatment. This case demonstrates that if a patient remains asymptomatic despite a dramatic increase in tumor volume after GKRS, observation remains an option, because even a very sizable tumor can shrink with near-complete resolution. Patients undergoing GKRS for VS should be counseled regarding the possibility of pseudoprogression, and followed carefully over time while avoiding premature decisions for surgical removal after treatment.

Background Facial paresis is one of the complications after treatment for vestibular schwannoma (VS). Acupuncture has been used for Bell palsy but not in iatrogenic facial paresis. The objective of this study is to measure the efficacy of using acupuncture for iatrogenic facial nerve palsy and patients' satisfaction. Methods This is a single-center retrospective study with patients from 2007–2019 received treatment for newly diagnosed or recurrent VS. Some patients who suffered facial paresis after surgery had self-initiated acupuncture. All patients who had facial paresis were included. Their facial nerve status before and immediately after surgery, postoperative 6 months and 12 months, were recorded. Those who received acupuncture also answered 6- and 12-month patient satisfaction surveys over the phone. Adverse effects were also assessed. Results There were 123 patients in this period. Of these, 29 patients had iatrogenic facial paresis and 23 of them received acupuncture. There was significant improvement of facial paresis for the acupuncture group compared with the nonacupuncture group at 6 and 12 months. More than 80% of patients who received acupuncture were satisfied. They had motor improvement and experienced less pain and tightness. No adverse effects were reported. Conclusions Acupuncture for postresection VS facial paresis seemed to speed up its recovery. Both patients' recovery and satisfaction were good after acupuncture, and it seemed to be a safe procedure in trained hands.

BACKGROUND Surgical treatment of intrathoracic meningoceles, commonly associated with neurofibromatosis type 1 (NF1), aims to reduce sac size for symptomatic relief. The procedures can be divided into cerebrospinal fluid diversion and definitive repair. The authors describe the management of an intrathoracic meningocele in a 56-year-old female with preexisting NF1. OBSERVATIONS The patient presented with progressive dyspnea. Magnetic resonance imaging revealed a left hemithoracic meningocele arising from the thecal sac at C7–T2. Two attempts at diversion by cystoperitoneal shunts resulted in recurrence. For definitive repair, T2–3 costotransversectomy was performed, and intradural closure of the meningocele opening was performed utilizing spinal dura and autologous fascia lata graft. Trapezius muscle regional flap was turned for reinforcement. Persistent leak warranted reoperation 7 days later. A transthoracic approach was undertaken using video-assisted thoracoscopic resection of the sac at aortic arch level, with reinforcement by latissimus dorsi flap and synthetic materials. Mechanical pleurodesis was performed. Intradural repair of the meningocele opening was revised. LESSONS Inherent dural abnormality makes repair difficult for meningoceles associated with NF1. A combined intradural and thoracoscopic approach with regional muscle flap and synthetic material reinforcement is a unique method for definitive treatment. Some essential points of perioperative management are highlighted.

// Peter Y.M. Woo 1 , Tai-Chung Lam 2 , Jenny K.S. Pu 3 , Lai-Fung Li 3 , Roland C.Y. Leung 4 , Jason M.K. Ho 1 , James T.F. Zhung 5 , Belinda Wong 6 , Timonthy S.K. Chan 7 , Herbert H.F. Loong 8 and Ho-Keung Ng 9 1 Department of Neurosurgery, Kwong Wah Hospital, Hong Kong 2 Department of Clinical Oncology, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Hong Kong 3 Department of Neurosurgery, Queen Mary Hospital, Hong Kong 4 Department of Medicine, Queen Mary Hospital, Hong Kong 5 Department of Neurosurgery, Kwong Wah Hospital, Hong Kong 6 Pharmacy and Medical Therapeutics, Kwong Wah Hospital, Hong Kong 7 Department of Pathology, Kwong Wah Hospital, Hong Kong 8 Department of Clinical Oncology, The Chinese University of Hong Kong, Hong Kong 9 Department of Anatomical and Cellular Pathology, The Chinese University of Hong Kong, Hong Kong Correspondence to: Tai-Chung Lam, email: lamtc03@hku.hk Keywords: glioblastoma; BRAF V600E mutation; targeted therapies; BRAF-MEK inhibitors Received: August 20, 2018 Accepted: April 03, 2019 Published: June 04, 2019 ABSTRACT Background Up to 15% of young adults with glioblastoma have the activating oncogenic BRAF V600E mutation, an actionable target of the MAPK signal transduction pathway governing tumor cell proliferation. Small molecule inhibitors of BRAF and MEK, a downstream protein immediately following BRAF, have been shown to confer a survival advantage for patients with BRAF V600E mutant advanced melanoma. We describe our experience using this combined target therapy for two patients with BRAF V600E mutant glioblastoma (GBM) as primary treatment due to extenuating clinical circumstances that prohibited the prescription of standard treatment. Case Presentation The two patients were both 22 years old on presentation. After the initial tumor resection, they both developed rapid deterioration in performance status within a few weeks due to leptomeningeal metastases. In view of the critical condition, BRAF and MEK inhibitors were prescribed as first line treatment. The two patients both achieved dramatic clinical response, which was parallel to the impressive radiological regression of the disease. Unfortunately, the duration of disease control was short as drug resistance developed rapidly. The two patients died 7 and 7.5 month after initial diagnosis of GBM. Conclusions Primary treatment with inhibitors of BRAF and MEK can lead to tumor regression for patients with BRAF V600E mutant glioblastoma. We therefore recommend that all young GBM patients should undergo BRAF V600E mutation testing, especially for those with unusual aggressive clinical course.

Background Fall with head injury is a pervasive challenge, especially in the aging population. Contributing factors for mortality include the development of cerebral contusions and delayed traumatic intracerebral hematoma. Currently, there is no established specific treatment for these conditions. Object This study aimed to investigate the impact of independent factors on the mortality rate of traumatic brain injury with contusions or traumatic subarachnoid hemorrhage. Methods Data were collected from consecutive patients admitted for cerebral contusions or traumatic subarachnoid hemorrhage at an academic trauma center from 2010 to 2016. The primary outcome was the 30-day mortality rate. Independent factors for analysis included patient factors and treatment modalities. Univariate and multivariate analyses were conducted to identify independent factors related to mortality. Secondary outcomes included thromboembolic complication rates associated with the use of tranexamic acid. Results In total, 651 consecutive patients were identified. For the patient factors, low Glasgow Coma Scale on admission, history of renal impairment, and use of warfarin were identified as independent factors associated with higher mortality from univariate and multivariate analyses. For the treatment modalities, univariate analysis identified tranexamic acid as an independent factor associated with lower mortality (P = 0.021). Thromboembolic events were comparable in patients with or without tranexamic acid. Conclusion Tranexamic acid was identified by univariate analysis as an independent factor associated with lower mortality in cerebral contusions or traumatic subarachnoid hemorrhage. Further prospective studies are needed to validate this finding.

Introduction Normal skull base structures are destroyed either by the skull base pathology itself or during surgery that results in cerebrospinal fluid (CSF) leak. Skull base repair is usually performed transnasally by using a nasal septal flap. But when NSF is not available and failed repeated transnasal repair, a cranionasal repair with frontal pericranial flap (PF) can be attempted to achieve the highest successful chance. We performed a dual layer/split PF repair of a skull base defect using cranionasal approach and here we describe the technique. Case Description A 74-year-old man suffered from CSF leak and ventriculitis after multiple transnasal surgeries for pituitary macroadenoma despite multiple repairs with intranasal vascularized flaps. We performed repair by cranionasal approach and using frontal PF. The frontal PF was divided into left and right halves. The left half went intradural, through the chiasmatic window to reach the sella and cover the tubercular and sellar defect from above. The right half went through the nasion into the nose to cover the defect from below. So the defect was covered by two vascularized flap from a single frontal PF. The repair was successful with no CSF leak and infection successfully treated by antibiotics. Conclusion We introduced the cranionasal dual layer/split PF technique to repair anterior skull base and successfully stopped the CSF leak in a patient after multiple EEA surgeries. This technique should only be considered in specific difficult situation where usual repair by EEA is impossible.

In emergency neurosurgical patients, evaluation with Glasgow Coma Scale (GCS) alone immediately after stopping sedation post-operatively might not differentiate those with good recovery from those with poor outcomes at 3 months. This study aimed to evaluate the prognostic value of measuring the Bispectral Index (BIS) and the correlation to propofol dosage during the use of sedation in the early post-operative period.This is a prospective study on consecutive post-operative neurosurgical patients admitted to the neurosurgical ICU on propofol sedation. The primary outcome was the correlation between early post-operative BIS and the Propofol dosage with the modified Rankin scale (mRS) at 3 months. Secondary outcomes included the post-operative propofol requirement in patients with good functional outcomes (mRS 0-3) versus poor functional outcomes (mRS 4-6) at 3 months.In total, 728 BIS readings were collected from twenty-four patients for analysis. The BIS readings were significantly correlated to the propofol dosage in patients with good function outcomes at 3 months (p 0.0001). BIS readings in patients with no associations to changes in propofol dosage during their ICU stay had poor outcomes (mRS 4-6) at 3 months (r = -0.0407). For patients with good functional outcomes at 3 months, a significantly higher propofol dosage was used for deep sedation (BIS 40 - 60) during the post-operative period (p 0.001).For emergency neurosurgical patients whose BIS readings had lost correlation to the propofol dosage upon recovery, their functional outcomes at 3 months were poor. For those with good functional outcomes at 3 months, a significantly higher propofol dosage was required for deep sedation during their ICU stay. Patients with preserved correlation of BIS readings to changes in propofol dosages during the early post-operative period were associated with good functional outcomes at 3 months.

BACKGROUND Surgery is the mainstay of meningioma treatment, but improvements in meningioma risk stratification are needed and indications for postoperative radiotherapy are controversial. DNA methylation profiling, copy number variants (CNVs), exome sequencing, and RNA sequencing have improved understanding of meningioma biology, but have not superseded histologic grading, or revealed biomarkers for radiotherapy responses. To address these unmet needs, we optimized and validated a targeted gene expression biomarker predicting meningioma outcomes and responses to radiotherapy. METHODS Targeted gene expression profiling was performed on a discovery cohort of 173 meningiomas (median follow-up 8.1 years) and a validation cohort of 331 meningiomas (median follow-up 6.1 years) treated with surgery (n=504) and postoperative radiotherapy (n=73) at independent, international institutions (70% WHO grade 1, 24% WHO grade 2, 6% WHO grade 3). Optimized targeted gene expression models predicting clinical outcomes (34 genes) or radiotherapy responses (12 genes) were developed from the discovery cohort, and compared to histologic and molecular classification systems by performing DNA methylation profiling, CNV analysis, exome sequencing, and RNA sequencing on the same meningiomas. RESULTS Targeted gene expression profiling achieved a concordance-index of 0.75 ± 0.03 (SEM) for local freedom from recurrence (LFFR) and 0.72 ± 0.03 for overall survival (OS) in the validation cohort, outperforming WHO grade (5-year LFFR delta-AUC 0.15, 95% CI 0.076-0.229, p=0.001) and DNA methylation grouping (delta-AUC 0.075, 95% CI 0.006-0.130, p=0.01) for LFFR, disease-specific survival, and OS. The biomarker was independently prognostic after accounting for WHO grade, extent of resection, primary versus recurrent presentation, CNV status, DNA methylation group, and Ki67 labeling index, and identified meningiomas benefiting from radiotherapy (interaction p-value=0.0008), suggesting postoperative radiotherapy could be refined in 30.2% of cases. CONCLUSIONS Targeted gene expression profiling of 504 meningiomas improves discrimination of meningioma local recurrence, disease-specific survival, and overall survival, and predicts radiotherapy responses.

Purpose/Objective(s) Indications for postoperative radiotherapy after meningioma resection are controversial. DNA methylation profiling identifies meningiomas at risk for recurrence, but logistic and technical barriers have encumbered clinical translation of this approach. The aim of this study was to optimize and validate a clinically-tractable targeted gene expression biomarker to predict meningioma outcomes and responses to postoperative radiotherapy. Materials/Methods Targeted gene expression and Illumina 850k DNA methylation profiling were performed on a discovery cohort of 173 meningiomas (median follow-up 7.8 years) and an external validation cohort of 331 meningiomas (median follow-up 5.8 years) from patients treated with surgery (n = 504) and postoperative radiotherapy (n = 73) at independent, international institutions (70% WHO grade 1, 24% WHO grade 2, 6% WHO grade 3). RNA sequencing was performed on the discovery cohort, and 125 genes were selected for targeted gene expression profiling based on associations with meningioma recurrence. Regularized Cox regression was used to develop continuous gene expression risk score for local freedom from recurrence (LFFR). The model (34 meningioma genes and 7 housekeeping genes) and risk quartiles (low, low-intermediate, high-intermediate, and high) were locked and validated on the external cohort. Multivariate regressions (MVR) incorporating WHO grade, DNA methylation grouping, extent of resection, primary versus recurrent presentation, and postoperative radiotherapy were used to assess the risk score across clinical contexts. Results The gene expression risk score (concordance-index 0.78 ± 0.03) outperformed DNA methylation grouping (0.71 ± 0.03) and WHO grade (0.65 ± 0.03) in stratifying meningioma LFFR in the validation cohort (n = 331). The risk score classified 43% of WHO grade 1 meningiomas as high-intermediate (n = 82) or high risk (n = 34), with 5-year LFFR and overall survival (OS) of 83% and 89% for high-intermediate risk WHO grade 1 meningiomas, and 41% and 73% for high risk WHO grade 1 meningiomas, respectively. Low risk WHO grade 1 meningiomas (n = 50) had 5-year LFFR and OS of 92% and 88%, respectively. High and high-intermediate risk scores were independently prognostic for LFFR (HR 2.9, 95% CI 1.2-4.4) and OS (HR 2.7, 95% CI 1.3-5.6) on MVR. An interaction term between postoperative radiotherapy and risk score was predictive for LFFR (P = 0.046) and OS (P = 0.001) on MVR in the validation cohort, suggesting meningiomas with higher risk scores derived greater benefit from postoperative radiotherapy. Conclusion Here we use targeted gene expression profiling to develop a risk score predicting meningioma outcomes and responses to postoperative radiotherapy. This cost-effective assay outperforms DNA methylation grouping and WHO grade in discriminating meningioma outcomes, and may be useful for guiding clinical trial design.

Meningiomas arising from the meningothelial central nervous system lining are the most common primary intracranial tumors, and a significant cause of neurologic morbidity and mortality1. There are no effective medical therapies for meningioma patients2,3, and new treatments have been encumbered by limited understanding of meningioma biology. DNA methylation profiling provides robust classification of central nervous system tumors4, and can elucidate targets for molecular therapy5. Here we use DNA methylation profiling on 565 meningiomas integrated with genetic, transcriptomic, biochemical, and single-cell approaches to show meningiomas are comprised of 3 epigenetic groups with distinct clinical outcomes and biological features informing new treatments for meningioma patients. Merlin-intact meningiomas (group A, 34%) have the best outcomes and are distinguished by a novel apoptotic tumor suppressor function of NF2/Merlin. Immune-enriched meningiomas (group B, 38%) have intermediate outcomes and are distinguished by immune cell infiltration, HLA expression, and lymphatic vessels. Hypermitotic meningiomas (group C, 28%) have the worst outcomes and are distinguished by convergent genetic mechanisms misactivating the cell cycle. Consistently, we find cell cycle inhibitors block meningioma growth in cell culture, organoids, xenografts, and patients. Our results establish a framework for understanding meningioma biology, and provide preclinical rationale for new therapies to treat meningioma patients.

SUMMARYMeningiomas arising from the meningothelial central nervous system lining are the most common primary intracranial tumors, and a significant cause of neurologic morbidity and mortality1. There are no effective medical therapies for meningioma patients2,3, and new treatments have been encumbered by limited understanding of meningioma biology. DNA methylation profiling provides robust classification of central nervous system tumors4, and can elucidate targets for molecular therapy5. Here we use DNA methylation profiling on 565 meningiomas integrated with genetic, transcriptomic, biochemical, and single-cell approaches to show meningiomas are comprised of 3 epigenetic groups with distinct clinical outcomes and biological features informing new treatments for meningioma patients. Merlin-intact meningiomas (group A, 34%) have the best outcomes and are distinguished by a novel apoptotic tumor suppressor function ofNF2/Merlin. Immune-enriched meningiomas (group B, 38%) have intermediate outcomes and are distinguished by immune cell infiltration,HLAexpression, and lymphatic vessels. Hypermitotic meningiomas (group C, 28%) have the worst outcomes and are distinguished by convergent genetic mechanisms misactivating the cell cycle. Consistently, we find cell cycle inhibitors block meningioma growth in cell culture, organoids, xenografts, and patients. Our results establish a framework for understanding meningioma biology, and provide preclinical rationale for new therapies to treat meningioma patients.

BACKGROUND Meningioma treatments are limited due to incomplete understanding of meningioma biology. To address this, we performed multiplatform molecular profiling on 565 meningiomas with comprehensive clinical data to define genomic drivers and identify therapeutic vulnerabilities. METHODS DNA methylation profiling was performed on meningiomas from UCSF (n=200, discovery) and Hong Kong University (n=365, validation). Median follow-up was 5.6 years, and there were 388/142/35 WHO grade I/II/III meningiomas. Copy number variants (CNVs) were calculated for all meningiomas, and RNA sequencing was performed on UCSF meningiomas. Cell type deconvolution, metagenomics, CRISPR, and pharmacology were used for mechanistic and functional validation. RESULTS Unsupervised hierarchical clustering of differentially methylated DNA probes revealed that meningiomas were comprised of 3 epigenetic subgroups associated with good, intermediate, and poor outcomes, with representation from all WHO grades in each subgroup. Meningiomas from the subgroup with the best outcomes (52% WHO grade I) were distinguished by recurrent gain of Chr5. Meningiomas from the subgroup with intermediate outcomes (31% WHO grade II) were distinguished by genomic stability, enrichment of innate immune genes, and immune infiltration in the setting of endogenous retroviral gene re-expression, a mechanism of immune recruitment. The most aggressive subgroup of meningiomas (57% WHO grade III) was distinguished by genomic instability, including recurrent loss of Chr22q harboring NF2, and decreased immune infiltration. Consistently, NF2 suppression in primary meningioma cells derived from immunogenic meningiomas decreased expression of innate immune genes critical for immune recruitment, suggesting a novel immunostimulatory function of NF2. The most aggressive subgroup of meningiomas were further distinguished by activation of the mitogenic FOXM1 transcriptional program, and recurrent loss of Chr9p harboring CDKN2A/B, which rendered primary meningioma cells from this subgroup susceptible to CDK4/6 inhibitors. CONCLUSIONS Meningiomas are comprised of 3 epigenetic subgroups defined by genetic mechanisms driving immune infiltration in the tumor microenvironment and meningioma cell proliferation.

One of the treatment options for long segment common carotid artery (CCA) occlusion is bypass surgery with different combinations of donors and receipts. Using vertebral artery (VA) as the donor for CCA occlusion was uncommonly reported. The reported cases were using jump graft to connect V3 segment of VA to either CCA or ICA. We describe our patient using V2 segment as the donor for VA-CCA bypass as treatment for CCA occlusion. Our patient was a 51 years old gentleman with Marfan syndrome and had multiple operations that included total arch replacement. He presented with sudden onset of spontaneous right frontal subarachnoid haemorrhage and repeated episodes of TIA with left upper limb numbness. CTA showed occluded right CCA and anastomosis between branches from subclavian artery and occipital artery. CT perfusion showed hypoperfusion of right hemisphere. To avoid damaging the anastomosis at subclavian artery and occipital artery, we decided for V2-RAG (radial artery graft)-CCA bypass. It was done by exposing the V2 segment at C4/5 level, performing end-to-side anastomoses at V2-RAG and RAG-CCA junctions where the RAG was underneath the internal jugular vein. Patient had no new deficits after surgery and no more TIAs. CTA performed one week after surgery showed patent RAG. In conclusion, using V2 for VA-CCA bypass is technically feasible and may have theoretical advantages over using V3. V2-CCA bypass is an option for CCA occlusion in very selected patients.

Background Ischemic stroke due to large vessel occlusion can be effectively treated with thrombectomy but access to this treatment is limited in many parts of the world. Local incidence of large vessel occlusion is critical in determining the development of thrombectomy service, but reliable data from Asian countries are lacking. Aims We performed a population-based study to estimate the burden of large vessel occlusion and the service gap for thrombectomy in Hong Kong. Methods All acute ischemic stroke patients admitted in 2016 to the public healthcare system, which provided 90% of the emergency healthcare in the city, was identified from the Hong Kong Hospital Authority’s central electronic database. The diagnosis of large vessel occlusion was retrospectively verified by two independent cerebrovascular specialists in a randomly sampled cohort based on clinical and neuroimaging data. The incidence of large vessel occlusion in the population was estimated through weighting the sample results and compared with the thrombectomy data in the same period. Results There were 6859 acute ischemic stroke patients treated in the public health system in 2016. Amongst the 300 patients randomly sampled according to diagnosis coding, 130 suffered from anterior circulation large vessel occlusion. This translated to 918 patients (95% CI 653–1180) and 13.3% of all ischemic stroke patients. The estimated incidence of anterior circulation large vessel occlusion was 12.5 per 100,000 persons per year (95% CI 11.7–13.4). Large vessel occlusion stroke patients were more commonly female than male (67.4% vs. 31.6%, p = 0.003), and were older than non-large vessel occlusion stroke patients (mean of 80.5 years vs. 71.4 years, p = Conclusion The estimated incidence of anterior circulation large vessel occlusion in the Hong Kong Chinese population is lower than that in the West. There is however a substantial service gap for endovascular thrombectomy with less than 10% of large vessel occlusion patients receiving thrombectomy.

Background Neurogenic bladder refers to dysfunction of the urinary bladder secondary to diseases of the nervous system that result in problems with urine storage, micturition, or both. The most common causes are multiple sclerosis and spinal cord injury. Patients commonly present with recurrent UTIs, obstructive uropathies, and urinary retention. Without proper treatment, neurogenic bladder may result in nephropathy and renal failure, both of which have a significant negative impact on the health and life expectancy of patients. Restoration of lost neural function using artificial stimulators is a feasible therapeutic strategy. This article reviews the pathophysiology of neurogenic bladder and the 2 most commonly employed sacral nerve stimulation methods—the Brindley procedure and sacral neuromodulation.

BACKGROUND The development of next generation sequencing (NGS) based comprehensive genomic profiling (CGP) has enabled identification of druggable somatic mutations in brain tumours. This cohort reviewed the efficacy of CGP-guided precision treatment in a tertiary neuro-oncology centre. METHODOLOGY From May 2017 to May 2020, CGP were arranged for 43 patients. All patients had exhausted conventional treatments or received CGP for clinical trial screening. Targeted deep NGS was used to assess the mutational status, single nucleotide variant, small insertions and deletions and copy number variant of 440 cancer-related genes. RESULTS The diagnoses of the 43 patients were GBM (n=23), high grade glioma (n=11), brain metastases (n=4), chordoma (n=3), atypical choroid plexus papilloma (n=1) and meningioma (n=1). In most of the patients (42/43, 97.7%), CGP identified at least one druggable targets with a median of 3. Based on the CGP, 27 patients received precision treatment (62.7%). Among these, 14 were GBM and 6 were other high grade glioma. Treatment given included PARP inhibitors, immunotherapy, multi-kinase inhibitor, selective CDK4/6 inhibitor and mTOR inhibitor. Clinical benefit was achieved in 20 patients out of 27 (74%), including 2 complete response (7.4%), 9 partial response (33.3%) and 9 stable disease (33.3%). The median progression free survival (PFS) were 183 days [95% confident intervals (CI): 81–302 days]. For GBM/high grade glioma patients, median PFS was 125 days [95% CI: 52–215] and six-month PFS was 32.7%. Treatment toxicity was mild except two patients developed grade 3 complications and one grade 5 complication (fatal neutropenic fever). For the 16 patients who did not receive precision treatment, one had no druggable target identified, nine were still stable on standard therapies, 6 were too weak when CGP was available. CONCLUSION CGP guided precision treatment for selected, advanced neuro-oncological patients yielded modest clinical efficacy and satisfactory safety profile in real world setting.

This operative video demonstrates an open surgical thrombectomy for a 61-yr-old woman with failed endovascular embolectomy in acute ischemic stroke. Good functional outcome can be achieved when this operation is timely performed within the therapeutic window. This patient has atrial fibrillation. She was admitted for sudden onset of left-sided hemiplegia and aphasia. National Institutes of Health Stroke Scale (NIHSS) was 20/42 before the operation. Computed tomography (CT) cerebral angiogram showed right internal cerebral artery (ICA) occlusion from the cervical portion. Urgent intra-arterial (IA) thrombectomy was started 2 h after symptom onset, but failed despite the use of a stentriver and a large-bore aspiration catheter together. Emergency rescue open thrombectomy was performed with right pterional craniotomy 6 h after symptom onset. Sylvian fissure was dissected to expose the supraclinoid ICA, ICA bifurcation, A1, and M1. A transverse arteriotomy was made at the ICA bifurcation and open surgical thrombectomy was performed. Reperfusion was established in 86 min after skin incision. Intraoperative indocyanine green video-angiography showed patent flow over ICA bifurcation to M1 and A1. She had a good recovery with the return of the left-sided power and was discharged home. At 2-mo postoperative assessment, she was able to walk unaided independently. The modified Barthel Index (BI) was 74/100. Her activity of daily living was independent. We must emphasize IA thrombectomy is the standard treatment, and the role of open surgery remains a potential rescue procedure. Good functional outcome can be achieved when emergency rescue open thrombectomy is performed within the therapeutic window.

Background Iatrogenic cerebral venous sinus injury and occlusion may occur during resection of parasagittal meningioma and lateral skull base surgery. The former involves the superior sagittal sinus, and direct surgical repair is associated with good results. Outcome of direct repair of transverse–sigmoid sinus injury is less clear. We present a patient with iatrogenic sigmoid sinus injury in whom direct repair was complicated by subsequent thrombosis that was successfully salvaged by combined endovascular mechanical and chemical thrombolysis. Case Description A 60-year-old man with left tentorial atypical meningioma had disease recurrence after 3 excisions. Angiography revealed that the straight sinus and torcular and bilateral transverse sinuses were occluded. He underwent a fourth craniotomy with inadvertent occlusion of the transverse–sigmoid sinus junction. Direct surgical repair was done but was complicated by thrombosis. Mechanical endovenous thrombectomy was done followed by continuous urokinase infusion for 1 week. Digital subtraction angiography performed 7 days after endovascular treatment showed improved venous drainage through the left transverse–sigmoid sinus junction. The patient was ambulatory and fully independent, with no new neurologic deficit. Conclusions This case emphasizes the need to preserve every vein, especially when major venous sinuses have been obliterated. Detailed study of high-quality preoperative digital subtraction angiography is extremely important. Venous injury should be repaired immediately whenever possible. Postrepair venous sinus thrombosis may be effectively salvaged by endovascular thrombectomy for rapid recannulation, with or without combined use of continuous in situ thrombolytic therapy.

Hereditary haemorrhagic telangiectasia (HHT), or Osler–Weber–Rendu syndrome, is an autosomal dominant condition characterized by recurrent epistaxis, multiple telangiectasia and visceral vascular malformations. Brain abscess is a common presentation secondary to pulmonary arteriovenous malformation (AVM) in HHT patients. The prevalence of HHT in the Chinese population is not known, and is not commonly report. Here, we report on a Chinese patient who suffered from HHT and presented with multiple brain abscesses and a renal abscess. Upon further investigation of the patient's medical history and a physical examination, it was found that he had recurrent epistaxis and telangiectasia over his tongue, as well as fingers. Subsequent examination found pulmonary and hepatic AVM. He had a fair recovery after treatment of brain abscesses and pulmonary AVM. We believe HHT is underreported in the Chinese population. Simple history taking and physical examination in patients with a brain abscess can aid diagnosis and prevent complications with prophylactic treatment.

Background High-flow extracranial–intracranial (EC-IC) bypass followed by sacrifice of the native internal carotid artery (ICA) is a recognized treatment option for giant ICA aneurysm and skull base tumor involving the ICA. Distal clipping at the supraclinoid portion of the ICA is technically straightforward, but it can potentially compromise ophthalmic artery (OA) perfusion. Because of the extensive EC-IC anastomoses with the OA, visual symptoms are fortunately uncommon. We report a patient who developed complete blindness after distal trapping of the supraclinoid ICA; it was reversed after emergency clip removal. Case Description Our patient is a 47-year-old man with recurrent nasopharyngeal carcinoma in close proximity to the left petrosal ICA. The first stage of the procedure involved an EC-IC bypass using radial artery graft, followed by a second stage with combined craniofacial excision. Trapping of the native ICA was achieved using a permanent aneurysm clip placed at the supraclinoid ICA distal to the origin of the OA. He complained of a new onset of complete left eye visual loss approximately 6 hours after the distal aneurysm clip was applied. He was immediately sent to the operating theatre for the removal of the supraclinoid aneurysm clip. On the next day, his vision improved and left pupil became reactive again. Discussion OA flow following ICA trapping is complicated and precarious. Delayed onset of visual loss is possible. Prompt action by direct exploration and clip removal is needed and can be effective in reversing blindness.

Background Natural killer cell lymphoma is an uncommon hematologic malignancy, and central nervous system metastasis is rare. The classic magnetic resonance imaging appearance of lymphoma in the brain is T1 hypointense with strong homogeneous gadolinium enhancement, variable T2 signal, and restricted diffusion on diffusion-weighted images. Gadolinium enhancement is an important feature to differentiate lymphoma from infarction. Case Description We present the case of a middle-aged man who presented with recurrent natural killer cell lymphoma that metastasized to the cerebellum. Computed tomography and magnetic resonance imaging did not show a contrast-enhancing lesion; imaging features were more suggestive of cerebral infarction. The patient subsequently died, and postmortem examination confirmed natural killer cell lymphoma metastasis to the cerebellum. Conclusions Lymphoma can mimic cerebral infarction on computed tomography and magnetic resonance imaging. An imaging appearance of cerebral infarction in a patient with a history of lymphoma should raise suspicions of lymphoma metastasis.

Background Primary central nervous system (CNS) natural killer (NK)-cell lymphoma is rare with only 7 cases reported previously. Magnetic resonance spectroscopy (MRS) and [ 18 F]fluorodeoxyglucose (FDG) positron emission tomography (PET) are frequently used for disease diagnosis and monitoring. Choline (CHO) PET is gaining popularity for identifying CNS lesions because of its high disease to background radioactivity ratio compared with FDG. Normally, CNS lymphoma shows high choline uptake on CHO-PET and a high choline peak on MRS. We present an unusual case of primary CNS NK-cell lymphoma with high choline uptake but absence of a high choline peak on MRS. Case Description A 39-year-old woman presented with subacute onset of cognitive deterioration. Magnetic resonance imaging of the brain showed a gadolinium-enhancing lesion in the left temporal lobe. MRS showed suppressed N -acetyl-aspartate and the absence of a high choline peak. CHO-PET confirmed that it was the only hypermetabolic lesion in the body with moderate uptake of choline. The differential diagnoses included encephalitis and neoplasm. She was initially treated for the former but did not respond to steroids, intravenous immunoglobulin, and plasmapheresis. A surgical biopsy later confirmed NK-cell lymphoma. She was then treated as primary CNS NK-cell lymphoma with intravenous and intrathecal chemotherapy. Conclusions We presented a unique case of primary CNS NK-cell lymphoma with atypical imaging findings characterized by moderately increased uptake of choline without a corresponding high choline peak on MRS. Although CHO-PET was suggestive of malignancy, surgical biopsy was required to confirm the diagnosis.

Background Hypertrophic pachymeningitis has been described as a manifestation of a number of conditions, like infection and neoplasms such as dural carcinomatosis or lymphomas. IgG4-related hypertrophic pachymeningitis is a new entity identified during the past decade and most reports described pachymeningeal involvement only. Case Description We present a 58-year-old woman with isolated IgG4 hypertrophic pachymeningitis at the falx cerebrii that exhibited cerebral parenchymal invasion. She initially presented with left lower limb weakness. Magnetic resonance imaging of brain showed a contrast enhancing lesion located at the falx and that eroded into the right frontal lobe. Subsequent excisional biopsy confirmed the lesion with brain parenchyma invasion. The pathologic diagnosis was IgG4-related disease. She had no evidence of extracranial involvement. Conclusions Overall, this is an uncommon condition that may exhibit parenchymal invasion. Surgical biopsy would serve to establish a definitive diagnosis, and prompt comprehensive management of what is essentially a systemic and treatable condition.