Somatic MAP3K3 and PIK3CA mutations in sporadic cerebral and spinal cord cavernous malformations.

Cavernous malformations affecting the CNS occur in ∼0.16-0.4% of the general population. The majority (85%) of cavernous malformations are in a sporadic form, but the genetic background of sporadic cavernous malformations remains enigmatic. Of the 81 patients, 73 (90.1%) patients were detected carrying somatic missense variants in two genes: MAP3K3 and PIK3CA by whole-exome sequencing. The mutation spectrum correlated with lesion size (P = 0.001), anatomical distribution (P < 0.001), MRI appearance (P = 0.004) and haemorrhage events (P = 0.006). PIK3CA mutation was a significant predictor of overt haemorrhage events (P = 0.003, odds ratio = 11.252, 95% confidence interval = 2.275-55.648). Enrichment of endothelial cell population was associated with a higher fractional abundance of the somatic mutations. Overexpression of the MAP3K3 mutation perturbed angiogenesis of endothelial cell models in vitro and zebrafish embryos in vivo. Distinct transcriptional signatures between different genetic subgroups of sporadic cavernous malformations were identified by single cell RNA sequencing and verified by pathological staining. Significant apoptosis in MAP3K3 mutation carriers and overexpression of GDF15 and SERPINA5 in PIK3CA mutation carriers contributed to their phenotype. We identified activating MAP3K3 and PIK3CA somatic mutations in the majority (90.1%) of sporadic cavernous malformations and PIK3CA mutations could confer a higher risk for overt haemorrhage. Our data provide insights into genomic landscapes, propose a mechanistic explanation and underscore the possibility of a molecular classification for sporadic cavernous malformations.

Technique Nuances for Functional Preservation of Lower Cranial Nerves during Surgical Management of Ventral Foramen Magnum Meningiomas Via a Dorsal Lateral Approach.

BACKGROUND: This study established novel technique nuances in surgery for ventral foramen magnum meningiomas (vFMMs) via a dorsal lateral approach. METHODS: From July 2012 to July 2019, 37 patients with vFMMs underwent tumor resection surgery and were operated on with a dorsal lateral approach. Two safe zones were selected as the entrance of the surgical corridor. Safe zone I was located between the dural attachment of the first dental ligament (FDL) and the branches of C1; safe zone II lay between the dural attachment of the FDL and the jugular foramen. The tumor was debulked first through safe zone I and then through safe zone II. The tumor was removed through a trajectory from the caudal to cephalad to allow tumor debulking from below and downward delivery, away from the brainstem and lower cranial nerves. RESULTS: Thirty-three patients underwent gross total resection, and 4 patients underwent subtotal resection. Four patients transiently required a nasogastric feeding tube. All patients recovered within 3 months postoperatively. Three patients (8.1%) developed permanent mild hoarseness and dysphagia as a result of postoperative damage of cranial nerves IX and X. One patient underwent tracheotomy. No patient experienced tumor recurrence during the follow-up period. CONCLUSIONS: We established a minimal retraction principle, in which the selection of 2 safe zones as the entrance of the surgical corridor, tumor removal from the inferior to superior direction, and debulking followed by devascularization were the key elements to implement the minimal retraction principle in vFMM surgery.

Surgical treatment of pontine cavernous malformations via subtemporal transtentorial and intradural anterior transpetrosal approaches.

The aim of this study was to report our surgical experience on resection of the pontine cavernous malformations (CMs) via subtemporal transtentorial approach (STTA) and intradural anterior transpetrosal approach (ATPA). Clinical data were retrospectively reviewed in 61 patients with pontine CMs that were surgically treated by the STTA and the intradural ATPA. The surgical procedures, complications, and outcomes were analyzed. The study consists of 61 patients with a total of 61 pontine CMs. Other than 4 lesions located medially in the pons, all CMs were in the lateral pons with a left or right lateral epicenter (the left/right ratio was 22/35). Totally, 11 patients (18.0%) with lesions located in the upper pons were treated by the STTA, and 50 patients (82.0%) with lesions involving the lower pons were treated by the intradural ATPA. Postoperatively, the complete resection was achieved in 58 patients (95.1%) and incomplete resection in 3 patients (4.9%). Twenty-seven patients (44.3%) suffered from a new or worsened neurological deficit in the immediate postoperative period, and 8 patients (13.1%) encountered a non-neural complication, including rebleeding, cerebrospinal fluid leak, intracranial infection, and pulmonary infection, and 3 patients had contusion of temporal lobe. With a mean follow-up of 54.2 months, the patients' neurological condition had improved in 43 cases (71.6%), not changed in 10 cases (16.7%), and worsened in 7 cases (11.7%), respectively. The Karnofsky Performance Scale (KPS) score evaluated at the last time for per patient was significantly better than their baseline status (t = 6.677, p < 0.001). However, 21 patients (35.0%) suffered from a new or worsened persistent postoperative deficit. The lateral and anterolateral pons can be exposed well by the subtemporal transtentorial and intradural anterior transpetrosal approaches. Lesions of CMs located in the lateral pons, including ventrolateral and dorsolateral pons, could be totally removed by these two lateral approaches with an acceptable surgical morbidity.

The Differences Between Intracranial Mesenchymal Chondrosarcoma and Conventional Chondrosarcoma in Clinical Features and Outcomes.

OBJECTIVE: To report differences in clinical features and outcomes between intracranial mesenchymal chondrosarcoma (MCS) and conventional chondrosarcoma (CCS). METHODS: Clinical data of patients with primary intracranial MCS and CCS were retrospectively extracted and analyzed to compare differences between MCS and CCS. RESULTS: Seventy-four patients with intracranial chondrosarcoma (61 cases with MCS and 13 cases with CCS) were included. Compared with patients with CCS, patients with MCS presented at a younger mean age (21.1 years vs. 34.5 years, P < 0.001) and had a poor mean preoperative Karnofsky performance scale score (64.6 vs. 77.8, P = 0.014). Compared with CCS, MCS was less often located in the skull base (38.5% vs. 96.7%, P < 0.001) and had a larger tumor volume (87.8 cm3 vs. 26.7 cm3, P < 0.001). Rates of gross total resection in MCS and CCS subgroups were 41.1% (n = 25) and 46.2% (n = 6), respectively; rates of adjuvant radiotherapy postoperatively were 44.2% (n = 27) and 46.2% (n = 6), respectively. After mean follow-up of 41.7 months, 1-year, 3-year, and 5-year overall survival and progression-free survival of MCS were significantly shorter than overall survival and progression-free survival of CCS. Multivariate analysis revealed that tumor pathology and extent of surgery were independent predictors for tumor recurrence. CONCLUSIONS: Clinical features of MCS are quite different from CCS. Treatment strategies used for CCS do not yield satisfactory outcomes for MCS. Treatment of MCS should be aggressive and individualized.

Surgical Management of Brainstem Cavernous Malformation: Report of 67 Patients.

BACKGROUND: Brainstem cavernous malformations (CMs) are benign lesions, often show an acute onset, and result in a high rate of morbidity. Surgical resection could inhibit the progressive deterioration of neurologic function caused by repetitive hemorrhage. This study aimed to summarize timing, approaches, and techniques of surgery and to evaluate outcomes of treatment. METHODS: Between March 2011 and May 2013, 67 patients (32 male, 35 female; average age 40 years; range, 14-68 years) with brainstem CMs received surgical treatment. Clinical presentation, surgical approaches, and results of follow-up were retrospectively analyzed. RESULTS: Seven surgical approaches were used: orbitozygomatic approach (1 case), suboccipital transtentorial approach (Poppen approach; 3 cases), subtemporal transtentorial approach (32 cases), subtemporal transtentorial/anterior petrosectomy approach (9 cases), suboccipital retrosigmoid approach (3 cases), midline suboccipital approach (16 cases), and far lateral approach (3 cases). Total resection of the brainstem CM was achieved in all cases (100%). No operative mortality was encountered. Nine patients had new symptoms after surgery: 3 had diplopia, 3 had facial numbness, 1 had numbness of contralateral limbs, 1 had transient aphasia, and 1 had reduced muscle strength of contralateral limbs. Symptoms significantly improved in 23 patients (34.3%), symptoms were unchanged in 36 patients (53.7%), and new postoperative symptoms occurred in 9 patients (13.4%). CONCLUSIONS: Choosing a proper surgical approach and using appropriate techniques are fundamental for favorable outcomes of patients with brainstem CMs.

The Differentially Expressed Genes of Human Sporadic Cerebral Cavernous Malformations.

OBJECTIVES: To understand the development of sporadic cerebral cavernous malformations (SCCM) comprehensively, we analyzed gene expression profiles in SCCMs by gene microarray. METHODS: The total number of the specimens collected in our study was 14, 7 of which were SCCMs, and the others were controls that were obtained from normal brain vessels. The total RNA was extracted and hybridized with oligonucleotide array containing 21522 genes. The analysis of Gene Ontology (GO) items and molecular pathways was performed based on the GO and Kyoto Encyclopedia of Genes and Genomes databases. The gene coexpression networks were constructed to identify the core genes regulating the progression of SCCMs. RESULTS: A total of 785 probes, showing differentially expressed genes (DEGs) between the 2 groups, were found by the gene chips. According to the analysis based on GO and Kyoto Encyclopedia of Genes and Genomes, 286 GO terms and 53 pathways were identified to be significantly relevant with the DEGs. All differential gene interactions were analyzed and the core genes were selected in the coexpression networks. CONCLUSIONS: The gene expression profiles obtained from SCCMs were significantly distinct from those of control brain vascular specimens. These DEGs are related to multiple molecular signal pathways, such as the mitogen-activated protein kinase pathway, cytokine-cytokine receptor interaction, focal adhesion, and inflammatory response. According to the analysis of the core genes selected in the gene coexpression networks, we postulated that CSF1R, XCL1, KCNMB1, RHOG, and TJP1 might exert enormous functions in the pathogenesis of SCCMs. However, further studies are required to aid in the clinical diagnosis and prevention of SCCMs.

Brainstem Cavernous Malformations: Surgical Indications Based on Natural History and Surgical Outcomes.

Cavernous malformations (CMs) are uncommon lesions occurring in the central nervous system, with an incidence of approximately 0.5% in the general population and constituting 5%-10% of all intracranial vascular malformations. Among CMs, prevalence within the brainstem as reported in the literature has ranged from 4% to 35%. With their precarious location and potentially devastating clinical events, brainstem CMs have attracted attention from neurosurgeons, and with these surgeons' unrelenting efforts, the microsurgical techniques to treat these lesions in the brainstem have greatly improved in recent decades. Although surgical outcomes reported in the literature have been satisfying, surgical intervention has become increasingly contraindicated because of the tendency for a benign clinical course in brainstem CMs, after weighing this fact against the high risk of surgical morbidity. Thus, it is advisable to operate on patients with symptomatic lesions abutting the pial or ependymal surface of the brainstem or where lesions are accessible to safe entry zones, which have caused more than 1 significantly symptomatic hemorrhage and can be defined as aggressive. However, treatment remains controversial for deep-seated lesions away from the surface of the brainstem or lesions that are inaccessible to safe entry zones. Other treatments, such as radiosurgery and medication, are still debatable, which might be as an alternative for lesions amenable to but at high risk with surgery.

Clinical and prognostic significance of prokineticin 1 in human gliomas.

The objective of this study was to explore the expression and the clinical and prognostic significance of prokineticin 1 (PROK1) in human gliomas. The expression of PROK1 in 60 patients with glioma and in eight control cases (patients with traumatic brain injury) by immunohistochemistry (IHC). The associations between the differences in expression and pathology grades were analyzed statistically. The positive rates of PROK1 expression in normal brain and glioma tissue were 25.0% (2/8) and 93.3% (56/60), respectively. PROK1 expression in glioma tissue was higher than that in normal tissue (P<0.05). The positive rates of PROK1 expression in low-grade gliomas (LGGs, grades I and II) and high-grade gliomas (HGGs, grades III and IV) were 66.7% (8/12) and 100% (48/48), respectively, the positive rates in HGG were higher than those in LGG (P<0.01). PROK1 is an angiogenic growth factor that is related with metastatic ability of tumor, we also correlated PROK1 expression with NFAT expression. Expression of PROK1correlated significantly with expression of NFAT (r=0.524, P<0.01), but not with patient sex and age. Glioma patients with higher expressing PROK1 had a significantly shorter progression-free survival time, increasing levels of PROK1 expression significantly correlated with reduced survival times when all patients with glioma were considered (P<0.01). These results suggested that PROK1 positivity and protein expression levels are of significant clinical and prognostic value in human gliomas, which significantly correlates with the survival in gliomas, PROK1 may regulate the progression of glioma via the NFAT pathway.

Foramen magnum meningiomas: surgical results and risks predicting poor outcomes based on a modified classification.

OBJECTIVE This study aimed to evaluate neurological function and progression/recurrence (P/R) outcome of foramen magnum meningioma (FMM) based on a modified classification. METHODS This study included 185 consecutive patients harboring FMMs (mean age 49.4 years; 124 females). The authors classified the FMMs into 4 types according to the previous classification of Bruneau and George as follows: Type A (n = 49, 26.5%), the dural attachment of the lesion grows below the vertebral artery (VA); Type B (n = 39, 21.1%), the dural attachment of the lesion grows above the VA; Type C1 (n = 84, 45.4%), the VA courses across the lesion with or without VA encasement or large lesions grow both above and below the bilateral VA; and Type C2 (n = 13, 7.0%), Type C1 plus partial/total encasement of the VA and extradural growth. RESULTS The median preoperative Karnofsky Performance Scale (KPS) score was 80. Gross-total resection (GTR) was achieved in 154 patients (83.2%). Lower cranial nerve morbidity was lowest in Type A lesions (16.3%). Type C2 lesions were inherently larger (p = 0.001), had a greater percentage of ventrolateral location (p = 0.009) and VA encasement (p < 0.001), lower GTR rate (p < 0.001), longer surgical duration (p = 0.015), higher morbidity (38.5%), higher P/R rate (30.8%, p = 0.009), and poorer recent KPS score compared with other types. After a mean follow-up duration of 110.3 months, the most recent follow-up data were obtained in 163 patients (88.1%). P/R was observed in 13 patients (7.2%). The median follow-up KPS score was 90. Compared with preoperative status, recent neurological status was improved in 91 (49.2%), stabilized in 76 (41.1%), and worsened in 18 (9.7%) patients. The multivariate Cox proportional hazard regression model demonstrated Type C2 (HR 3.94, 95% CI 1.04-15.0, p = 0.044), nontotal resection (HR 6.30, 95% CI 1.91-20.8, p = 0.003), and pathological mitosis (HR 7.11, 95% CI 1.96-25.8, p = 0.003) as independent adverse predictors for tumor P/R. Multivariate logistic regression analysis identified nontotal resection (OR 4.06, 95% CI 1.16-14.2, p = 0.029) and pathological mitosis (OR 6.29, 95% CI 1.47-27.0, p = 0.013) as independent risks for poor outcome (KPS score < 80). CONCLUSIONS The modified classification helped to predict surgical outcome and P/R in addition to the position of the lower cranial nerves. Preoperative imaging studies and neurological function should be reviewed carefully to establish an individualized management strategy to improve long-term outcome.

The relation between angioarchitectural factors of developmental venous anomaly and concomitant sporadic cavernous malformation.

BACKGROUND: Past studies found that cerebral developmental venous anomaly (DVA) is often concurrent with cavernous malformation (CM). But the reason of the concurrency remains unknown. The purpose of this study was to confirm whether angioarchitectural factors relate to the concurrence and which angioarchitectural factors can induce the concurrency. METHODS: DVA cases were selected from the records of the same 3.0 T MR. The DVA cases was divided into two group which are DVA group and DVA concurrent with CM group. 8 angioarchitectural factors of the DVAs were selected and measured. Statistical analysis was performed by the Pearson chi-square statistic,analysis of variance (ANOVA) and multi-factor logistic regression analysis. RESULTS: Five hundred three DVA lesions were found and 76 CM lesions coexisting with DVA. In the single factor analysis, all the 8 angioarchitectural factors of DVA were related to the concurrency. In the multivariate analysis, 6 angioarchitectural factors. Result of multi-factor logistic regression analysis is Logit(P) = -4.858-0.932(Location) + 1.616(Direction) + 1.757(Torsion) + 0.237(Number) + 2.119(Stenosis rate of medullary vein)-0.015(Angle), goodness of fit is 90.1 %. CONCLUSIONS: The angioarchitectural factors of DVA are related to the concurrency of DVA and CM. 6 angioarchitectural factors may induce the concurrency.

RNaseH2A is involved in human gliomagenesis through the regulation of cell proliferation and apoptosis.

Mutations in the RNaseH2A gene are involved in Aicardi­Goutieres syndrome, an autosomal recessive neurological dysfunction; however, studies assessing RNaseH2A in relation to glioma are scarce. This study aimed to assess the role of RNaseH2A in glioma and to unveil the underlying mechanisms. RNaseH2A was silenced in glioblastoma cell lines U87 and U251. Gene expression was assessed in the cells transfected with RNaseH2A shRNA or scramble shRNA by microarrays, validated by quantitative real time PCR. Protein expression was evaluated by western blot analysis. Cell proliferation was assessed by the MTT assay; cell cycle distribution and apoptosis were analyzed by flow cytometry. Finally, the effects of RNaseH2A on colony formation and tumorigenicity were assessed in vitro and in a mouse xenograft model, respectively. RNaseH2A was successively knocked down in U87 and U251 cells. Notably, RNaseH2A silencing resulted in impaired cell proliferation, with 70.7 and 57.8% reduction in the U87 and U251 cells, respectively, with the cell cycle being blocked in the G0/G1 phase in vitro. Meanwhile, clone formation was significantly reduced by RNaseH2A knockdown, which also increased cell apoptosis by approximately 4.5-fold. In nude mice, tumor size was significantly decreased after RNaseH2A knockdown: 219.29±246.43 vs. 1160.26±222.61 mm3 for the control group; similar findings were obtained for tumor weight (0.261±0.245 and 1.127±0.232 g) in the shRNA and control groups, respectively). In the microarray data, RNaseH2A was shown to modulate several signaling pathways responsible for cell proliferation and apoptosis, such as IL-6 and FAS pathways. RNaseH2A may be involved in human gliomagenesis, likely by regulating signaling pathways responsible for cell proliferation and apoptosis.

Less-aggressive surgical management and long-term outcomes of jugular foramen paragangliomas: a neurosurgical perspective.

OBJECTIVE The aim of this study was to analyze the neurological functional outcome and recurrent risks in surgically treated jugular foramen paragangliomas (JFPs) and to propose an individualized therapeutic strategy. METHODS Clinical charts and radiological information were reviewed retrospectively in 51 consecutive cases of JFPs. Less-aggressive surgical interventions were adopted with the goal of preserving neurovascular structures. Scheduled follow-up was performed. RESULTS The mean age of the patients in the cases reviewed was 41.6 years, and the group included 27 females (52.9%). The mean preoperative Karnofsky Performance Scale (KPS) score was 78.4. The mean lesion size was 3.8 cm. Forty-three cases (84.3%) were Fisch Type D, including 37 cases (72.5%) of Type Di1 and Di2. Thirty-seven cases (72.5%) were Glasscock-Jackson Type III-IV. Gross-total resection and subtotal resection were achieved in 26 (51.0%) and 22 (43.1%) cases, respectively. Surgical morbidities occurred in 23 patients (45.1%), without surgery-related mortality after the first operation. The mean postoperative KPS scores at discharge, 3 months, 1 year, and most recent evaluation were 71.8, 77.2, 83.2, and 79.6, respectively. The mean follow-up duration was 85.7 months. The tumor recurrence/regrowth (R/R) rate was 11.8%. Compared with preoperative status, swallowing function improved or stabilized in 96.1% and facial function improved or stabilized in 94.1% of patients. A House-Brackmann scale Grade I/II was achieved in 43 patients (84.3%). Overall neurological status improved or stabilized in 90.0% of patients. Pathological mitosis (HR 10.640, p = 0.009) was the most significant risk for tumor R/R. A 1-year increase in age (OR 1.115, p = 0.037) and preoperative KPS score < 80 (OR 11.071, p = 0.018) indicated a risk for recent poor neurological function (KPS < 80). Overall R/R-free survival, symptom progression-free survival, and overall survival at 15 years were 78.9%, 86.8%, and 80.6%, respectively. CONCLUSIONS Surgical outcomes for JFPs were acceptable using a less-aggressive surgical strategy. Most patients could adapt to surgical morbidities and carry out normal life activities. Preserving neurological function was a priority, and maximal decompression with or without radiotherapy was desirable to preserve a patient's quality of life when radical resection was not warranted. Early surgery plus preoperative devascularization was proposed, and radiotherapy was mandatory for lesions with pathological mitosis.

Long-Term Functional and Recurrence Outcomes of Surgically Treated Jugular Foramen Schwannomas: A 20-Year Experience.

OBJECTIVE: To investigate the outcomes of jugular foramen schwannomas (JFSs) and to evaluate the risk factors for tumor recurrence and poor final outcomes. METHODS: Between 1993 and 2013, 133 patients (68 female patients) with JFSs were surgically treated. Clinical charts were reviewed, and scheduled follow-up examinations were performed. RESULTS: The average preoperative Karnofsky Performance Scale (KPS) score was 79.6. The JFSs were classified as follows: 65 cases, type A; 15 cases, type B; 5 cases, type C; and 48 cases, type D. Gross total resection was achieved in 107 (80.5%) patients. Transient and permanent morbidities affecting cranial nerves IX and X were 19.8% and 11.5%, respectively. After a mean follow-up duration of 108.0 months, 13 (9.9%) patients experienced recurrence. The most recent KPS scores averaged 83.7. Compared with the preoperative KPS score, the most recent KPS score was improved in 87 (65.4%) patients and stabilized in 29 (21.8%) patients. The presence of a solid tumor (hazard ratio [HR] = 5.815, P = 0.010), nontotal resection (HR = 4.613, P = 0.007), and pathologic mitoses (HR = 11.018, P < 0.001) were independent risk factors for tumor recurrence. Decreased preoperative KPS score (per 10 points) (odds ratio [OR] = 2.483, P = 0.027), a less soft tumor consistency (OR = 2.257, P = 0.039), and a solid tumor (OR = 3.755, P = 0.041) were risk factors for poor long-term outcomes. CONCLUSIONS: Quality of life and preservation of neurologic function are the goals of surgical treatment of JFSs. Favorable long-term surgical outcomes for JFSs can be achieved. Morbidity of cranial nerves IX and X is significant, and patients with nontotal resection or pathologic mitosis should be followed closely.

SET and MYND domain-containing protein 3 is overexpressed in human glioma and contributes to tumorigenicity.

SET and MYND domain-containing protein 3 (SMYD3) is a histone H3 lysine 4 (H3K4) di- and tri-methyltransferase that forms a transcriptional complex with RNA polymerase II and plays an important role in early embryonic lineage commitment through the activation of lineage-specific genes. SMYD3 activates the transcription of oncogenes and cell cycle genes in gastric and breast cancer cells. However, the contribution of SMYD3 in glioma tumorigenesis remains unknown. Here, we determined the expression of SMYD3 and assessed its clinical significance in human glioma. We found that SMYD3 was overexpressed in human glioma but not in normal brain tissue. The level of SMYD3 protein expression in human glioma tissues was directly correlated with the glioma grade. The level of SMYD3 protein expression in human glioma tissues was inversely correlated with patient survival. Enforced SMYD3 expression promoted glioma LN-18 cell proliferation. Inhibition of SMYD3 expression in glioma T98G cells suppressed their anchorage­independent growth in vitro and tumorigenicity in vivo. Furthermore, we found that SMYD3 regulated the expression of p53 protein, which is essential in SMYD3­induced cell growth in glioma cells. These results showed that SMYD3 is overexpressed in human glioma and contributes to glioma tumorigenicity through p53. Therefore, SMYD3 may be a new potential therapeutic target for human malignant glioma.

The association between cerebral developmental venous anomaly and concomitant cavernous malformation: an observational study using magnetic resonance imaging.

BACKGROUND: Some studies reported that cerebral developmental venous anomaly (DVA) is often concurrent with cavernous malformation (CM). But there is lack of statistical evidence and study of bulk cases. The factors associated with concurrency are still unknown. The purpose of this study was to determine the prevalence of concomitant DVA and CM using observational data on Chinese patients and analyze the factors associated with the concurrency. METHODS: The records of all cranial magnetic resonance imaging (MRI) performed between January 2001 and December 2012 in Beijing Tiantan Hospital were reviewed retrospectively. The DVA and CM cases were selected according to imaging reports that met diagnostic criteria. Statistical analysis was performed using the Pearson chi-square statistic for binary variables and multivariable logistic regression analysis for predictors associated with the concurrent CM. RESULTS: We reviewed a total of 165,230 cranial MR images performed during the previous 12 year period, and identified 1,839 cases that met DVA radiographic criteria. There were 205 patients who presented concomitant CM among the 1,839 DVAs. The CM prevalence in DVA cases (11.1%) was significantly higher than that in the non-DVA cases (2.3%) (P<0.01). In the multivariate analysis, we found that DVAs with three or more medullary veins in the same MRI section (adjusted OR = 2.37, 95% CI: 1.73-3.24), infratentorial DVAs (adjusted OR = 1.71, 95% CI: 1.26-2.33) and multiple DVAs (adjusted OR = 2.08, 95% CI: 1.04-4.16) have a higher likelihood of being concomitant with CM. CONCLUSIONS: CM are prone to coexisting with DVA. There is a higher chance of concurrent CM with DVA when the DVA has three or more medullary veins in the same MRI scanning section, when the DVA is infratentorial, and when there are multiple DVAs. When diagnosing DVA cases, physicians should be alerted to the possibility of concurrent CM.

Using the C7-T3 spinous processes as landmarks for the localization of thoracic spinal lesions: technique notes.

The authors describe a method of using the C7-T3 spinous processes visualized on MRI as landmarks for localizing thoracic spinal lesions in 19 cases. This method included six steps. First, the "spinous process nearest to the lesion that was visible on the MRI image" was identified. Second, a dashed line was drawn on the image through the tip of the identified spinous process perpendicular to the skin surface. Third, two additional dashed lines parallel to the first dashed line were drawn from the upper and lower margins of the lesion. Fourth, the distances between the identified process and the two additional dashed lines were measured. Fifth, the same "spinous process nearest to the lesion" was identified by palpation and marked on the patient's skin. Sixth, the upper and lower margins of the lesion were marked on the skin according to the two distances measured in step 4. After the lesion was exposed, the deviations of the lesion margins were measured. All 19 cases of the thoracic spinal lesions were localized correctly using the C7-T3 spinous processes visualized on the MRI images as landmarks without any other evaluation methods. The deviation value for the localization of the tumor margin was 4.1 ± 1.47 mm. Using the C7-T3 spinous processes as landmarks is an accurate, simple, and economic method for lesion localization during thoracic spinal surgery.

Surgical resection of large and giant petroclival meningiomas via a modified anterior transpetrous approach.

The authors describe a modified anterior transpetrous approach (ATPA) for the surgical resection of 21 cases of petroclival meningiomas (PCMs). Briefly, a curved periauricular skin incision was used. The cerebellar tentorium and the dura on the petrous apex were coagulated and incised to expose the petrous apex bone fully. The drilling of the petrous apex bone was performed subdurally and began internally from the trigeminal impression, not exceeding 1.5 cm laterally, not exceeding 6 mm from the posterior edge of the petrous ridge, and not exceeding 8 mm in depth from the surface of the petrous bone. The tumors were removed totally in 12 (57.1%) cases, subtotally in 8 (38.1%) cases, and partially in 1 (4.8%) case. The transient neurological deficit includes mild oculomotor nerve palsy in three cases, abducens nerve palsy in six cases, language disorder in three cases, and mild hemiplegia in two cases. Facial numbness became worse postoperatively in six patients, and only two patients improved at 6 months after surgery. No death occurred in this series. The modified ATPA is an efficient treatment alterative for large or giant PCMs located at the medial and superior internal acoustic meatus with relatively low risk of complications.

Using a modified far-lateral approach to remove hypoglossal neurilemmomas: notes on technique.

OBJECT: In this paper the authors describe a modified far-lateral transcondylar approach to remove hypoglossal neurilemmomas (HGNs). METHODS: Between September 2008 and June 2011, 11 consecutive patients with HGNs underwent tumor removal via a modified far-lateral transcondylar approach. The average age at presentation, tumor characteristics, cranial nerve (CN) deficits, and outcomes were assessed. The modified far-lateral transcondylar approach comprises several important steps. The first step is to remove the limited posterior aspect of the condylar facet to open the hypoglossal canal. The second step is to expose the posterior arch and the transverse process of C-1. A fat layer covers the venous plexus of the vertebral artery, and careful dissection along this surface of the fat layer is important to protect the vertebral artery from damage. The neck muscles are dissected caudally to expose the extracranial component of the tumor, which is located in front of the transverse process of C-1. RESULTS: Eleven cases of HGNs were treated during the study period. The mean patient age was 47.4 ± 8.9 years (range 31-59 years); there were 3 men and 8 women. The mean follow-up period was 14.1 ± 9 months. All patients presented with hypoglossal nerve deficits; other commonly observed deficits included glossopharyngeal and vestibular/cochlear nerve deficits. Gross-total resection of the tumor was achieved in 10 patients. A subtotal resection of the tumor was achieved in the remaining patient. Two patients had transient postoperative facial nerve palsies, 1 patient developed a new CN XI palsy postoperatively, and 5 patients experienced transient hoarseness and difficulty swallowing. Two patients required a tracheotomy because they demonstrated dysfunction of the caudal CNs and subsequently developed postoperative pneumonia. Postoperatively, 5 patients required the temporary placement of a nasogastric feeding tube. There were no surgery-related deaths in this series. CONCLUSIONS: The modified far-lateral transcondylar approach is an effective treatment for HGNs, yielding a high total tumor removal rate with an acceptable rate of morbidity.

Two-bone flap craniotomy for the transpetrosal-presigmoid approach to avoid a bony defect in the periauricular area after surgery on petroclival lesions: technical note.

The authors describe a two-bone-flap craniotomy technique to avoid the bone defect caused by the transpetrosal-presigmoid approach. Briefly, this technique includes three steps. The first step is to elevate a temporoparietal bone flap located superiorly to the transverse and sigmoid sinuses. The second step is to dissect the transverse and sigmoid sinuses away from the bone by inserting a gelatin sponge. This maneuver provides hemostasis and protects the sinuses from injury. The third step is to cut a second bone flap including part of the temporal bone and the outer table of the mastoid bone with a high-speed drill system. After the operation, the two bone flaps are fixed in place with titanium osteosynthesis fixation material. This approach provides a simple, easy, and safe technique for the transpetrosal-presigmoid approach. The technique has been performed in 83 patients treated for petroclival neoplasms with excellent cosmetic results.