Novel patient-derived xenograft and cell line models for therapeutic screening in NF2-associated schwannoma.

Treatment of schwannomas in patients with neurofibromatosis type 2 (NF2) is extremely unsatisfactory, and innovative therapeutic approaches are urgently needed. However, the lack of clinically relevant NF2-associated schwannoma models has severely hampered drug discovery in this rare disease. Here we report the first establishment and characterization of patient-derived xenograft (PDX) and cell line models of NF2-associated schwannoma, which recapitulates the morphological and histopathological features of patient tumors, retain patient NF2 mutations, and maintain gene expression profiles resembling patient tumor profiles with the preservation of multiple key signaling pathways commonly dysregulated in human schwannomas. Using gene expression profiling, we identified elevated PI3K/AKT/mTOR networks in human NF2-associated vestibular schwannomas. Using high-throughput screening of 157 inhibitors targeting the PI3K/AKT/mTOR pathways in vitro, we identified a dozen inhibitors (such as BEZ235, LY2090314, and AZD8055) with significant growth-suppressive effects. Interestingly, we observed that three cell lines displayed differential therapeutic responses to PI3K/AKT/mTOR inhibitors. Furthermore, we demonstrated that two orally bioavailable inhibitors, AZD8055 and PQR309, suppressed NF2-associated schwannoma growth both in vitro and in vivo. In conclusion, our novel patient-derived models of NF2-associated schwannoma closely mimic the phenotypes and genotypes of patient tumors, making them reliable preclinical tools for testing novel personalized therapies. © 2022 The Pathological Society of Great Britain and Ireland.

Management principles of cranial base tumor with aneurysm.

Skull base tumors are challenging to treat because of their deep location, complex anatomy, and close proximity to important blood vessels and nerves. Furthermore, some patients with cranial tumors are found to have aneurysms, but there is no consensus on how to evaluate the impact of aneurysms on surgery and how to handle the lesions safely and effectively. We retrospectively reviewed our database to identify all patients with a skull base tumor treated in the Department of Neurosurgery of Beijing Tiantan Hospital affiliated with Capital Medical University from 2019 to 2021. The records of patients with skull base tumors associated with aneurysms were analyzed. The operative methods and postoperative follow-up information were collected. We analyzed a total of 481 patients with skull base tumors, comprising 224 males and 257 females with a mean age of 48 ± 14 years. Twenty-four patients (24/481, 5.0%) were diagnosed with aneurysms. For eight patients, it was considered necessary to perform aneurysm treatment before or during the tumor resection surgery. For the other 16 patients, the recommendation was to monitor the aneurysm or perform elective aneurysm treatment after tumor resection. All patients with both skull base tumors and aneurysms benefited from treatment. No severe postoperative complications occurred. We summarized the final treatment plan for all patients with skull base tumors with aneurysms and proposed a protocol to decrease the surgical risk of patients with skull base tumors associated with aneurysms.

Surgical outcomes and prognostic factors of parasagittal meningioma: a single-center experience 165 consecutive cases.

PURPOSE: This study aimed to estimate the prognostic factors, long-term outcomes, and surgical strategies for parasagittal meningioma (PSM) and provide a better understanding of surgical experience. MATERIALS AND METHODS: Patients (n = 1438) who underwent surgery for meningioma between January 2012 and January 2013 were enrolled in a database. We then identified 165 patients with PSM based on this database. RESULTS: Of the 165 patients with identified PSMs, 103 were female and 62 were male, with a mean age of 49 years. Univariate analysis revealed that male sex (p = .002), non-World Health Organization (WHO) grade I meningioma (p < .001), treatment history (p = .006), surgical time more than 232 minutes (p = .006), and intraoperative bleeding > 300mL3 (p = .019) were associated with decreased progression-free survival (PFS). Multivariate analysis revealed that sex (hazards ratio [HR] = 3.836, 95% confidence interval [CI] = 1.364-10.794; p = .011], tumour grade (HR = 8.479, 95% CI = 3.234-22.230; p < .001), and surgical time (HR = 3.710, 95% CI = 1.057-13.023; p = .041) were independent factors for PFS. Patients with Simpson grade I-II (p = .015), no-treatment history (p = .006), tumour size < 3cm (p = .005), surgical time < 232 minutes (p = .019), intraoperative bleeding < 300mL3 (p < .001), or WHO grade I meningioma (p = .002) had better follow-up conditions. CONCLUSION: Surgery was an effective treatment for PSM, and at the time of final follow-up, patients who received aggressive resection had a substantially higher Karnofsky performance scale score.

Establishment of nomograms for the prediction of useful hearing loss in patients with neurofibromatosis type 2.

INTRODUCTION: Treatment for vestibular schwannoma (VS) in patients with neurofibromatosis type 2 (NF2) is extremely challenging due to the high risk of hearing loss. The aim of this study was to develop nomograms for the prediction of useful hearing loss in patients with NF2. METHODS: The nomogram was based on a retrospective study of 111 NF2 patients who underwent resection of large VS (> 2 cm) at Beijing Tiantan Hospital between 2011 and 2018. The utility of the proposed nomogram models was evaluated by receiver operating characteristic (ROC) curve, area under ROC curve (AUC), and calibration curve. The results were validated using a prospective cohort study on 33 patients consecutively enrolled at the same institution from 2019 to 2021. RESULTS: On multivariate analysis of the primary cohort, large tumour size (> 3 cm) and long duration of symptoms (> 24 months) were independent risk factors for preoperative useful hearing loss (AAO-HNS Class D) (P = 0.001 and P = 0.011, respectively), while large tumour size (> 3 cm), poor hearing (Class C), and lobular growth were significantly related to postoperative useful hearing loss (P < 0.001, P = 0.031 and P = 0.033, respectively). Factors derived from multivariable analysis were all assembled into the nomogram. The calibration curve for probability of hearing loss showed good agreement between predictions by nomogram models and actual observation. The ROC curves showed good predictive accuracy of the nomogram models in both cohorts (AUC: 0.708 to 0.951). CONCLUSION: The proposed nomograms resulted in accurate predictions of hearing outcomes for patients with NF2.

Internal carotid artery injury during endoscopic transsphenoidal pituitary surgery: risk factors, management.

BACKGROUND: Transsphenoidal surgeons should try to avoid internal carotid artery (ICA) injury but also be prepared to manage it. We analyzed our experience with ICA injury during endoscopic transsphenoidal pituitary surgery and present associated risk factors and a management protocol. METHODS: We retrospectively reviewed and analyzed the medical records of 1596 patients who underwent endoscopic transsphenoidal surgery for pituitary tumor resection in our institution from January 2009 to October 2022. RESULTS: Six patients experienced an ICA injury. All received timely and effective hemostasis with immediate direct tamponade followed by endovascular treatment. No serious postoperative complications occurred. CONCLUSIONS: We proposed a treatment plan for ICA injuries encountered during endoscopic transsphenoidal surgery and described our hemostasis process, methods of endovascular treatment, and means of postoperative follow-up in detail.

Phase II trial of icotinib in adult patients with neurofibromatosis type 2 and progressive vestibular schwannoma.

OBJECTIVE: Neurofibromatosis type 2 (NF2) is a rare autosomal dominant syndrome associated primarily with bilateral vestibular schwannomas (VSs). Conventional surgical or radiosurgical treatments for VS in NF2 usually result in high risks of hearing loss and facial nerve impairment, while there is no validated medical option to date. This single-institution phase II study evaluated the efficacy and safety of icotinib, an oral epidermal growth factor receptor tyrosine kinase inhibitor, in patients with NF2 and progressive VS. METHODS: Icotinib was administered daily at 375 mg orally in a continuous 28-day course for up to 12 courses. The primary endpoint of the study was radiographic response assessed by brain MRI using 3D volumetric tumor analysis and defined as a ≥ 20% decrease in VS volume. Hearing function was evaluated as a secondary endpoint, with response defined as a statistically significant increase in word recognition scores. RESULTS: Ten eligible patients with a mean age of 23.8 years were enrolled. One patient (10%) with bilateral tumors experienced an objective radiographic response (-23.58% and -22.01%). Three (43%) of 7 patients met the hearing response criteria. At 12 months, the estimated progression-free survival was 82.0% (95% CI 42.3%-95.5%) for volumetric progression and 69.2% (95% CI 37.3%-87.2%) for hearing progression. Common mild to moderate adverse events included rash (90%), diarrhea (50%), myalgia (20%), and nausea/gastrointestinal pain (20%). CONCLUSIONS: Icotinib carries minor toxicity and is associated with radiographic and hearing responses in patients with NF2 and progressive VS.

Qu-Du-San-Jie decoction induces growth inhibition and vascular normalization in NF2-associated vestibular schwannoma.

Background: Neurofibromatosis type 2 (NF2) is a rare genetic syndrome that predisposes individuals to develop bilateral vestibular schwannomas (VSs) causing a high risk of life-threatening neurological complications. Traditional treatment options for NF2-associated VS usually cause neurological damage, and to date, there are no FDA-approved pharmacotherapies for NF2. The aim of this study was to evaluate the antitumor efficacy of Qu-Du-San-Jie (QDSJ) decoction, a traditional Chinese medicine formula, on NF2-associated VS and to investigate the potential underlying mechanisms. Methods: Ultra high-performance liquid chromatography-mass spectroscopy (UHPLC-MS) analysis was performed to identify the components of QDSJ and their targets. To determine the relationships between the putative targets of QDSJ and the differential genes of NF2-associated VS, the drug-disease crossover genes were screened using the UHPLC-MS data combined with our previous gene expression profiling data. The differentially expressed genes were imported into the STRING database to generate a PPI network. Differentially expressed gene targets and pathways were identified using GO and KEGG pathway enrichment analyses. The in vitro and in vivo drug efficacy of QDSJ decoction was tested using a patient-derived schwannoma cell line and a patient-derived xenograft mouse model, respectively. H&E staining, immunochemistry, and immunofluorescence staining were used to evaluate the cell proliferation and tumor vessels. Results: A total of 133 compounds were identified in QDSJ decoction using UHPLC-MS analysis. Network pharmacology showed that the regulation of necroptosis, apoptosis, cell cycle, angiogenesis, adherens junction, and neuroactive ligand-receptor interaction could be associated with the efficacy of QDSJ in treating NF2-associated VS. Treatment with QDSJ induced necrotic cell death and apoptosis of schwannoma cells in vitro and suppressed the tumor growth in vivo. Histopathological analysis revealed areas of cell necrosis and enlarged tumor blood vessels in the QDSJ-treated tumors. The numbers of cells positive for Cyclin D1 and Ki-67 were significantly reduced in QDSJ-treated tumors compared to control tumors. Immunofluorescence staining of CD31 and αSMA showed a decreased number and density of tumor vessels and normalized vessel structure in QDSJ-treated tumors. Conclusion: Our study demonstrates that QDSJ decoction shows significant antitumor activity against NF2-associated schwannoma and is a possible candidate for future clinical trials.

Survival and Prognostic Factors of Adult Intracranial Ependymoma: A Single-institutional Analysis of 236 Patients.

Adult intracranial ependymomas (EPNs) are extremely rare brain tumors. Currently, clinical and molecular factors that could inform individualized treatment strategies are still lacking for EPNs in this age group. The aim of this study was to investigate potential prognostic indicators and rational therapeutic management in a large cohort of adult intracranial EPNs. Adult patients who underwent resection of World Health Organization (WHO) grade II or III intracranial EPNs were included. The demographic features, clinicopathologic manifestations, molecular subgroups, and outcomes were retrospectively analyzed. Overall survival and progression-free survival were calculated using the Kaplan-Meier analysis. Potential prognostic indicators were identified using multivariable Cox proportional hazards model. This cohort included 236 adult patients with a mean age of 36.2 years (range: 18 to 72 y) at diagnosis. The tumor location was supratentorial (ST) in 102 (43.2%) and infratentorial in 134 (56.8%). Pathologic analysis revealed 43.1% of ST-EPNs with RELA fusion and 88.1% of posterior fossa ependymomas (PF-EPNs) with positive H3K27me3 staining. Gross total removal was achieved in 169 cases (71.6%). During follow-up, 97 (41.1%) patients had disease progression and 39 (16.5%) died. Kaplan-Meier analysis showed that patients with H3K27me3-positive PF-EPN had excellent survival, whereas patients with RELA fusion-positive ST-EPN or H3K27me3-negative PF-EPN had poor prognosis (progression-free survival: P=1.3E-16, overall survival: P=2.5E-12). Multivariate analysis showed that molecular subgroup, extent of resection, and Ki-67 index were strong independent prognostic indicators. In conclusion, our study provides essential information on the prognostic prediction of adult intracranial EPNs that will assist in establishing appropriate risk stratification and individualized treatment strategies in future clinical trials.

Evolution of transmaxillary approach to tumors in pterygopalatine fossa and infratemporal fossa: anatomic simulation and clinical practice.

BACKGROUND: The endoscopic transnasal approach has been proven to have advantages on the removal of the tumors in pterygopalatine fossa (PPF) and infratemporal fossa (ITF). Herein, this study aimed to describe a modified approach for resection of the tumors in these areas, both in cadaveric specimen and clinical patients. METHODS: The 20 adult cadaveric specimens and five patients with tumors in PPF and ITF were enrolled in this study. For the cadaveric specimens, ten were simulated anterior transmaxillary approach and ten were performed modified endoscopic transnasal transmaxillary approach. The exposure areas were compared between two groups and main anatomic structure were measured. Surgery was operated in the five patients with tumors of PPF and ITF to verify the experience from the anatomy. Perioperative management, intraoperative findings and postoperative complications were recorded and analyzed. RESULTS: The modified endoscopic transnasal transmaxillary approach provided as enough surgical exposure and high operability to the PPF and ITF as the anterior transmaxillary approach did. The diameter of maxillary artery in the PPF was 3.77 ±â€Š0.78 mm (range: 2.06-4.82 mm), the diameter of middle meningeal artery in the ITF was 2.79 ±â€Š0.61 mm (range: 1.54-3.78 mm). Four patients who suffered schwannoma got total removal and one of adenocystic carcinoma got subtotal removal. The main complications were facial numbness and pericoronitis of the wisdom tooth. No permanent complication was found. CONCLUSIONS: With the widespread use of neuroendoscopy, the modified endoscopic transnasal transmaxillary approach is feasible and effective for the resection of tumors located in PPF and ITF, which has significant advantages on less trauma and complications to the patients.

Association of Craniovertebral Junction Anomalies, Klippel-Feil Syndrome, Ruptured Dermoid Cyst and Mirror Movement in One Patient: A Unique Case and Literature Review.

The Klippel-Feil syndrome (KFS) has been reported to be associated with intracranial neoplasms, most frequently epidermoid or dermoid cysts. To our knowledge, however, patients who present with a posterior fossa dermoid cyst (DC) and KFS are extremely rare with only 24 previously reported cases in the English literature worldwide. Therefore, we present the first report of a patient with a craniocervical ruptured DC accompanied by craniovertebral junction (CVJ) anomalies, KFS and mirror movement. Meanwhile, a literature review of KFS accompanying with posterior fossa DC discusses these conditions from the embryological, anatomical, clinical and therapeutic perspectives. Additionally, the combination of CVJ anomalies, KFS and DC may represent a new syndrome that has previously gone unnoticed.

[Clinical application of minimally invasive neuroendoscopic techniques].

OBJECTIVE: To summarize and analyze the application of neuroendoscopic techniques in neurosurgery, and to discuss the role and significance of neuroendoscopic techniques in the diagnosis and treatment of neurosurgical diseases. METHODS: We treated 1300 patients with different neurosurgical diseases by performing endoscopic neurosurgery (EN) and endoscopy-assisted microneurosurgery (EAM). Among 1300 paitents, 522 were treated with pure endoscopic neurosurgery, 260 with endoscopy-assisted microneurosurgery, 79 with endoscope-controlled bur hole trephination neurosurgery, 434 with endoscope transsphenoidial surgery, and 5 with other techniques through which an endoscope was used in conjunction with stereotactic guidance. RESULTS: Totally 362 hydrocephalus patients were treated using EN. Among them, 190 were treated by third ventriculostomy, 30 by V-P shunt, and 142 patients with complicated hydrocephalus and unsymmetry hydrocephalus by endoscopy-controlled pathologic septum fenestration, septum pellucidum fenestration, and treatment of inventricula inflammation. Clinical symptomatic improvement was achieved in 341 of 362 patients (94.2%). Also 160 intracranial cyst patients were treated using EN for resection and partial resection. Eighty-two patients were performed through cyst-ventricula fenestration. Clinical symptomatic improvement was achieved in 76 of 82 patients (92.7%). Seventy patients treated with endoscopy-controlled bur hole neurosurgery and 8 cases with endoscopy-assisted microneurosurgery got better recovery after operation. Among 260 patients with brain tumors, 252 patients were operated with EAM (190 patients with epidermoid cyst), 8 patients with EN (all brain tumors with diameters < 2.5 cm in inventricular). Clinical symptomatic improvement was achieved in 228 of 260 patients (87.7%). Among 49 patients with inventricular and cistern cyst, 40 patients who were treated by EN and 9 patients by endoscopy-controlled bur hole neurosurgery were resected and their clinical symptoms were improved after operation. Among 434 patients with sellar region lesions, 387 patients with pituitary adenomas, 19 patients with repair for CSF leaks, 9 patients with chordoma, and 19 patients with other neurosurgical diseases were performed with endoscopy-controlled transsphenoidial surgery. Clinical symptoms in 88.9% (386/434) of these patients were improved. Another 5 patients were treated with endoscopy combined with navigation and stereotatic guidance with good results. The complications related to operation were found in only 2% of all the patients including hemorrhage, infection, and damage of important structure. CONCLUSIONS: Clinical application of neuroendoscopic techniques can decrease the damage caused by pure open surgery operation. It is possible to resect lesions at the utmost and protect normal tissue from lesions for using EN and EAM or endoscopy-controlled microneurosurgery (ECM). It is also helpful to enhance surgical quality and, reduce the complications.

Auditory Rehabilitation in Rhesus Macaque Monkeys (Macaca mulatta) with Auditory Brainstem Implants.

BACKGROUND: The auditory brainstem implants (ABIs) have been used to treat deafness for patients with neurofibromatosis Type 2 and nontumor patients. The lack of an appropriate animal model has limited the study of improving hearing rehabilitation by the device. This study aimed to establish an animal model of ABI in adult rhesus macaque monkey (Macaca mulatta). METHODS: Six adult rhesus macaque monkeys (M. mulatta) were included. Under general anesthesia, a multichannel ABI was implanted into the lateral recess of the fourth ventricle through the modified suboccipital-retrosigmoid (RS) approach. The electrical auditory brainstem response (EABR) waves were tested to ensure the optimal implant site. After the operation, the EABR and computed tomography (CT) were used to test and verify the effectiveness via electrophysiology and anatomy, respectively. The subjects underwent behavioral observation for 6 months, and the postoperative EABR was tested every two weeks from the 1 st month after implant surgery. RESULT: The implant surgery lasted an average of 5.2 h, and no monkey died or sacrificed. The averaged latencies of peaks I, II and IV were 1.27, 2.34 and 3.98 ms, respectively in the ABR. One-peak EABR wave was elicited in the operation, and one- or two-peak waves were elicited during the postoperative period. The EABR wave latencies appeared to be constant under different stimulus intensities; however, the amplitudes increased as the stimulus increased within a certain scope. CONCLUSIONS: It is feasible and safe to implant ABIs in rhesus macaque monkeys (M. mulatta) through a modified suboccipital RS approach, and EABR and CT are valid tools for animal model establishment. In addition, this model should be an appropriate animal model for the electrophysiological and behavioral study of rhesus macaque monkey with ABI.

Changes in the Vision-related Resting-state Network in Pituitary Adenoma Patients After Vision Improvement.

BACKGROUND: The aim of this research was to investigate the changes in the vision-related resting-state network (V-RSN) in pituitary adenoma (PA) patients after vision improvement, which was induced by operative treatment. METHODS: Ten PA patients with an improved visual acuity or/and visual field after transsphenoidal pituitary tumor resection were recruited and underwent a complete neuro-ophthalmologic evaluation, as well as an magnetic resonance imaging (MRI) protocol, including structural and resting-state functional MRI sequences before and after the operation. The regional homogeneity (ReHo) of the V-RSN was evaluated. Two sample t-test was performed to identify the significant differences in the V-RSN in the PA patients before and after transsphenoidal pituitary tumor resection. RESULTS: Compared with the preoperation counterparts, the PA patients with improved vision after the operation exhibited reduced ReHo in the bilateral thalamus, globus pallidus, caudate nucleus, putamen nucleus, supplementary motor area, and left hippocampal formation, and increased ReHo in the bilateral cuneus gyrus, calcarine gyrus, right lingual gyrus, and fusiform gyrus. CONCLUSIONS: PA patients with improved vision exhibit increased neural activity within the visual cortex, but decreased neural activity in subareas of the multisensory and multimodal systems beyond the vision cortex.

Effect of basic fibroblast growth factor and transforming growth factor ß1 on the healing of reconstructed dura by carbon dioxide laser soldering in minipigs.

BACKGROUND: Carbon dioxide (CO2) laser soldering is an alternative technique for tissue bonding. Basic fibroblast growth factor (bFGF) and transforming growth factor ß(1) (TGFß(1)) are two key factors for wound healing. This study was performed to demonstrate the efficacy of CO2 laser soldering for dural reconstruction and the effect of bFGF and TGFß(1) on healing. METHODS: In Part I, 10 minipigs were randomized into two equal groups. Dural defects were reconstructed by conventional fibrin glue bonding (group I(a)) or CO2 laser soldering (group I(b)). The reconstructed dura was subjected to burst pressure (BP) measurement and immunohistochemical staining after 1 week. In Part II, 36 minipigs were randomized into three equal groups. Dural reconstruction was achieved by CO2 laser soldering. Exogenous bFGF (group II(b)) or TGFß(1) (group II(c)) was administered while group II(a) served as a control group. The specimens were subjected to BP measurement after 1, 2, 3, and 4 weeks, respectively. RESULTS: In Part I, the dura specimens displayed positive staining of only bFGF in group I(a) and of both bFGF and TGFß(1) in group I(b). Group I(b) showed higher BP than group I(a) ((98.00 ± 21.41) mmHg vs. (70.80 ± 15.09) mmHg, respectively; P < 0.05). In Part II, BP of group II(c) was significantly higher than that of group II(a) (P < 0.01). The BP of group II(a) trended toward stabilization after 3 weeks of growth, while that of groups II(b) and II(c) trended toward stabilization after 2 weeks of growth. CONCLUSIONS: CO2 laser soldering is a reliable technique for dural reconstruction. The superior healing of dural reconstruction by CO2 laser soldering may be related to higher expression of bFGF and TGFß(1), and CO2 lasers may stimulate their secretion. Exogenous bFGF or TGFß(1) may improve healing by shortening the wound healing time, and exogenous TGFß(1) may improve the tensile strength.

[Surgical treatment to facial nerve paralysis of different pathogeny].

OBJECTIVE: To evaluate the surgical treatment to facial nerve paralysis of different pathogeny. METHOD: Thirty-seven patients were reviewed, including Bell's Palsy (5 patients), temporal bone fracture (20 patients), media otitis (cholesteatoma) (4 patients), facial neuroma and cranio-maxillo-facial operation trauma (8 patients). All the patients were treated by different surgical methods according different pathogeny. RESULT: The mean percentage facial function improvement (House-Brackmann Grade I-II) was 80% to Bell's Palsy and temporal bone fracture, 100% to media otitis (cholesteatoma). Facial function of three patients improved from House-Brackmann Grade IV to III, two patients had no obvious improvement about facial neuroma; three patients improved from Grade V to III, one improved to IV about cranio-maxillo-facial operation trauma. CONCLUSION: Patients of facial nerve paralysis got better curative effect if treated by proper surgical therapy according different pathogeny.

Prevention of postoperative intracranial infection in patients with cerebrospinal fluid rhinorrhea.

BACKGROUND: Intracranial infection is a common postoperative complication of neurosurgery. This study aimed to identify risk factors of postoperative intracranial infection in patients with cerebrospinal fluid rhinorrhea and to suggest proposals for the prevention. METHODS: A total of 167 patients (113 males and 54 males, average age of 34.4 years) with cerebrospinal fluid rhinorrhea operated on by the senior author were retrospectively reviewed. The data collected included etiology, previous history, clinical manifestation, site of bone defect, operative approach, and postoperative complications. Risk factor(s) for postoperative infection were analyzed using the stepwise multiple Logistic regression. RESULTS: Eighteen (10.8%) patients were infected post-operatively. The independent risk factors for infection were the site of defect (RR = 0.508, 95%CI 0.306 - 0.843, P = 0.009) and historical meningitis (RR = 0.290, 95%CI 0.094 - 0.893, P = 0.031). Patients with multiple defects and saddle floor defects had a higher infection rate. The germiculture was positive in 11 patients, and vancomycin was sensitive to all the pathogenesis. Nine infected patients needed lumbar drainage. Ten patients had hyponatremia, and hydrocephalus occurred in two patients with serious trauma. CONCLUSIONS: To prevent the infection, we should pay closer attention to the high-risk patients pre-operation. During the operation, the methods those can improve wound healing, such as using blood-supply materials, reliable fixation, and eliminating dead space are all helpful. Conducting lumbar drainage and choosing effective prophylactic antibiotics in the early postoperative stage for the high-risk patients are methods of postoperative management.

Anterior and middle skull base reconstruction after tumor resection.

BACKGROUND: Surgical management of skull base tumors is still challenging today due to its sophisticated operation procedure. Surgeons who specialize in skull base surgery are making endeavor to promote the outcome of patients with skull base tumor. A reliable skull base reconstruction after tumor resection is of paramount importance in avoiding life-threatening complications, such as cerebrospinal fluid leakage and intracranial infection. This study aimed at investigating the indication, operation approach and operation technique of anterior and middle skull base reconstruction. METHODS: A retrospective analysis was carried out on 44 patients who underwent anterior and middle skull base reconstruction in the Department of Neurosurgery at Beijing Tiantan Hospital between March 2005 and March 2008. Different surgical approaches were selected according to the different regions involved by the tumor. Microsurgery was carried out for tumor resection and combined endoscopic surgery was performed in some cases. According to the different locations and sizes of various defects after tumor resection, an individualized skull base soft tissue reconstruction was carried out for each case with artificial materials, pedicled flaps, free autologous tissue, and free vascularized muscle flaps, separately. A skull base bone reconstruction was carried out in some cases simultaneously. RESULTS: Soft tissue reconstruction was performed in all 44 cases with a fascia lata repair in 9 cases, a free vascularized muscle flap in 1 case, a pedicled muscle flap in 14 cases, and a pedicled periosteal flap in 20 cases. Skull base bone reconstruction was performed on 10 cases simultaneously. The materials for bone reconstruction included titanium mesh, free autogenous bone, and a Medpor implant. The result of skull base reconstruction was satisfactory in all patients. Postoperative early-stage complications occurred in 10 cases with full recovery after conventional treatment. CONCLUSIONS: The specific characteristics of skull base defects in various regions require different reconstruction materials and methods. The individualized reconstruction based on different skull base defects can achieve satisfactory results.

[Endoscopic endonasal surgery for meningoencephalocele].

OBJECTIVE: To investigate the management experience with transnasal endoscopic technique for meningoencephalocele. METHODS: Nine patients with endonasal encephalomeningocele were managed by transnasal endoscopic surgery, and the skull base defect was repaired by fascia. RESULTS: Eight cases were successfully managed at the time of the first operation, and no relapse case was found during 1 to 4 years follow-up. Only one case of a two years old child relapsed with cerebrospinal fluid rhinorrhea one month after operation. During the second operation, titanium mesh uncovering was found, and replacement of titanium mesh by fascia via skull base defect was done, without relapse one and half years after the second operation. Another case of a one year old child got a fever one day after operation, but no white blood cell was found in the cerebrospinal fluid, and the temperature recovered to normal after release cerebrospinal fluid management. There were no complications of cranial infection, hemorrhage, edema and water retention in brain to be found in all cases. CONCLUSIONS: It is not only minimally invasive, safety and efficiency of transnasal endoscopic technique for meningoencephalocele, but also had a clear operating view for better recolonization of the position of leak and the structure of operating field, therefore, transnasal endoscopic technique is the first choice for the management of endonasal encephalomeningocele. The accurate localization of leak and selection of the appropriate repairing materials are the key point for the successful operation.