Endoscopic Approach to Remove Intra-extracranial Tumors in Various Skull Base Regions: 10-year Experience of a Single Center.

BACKGROUND: Some problems have been found in the usually adopted combined approach for the removal of intra-extracranial tumors in skull base. Herein, we described a pure endoscopic transnasal or transoral approach (ETA) for the removal of intra-extracranial tumors in various skull base regions. METHODS: Retrospectively, clinical data, major surgical complications, pre- and postoperative images, and follow-up information of a series of 85 patients with intra-extracranial tumors in various skull base regions who were treated by surgery via ETA in our skull base center during the past 10 years were reviewed and analyzed. RESULTS: Gross total tumor removal was achieved in 80/85 cases (94.1%) in this study. All 37 cases with tumors in anterior skull base and all 14 cases with tumors in jugular foramen received total tumor removal. Thirteen and three cases with tumors in clivus received total and subtotal tumor removal, respectively. Total and subtotal tumor removal was performed for 16 cases and 2 cases in lateral skull base, respectively. The complications in this study included: cerebrospinal fluid leakage (n = 3), meningitis (n = 3), and new cranial nerve deficits (n = 3; recovered in 3 months after surgery). In the follow-up period of 40-151 months (median: 77 months), seven patients (8.8%) out of the 80 cases of total tumor removal experienced recurrence. CONCLUSIONS: Complete resection of intra-extracranial growing tumors in various skull base regions can be achieved via the pure ETA in one stage in selected cases. Surgical procedure for radical removal of tumors is feasible and safe.

Usefulness of intraoperative electromyographic monitoring of oculomotor and abducens nerves during skull base surgery.

BACKGROUND: Intraoperative neurophysiologic monitoring of the extraocular cranial nerve (EOCN) is not commonly performed because of technical difficulty and risk, reliability of the result and predictability of the postoperative function of the EOCN. METHODS: We performed oculomotor nerve (CN III) and abducens nerve (CN VI) intraoperative monitoring in patients with skull base surgery by recording the spontaneous muscle activity (SMA) and compound muscle action potential (CMAP). Two types of needle electrodes of different length were percutaneously inserted into the extraocular muscles with the free-hand technique. We studied the relationships between the SMA and CMAP and postoperative function of CN III and CN VI. RESULTS: A total of 23 patients were included. Nineteen oculomotor nerves and 22 abducens nerves were monitored during surgery, respectively. Neurotonic discharge had a positive predictive value of less than 50% and negative predictive value of more than 80% for postoperative CN III and CN VI dysfunction. The latency of patients with postoperative CN III dysfunction was 2.79 ± 0.13 ms, longer than that with intact CN III function (1.73 ± 0.11 ms). One patient had transient CN VI dysfunction, whose CMAP latency (2.54 ms) was longer than that of intact CN VI function (2.11 ± 0.38 ms). There was no statistically significant difference between patients with paresis and with intact function. CONCLUSIONS: The method of intraoperative monitoring of EOCNs described here is safe and useful to record responses of SMA and CMAP. Neurotonic discharge seems to have limited value in predicting the postoperative function of CN III and CN VI. The onset latency of CMAP longer than 2.5 ms after tumor removal is probably relevant to postoperative CN III and CN VI dysfunction. However, a definite quantitative relationship has not been found between the amplitude and stimulation intensity of CMAP and the postoperative outcome of CN III and CN VI.

Trigeminal neuralgia caused by a dilated superior cerebellar artery and a draining vein of cerebellar arteriovenous malformations: a case report and review of the literature.

Trigeminal neuralgia (TN) secondary to arterivenous malformations (AVMs) is relatively rare. We here report on a case of TN caused by cerebellar AVMs that was successfully treated by total AVMs resection in conjunction with microvasecular decompression (MVD) in one stage. In addition, we perform a review of the literature about the treatment of TN caused by cerebellar AVMs.

Identification of cranial nerves around trigeminal schwannomas using diffusion tensor tractography: a technical note and report of 3 cases.

BACKGROUND: There are no large series studies identifying the locations of cranial nerves (CNs) around trigeminal schwannomas (TSs); however, surgically induced cranial neuropathies are commonly observed after surgeries to remove TSs. In this study, we preoperatively identified the location of CNs near TSs using diffusion tensor tractography (DTT). METHODS: An observational study of the DTT results and intraoperative findings was performed. We preoperatively completed tractography from images of patients with TSs who received surgical therapy. The result was later validated during tumorectomy. RESULTS: A total of three consecutive patients were involved in this study. The locations of CNs V-VIII in relation to the tumor was clearly revealed in all cases, except for CN VI in case 3.The predicted fiber tracts were in agreement with intraoperative observations. CONCLUSIONS: In this study, preoperative DTT accurately predicted the location of the majority of the nerves of interest. This technique can be applied by surgeons to preoperatively visualize nerve arrangements.

Identification of cranial nerves near large vestibular schwannomas using superselective diffusion tensor tractography: experience with 23 cases.

BACKGROUND: The preservation of the facial nerve (FN) and acoustic function in large vestibular schwannoma (VS) surgery is challenging because of nerve course uncertainties and morphological deviations. Preoperative diffusion tensor tractography (DTT) has been proposed to predict the FN location. This study was conducted to evaluate the effectiveness of this technique for identifying the FN, cochlear nerve (CN) and trigeminal nerve (TN) in large VSs. METHODS: The study included 23 consecutive patients with VS of Hannover classification T3b to T4b from November 2013 through May 2014. Diffusion tensor images and anatomical images were acquired. The DTT images of the cranial nerves were extracted before surgery for each patient to determine the relationships of these nerves with the tumor. The results were then validated during the tumorectomy. RESULTS: In 21 (91.30%) patients, the location of the FN on the DTT images agreed with the intraoperative findings, including in 2 patients in whom the FN passed through the interface between the parenchyma and the cystic changes and in 3 patients with a membranoid FN. The CN or fibers of unclear function were observed on DTT images in four patients with functional hearing. One penetrating fiber of unknown function was effectively constructed. The TN was accurately detected on the DTT images for all patients. CONCLUSIONS: DTT effectively revealed the location of the FN, including cases in which the FN was membranoid or passed through the interface between an area exhibiting cystic changes and the tumor nodule. Fibers aside from the FN and the TN were revealed by DTT in patients who retained functional hearing. Penetrating fibers were also found using DTT. This technique can be useful during VS resection.

Cerebral vasculopathy in a Chinese family with neurofibromatosis type I mutation.

Neurofibromatosis type I (NF1) is a hereditary, autosomal dominant, neurocutaneous syndrome that is attributed to NF1 gene mutation. NF1 has been associated with scoliosis, macrocephaly, pseudoarthrosis, short stature, mental retardation, and malignancies. NF1-associated vasculopathy is an uncommon and easily-overlooked presentation. Examination of a Chinese family affected by NF1 combined with cerebral vessel stenosis and/or abnormality suggested a possible relationship between NF1 and vessel stenosis. To determine which NF1 gene mutation is associated with vascular lesions, particularly cerebral vessel stenosis, we examined one rare family with combined cerebral vessel lesions or maldevelopment. Vascular lesions were detected using transcranial Doppler sonography and digital subtraction angiography in family members. Next, denaturing high-performance liquid chromatography and sequencing were used to screen for NF1 gene mutations. The results revealed a nonsense mutation, c.541C>T, in the NF1 gene. This mutation truncated the NF1 protein by 2659 amino-acid residues at the C-terminus and co-segregated with all of the patients, but was not present in unaffected individuals in the family. Exceptionally, three novel mutations were identified in unaffected family members, but these did not affect the product of the NF1 gene. Thus the nonsense mutation, c.541C>T, located in the NF1 gene could constitute one genetic factor for cerebral vessel lesions.

[Surgery for jugular foramen schwannomas via a pure endoscopic transoral approach].

OBJECTIVE: To report a new approach, endoscopic transoral approach for the resection of jugular foramen schwannoma. METHODS: Nine patients with jugular foramen schwannoma (three males and six females, ranging in age from 15 to 61 years old) were treated by direct surgery via a pure endoscopic transoral approach to the jugular foramen. Eight patients complained of hypoglossal nerve palsy with hemiatrophy of the tongue; six cases complained of vagus nerve palsy. Three cases complained of glossopharyngeal nerve palsy, one case complained of facial nerve palsy and hearing loss. RESULTS: The nerves in this area were preserved and radical intracapsular removal of the tumor was performed via endoscopic transoral approach in the nine cases. Tumor removal, as assessed by intraoperative endoscopic inspection, postoperative magnetic resonance imaging and clinical evaluation, revealed all tumors were completely removed. One patient suffered from temporary swallowing difficulties and temporary right vagus palsy 1 day after surgery. There were no others intraoperative and postoperative complications. All patients were followed up for 4 - 29 months, no recurrences were occurred in all these patients and the muscle bulk, motor and the pre-postoperative swallowing function, the vagus palsy, the facial nerve palsy and hearing loss had improved in these patients. CONCLUSION: The endoscopic transoral approach and intracapsular removal of the tumor provided for successful minimally invasive surgery in the jugular foramen schwannomas.

Possible novel roles of poly(rC)-binding protein 1 in SH-SY5Y neurocytes: an analysis using a dynamic Bayesian network.

OBJECTIVE: Poly(rC)-binding protein 1 (PCBP1) belongs to the heterogeneous nuclear ribonucleoprotein family and participates in transcriptional and translational regulation. Previous work has identified transcripts targeted by both knockdown and overexpression of PCBP1 in SH-SY5Y neuroblastoma cells using a microarray or ProteomeLab protein fractionation 2-dimensions (PF-2D) and quadrupole time-of-flight mass spectrometer. The present study aimed to further determine whether these altered transcripts from major pathways (such as Wnt signaling, TGF-ß signaling, cell cycling, and apoptosis) and two other genes, H2AFX and H2BFS (screened by PF-2D), have spatial relationships. METHODS: The genes were studied by qRT-PCR, and dynamic Bayesian network analysis was used to rebuild the coordination network of these transcripts. RESULTS: PCBP1 controlled the expression or activity of the seven transcripts. Moreover, PCBP1 indirectly regulated MAP2K2, FOS, FST, TP53 and WNT7B through H2AFX or regulated these genes through SAT. In contrast, TP53 and WNT7B are regulated by other genes. CONCLUSION: The seven transcripts and PCBP1 are closely associated in a spatial interaction network.

The cortical and striatal gene expression profile of 100 hz electroacupuncture treatment in 6-hydroxydopamine-induced Parkinson's disease model.

Electroacupuncture (EA), especially high-frequency EA, has frequently been used as an alternative therapy for Parkinson disease (PD) and is reportedly effective for alleviating motor symptoms in patients and PD models. However, the molecular mechanism underlying its effectiveness is not completely understood. To implement a full-scale search for the targets of 100 Hz EA, we selected rat models treated with 6-hydroxydopamine into the unilateral MFB, which mimic end-stage PD. High-throughput microarray analysis was then used to uncover the regulated targets in the cortex and striatum after 4-week EA treatment. In the differentially regulated transcripts, the proportion of recovered expression profiles in the genes, the functional categories of targets in different profiles, and the affected pathways were analyzed. Our results suggested that the recovery of homeostasis in the transcript network and many regulated functional clusters in the cortex and striatum after EA treatment may contribute to the behavioral improvement of PD rats.

[Serum levels of interferon-γ, interleukin-6 and tumor necrosis factor-α in patients with cerebral arterial stenosis].

OBJECTIVE: To investigate the relationship between interferon-γ(IFN-γ), interleukin-6(IL-6), tumor necrosis factor-α(TNF-α) and cerebral arterial stenosis and to compare serum levels of these inflammatory cytokines in different cerebral arteries stenosis groups. METHODS: According to the stenotic site, patients with cerebral arteries stenosis were divided into intracranial stenosis group (n=26), extracranial stenosis group (n=30), intracranial and extracranial stenosis group (n=27), and group of stenosis in middle cerebral artery (n=25). And there were 33 samples in the control group. Blood serum IFN-γ, IL-6 and TNF-α levels were analyzed using enzyme linked immunosorbent assays (ELISA). RESULTS: Serum IFN-γ and IL-6 levels were significantly increased in all the stenosis groups (P=0.000) as compared with the control group. But serum IFN-γ level had no significant difference between the two optional stenosis groups. And IL-6 level in intracranial stenosis group was lower than those in the other stenosis groups (P<0.05). In addition, we found that TNF-α of intracranial stenosis group (P=0.001) and MCA stenosis group (P=0.015) significantly increased as compared with the control group and the other two stenosis groups. CONCLUSION: The results suggest that IFN-γ, IL-6 and TNF-α are possible to participate in the formation of certain cerebral arterial stenosis.

Management and prognosis of symptomatic patients with intramedullary spinal cord cavernoma: clinical article.

OBJECT: The authors conducted a study to assess the clinical pattern, radiological features, therapeutic strategies, and long-term outcomes in patients with intramedullary spinal cord cavernomas (ISCCs) based on a large case series. METHODS: This retrospective study identified 96 patients (60 males, 36 females) surgically (81 cases) or conservatively (15 cases) treated for ISCCs between May 1993 and November 2007. Each diagnosis was based on MR imaging and spinal angiography evidence. For all surgically treated patients, the diagnosis was verified pathologically. The neurological outcomes pre- and postoperatively, as well as long-term follow-up, were assessed using the Aminoff-Logue Disability Scale. RESULTS: The mean age at the onset of symptoms was 34.5 years (range 9-80 years). Of the lesions, 68 (71%) were located in the thoracic spine, 25 (26%) in the cervical spine, and only 3 (3%) in the lumbar spine. The median symptom duration was 19.7 months. The clinical behavior of the lesion was a slow progression in 73 cases and an acute decline in 23 cases. Long-term follow-up data (mean 45.8 months, range 10-183 months) were available for 75 patients (64 surgical cases and 11 conservative cases). In the surgical group, a complete resection was achieved in 60 patients, and incomplete resection was detected in 4 patients after operation. At the end of the follow-up period in the operative group, 23 patients (36%) improved, 35 (55%) remained unchanged, and 6 (9%) worsened. In the nonoperative group, 5 patients improved, 6 patients remained unchanged, and none worsened. CONCLUSIONS: For differential diagnosis, spinal angiography was necessary in some cases. For most symptomatic lesions, complete microsurgical resection of the symptomatic ISCC is safe and prevents rebleeding and further neurological deterioration. However, in patients whose lesions were small and located ventrally in the spinal cord, one can also opt for a rigorous follow-up, considering the high surgical risk.

Intracranial aneurysms in adolescents.

PURPOSE: Intracranial aneurysms are extremely uncommon in adolescents. This study was undertaken to assess the clinical and radiological characteristics and clarify the choice of therapeutic strategies of intracranial aneurysms in adolescents with age range from 15 to 18 years. METHODS: From our dedicated aneurysmal databank between October 1985 and July 2008, we reviewed 16 consecutive adolescents who had 20 intracranial aneurysms. RESULTS: Ten boys and six girls (male/female ratio = 1.67:1; mean age 16.78 ± 1.18 years) were included in the present study. Intracranial aneurysms in adolescents constituted 0.91% of all intracranial aneurysms. It was found that 25% of the lesions were in the posterior circulation, while 75% of the lesions were in the anterior circulation, and 25% developed on the middle cerebral artery (MCA). Half of the patients presented with subarachnoid hemorrhage and others mainly presented with mass effect such as weakness in the extremities, diplopia, and dysfunction of eye movement. Eight cases underwent endovascular treatment: including GDC therapy in five patients, parental artery occlusion in two patients, and cover stent implantation in one patient with pseudoaneurysm of the cavernous segment of the left internal carotid artery. Four patients received microsurgical therapy: aneurismal neck clipping for two patients and extracranial-intracranial (EC-IC) bypass and trapping of complex aneurysms in MCA for the other two patients. Four patients did not receive microsurgical or endovascular therapy, including a boy whose aneurysm spontaneously thrombosed preoperatively and a girl who died before operation because of rerupture of aneurysm. Two patients did not undergo therapy owing to the high operative risk. All of the patients who received therapy had favorable outcome (GOS 4 or 5) at discharge and at follow-up. CONCLUSIONS: Intracranial aneurysms in adolescents differ from those in adults in many ways including the following: male predominance; high incidence of large or giant, traumatic, dissecting, and fusiform aneurysms; high incidence of aneurysms in the posterior circulation; high incidence of spontaneous thrombosis; better Hunt-Hess grade at presentation; and better therapeutic outcome. Both microsurgical approaches and endovascular treatment were effective. For some giant, complex intracranial aneurysms, parent artery occlusion or EC-IC bypass is the best treatment choice.

[Intracranial aneurysms in childhood and adolescence].

OBJECTIVE: To assess the radiological characteristics and therapeutic strategies of intracranial aneurysms in childhood and adolescence. METHODS: From our dedicated aneurysmal patient databank, the investigators reviewed 39 consecutive children and adolescents with 44 intracranial aneurysms. There were 24 boys and 15 girls. RESULTS: Twenty-two patients underwent endovascular treatment. Among them, 8 patients received microsurgical therapy. Aneurysms became spontaneously thrombosed before therapy in 3 patients. One patient died pre-operatively from a re-rupture of aneurysm. And 5 cases were not treated at all. CONCLUSION: Intracranial aneurysms in childhood and adolescence have many clinical and radiological characteristics: (1) remarkable male predominance; (2) middle cerebral artery is the most common site for aneurysms; (3) there is a high prevalence of giant, traumatic, dissecting and fusiform aneurysms; (4) both microsurgical approaches and endovascular treatment were effective. For some giant complex intracranial aneurysms, parent arterial occlusion or EC-IC (extracranial-intracranial) bypass is the best therapeutic choice. A majority of patients may have favorable outcomes.