Volume 122  ·  Issue 20  ·  2009

Translational medicine, normally refers to a process for transitioning from the initial lab discovery to the patient's bedside with minimal disconnect and offers a comprehensive review of statistical design and methodology. It has been advocated repeatedly by worldwide medical scientists as the new prospect highlighting the transition for scientific achievements from laboratory results to clinical application in recent years. As for neurosurgery, it is generally acknowledged that it has been improving in basic research and clinical practice by bounds and leaps; however, the achievements in basic and clinical neurosurgical studies seem to be parallel with no intersection for mutual interaction.Minimally invasive neurosurgery is aimed at serving as the intersection platform for translational medicine。

Abstract：Background MicroRNAs (miRNAs) are small noncoding regulatory RNAs whose aberrant expression may be observed in many malignancies. However, few data are yet available on human primary medulloblastomas. This work aimed to identify that whether miRNAs would be aberrantly expressed in tumor tissues compared with non-tumorous cerebellum tissues from same patients, and to explore a possible role during carcinogenesis.Methods A high throughput microRNA microarray was performed in human primary medulloblastoma specimens to investigate differentially expressed miRNAs, and some miRNAs were validated using real-time quantitative RT-PCR method. In addition, the predicted target genes for the most significantly down-or up-regulated miRNAs were analyzed by using a newly modified ensemble algorithm.Results Nine miRNA species were differentially expressed in medulloblastoma specimens versus normal non-tumorous cerebellum tissues. Of these, 4 were over expressed and 5 were under expressed. The changes ranged from 0.02-fold to 6.61-fold. These findings were confirmed using real-time quantitative RT-PCR for most significant deregulated miRNAs (miR-17, rniR-lO0, miR-lO6b, and miR-218) which are novel and have not been previously published. Interestingly, most of the predicted target genes for these miRNAs were involved in medulloblastoma carcinogenesis.Conclusions MiRNAs are differentially expressed between human medulloblastoma and non-tumorous cerebellum tissue. MiRNAs may play a role in the tumorigenesis of medulloblastoma and maybe serve as potential targets for novel therapeutic strategies in future。

Abstract：Background Standard superficial temporal artery-middle cerebral artery (STA-MCA) bypass surgery is an effective treatment for moyamoya disease, but recent evidence suggests that postoperative cerebral hyperperfusion can occur. In this study, the trendline of changes in regional cerebral blood flow (rCBF) after surgery were continually monitored near the site of anastomosis in order to investigate both the efficacy of the procedure for improving rCBF and the possible riskof hyperperfusion.Methods Standard STA-MCA bypass surgery was performed on 13 patients, rCBF was measured continually using laser Doppler flowmetry (LDF) until the 5th day after the operation with the LDF probe implanted adjacent to the area of the anastomosis. The trendline of rCBF changes postoperatively was recorded for the analysis performed using SPSS 13.0.Results The baseline LDF value of cortical rCBF was (84.68±14.39) perfusion unit (PU), which was linear relative to absolute perfusion volume before anastomosis and (88.90±11.26) PU immediately after anastomosis (P >0.05). The value changed significantly from before to after anastomosis (P <0.05); it was (417.72±21.35) PU on the 1st day after surgery, and (358.99±18.01) PU, (323.46±17.38) PU, (261.60±16.38) PU and (375.72±18.45) PU on the following 4 days,respectively. The rCBF decreased gradually from the 2nd day until the 4th postoperative day, but still was at a high level (P<0.05). However, on the 5th postoperative day the rCBF increased again to the second highest level, which was significantly different compared with the baseline value (P<0.05), but not significantly different compared with the values on the other 4 days (P>0.05).Conclusions STA-MCA anastomosis improves the cerebral blood supply significantly in the early stage after surgery,however, the risk of symptomatic hyperperfusion may exist, which may possibly occur on the 1st day and 5th day after surgery. A LDF is useful for postoperative monitoring for both the efficacy of bypass and possible risk of neurologic deterioration or bleeding from hyperperfusion。

Abstract：Background Subthalamic deep brain stimulation (STN-DBS) has been shown to be effective in the treatment of Parkinson's disease. The site for permanent sti mulation is still in debate. This study aimed to assess the position of active contacts in relation to the subthalamic nucleus.Methods We reviewed the location of 40 electrodes in 34 patients who underwent STN-DBS. The position of electrode was evaluated by postoperative magnetic resonance imaging (MRI). The position of active contacts was compared with the subthalamic nucleus (STN) determined by intraoperative electrophysiological mapping and postoperative MRI.Results The average position of the 40 active contacts was (11.7±1.2) mm lateral, (0.6±1.3) mm anterior, and (0.7±1.4)mm vertical to the midcommissural point. The dlorsal margin of the STN was (11.6±1.1) mm lateral, (0.2±1.1) mm anterior,and (1.3±1.1) mm vertical to the midcommissural point. When compared with the dorsal margin of the STN, the active contacts were located more dorsally (P=0.033) and anteriorly (P=0.012), no significant difference was found in the lateral direction (P=0.107). When compared with the Position of the STN, 26 (65%) of active contacts were located in the region dorsal to the STN, only 13 (32.5%) were located in the upper two-thirds portion of STN.Conclusions The site for permanent stimulation appears to be in the subthalamic region dorsal to the STN, close to the dorsal margin of the STN. Besides the dorsal portion of the STN, other structures such as fields of Forel H and zona incerta may also be involved in the therapeutic benefit of deep brain stimulation。

Abstract：Background Sphenoid wing meningioma en plaque is a special morphological subgroup of intracranial meningiomas,defined by a carpet-like, soft tissue component that infiltrates the dura and invades the sphenoid wing and orbit associated with a significant hyperostosis. This report summarized our experiences in 37 patients with sphenoid wing meningioma en plaque who had been treated with transcranio-orbital approach surgery.Methods A retrospective study was made on clinical manifestations, neuroradiological features, and operative techniques in 37 patients undergoing transcranio-orbital approach from Sep. 1998 to Apr. 2009. Patients ages: 16 years to 67 years, 45.5 years in average; sex: 15 males, 22 females. Chief complaints were progressive proptosis and visual acuity deficits. All patients were operated on using a fronto-temporal approach with orbital decompression. The extent of tumor resection and postoperative complications were investigated.Results Simpson grade Ⅱ resection was achieved in 9 patients, Simpson grade Ⅲ in 22 patients and Simpson grade IV in 6 patients. Pathological examination showed 27 (73%) patients were meningothelial meningiomas. After surgery,proptosis improved in all patients, visual acuity improved in 18 patients (69%). Temporary ophthalmoplegia was found in 8 patients, cerebrospinal fluid leak was found in 1 patient. Duration of follow up was from 3 months to 9 years, tumor recurred in 7 patients, and 5 patients underwent second surgery, including two trans-nasal endoscopic surgeries to resect sphenoid sinus-involved tumor. There were no operation-related deaths or other significant complications.Conclusions Sphenoid wing meningioma en plaque, mainly meningothelial meningiomas, are more likely to produce adjacent hyperostosis and have characteristic radiological appearances. All the hyperostosis bone of the great wing of sphenoid bone should be removed to prevent recurrence. Extensive tumor removal with bony decompression at the orbital apex can produce satisfactory cosmetic and functional outcome. Close co-operation between the neurosurgeons and the ophthalmologists is important。

Abstract：Background In the chronic stage of cerebral venous sinus thrombosis (CVST), recanalization can result in disparate MR appearances. We aimed to prospectively investigate the diagnostic accuracy of magnetic resonance venography (MRV) in the evaluation of the recanalization of CVST.Methods This study prospectively evaluated the diagnostic performance of 2-dimensional time-of-flight (2D-TOF) MRV in thirty-two consecutive patients during a three- to six-month follow-up for CVST. Both 2D-TOF MRV and digital substraction angiography (DSA) were undertaken. Diagnostic accuracy of 2D-TOF MRV in the detection of recanalized thrombus was evaluated using DSA as the reference standard.Results MRV and DSA were completed without complications in all 32 patients. The sensitivity, specificity, positive predictive value, and negative predictive value of 2D-TOF MRV for the detection of recanalization on a segmental basis were 91% (62/68), 93% (37/40), 95% (62/65), and 86% (37/43) respectively.Conclusion 2D-TOF MRV provides high sensitivity and specificity for the diagnosis of recanalized CVST segments。

Abstract：Background Dysembryoplastic neuroepithelial tumor (DNT) is a rare benign neoplasm of the central nervous system affecting young people. A correct preoperative diagnosis is helpful for planning surgical strategies and improving prognosis. The purpose of this study was to characterize DNTs using magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) and to analyze the value of these two techniques in the diagnosis of DNTs.Methods MR images of 13 patients with DNTs were reviewed retrospectively; and five of the patients also underwent MRS. Tumors were confirmed by surgery. The distribution, extension and signal features of the lesions were assessed,and the MRS results were analyzed.Results All tumors were supratentorial. The cortex was the main area involved, with nine tumors located in the temporal lobe, three in the frontal lobe, and one on the boundary between the temporal and occipital lobes. All cases had decreased signal intensity on T1-weighted MR images and increased signal intensity on T2-weighted images. On fluid attenuated inversion recovery weighted images, the hyperintense "ring sign" and internal septation of the lesion were seen in 9 cases. Eight tumors had well-demarcated borders. Peritumoral edema or mass effect was absent in all cases. A contrast enhancement examination was performed in 9 cases. Contrast enhancement was absent in five cases, and four cases showed significant enhancement. The MRS showed a low N-acetylaspartate peak and a lack of elevated choline-containing component (Cho) or Cho-Cr ratio (Cho/Cr) in five patients.Conclusions The MRI findings of DNTs were stereotypical. The combination of MRI and MRS techniques were helpful in making a correct presurgical diagnosis。

Abstract：Background The subthalamic nucleus (STN) is widely recognized as one of the most important and commonly targeted nuclei in stereotactic and functional neurosurgery. The success of STN surgery depends on accuracy in target determination. Construction of a digitalized atlas of STN based on stereotactic MRI will play an instrumental role in the accuracy of anatomical localization. The aim of this study was to investigate the three-dimensional (3D) target location of STN in stereotactic space and construct a digitalized atlas of STN to accomplish the visualization of the STN on stereotactic MRI, thus providing clinical guidance on the precise anatomical localization of STN.Methods One hundred and twenty healthy people volunteered to be scanned by 1.5 Tesla MRI scanning with 1-mm-thick slice in the standard stereotactic space between 2005 and 2006. One adult male was selected for 3D reconstruction of STN. The precess of 3D reconstruction included identification, manual segmentation, extraction,conservation and reconstruction.Results There was a significant correlation between the coordinates and age (P <0.05). The volume of left STN was significantly larger than the right STN, and there was a significant negative correlation between volume and age (P <0.05).The surface of the STN nucleus after 3D reconstruction appeared smooth, natural and realistic. The morphological feature of STN on the individual brain could be visualized directly in 3D. The 3D reconstructed STN could be rotated,zoomed and displayed at any direction in the stereotactic space. The anteroposterior diameter of the STN nucleus was longer than the vertical and transverse diameters in 3D space. The 3D reconstruction of STN manifested typical structure of the "dual lens".Conclusions The visualization of individual brain atlas based on stereotactic MRI is feasible. However, software for automated segmentation, extraction and registration of MR images need to be further developed.

Abstract：Backgroud The expanded endonasal approach (EEA) is used sparingly by surgeons for resection of lesions in the ventrocranial base. Herein, we examined the anatomy of the ventrocranial base by endoscopy and comment on the use of EEA in clinical practice.Methods Twenty artery-injected adult cadaveric heads were studied under surgical conditions using the endoscopic EEA. The extent of the surgical exposure, the endoscopic anatomic view and the maneuverability of surgical instruments about the suprasellar region were studied by the endoscopic EEA.Results The EEA by endoscope can reach the suprasellar region. In this approach, the optocarotid recess, supra and infra-optic chiasm interspace, the ophthalmic artery and others were important anatomical landmarks for identification of the suprasellar region.Conclusions The endoscopic EEA can be used to remove many types of lesions in the ventrocranial base. The microanatorny observed using the endoscope provides important anatomical information on the suprasellar region for neurosurgeons。

Abstract：Background Human amniotic epithelial cells (HAECs) are able to secrete biologically active neurotrophins such as brain-derived neurotrophic factor and neurotrophin-3, both of which exhibit trophic activities on dopamine neurons.Previous study showed that when human amniotic epithelial cells were transplanted into the striatum of 6-hydroxydopamine (6-OHDA)-induced Parkinson disease rats, the cells could survive and exert functional effects. The purpose of this study was to investigate the survival and the differentiation of human amniotic epithelial cells after being transplanted into the lateral ventricle of Parkinson's disease (PD) rats, and to investigate the effects of grafts on healing PD in models.Methods The Parkinson's model was made with stereotactic microinjection of 6-hydroxydopamine (6-OHDA) into the striatum of a rat. The PD models were divided into two groups: the HAECs group and the normal saline (NS) group.Some untreated rats were taken as the control. The rotational asymmetry induced by apomorphine of the HAECs group and the NS group were measured post cell transplantation. The expression of nestin and vimentin in grafts were determined by immunohistology. Ten weeks after transplantation the density of tyrosine hydroxylase positive cells in the substantia nigra of the HAECs group, NS group and the untreated group was determined. The differentiation of grafts was determined by TH immunohistology. High performance liquid chromatography (HPLC) was used to determine monoamine neurotransmitter levels in the striatum.Results The rotational asymmetry induced by apomorphine of the HAECs group was ameliorated significantly compared to the NS group two weeks after transplantation (P <0.01). The grafts expressed nestin and vimentin five weeks after transplantation. TH immunohistochemistry indicated that the TH positive cells in the substantia nigra of the HAECs group increased significantly compared to the NS group (P<0.01). Tyrosine hydroxylase (TH) positive cells in the substantia nigra of the HAEC group and the NS group were decreased compared to the untreated group (P <0.01).Dopamine and DOPAC levels in the striatum of the HAECs group increased significantly compared to the NS group (P <0.05). Homovanillic acid (HVA) levels in the striatum of the HAECs group increased significantly compared to the NS group (P<0.01). In addition dopamine, DOPAC, and HVA levels in the striatum and dopamine levels in the cerebrospinal fluid of the HAECs group and the NS group were decreased compared to the untreated group (P <0.05).Conclusions Human amniotic epithelial cells could be used to ameliorate the rotational asymmetry induced by apomorphine of the PD models. This could have been due to the increased content of dopamine and its metabolic products, DOPAC and HVA, in the striatum in the PD models。

Abstract：Background Cardiac resynchronization therapy (CRT) is a major breakthrough in therapy for advanced heart failure patients; however, a number of key clinical research questions remain, perhaps most importantly the issue of why apparently suitable patients do not respond to CRT.Methods Seven patients, six males and one female, aged (56.43±6.13) years, all diagnosed with dilated cardiomyopathy, were included in this study. They were all non-responders to CRT who underwent routine optimization postoperatively, and received optimal drug therapy. On the basis of biventricular pacing, titrating various atrioventricular (AV) intervals were performed to get the true fusional QRS complexes composed of biventricular pacing and AV intrinsic conduction. Then, the effects of AV intrinsic conduction during CRT were evaluated.Results On the setting of AV intrinsic conduction during CRT, the true fusional QRS complexes were the narrowest, and all patients showed alleviation of symptoms, improvement of exercise tolerance, life quality and hemodynamic parameters during more than 6 months of follow-up.Conclusions Titrating AV intervals to get the true fusional QRS complexes composed of biventricular pacing and AV intrinsic conduction will be beneficial for non-responders to CRT. Maintaining AV intrinsic conduction during CRT may decrease the rates of non-responders to CRT。

Secondary involvement of the adrenal glands with non-Hodgkin's lymphoma (NHL) has been reported to occur in up to 25% of patients during the course of disease.1 However, primary adrenal lymphoma (PAL) is very rare。