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Accurate classification of electrocardiogram (ECG) signals is of significant importance for automatic diagnosis of heart diseases. In order to enable intelligent classification of arrhythmias with high accuracy, an accurate classification method based intelligent ECG classifier using the fast compression residual convolutional neural networks (FCResNet) is proposed. In the proposed method, the maximal overlap wavelet packet transform (MOWPT), which provides a comprehensive time-scale paving pattern and possesses the time-invariance property, was utilized for decomposing the original ECG signals into sub-signal samples of different scales. Subsequently, the samples of the five arrhythmia types were utilized as input to the FCResNet such that the ECG arrhythmia types were identified and classified. In the proposed FCResNet model, a fast down-sampling module and several residual block structural units were incorporated. The proposed deep learning classifier can substantially alleviate the problems of low computational efficiency, difficult convergence and model degradation. Parameter optimizations of the FCResNet were investigated via single-factor experiments. The datasets from MIT-BIH arrhythmia database were employed to test the performance of the proposed deep learning classifier. An averaged accuracy of 98.79% was achieved when the number of the wide-stride convolution in fast down-sampling module was set as 2, the batch size parameter was set as 20 and wavelet subspaces of low frequency bands in MOWPT were selected as input of the classifier. These analysis results were compared with those generated by some comparison methods to validate the superiorities and enhancements of the proposed method.

Among the different arterial accesses, the femoral access is the main approach for intraoperative angiography (IOA) performed in a prone position. Without a standardized protocol, however, the application of prone IOAs in intracranial arteriovenous malformation (AVM) or arteriovenous fistula (AVF) surgery remains limited by its procedural complexity. This study describes the detailed protocol for prone IOA through a transfemoral approach and highlights several refinements in preparing this procedure. This study retrospectively reviewed the intracranial or high cervical AVM/AVF surgical cases in which both resection and IOA were performed in the prone or three-quarter prone position. Extended femoral sheath approaches and radiolucent head clamps were used in all cases. An aneurysm clip, serving as a localization landmark in IOA, was routinely placed within the surgical field. The IOA imaging, clinical impact of IOA, and complications related to the procedure were recorded. A total of six AVM and three AVF cases, operated on in the prone (n = 7) or three-quarter prone (n = 2) positions, were included. Multiple vessel injections were required in 66.7% of cases, and IOA was successfully performed in every intended vessel. All IOA images were adequate for interpretation, except for two cases in which the non-radiolucent component of the head clamp obscured the region of interest in the lateral views. Incomplete occlusion was identified in two patients, and the aneurysm clip provided precise guidance in localizing the residual nidus. Final IOA confirmed complete lesion removal in all cases, and there were no IOA-related complications. Three key steps in setting-up a prone IOA procedure for intracranial AVM/AVF surgery are proposed: (1) utilize an extended femoral sheath approach, (2) establish a localization landmark with an aneurysm clip and (3) avoid possible image interference from the non-radiolucent component of the head clamp.

The classification of electrocardiogram (ECG) signals is very important for the automatic diagnosis of heart disease. Traditionally, it is divided into two steps, including the step of feature extraction and the step of pattern classification. Owing to recent advances in artificial intelligence, it has been demonstrated that deep neural network, which trained on a huge amount of data, can carry out the task of feature extraction directly from the data and recognize cardiac arrhythmias better than professional cardiologists. This paper proposes an ECG arrhythmia classification method using two-dimensional (2D) deep convolutional neural network (CNN). The time domain signals of ECG, belonging to five heart beat types including normal beat (NOR), left bundle branch block beat (LBB), right bundle branch block beat (RBB), premature ventricular contraction beat (PVC), and atrial premature contraction beat (APC), were first transformed into time-frequency spectrograms by short-time Fourier transform. Subsequently, the spectrograms of the five arrhythmia types were utilized as input to the 2D-CNN such that the ECG arrhythmia types were identified and classified finally. Using ECG recordings from the MIT-BIH arrhythmia database as the training and testing data, the classification results show that the proposed 2D-CNN model can reach an averaged accuracy of 99.00%. On the other hand, in order to achieve optimal classification performances, the model parameter optimization was investigated. It was found when the learning rate is 0.001 and the batch size parameter is 2500, the classifier achieved the highest accuracy and the lowest loss. We also compared the proposed 2D-CNN model with a conventional one-dimensional CNN model. Comparison results show that the 1D-CNN classifier can achieve an averaged accuracy of 90.93%. Therefore, it is validated that the proposed CNN classifier using ECG spectrograms as input can achieve improved classification accuracy without additional manual pre-processing of the ECG signals.

Antifriction lubrication is an important research hotspot in the manufacturing field. A high-performance lubricating additive is of great significance for condition monitoring in the metal cutting process system. To improve cutting conditions in manufacturing process, we study the dispersion stability and tribological properties of fullerene nanoparticles in HM32 antiwear lubricating fluid. Fullerene nanoparticles are fully integrated into HM32 antiwear lubricating fluid by electromagnetic stirring and ultrasonic oscillation. The dispersion stability of fullerene nanoparticles in HM32 antiwear lubricating fluid was comprehensively studied by microscope scanning experiment, static sedimentation experiment, and absorption experiment. The four-ball friction experiment was operated to investigate the extreme pressure property and tribological property of lubricating fluids with fullerene concentration ranging from 100 ppm to 1000 ppm. The results show that fullerene nanoparticle can significantly improve the extreme pressure property and wear resistance of HM32 basic lubricating fluid. Meanwhile, we found that an excessively high concentration of fullerene nanoparticles will increase the friction and wear of the four-ball friction pair. The best concentration of fullerene nanoparticles is 200 ppm. When the fullerene concentration reaches 200 ppm, the maximum nonsintering load is significantly increased, and the friction coefficient and the steel ball wear scar diameter are significantly reduced.

The classification of electroencephalogram (EEG) signals is of significant importance in brain-computer interface (BCI) systems. Aiming to achieve intelligent classification of EEG types with high accuracy, a classification methodology using sparse representation (SR) and fast compression residual convolutional neural networks (FCRes-CNNs) is proposed. In the proposed methodology, EEG waveforms of classes 1 and 2 are segmented into subsignals, and 140 experimental samples were achieved for each type of EEG signal. The common spatial patterns algorithm is used to obtain the features of the EEG signal. Subsequently, the redundant dictionary with sparse representation is constructed based on these features. Finally, the samples of the EEG types were imported into the FCRes-CNN model having fast down-sampling module and residual block structural units to be identified and classified. The datasets from BCI Competition 2005 (dataset IVa) and BCI Competition 2003 (dataset III) were used to test the performance of the proposed deep learning classifier. The classification experiments show that the recognition averaged accuracy of the proposed method is 98.82%. The experimental results show that the classification method provides better classification performance compared with sparse representation classification (SRC) method. The method can be applied successfully to BCI systems where the amount of data is large due to daily recording.

This work aimed to investigate miR-93-5p expression in tumor tissue and its in vitro effects in colorectal cancer (CRC) by targeting programmed death ligand-1 (PD-L1). MiR-93-5p and PD-L1 expression was detected in CRC and adjacent normal tissues by quantitative real-time polymerase chain reaction and immunohistochemistry. The correlation between miR-93-5p and PD-L1 was validated by a dual-luciferase reporter assay. HCT116 and SW480 cells were divided into blank, miR-NC, miR-93-5p mimics, miR-93-5p inhibitor, PD-L1 small interfering RNA (siRNA) and miR-93-5p inhibitor + PD-L1 siRNA groups, and wound-healing and transwell assays were performed to detect cell migration and invasion, respectively. Protein expression was measured by western blotting. The secretion of cytokines was detected in the CRC cell/T coculture models. MiR-93-5p was downregulated in CRC tissues with upregulated PD-L1. In PD-L1-negative patients, miR-93-5p expression was increased compared with that in PD-L1-positive patients. MiR-93-5p and PD-L1 expression levels were associated with the tumor differentiation, lymphatic metastasis, TNM, Duke's stage, and prognosis of CRC. PD-L1 siRNA weakened the migration and invasion abilities via decreased expression of matrix metalloproteinase-1 (MMP-1), -2, and -9, and these effects were abolished by the miR-93-5p inhibitor. Additionally, anti-PD-L1 upregulated the expressions of interleukin-2 (IL-2), tumor necrosis factor-α (TNF-α), and interferon γ (IFN-γ) in the coculture of T cells with CRC cells, but downregulated the expressions of IL-1β, IL-10, and TGF-β. However, these changes were partially reversed by miR-93-5p inhibition. miR-93-5p is expected to be a novel target for CRC treatment since it decreases the migration and invasion, as well as the immune evasion, of CRC cells via targeting PD-L1.

Objective Three-dimensional (3D) rotational angiography (RA), a gold standard imaging tool for the evaluation of cerebral aneurysms after clipping, can currently be performed intraoperatively in a hybrid operating room (OR). However, its role in intraoperative aneurysmal surgery is unclear. We aimed to study the value of intraoperative 2-dimensional digital subtraction angiography (2D-DSA) and 3D-RA for the evaluation of aneurysms after clipping, in terms of clip repositioning. Methods We included patients with cerebral aneurysms who were treated with microsurgical clipping in a hybrid OR. After aneurysmal clipping and indocyanine green video angiography assessment, intraoperative 2D-DSA and 3D-RA with volume-rendering (VR) images of the clipped aneurysm were obtained. The incidence rate of clip repositioning was determined, and aneurysm-related factors associated with suboptimal clipping that required clip revision after intraoperative angiography evaluation were analyzed. Results Between September 2016 and August 2017, 24 consecutive patients with 35 aneurysms were treated with microsurgical clipping. A clip repositioning rate of 17.1% was revealed after intraoperative 3D-VR imaging and initial indocyanine green-video angiography. 3D-VR was able to demonstrate all aneurysmal remnants, whereas 2D-DSA helped confirm flow stagnation in compromised vessels. Challenging aneurysms of size >7 mm (P = 0.043) and neck width >4 mm (P = 0.012) were significantly associated with a higher incidence of suboptimal aneurysmal clipping. Conclusions A hybrid OR, with angiography facilities for high-resolution 2D-DSA and 3D-VR images, allows neurosurgeons to perform high-quality surgery. The routine use of intraoperative 3D-RA may not be necessary; however, it is invaluable for treating challenging aneurysms.

Multiple modes of vibration are usually incorporated in a single record of vibration measurement in condition monitoring of rotating machinery. Wavelet transform is an effective tool to detect and isolate transient fault features from other interfering modes. The conventional dyadic wavelet transform decomposes the signal into wavelet subspaces with distinct central frequencies and specific frequency bandwidths. In this paper, we propose a novel theory of centralized multiresolution analysis (CMR) and reveal the implicit fractal geometry properties in CMR. A concept of nested centralized wavelet packet space (NCWPS) is introduced to describe the self-similarity phenomenon in CMR. Within the theoretical framework, the classical dyadic wavelet packet is assimilated as a subordinated proper-subset of the augmented NCWPS. Moreover, the generalized CMR characterized by tunable and flexible frequency-scale topology configuration is established using harmonic wavelet transform. The CMR can be regarded as an improved transient signature dictionary. Therefore, the CMR is combined with an improved stationary signature dictionary to ensure enhanced performance in fault feature extraction in multiple modes coupled vibration measurements. The effectiveness of the proposed method is validated using numerical simulations, a rub-impact experiment, and a case study of vibration signal analysis in steel making industry.

Summary Dural arteriovenous fistulas (DAVFs) are rare vascular abnormalities that comprise 10–15% of all intracranial arteriovenous malformations. Strong evidence suggests that the development of DAVFs in adults is acquired and may be caused by various factors, including sinus thrombosis, venous hypertension, trauma, and infection. We report a case of a 39-year-old woman with a left temporal hemorrhagic lesion and an associated developmental venous anomaly. The patient underwent craniotomy and surgery for the removal of the mass. Approximately 2 months postsurgery, the patient complained of left-sided tinnitus with a bruit over the left temporal region. Cerebral angiography showed a DAVF close to the operation site.

Summary Purpose Performing an anterior cervical discectomy by an interbody fusion is one of the surgical procedures for the treatment of cervical degenerative disc disease. Although high fusion rates have been reported with autogenous bone grafts, the immediate and long-term morbidity associated with an iliac crest harvest is well recognized. The objective of this study was to assess the efficacy of polyetheretherketone (PEEK) cages filled with a synthetic crystallic semihydrate form of calcium sulfate for an anterior cervical discectomy and fusion (ACDF). Methods Twenty-four patients treated with an ACDF using PEEK cages with Stimulan at 27 various levels of the cervical spine, some patients at more than one level, were prospectively evaluated with a minimum of 12-month follow-up (mean: 18.4 months). The cervical lordosis and fusion status were assessed with radiographs including cervical spine plain films and a computed tomography scan. New bone formation was divided into three categories, namely, Grade I, II, and III. The clinical outcomes were evaluated with the visual analog scale (VAS) score for neck and arm pain at 6 and 12 months. Results At approximately 12 months during the course of follow-up, the radiographs demonstrated Grade I, II, and III new bone formation at levels 2, 7, and 18, respectively. None of the patients experienced implant-related complications, such as cage failure or migration. Clinical outcomes evaluated with the VAS score demonstrated a significant improvement in both neck and arm pain. No complications associated with the use of PEEK cages were observed. Conclusion The anterior cervical fusion using the PEEK cage with calcium sulfate demonstrated positive radiologic and clinical outcomes. Therefore, the use of the PEEK cage packed with Stimulan is a safe and effective alternative to autologous iliac bone grafts.

p t d a T t Pigmented villonodular synovitis (PVNS) is an infrequently occurring proliferative lesion arising from the synovial membranes of particular body joints, bursae, and associated tendon sheaths. This condition was first described by Jaffe et al in 1941 and has an annual incidence of 1.8 cases per 1 million individuals in the United States. PVNS is related to a family of lesions ncluding pigmented villonodular tenosynovitis and igmented villonodular bursitis, with the diagnosis epending on the anatomic area involved. Both nodlar and diffuse forms of PVNS are currently recogized. The most common nodular patterns associted with PVNS include giant cell tumor, xanthoma, anthogranuloma, and myeloplaxoma, with each orm generally tending to affect a discrete part of the ynovium. Diffuse PVNS, which typically affects the entire synovium, has been referred to as giant cell fibrohemangioma, chronic hemorrhagic villous synovitis, and benign polymorphocellular tumor. Alhough PVNS can occur in virtually any joint of the uman body, approximately 80% of cases involve the nee, with the hip, ankle, foot, hand, elbow, and houlder accounting for almost all other cases. To our nowledge, PVNS involvement of the temporomanibular joint (TMJ) is very uncommon, with only 45 ases reported in the literature since 1973 (Table 1).

Summary Even minor surgery can cause unexpected complications and symptoms. We report an unusual case of nerve root herniation after microsurgical discectomy. A patient who presented with low-back pain and right sciatica underwent microsurgical discectomy. Two days after the operation and after initial improvement, he suddenly experienced severe low-back pain and right sciatica again. Additionally, persistent muscle cramps and fasciculations in the right lower limb were noted. Magnetic resonance imaging revealed not only the recurrent ruptured disc fragment, but also a cerebrospinal fluid-like intensity accumulating within the epidural space and paraspinal muscle. At surgery, it was observed that nerve roots of the cauda equina were squeezed into the cavity of the intervertebral space. Surgical reposition of nerve roots and dural repair were performed, and the patient eventually recovered. Dural tears should be repaired at the time of the original operation even when the arachnoid appears intact. Dural substitution using polyglycolic acid mesh and fibrin glue is an alternative method for dural repair. An increase in abdominal pressure may play a role in cerebrospinal fluid leakage and extrusion of the cauda equina. The presence of muscle cramps and fasciculations after microsurgical discectomy or any intraspinal procedure may indicate a nerve pinch and entrapment. Nerve root incarceration should be considered in the differential diagnosis.

Background: Park-bench position is a commonly used position in patients operated with cerebellopontine tumor, microvascular decompression, or lesions of cerebellar hemisphere and vertebral artery. Several complications associated with this positioning have been described. However, the delayed airway complication resulting from park-bench position has been rarely reported in the literatures. Herein, we report a rare case of delayed airway obstruction after a posterior-fossa craniotomy with park-bench position for acoustic neuroma. Case Presentation: A 43-year-old woman, who has a right acoustic neuroma, was placed in the park-bench position for a posterior-fossa craniotomy. The anesthesia and operation were performed smoothly. However, progressive swelling in the left neck with extending to left face occurred two hours after endo-tracheal extubation. Computed tomographic scan of neck revealed diffuse swelling of the muscles and deep soft tissue in the left side. No obvious embolization of vascular system including jugular vein was found in the sonography. Because of obstruction in upper airway, orotracheal intubation and a head-up position were performed. The clinical symptoms improved gradually since the third post-operative day. She was discharged with obvious complications on the 23rd day after the operation. Conclusion: The possible mechanisms may originate from the kinking of the jugular vein due to hyper-flexed neck position during surgery. To prevent such complication, we must take great care of the anesthetized patients when placed in the forced neck position and always keep this rare but so critical complication in mind.

Reducing patients' anxiety and uncertainty are important issues in the practice of medicine. We developed a new method to educate patients in order to relieve patients' anxiety and uncertainty about upcoming surgeries. Our method consisting of integrating mobile devices, education platforms and three measurements (the State-Trait Anxiety Inventory (STAI), the Mishel Uncertainty in Illness Scale (MUIS), and a measure of satisfaction) were recorded pre and post-surgery.Both experimental and control groups showed a significant decrease in STAI and MUIS scores after surgery, but the experimental group exhibited a greater decrease in anxiety and uncertainty.Here we demonstrated that patients receiving newer education platform were more satisfied than those receiving conventional education or the currently available conventional education model. BackgroundEducating patients about receiving surgical procedures is becoming an important issue, as it can reduce anxiety and uncertainty while helping to hasten decisions for undergoing time sensitive surgeries. We evaluated a new integrated education model for patients undergoing cervical disc herniation surgery using a quasi-experimental design. MethodsThe participants were grouped into either the new integrated educational model (nź=ź32) or the standard group (nź=ź32) on the basis of their ward numbers assigned at admission. Anxiety, uncertainty, and patient satisfaction were measured before (pre-test) and after the educational intervention (post-test-1) and post-surgery (post-test-2) to assess the effectiveness of the model in this intervention. ResultsWe found that the generalized estimating equation modeling demonstrated this new integrated education model was more effective than the conventional model in reducing patients' anxiety and uncertainty (pź

We report a case of intrathecal baclofen infusion pump implantation complicated by migration of the catheter tip. A 55-year-old man required an intrathecal baclofen infusion for severe spasticity 4 years after a cervical spinal cord injury with incomplete tetraparesis. Twelve months after initial implantation of the device, the patient began to experience a recurrence of trunk tightness and spasticity. Subsequent X-ray and computed tomography evaluations of the catheter system revealed pooling of contrast medium outside of the intrathecal distribution in the lumbar subcutaneous region of the back and therefore migration of the pump catheter tip. At surgical revision, emphasis was placed on minimizing the length of catheter outside of the spine and securing the catheter in the supraspinous fascia with a right-angled anchor. The distance between the anchors and the entry point of the catheter into the supraspinous fascia was also reduced to prevent slipping when the patient bends forward. After surgery, the patients spasticity improved and, 1 year later, he has experienced no further complications during follow-up, requiring an average baclofen dose of 150 microg/day. Here, we describe several surgical methods intended to secure the intrathecal catheter and prevent catheter migration. Other complications related to catheter failure are also highlighted.

Stem cells have great potential for clinical application because of their self-renewal property and ability to differentiate into many types of cells, but because there are ethical and biological limitations with current sources of stem cells, the search continues for more suitable sources of multipotent cells. We have reported previously on a population of multipotent cells isolated from the human term placenta, an ethically unproblematic and easily available source of tissue. These placenta-derived multipotent cells (PDMCs) can differentiate into lineages of mesenchymal tissues, including osteoblasts and adipocytes, as well as non-mesenchymal tissue of neuron-like cells. We further examined the ability of PDMCs to differentiate into all 3 types of neural cells--neurons, astrocytes, and oligodendrocytes--under various induction conditions, including retinoic acid (RA), 1-methyl-3-isobutylxanthine (IBMX), and co-culture with neonatal rat brain cells. PDMCs exhibited outgrowth of processes and the expression of neuron-specific molecules such as neuron-specific enolase upon induction. Co-culture with neonatal rat brain cells also induced neural differentiation. Our results indicate that PDMCs can be differentiated into neural cell types of the human nervous system upon exposure to RA, IBMX, or primary rat brain cells.

This study attempted to enhance the efficacy of peripheral nerve regeneration using our previously developed gelatin-tricalcium phosphate (GTG) conduits by incorporating them with nerve growth factors and cultured Schwann cells. The nerve growth factors were covalently immobilized onto the GTG conduits (GEN) using carbodiimide. Schwann cells were harvested from neonatal Lewis rats, cultured for seven days and injected into the GEN conduits. The experiment was performed in three groups: GTG conduits, GEN conduits and GEN conduits with Schwann cells injected (GEN+Sc). The effects of different conduits (GTG, GEN and GEN with Schwann cells) on the peripheral nerve regeneration were evaluated in rat sciatic nerve repair model. 24 weeks after implantation of conduits, degradation of the conduits in all groups was illustrated by the fragmentation of the conduits. All conduits were well tolerated by the host tissue. Under microscopic evaluations, regenerated nerve tissue with myelinated and unmyelinated axons presented in all groups. Histomorphometrically, the total nerve area of GEN+Sc group was significantly higher than GTG group. Conversely, the autotomy score evaluated 12 weeks after nerve repair showed better results for GTG group. Besides, GEN+Sc group had the highest average recovery index of compound muscle action potential, but the difference among each group did not reach statistical significance. Although the electrophysiological recovery of nerve was not significantly improved with GEN+Sc conduit, nerve repair using tissue engineered conduits still provided better histological results. However, it should be noticed that autotomy may be the price paid for enhanced peripheral nerve.

Objectives: A two-stage operation is essential for patients with cervical spine myelopathy that is the result of concomitant ligamentum flavum and posterior longitudinal ligament ossification. Methods: Modified open door laminoplasty with a miniplate and screw from the posterior approach was carried out first. Then anterior decompression and fusion with a Casper plate and Surgibone at the C5-6 intervertebral space were carried out 1 week after the first operation. Results: One week after the second procedure, the postoperative Nurick score improved from four to two. The patient withstood the whole procedure well and within one week was noted to have improved muscle strength. Conclusions: The two-stage operation is a safe and effective choice for treating concomitant OPLL and OLF in the cervical spine with radiculomyelopathy.

Severe Acute Respiratory Syndrome (SARS) has become the major of health issues since its outbreak early 2003. No analyses by bibliometric technique that have examined this topic exist in the literature. The objective of this study is to conduct a bibliometric analysis of all SARS-related publications in Science Citation Index (SCI) in the early stage. A systematic search was performed using the SCI for publications since SARS outbreak early 2003. Selected documents included 'severe acute respiratory syndrome' or 'SARS' as a part of its title, abstract, or keyword from the beginning stage of SARS outbreak, March till July 8, 2003. Analysis parameters included authorship, patterns of international collaboration, journals, language, document type, research institutional address, times cited, and reprint address. Citation analysis was mainly based on impact factor as defined by Journal Citation Reports(JCR) issued in 2002 and on the actual citation impact (ACI), which has been used to assess the impact relative to the whole field and has been defined as the ratio between individual citation per publication value and the total citation per publication value. Thirty-two percent of total share was published as news features, 25% as editorial materials, 22% as articles, 13% as letters, and the remaining being biographic items, corrections, meeting abstracts, and reprints. The US dominated the production by 30% of the total share followed closely by Hong Kong with 24%. Sixty-three percent of publication was published by the mainstream countries. The SARS publication pattern in the past few months suggests immediate citation, low collaboration rate, and English and mainstream country domination in production. We observed no associations of research indexes with the number of cases.

Spinal epidural lipomatosis (SEL), an abnormal localized or tumor-like accumulation of fat in the epidural space, is an infrequent complication of chronic steroid usage and an uncommon cause of spinal cord compression. During the period of 1990 to 2006, we have two cases of medically heath SEL patients without history of steroid administration. Their initial clinical manifestations were low back pain, progressive lower extremities weakness, numbness, followed by rapid deterioration of neurogenic intermittent claudication. They were misdiagnosed and treated as degenerative spinal disease for a long time. Due to prominent neurological deficit, lumbar magnetic resonance image (MRI) was obtained and showed SEL. These 2 patients all underwent laminectomy and removal of epidural fat. Postoperatively, they both showed improvement. We reviewed the literature and discussed the current concept in the management of SEL.

Hemangioblastomas, highly vascular tumors, occur sporadically or associated with von Hippel–Lindau (VHL) disease. Diverse mutations in the VHL gene inactivate the VHL protein and constitute the molecular etiology of the disease. Changes in VHL gene were analyzed in patients with multiplex ligation-dependent probe amplification and single-strand conformation polymorphism analyses. We report here that other angiogenesis-related changes in vitronectin were identified with 2D electrophoresis of plasma samples and restriction fragment length polymorphisms. Our findings revealed that most patients (80.0%) with a familial VHL deletion carried the threonine (T) allele at vitronectin codon 381. Adults simultaneously carrying a VHL defect and the T allele were 5.0-fold more likely to be affected by VHL disease than were methionine/methionine (M/M) homozygotes carrying a VHL defect. Patients with sporadic hemangioblastoma, C-terminally truncated VHL protein or a large deletion in the VHL gene, and the T allele were 18.0-fold more likely to develop recurrent disease. Taken together, individuals with mutated VHL are more likely to be affected by familial or recurrent sporadic hemangioblastoma when carrying the M/T or T/T genotype at codon 381 of vitronectin.

In order to modulate the mechanical properties of gelatin, we previously developed a biodegradable composite composed by tricalcium phosphate and glutaraldehyde crosslinking gelatin (GTG) feasible for surgical manipulation. In this study, we evaluated the in vivo applications of GTG conduit for peripheral nerve repair. The effect of sciatic nerve reconstruction was compared between resorbable permeable GTG conduits and durable impermeable silicone tubes. Traditional methods of assessing nerve recovery following peripheral nerve repair including histomorphometric and electrophysiologic features were conducted in our study. In addition, autotomy score and sciatic function index (SFI) in walking tract analysis were used as additional parameters for assessing the return of nerve function. Twenty-four weeks after sciatic nerve repair, the GTG conduits were harvested. Microscopically, regeneration of nerves was observed in the cross-section at the mid portion of all implanted GTG conduits. The cross-sectional area of regenerated nerve of the GTG group was significant larger than that of the silicone group. In the compound muscle action potentials (CMAP), the mean recovery index of CMAP amplitude was 0.24 ± 0.02 for the silicone group, 0.41 ± 0.07 for the GTG group. The mean SFI increased with time in the GTG group during the evaluation period until 24 weeks. Walking tract analysis showed a higher SFI score in the GTG group at both 12 and 24 weeks. The difference reached a significant level at 24 weeks. Thus, the histomorphometric, electrophysiologic, and functional assessments demonstrate that GTG can be a candidate for peripheral nerve repair. © 2005 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2006

Object. The management regimen for depressed skull fractures in infants can be conservative or surgical. The aim of this study was to provide a rational principle of management for simple depressed skull fractures in infants. Methods. A protocol of nonsurgical treatment for a simple depressed skull fracture was designed for all affected infants during the period from 1985 to 2001. Conservative management was used for those with a depressed fracture measuring less than 5 mm in depth, whereas vacuum extraction was applied for larger and deeper depressions. All of the patients were evaluated for initial results and later outcomes. Twenty-five infants suffering simple depressed skull fractures were consecutively enrolled. According to our protocol, 11 patients received conservative management by close observation only. Spontaneous restoration of the depression was observed in eight patients within a period of 1 to 6 months. For the remaining 14 patients, vacuum extraction was performed. A negative pressure of 0.3 to 0.8 kg/cm 2 (mean 0.49 kg/cm 2 ) was applied for a duration of 20 to 90 seconds (mean 43.6 seconds). All but one patient experienced complete recovery following extraction. The depressions of the four patients that were residual after initial management smoothed out with time. No neurological deficit or later epilepsy was noted in any patient. Conclusions. Nonsurgical management can be the treatment of choice for infants with simple depressed skull fractures, whereas vacuum extraction is one option for larger and deeper depressions to obtain prompt resolution and relieve major family anxiety, without taking additional risks.

Intramedullary hemangioblastomas are relatively rare intraspinal tumors. Total removal of these tumors without causing significant neurological deficit remains a great challenge. This study analyzed the preoperative characteristics, management, and outcome in patients with successful total removal of spinal intramedullary hemangioblastomas.Data from the medical records of patients with intraspinal hemangioblastomas treated from 1993 to 2003 were reviewed. The neurological function of these patients was graded and the preoperative data were recorded and correlated with clinical outcome.Ten patients with spinal intramedullary hemangioblastomas underwent microsurgical resection by the same neurosurgeon during the 10-year study period. They included 3 men and 7 women with age ranging from 20 to 49 years, with a mean age of 33 years. Five of the patients met the diagnostic criteria for von Hippel-Lindau disease. Preoperative neurological function was grade I in 6 patients, grade II in 3 patients and grade III in 1 patient. Immediate postoperative neurological function was worse in 3 cases, but all of these patients recovered their preoperative function within 3 weeks. At 3 months' follow-up, 9 patients had achieved functional grade I, and 1 patient with preoperative grade III function had improved to grade II.Detailed preoperative evaluation and skillful microsurgery are mandatory in successful total removal of intramedullary hemangioblastomas. The management of spinal hemangioblastomas associated with von Hippel-Lindau disease requires a cautious observation of clinical course and timely surgical intervention of symptomatic lesions to avoid possible neurological deficit.

Summary A review of the literature reveals only a few cases of spinal subdural empyema. Etiologies of spinal subdural empyema include hematogenous spread from skin lesions, systemic sepsis, direct spread from spinal osteomyelitis and complications of discography. However, in this report, we describe a patient who developed spinal subdural empyema following several cervical acupuncture sessions. Operative treatment with adequate laminectomy, removal of abscess, and copious irrigation resulted in good recovery. Microbiologic culture study of pus obtained at surgery was positive for Staphylococcus aureus. The need for sterilization procedures for acupuncture is emphasized and a brief review of the relevant literature is presented.

We reported a case of a huge osteoblastoma in the skull base of a young girl who had developed blindness in her right eye 1 year prior to examination. CT showed a large expansile bony lesion with eggshell margin over the skull base. MR imaging showed mixed solid and cystic parts with multiple fluid–fluid levels in the lesion. The optic chiasma and bilateral optic nerves were severely compressed by the tumor.

OBJECTIVE AND IMPORTANCE: Intraosseous schwannomas (neurilemomas) are rare neoplasms. In one large series, schwannomas accounted for less than 0.2% of all primary bone tumors. These schwannomas most commonly arise in the mandible and have also been observed, very rarely, in the vertebra. We present a patient with an unusual intraosseous schwannoma in the lumbar vertebra. CLINICAL PRESENTATION: A 58-year-old man who was admitted to Cathay General Hospital had complained of numbness and pain in his lower extremities for approximately 1 year. At the time of admission, a neurological examination revealed mild motor weakness and sensory numbness bilaterally in his lower legs. Magnetic resonance images showed a neoplastic lesion occupying the entire L4 body and the superior part of the L5 body, with marked perivertebral protrusion and compression of the thecal sac and bilateral neuroforamina. INTERVENTION: The patient underwent a computed tomography-guided needle biopsy and a two-stage operation. During the initial surgical procedure, the tumor mass was totally removed via an anterolateral approach. Fixation and fusion of the third to fifth lumbar vertebral bodies was accomplished using a full-thickness iliac bone graft with an anterior locking plate and screws. During the second operation, posterior fusion of L2, L3, L4, L5, and S1 with Luque wires and a Hartshill rectangle rod was performed to increase the spinal stability. CONCLUSION: Intraosseous schwannomas are rare neoplasms that are not commonly observed in the lumbar vertebral bodies. Schwannomas in the lumbar spine commonly originate from the nerve passing through the neural foramina. We report a rare case of L4 intraosseous schwannoma, the magnetic resonance imaging, computed tomographic, and histological findings, and the surgical procedures.

Inrracranial arachnoid cysts are believed to be congenital; they can become symptomatic in pediarric patients. Chronic subdural hematomas tend to occur in elderly patients with a history of mild head injury a few months prior to the onset of symptoms. However, these two distinct clinical entities sporadically occur together in relatively young patients. We report a 29-year-old man who presented with headache and dizziness of 2 months' duration. Brain computed tomography revealed a huge chronic subdural hematoma over the left frontoparietal lobe, with an incidental finding of an arachnoid cyst over the left sylvian fissure. In light of a literature review, we discuss arachnoid cysts as a possible risk factor for subdural hematoma, especially in young adults.

We present the case of a 1-year-old girl with persistent vomiting who was found to have a disproportionately large immature teratoma in the third ventricle. Magnetic resonance imaging demonstrated a heterogeneous intracranial mass in the third ventricle, with a compressed left cerebral hemisphere and hydrocephalus. Bifrontal craniotomy via a transchiasmatic approach achieved total resection of the tumor. No significant neurologic deficit was seen except for double vision and disturbances in eye movement. Third ventricle immature teratoma, although extremely rare, may present as a suprasellar mass lesion and hydrocephalus. The prognosis after gross total resection is favorable; however, radiotherapy is usually postponed until 36 to 48 months of age in order to avoid complications such as stunted growth, endocrine disturbances and neuropsychologic problems.