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Neurosurgery
Kinds of Neurosurgery Selected AbstractsPERSONAL IDENTITY, ENHANCEMENT AND NEUROSURGERY: A QUALITATIVE STUDY IN APPLIED NEUROETHICSBIOETHICS, Issue 6 2009NIR LIPSMAN ABSTRACT Recent developments in the field of neurosurgery, specifically those dealing with the modification of mood and affect as part of psychiatric disease, have led some researchers to discuss the ethical implications of surgery to alter personality and personal identity. As knowledge and technology advance, discussions of surgery to alter undesirable traits, or possibly the enhancement of normal traits, will play an increasingly larger role in the ethical literature. So far, identity and enhancement have yet to be explored in a neurosurgical context, despite the fact that 1) neurological disease and treatment both potentially alter identity, and 2) that neurosurgeons will likely be the purveyors of future enhancement implantable technology. Here, we use interviews with neurosurgical patients to shed light on the ethical issues and challenges that surround identity and enhancement in neurosurgery. The results provide insight into how patients approach their identity prior to potentially identity-altering procedures and what future ethical challenges lay ahead for clinicians and researchers in the field of neurotherapeutics. [source] Cortical Dysplasias and Epilepsy: Multi-Institutional Survey in JapanEPILEPSIA, Issue 2000Morimi Shimada Purpose: Cortical dysplasia (CD) is a major brain malformation causing intractable epilcpsy. Neurosurgery now succcssfully controls some intractable epilepsies associated with CD. In this study, thc incidence 11 epilepsy and thc frequency of seizurcs were analyzed in different types 01 CD. Methods: This study, supported by a rcse;lrch grant from the Ministry of Health and Wellare of Japan, is part of a research project on the clinical presentation and pathogcnesis of brain dysgenesis. Questionnaires regarding the type of CD, family and pact historics, clinical signs and symptoms and their severity were distributed to I200 institutions comprising child neurologists or pediatricians. CDs werc classified into following 6 types; lissencephaly (agyria-pachygyria spcctrum), cobblestone lissencephaly, polymicrogyria including schizencephaly and hilateral perisylvian syndrome, diffuse heterotopia, focal heterotopia, and hemiinegalencephaly. All patients who had been diagnoscd as CD either by MRI, CT, autopsy or histological cxamination at or after surgical treatment wcre included. Diagnosis of CD by CT or MRI was mainly made by a radiologist, child neurologist, or pediatrician. Double classification was corrected. Epilepsy was classified according to criteria of the ILEA. Seizure frcquencies wcre recorded. Results: A total or 676 cases from 328 institutions was availablc, and distributed as follows: 277 of lissencephaly, I48 of cobblestone lissencephaly (10 cases of Walkcr-Warburg syndrome and 138 Fukuyaina type congcnital muscular dystrophy), I30 of polymicrogyria, 40 of diffuse heterotopia (24 subcortical band hetcrotopia and I6 perivcntricular nodular hcterotopia), 37 of focal heterotopia, and 44 of hemimegalencephaly. In 130 cases of polymicrogyria, 13 cases of bilatcral perisylvian syndrome, and 38 cases of schizencephaly were includcd. Of 667 cases available for study, 500 (75.0%) had epilepsy in which generalized epilepsy including West and Lcnnox syndromes comprised 54.1 % and localization-related epilepsies comprised 46.7%. Thc frequency of seizures could be ascertained in 455 cases, of which 36.0% had daily seizures, and I I .4%) had more than onc seizure per week. The incidencc of epilepsy in cach type of CD was as follows: 86% inlissencephaly, 50% in cobblestone lissencephaly (patients with WalkcrWarburg syndrome had epilepsy in 90%, whercas those with Fukuyama type congenital muscular dystrophy had epilepsy in 46.7%), 71.3% in polymicrogyria, 77.5% in diffusc hetcrotopia (9 1.7% in subcortical band heterotopia and 56.2% in periventricular nodular heterotopia), 74.3% in focal heterotopia, and 93.2% in hemimegalcncephaly. Conclusion: As recent investigations have reported, this study confirmed the high incidence of intractable cpilepsy in CDs. Epilepsy was more prevalcnt in cases with subcortical heterotopia than i n cascs with periventricular nodular helcrotopia. Thc incidcnce or epilepsy was also higher in the focal hcterotopias located subcortically than those dccper in white matter or in the periventricular region. Thcse differences in incidence of epilepsy depending on the location of hcterotopia may give somc clues to the nature of epileptogenesis in CD. [source] Use of the internet and of the NHS direct telephone helpline for medical information by a cognitive function clinic populationINTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 2 2003A. J. Larner Abstract Background Internet websites and medical telephone helplines are relatively new and huge resources of medical information (,cybermedicine' and ,telemedicine', respectively) accessible to the general public without prior recourse to a doctor. Study Objectives To measure use of internet websites and of the NHS Direct telephone helpline as sources of medical information by patients and their families and/or carers attending a cognitive function clinic. Design and Setting Consecutive patients seen by one consultant neurologist over a six-month period in the Cognitive Function Clinic at the Walton Centre for Neurology and Neurosurgery, a regional neuroscience centre in Liverpool, UK. Results More than 50% of patients and families/carers had internet access; 27% had accessed relevant information, but none volunteered this. 82% expressed interest in, or willingness to access, websites with relevant medical information if these were suggested by the clinic doctor. Although 61% had heard of the NHS Direct telephone helpline, only 10% of all patients had used this service and few calls related to the reason for attendance at the Cognitive Function Clinic. Conclusions Internet access and use is common in a cognitive function clinic population. Since information from internet websites may shape health beliefs and expectations of patients and families/carers, appropriately or inappropriately, it may be important for the clinic doctor to inquire about these searches. Since most would use websites suggested by the doctor, a readiness to provide addresses for appropriate sites may prove helpful. Copyright © 2003 John Wiley & Sons, Ltd. [source] Evaluating Patients with Acute Ischemic Stroke with Special Reference to Newly Developed Atrial Fibrillation in Cerebral EmbolismPACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 9 2007MINORU TAGAWA M.D. Background:Cardioembolic strokes are extensive and have a poor prognosis. To identify the cardiovascular risk factors of cardioembolic stroke, we evaluated the cardiovascular status with special reference to persistent atrial fibrillation (AF) and paroxysmal atrial fibrillation (PAF) combined with the type of acute ischemic stroke. Methods:We divided 315 consecutive patients admitted to our Department of Neurosurgery with an acute ischemic stroke into four types of brain infarction using clinical history, onset pattern of stroke, and brain imaging: cardioembolic (group E, n = 105), lacunar (group L, n = 92), atherothrombotic (group T, n = 111), and unclassified (n = 7). All patients underwent standard electrocardiography (ECG), a 24-hour ECG recording (Holter ECG) and transthoracic echocardiography (UCG). Results:Persistent AF or PAF was detected in 97 patients (31.5%) using Holter ECG: more frequently in group E (67.6%) than in groups L (15.2%) or T (9.2%). Persistent AF or PAF was first diagnosed on admission using a standard ECG in 16 patients (5.2%) with no previous history and 14 of these patients belonged to group E (13.3%). PAF was newly detected on Holter ECG in another 26 patients (8.4%) and 13 of these patients (12.4%) belonged to group E. Concerning UCG, left atrial enlargement and mitral regurgitation were more frequent in group E than in group L or T. Conclusion:Holter ECG in addition to ECG on admission is important for detecting persistent AF or PAF in patients with ischemic stroke, especially with cardioembolism as diagnosed by neuroimaging. [source] Robotics in neurosurgery: state of the art and future technological challengesTHE INTERNATIONAL JOURNAL OF MEDICAL ROBOTICS AND COMPUTER ASSISTED SURGERY, Issue 1 2004L Zamorano Abstract The use of robotic technologies to assist surgeons was conceptually described almost thirty years ago but has only recently become feasible. In Neurosurgery, medical robots have been applied to neurosurgery for over 19 years. Nevertheless this field remains unknown to most neurosurgeons. The intrinsic characteristics of robots, such as high precision, repeatability and endurance make them ideal surgeon's assistants. Unfortunately, limitations in the current available systems make its use limited to very few centers in the world. During the last decade, important efforts have been made between academic and industry partnerships to develop robots suitable for use in the operating room environment. Although some applications have been successful in areas of laparoscopic surgery and orthopaedics, Neurosurgery has presented a major challenge due to the eloquence of the surrounding anatomy. This review focuses on the application of medical robotics in neurosurgery. The paper begins with an overview of the development of the medical robotics, followed by the current clinical applications in neurosurgery and an analysis of current limitations. We discuss robotic applications based in our own experience in the field. Next, we discuss the technological challenges and research areas to overcome those limitations, including some of our current research approaches for future progress in the field Copyright © 2004 Robotic Publications Ltd. [source] Principles and Practice of Pediatric Neurosurgery.ANZ JOURNAL OF SURGERY, Issue 1-2 2010Second Edition No abstract is available for this article. [source] Neurosurgical Operative Atlas: Paediatric Neurosurgery (Second Edition)ANZ JOURNAL OF SURGERY, Issue 12 2009Brian Owler MB BS BSc(Med)(Hons) PhD FRACS. No abstract is available for this article. [source] In vivo muscle architecture and size of the rectus femoris and vastus lateralis in children and adolescents with cerebral palsyDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 10 2009NOELLE G MOREAU PHD PT Aim, Our aim was to investigate muscle architecture and size of the rectus femoris (RF) and vastus lateralis (VL) in children and adolescents with cerebral palsy (CP) compared with age-matched typically developing participants. Method, Muscle architecture and size were measured with ultrasound imaging in 18 participants with spastic CP (9 females, 9 males; age range 7.5,19y; mean age 12y [SD 3y 2mo]) within Gross Motor Function Classification System levels I (n=4), II (n=2), III (n=9), and IV (n=3) and 12 typically developing participants (10 females, 2 males; age range 7,20y; mean age 12y 4mo [SD 3y 11mo]). Exclusion criteria were orthopedic surgery or neurosurgery within 6 months before testing or botulinum toxin injections to the quadriceps within 3 months before testing. Results, RF cross-sectional area was significantly lower (48%), RF and VL muscle thickness 30% lower, RF fascicle length 27% lower, and VL fascicle angle 3° less in participants with CP compared to the typically developing participants (p<0.05). Intraclass correlation coefficients were ,0.93 (CP) and , 0.88 (typical development), indicating excellent reliability. Interpretation, These results provide the first evidence of altered muscle architecture and size of the RF and VL in CP, similar to patterns observed with disuse and aging. These alterations may play a significant role in the decreased capacity for force generation as well as decreased shortening velocity and range of motion over which the quadriceps can act. [source] Association of ABCB1 genetic variants 3435C>T and 2677G>T to ABCB1 mRNA and protein expression in brain tissue from refractory epilepsy patientsEPILEPSIA, Issue 9 2008Igor Mosyagin Summary Purpose: There is evidence from studies in rodents that P-glycoprotein (P-gp) overexpression is implicated in the causation of refractory epilepsy. Genetic variants in the human ABCB1 (MDR1) gene were shown to affect the expression levels of the transporter in various tissues and to be associated with refractory epilepsy. However, the effect of the genetic variants on the P-gp level in epileptogenic brain tissue is poorly investigated. In the present study, we examined the impact of putatively functional polymorphisms 3435C>T and 2677G>T in the ABCB1 gene on the ABCB1 mRNA expression and P-gp content in human brain tissue from epileptogenic foci of the patients with refractory epilepsy. Methods: Fresh brain tissue specimens were obtained from therapy-refractory epilepsy patients during neurosurgery of the epileptogenic focus. We determined the ABCB1 mRNA expression in 23 samples using 5, exonuclease-based real-time polymerase chain reaction (PCR) as well as the P-gp content in 32 samples determined by immunohistochemistry, genotyping was performed by PCR/restriction fragment length polymorphism (RFLP). Results: There was lack of association of 3435C>T and 2677G>T as well as diplotype configurations on ABCB1 mRNA expression and P-gp content in epileptogenic brain tissues. Conclusions: We cannot exclude an association of ABCB1 variants on P-gp function, but our results suggest that brain ABCB1 mRNA and protein expression is not substantially influenced by major ABCB1 genetic variants thus explaining in part results from case-control studies obtaining lack of association of ABCB1 polymorphisms to the risk of refractory epilepsy. [source] Heat Shock Protein-27 Is Upregulated in the Temporal Cortex of Patients with EpilepsyEPILEPSIA, Issue 12 2004Hans-J Bidmon Summary:,Purpose: Heat shock protein-27 (HSP-27) belongs to the group of small heat shock proteins that become induced in response to various pathologic conditions. HSP-27 has been shown to protect cells and subcellular structures, particularly mitochondria, and serves as a carrier for estradiol. It is a reliable marker for tissues affected by oxidative stress. Oxidative stress and related cellular defence mechanisms are currently thought to play a major role during experimentally induced epileptic neuropathology. We addressed the question whether HSP-27 becomes induced in the neocortex resected from patients with pharmacoresistant epilepsy. Methods: Human epileptic temporal neocortex was obtained during neurosurgery, and control tissue was obtained at autopsy from subjects without known neurologic diseases. The tissues were either frozen for Western blot analysis or fixed in Zamboni's fixative for the topographic detection of HSP-27 at the cellular level by means of immunohistochemistry. Results: HSP-27 was highly expressed in all epilepsy specimens and in the cortex of a patient who died in the final stage of multiple sclerosis (positive control), whereas only low amounts of HSP-27 were detectable in control brains. In epilepsy patients, HSP-27 was present in astrocytes and in the walls of blood vessels. The intracortical distribution patterns varied strongly among the epilepsy specimens. Conclusions: These results demonstrate that HSP-27 becomes induced in response to epileptic pathology. Although the functional aspects of HSP-27 induction during human epilepsy have yet to be elucidated, it can be concluded that HSP-27 is a marker for cortical regions in which a stress response has been caused by seizures. [source] Assessment of idiopathic normal pressure patients in neurological practice: the role of lumbar infusion testing for referral of patients to neurosurgeryEUROPEAN JOURNAL OF NEUROLOGY, Issue 6 2008A. Brean Background and purpose:, In neurological practice patients with tentative idiopathic normal pressure hydrocephalus (iNPH) usually are referred to neurosurgery based on clinical and radiological findings. Hydrodynamic assessment using lumbar infusion testing might be helpful in selecting patients. To retrospectively analyse lumbar infusion tests done in neurological practice in iNPH patients to see how infusion test results relate to the clinical course and shunt response. Materials and methods:, Sixty-three consecutive patients with Possible/Probable iNPH were tested during a 1-year period. The pre-operative lumbar infusion tests were assessed according to two strategies: (i) Determining the resistance to cerebrospinal fluid (CSF) outflow (Rout). (ii) Quantification of the CSF pressure (CSFP) pulsatility during lumbar infusion (Qpulse). The results were related to the prospectively followed clinical course and shunt response after 12 months. Results:, The lumbar infusion-derived parameters Rout and Qpulse related weakly. Shunt response after 12 months was not related to Rout, but was highly related to the Qpulse. False negative results of lumbar infusion testing were observed in 16% of the patients. Discussion:, In neurological practice lumbar infusion testing may be useful for determining which patients to refer to neurosurgery. Our data favour determination of CSFP pulsatility (Qpulse) rather than Rout for prediction of shunt response. [source] Cranioplasty in ancient Peru: a critical review of the evidence, and a unique case from the Cuzco areaINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 3 2010J. W. Verano Abstract Cranioplasty is a well-known procedure in modern neurosurgery. Although some authors have claimed it was also performed by prehistoric trepanners in various parts of the world, there is little hard evidence to support this. Here we review various claims of cranioplasty in Peru, where trepanation was widely practised in Prehispanic times. We find little support for assertions that cranioplasty was common. One recently discovered burial from the Cuzco region, however, provides the first documented case of the reinsertion of a bone plug into a trepanation opening. Copyright © 2008 John Wiley & Sons, Ltd. [source] Update of radiosurgery at the Royal Adelaide HospitalJOURNAL OF MEDICAL IMAGING AND RADIATION ONCOLOGY, Issue 2 2006DE Roos Summary This is an update of the Royal Adelaide Hospital radiosurgery experience between November 1993 and December 2004 comprising 165 patients with 168 intracranial lesions. Including re-treatment, there were 175 treatment episodes (163 radiosurgery and 12 stereotactic radiotherapy) at an average of 1.3 per month. The commonest lesions were acoustic neuroma (65), arteriovenous malformation (58), solitary brain metastasis (23) and meningioma (14). The clinical features, treatment details and outcome are described. Our results continue to be well within the range reported in the published work. Radiosurgery provides an elegant, non-invasive alternative to neurosurgery and conventional external beam radiotherapy for many benign and malignant brain tumours. [source] Masticatory problems after balloon compression for trigeminal neuralgia: a longitudinal study1JOURNAL OF ORAL REHABILITATION, Issue 2 2007S. R. D. T. DE SIQUEIRA summary, Idiopathic trigeminal neuralgia (ITN) is a chronic neuropathic pain that affects the masticatory system. The objective of this study was to identify orofacial pain and temporomandibular characteristics, including temporomandibular disorder (TMD), in a sample of 105 ITN patients treated with compression of the trigeminal ganglion. The evaluations occurred before, 7, 30 (1 month), 120 (3 months) and 210 days (7 months) after surgery. The Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), the Clinical Questionnaire (EDOF-HC) and Helkimo Indexes were used. Findings before neurosurgery were used as control for parameters. McNemar test and variance analysis for repetitive measurements were used for statistical analysis; 45·3% of the edentulous patients presented severe dental occlusion index; numbness was an important masticatory complaint in 42·6%; mastication became bilateral, but its discomfort continued during all period; headache and body pain reduced after surgery; TMD, present in 43·8% before surgery, increased but normalized after 7 months; jaw mobility compromise was still present, but daily activities improved after 7 months. We concluded that: (i) ITN relief reduced headache, body pain, depression and unspecific symptoms; and (ii) TMD before surgery and at 7 months suggests that this may be a contributory factor to patients' pain complaints. [source] Basal ganglia physiology and deep brain stimulation,MOVEMENT DISORDERS, Issue S1 2010Andres M. Lozano FRCSC Abstract Despite improvements in anatomic imaging of the basal ganglia, microelectrode recording is still an invaluable tool in locating appropriate targets for neurosurgical intervention. These recording also provide an unparalleled opportunity to study the pathophysiological aspects of diseases. This article reviews the principles of microelectrode recording in functional neurosurgery and discusses the pathologic neurophysiologic findings commonly encountered. It also highlights some of the potential mechanisms of action of both dopaminergic drugs and deep brain stimulation. In addition we review the recent work on pedunculopontine nucleus neurophysiology and trials of deep brain stimulation in that region for gait disturbances in Parkinson's disease. © 2010 Movement Disorder Society [source] Physical therapy in Parkinson's disease: Evolution and future challengesMOVEMENT DISORDERS, Issue 1 2009Samyra H.J. Keus PT Abstract Even with optimal medical management using drugs or neurosurgery, patients with Parkinson's disease (PD) are faced with progressively increasing mobility problems. For this reason, many patients require additional physical therapy. Here, we review the professional evolution and scientific validation of physical therapy in PD, and highlight several future challenges. To gain insight in ongoing, recently completed or published trials and systematic reviews, we performed a structured literature review and contacted experts in the field of physical therapy in PD. Following publication of the first controlled clinical trial in 1981, the quantity and quality of clinical trials evaluating the efficacy of physical therapy in PD has evolved rapidly. In 2004 the first guideline on physical therapy in PD was published, providing recommendations for evidence-based interventions. Current research is aiming to gather additional evidence to support specific intervention strategies such as the prevention of falls, and to evaluate the implementation of evidence into clinical practice. Although research focused on physical therapy for PD is a relatively young field, high-quality supportive evidence is emerging for specific therapeutic strategies. We provide some recommendations for future research, and discuss innovative strategies to improve the organization of allied health care in PD, making evidence-based care available to all PD patients. © 2008 Movement Disorder Society [source] Paradoxes of functional neurosurgery: Clues from basal ganglia recordingsMOVEMENT DISORDERS, Issue 1 2008Peter Brown MD Abstract Deep brain stimulation (DBS) can be remarkably effective in treating movement disorders such as Parkinson's disease, dystonia, and essential tremor. Yet these effects remain essentially unexplained, even paradoxical. Equally challenging is the fact that DBS of motor targets in the basal ganglia appears to reverse abnormalities of movement without any obvious deleterious effects on remaining aspects of movement. Here, we explore the extent to which the noisy signal hypothesis might help solve some of these apparent paradoxes. Essentially the hypothesis, first tentatively advanced by Marsden and Obeso (1994), suggests that disease leads to a pattern of basal ganglia activity that disrupts local and distant function and that surgery acts to suppress or override this noisy signal. Critical to the success this theory is that different disease phenotypes are associated with different patterns of noisy signal, and we survey the evidence to support this contention, with specific emphasis on different types of pathological synchronization. However, just as DBS may suppress or override noisy signals in the basal ganglia, it must equally antagonize any remaining physiological functioning in these key motor structures. We argue that the latter effect of DBS becomes manifest when baseline motor performance is relatively preserved, i.e., when pathological activity is limited. Under these circumstances, the deleterious effects of DBS are no longer obscured by its therapeutic actions in suppressing noisy signals. Whether true, oversimplified or simply incorrect, the noisy signal hypothesis has served to focus attention on the detailed character of basal ganglia discharge and its variation with disease and therapy. © 2007 Movement Disorder Society [source] Effects of stereotactic neurosurgery on postural instability and gait in Parkinson's diseaseMOVEMENT DISORDERS, Issue 9 2004Maaike Bakker MSc Abstract Postural instability and gait disability (PIGD) are disabling signs of Parkinson's disease. Stereotactic surgery aimed at the internal globus pallidus (GPi) or subthalamic nucleus (STN) might improve PIGD, but the precise effects remain unclear. We performed a systematic review of studies that examined the effects of GPi or STN surgery on PIGD. Most studies examined the effects of bilateral GPi stimulation, bilateral STN stimulation, and unilateral pallidotomy; we, therefore, only performed a meta-analysis on these studies. Bilateral GPi stimulation, bilateral STN stimulation, and to a lesser extent, unilateral pallidotomy significantly improved PIGD, and more so during the ON phase than during the OFF phase. © 2004 Movement Disorder Society [source] From functional neurosurgery to "interventional" neurology: Survey of publications on thalamotomy, pallidotomy, and deep brain stimulation for Parkinson's disease from 1966 to 2001MOVEMENT DISORDERS, Issue 8 2003Marwan I. Hariz MD Abstract Articles on surgery for Parkinson's disease (PD), published between 1966 and 2001, were reviewed with respect to whether the first author had a neurosurgical affiliation, and whether the papers appeared in neurosurgical or non-neurosurgical journals. Between 1966 and 1979, neurosurgeons and non-neurosurgeons published almost equally on surgery for PD in both neurosurgical and non-neurosurgical journals; between 1980 and 1995, the majority of publications were by neurosurgeons in neurosurgical journals; and after 1995, non-neurosurgeons were more often first authors of surgical publications and these were more frequent in non-neurosurgical journals. The fact that the first author of surgical publications on PD is often a non-neurosurgeon may have some bearing on the reported results of surgery. © 2003 Movement Disorder Society [source] Gentle dorsal root retraction and dissection can cause areflexia: Implications for intraoperative monitoring during "selective" partial dorsal rhizotomyMUSCLE AND NERVE, Issue 10 2001Eric L. Logigian MD Abstract During partial dorsal rhizotomy (PDR), intraoperative dorsal rootlet stimulation often evokes nonreflex, rather than reflex, motor responses that are due to costimulation of adjacent ventral roots. Intraoperative areflexia typically predicts that motor responses evoked by dorsal rootlet stimulation are nonreflexive. The cause of areflexia during PDR is in part due to anesthesia, but other mechanisms are likely to play a role as well. In this study of three consecutive patients undergoing lumbosacral neurosurgery, soleus H-reflexes evoked by tibial nerve stimulation at the popliteal fossa were found to suddenly decline in amplitude following retraction and gentle dissection of the S-1 dorsal root. In one areflexic patient, dorsal rootlet stimulation proximal to the main site of dissection evoked soleus H-reflexes, although they could not be evoked by tibial nerve stimulation. We conclude that the gentle retraction and dissection of dorsal rootlets that occurs during PDR can induce conduction block of reflex afferents. High-intensity dorsal rootlet stimulation distal to the site of conduction block may then evoke not reflex responses, but rather nonreflex motor responses, due to the costimulation of adjacent ventral roots. © 2001 John Wiley & Sons, Inc. Muscle Nerve 24: 1352,1358, 2001 [source] An audit of serious complications during neurosurgery in children using the sitting positionPEDIATRIC ANESTHESIA, Issue 6 2000C. Ralston No abstract is available for this article. [source] Potential bias caused by control selection in secondary data analysis: Nonaspirin nonsteroidal anti-inflammatory drugs and hemorrhagic stroke,PHARMACOEPIDEMIOLOGY AND DRUG SAFETY, Issue 6 2010Nam-Kyong Choi PhD Abstract Background This study investigated the potential for bias introduction when selecting controls for secondary analysis of case-control study data. Methods We used a data set previously collected for an acute brain bleeding analysis (ABBA) study, which was designed to investigate the risk of hemorrhagic stroke (HS) resulting from the use of phenylpropanolamine in Korea. Cases in that study had experienced an HS. Each HS case was matched with age- and gender-based hospital and community controls. Information was obtained on drug exposures including nonaspirin nonsteroidal anti-inflammatory drugs (NANSAIDs). Odds ratios (OR) for, and 95% confidence intervals (CI) of, experiencing an HS were calculated using conditional logistic regressions for each control group. Results A total of 940 patients were matched with 1880 controls. The OR of HS occurring in NANSAID users was 1.18 (95%CI, 0.80,1.73) in community controls and 0.67 (95%CI, 0.45,0.98) in hospital controls. The majority of the hospital controls were selected from patients who had visited neurology, neurosurgery, or orthopedic departments. Conclusion The difference between OR values estimated from hospital and community controls could be the result of selection bias. The study data were originally obtained for a different purpose than this study, and NANSAID use was not considered when the hospital controls were selected. When performing secondary analyses, extra care is needed to note whether the results are consistent across control groups and whether there are indications of bias related to the selection of those controls. Copyright © 2010 John Wiley & Sons, Ltd. [source] Applications of Free-Electron Lasers in the Biological and Material Sciences,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2005G. S. Edwards ABSTRACT Free-Electron Lasers (FELs) collectively operate from the terahertz through the ultraviolet range and via intracavity Compton backscattering into the X-ray and gamma-ray regimes. FELs are continuously tunable and can provide optical powers, pulse structures and polarizations that are not matched by conventional lasers. Representative research in the biological and biomedical sciences and condensed matter and material research are described to illustrate the breadth and impact of FEL applications. These include terahertz dynamics in materials far from equilibrium, infrared nonlinear vibrational spectroscopy to investigate dynamical processes in condensed-phase systems, infrared resonant-enhanced multiphoton ionization for gas-phase spectroscopy and spectrometry, infrared matrix-assisted laser-desorption-ionization and infrared matrix-assisted pulsed laser evaporation for analysis and processing of organic materials, human neurosurgery and ophthalmic surgery using a medical infrared FEL and ultraviolet photoemission electron microscopy for nanoscale characterization of materials and nanoscale phenomena. The ongoing development of ultraviolet and X-ray FELs are discussed in terms of future opportunities for applications research. [source] Target registration and target positioning errors in computer-assisted neurosurgery: proposal for a standardized reporting of error assessmentTHE INTERNATIONAL JOURNAL OF MEDICAL ROBOTICS AND COMPUTER ASSISTED SURGERY, Issue 4 2009Gerlig Widmann Abstract Background Assessment of errors is essential in development, testing and clinical application of computer-assisted neurosurgery. Our aim was to provide a comprehensive overview of the different methods to assess target registration error (TRE) and target positioning error (TPE) and to develop a proposal for a standardized reporting of error assessment. Methods A PubMed research on phantom, cadaver or clinical studies on TRE and TPE has been perfomed. Reporting standards have been defined according to (a) study design and evaluation methods and (b) specifications of the navigation technology. Results The proposed standardized reporting includes (a) study design (controlled, non-controlled), study type (non-anthropomorphic phantom, anthropomorphic phantom, cadaver, patient), target design, error type and subtypes, space of TPE measurement, statistics, and (b) image modality, scan parameters, tracking technology, registration procedure and targeting technique. Conclusions Adoption of the proposed standardized reporting may help in the understanding and comparability of different accuracy reports. Copyright © 2009 John Wiley & Sons, Ltd. [source] A robotic assistant for stereotactic neurosurgery on small animalsTHE INTERNATIONAL JOURNAL OF MEDICAL ROBOTICS AND COMPUTER ASSISTED SURGERY, Issue 4 2008L. Ramrath Abstract Background This work presents the development and performance analysis of a robotic system for stereotactic neurosurgery on small animals. The system is dedicated to the precise placement of probes in the small animal brain, thus providing an improved framework for brain research. Methods Based on an analysis of small animal stereotaxy, the mechanical design of the robotic system is presented. Details of the structure and mechanical components and a kinematic description are outlined. The calibration process of the system for arbitrary probes is described. To analyse the mechanical positioning accuracy of the system, a testbed is presented. Results Positioning performance results show that the system features a mean mechanical positioning accuracy of 32 µm and a mean positioning repeatability of 11 µm. Conclusion The system meets the requirements of targeting small functional areas within the brain of small animals and thus offers a new tool for small animal brain research. Copyright © 2008 John Wiley & Sons, Ltd. [source] Use of the NeuroMate stereotactic robot in a frameless mode for functional neurosurgery,THE INTERNATIONAL JOURNAL OF MEDICAL ROBOTICS AND COMPUTER ASSISTED SURGERY, Issue 2 2006T. R. K. Varma Abstract Background The aim of this paper is to describe the use of the NeuroMate stereotactic robot for functional neurosurgery with a novel frameless ultrasound registration system. Methods A retrospective review of the evaluation and clinical use of the NeuroMate stereotactic robot in a frameless mode for functional neurosurgery. Results Prior to its clinical use a phantom study was undertaken to demonstrate an application accuracy of 1.29 mm. Subsequently the robot has been used in 153 functional neurosurgical procedures including 113 deep brain stimulator implantations. Conclusions The NeuroMate stereotactic robot in a frameless mode has sufficient accuracy for a range of functional neurosurgical procedures, including movement disorder surgery. Copyright © 2006 John Wiley & Sons, Ltd. [source] Robotics in neurosurgery: state of the art and future technological challengesTHE INTERNATIONAL JOURNAL OF MEDICAL ROBOTICS AND COMPUTER ASSISTED SURGERY, Issue 1 2004L Zamorano Abstract The use of robotic technologies to assist surgeons was conceptually described almost thirty years ago but has only recently become feasible. In Neurosurgery, medical robots have been applied to neurosurgery for over 19 years. Nevertheless this field remains unknown to most neurosurgeons. The intrinsic characteristics of robots, such as high precision, repeatability and endurance make them ideal surgeon's assistants. Unfortunately, limitations in the current available systems make its use limited to very few centers in the world. During the last decade, important efforts have been made between academic and industry partnerships to develop robots suitable for use in the operating room environment. Although some applications have been successful in areas of laparoscopic surgery and orthopaedics, Neurosurgery has presented a major challenge due to the eloquence of the surrounding anatomy. This review focuses on the application of medical robotics in neurosurgery. The paper begins with an overview of the development of the medical robotics, followed by the current clinical applications in neurosurgery and an analysis of current limitations. We discuss robotic applications based in our own experience in the field. Next, we discuss the technological challenges and research areas to overcome those limitations, including some of our current research approaches for future progress in the field Copyright © 2004 Robotic Publications Ltd. [source] A prospective study of the time to evacuate acute subdural and extradural haematomas,ANAESTHESIA, Issue 3 2009D. Bulters Summary We performed a prospective, single-centre study of times to treatment of patients with life-threatening, traumatic, extra- and subdural haematomas requiring surgical evacuation between May 2006 and May 2007. The mean time to surgical decompression was 5.0 h and 32% were performed within 4 h. Patients who initially presented to a district hospital and required transfer for neurosurgery were decompressed in 5.4 h vs 3.7 h for those admitted directly. The current standard of surgical evacuation of all haematomas within 4 h is not being met. Delays were identified in every stage in the management of these patients and no single step was identified as the major cause. Initial treatment in district hospitals led to delays greater than the added driving time. There may be time savings from carrying out treatment steps in parallel instead of in series. [source] Wrong site neurosurgery , still a problemANAESTHESIA, Issue 1 2009S. Shinde No abstract is available for this article. [source] Clearing the cervical spine in unconscious adult trauma patients: A survey of practice in specialist centres in the UK,ANAESTHESIA, Issue 11 2004P. S. Jones Summary A postal questionnaire survey of neurosurgery and spinal injury departments in the UK was conducted to determine how they assessed the cervical spine in unconscious, adult trauma patients, and at what point immobilisation was discontinued. Of the 32 units contacted, 27 responded (response rate, 84%). Most centres had no protocols to guide initial imaging or when immobilisation devices should be removed. Most responding centres performed fewer than three plain radiographs, and most did not use computerised tomography routinely. Routine use of magnetic resonance imaging or dynamic flexion,extension fluoroscopy was rare, and few units regarded the latter as safe in unconscious patients. There was no consensus on when immobilisation of the cervical spine should be discontinued. Most centres that terminated immobilisation immediately after imaging did so on the basis of plain radiographs alone. Unconscious adult trauma patients remain at risk of inadequate assessment of potential cervical spine injuries. [source] | |||||||||||||||||||||||||||||||