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1.
Microsurgery ; 44(2): e31138, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38343009

RESUMEN

Following its initial description by Koshima in 2004, the superficial circumflex iliac artery perforator (SCIP) flap has become a ubiquitous and extremely useful flap in coverage of defects whereby bulkiness must be avoided. It also allows direct closure and concealment of the donor site. Its use as a free tissue transfer has been demonstrated by various surgeons globally. Nevertheless, there are few cases illustrating the utility of the pedicled SCIP flap in the reconstruction of lower abdominal defects. We present a case of a pedicled SCIP flap utilized as a chimeric flap incorporating external oblique muscle fascia on a deep branch along with the typical fasciocutaneous component based on the superficial branch to cover the suprapubic defect after vesicocutaneous fistula repair. We thereafter report on the literature of pedicled chimeric SCIP flap for locoregional reconstruction. A 26-year-old female was referred to the Plastic and Reconstructive Surgery unit after suffering a functional bladder outlet obstruction necessitating the creation of a urinary stoma. Subsequently, stoma obstruction occurred, and a suprapubic catheter was performed that was complicated by infection and resulted in the development of a vesicocutaneous fistula. Accordingly, the urological surgeons were planning surgical closure of the suprapubic vesicocutaneous defect, measuring 5 × 4 cm. A pedicled SCIP flap was designed to match the defect size; and raised as a chimeric flap with external oblique muscle fascia based on the deep branch, along with the fasciocutaneous component based on the superficial branch. The external oblique fascial component was used to secure the suture line of fistula repair, over which the fasciocutaneous component was inset, effectively double breasting the fistula repair and full thickness lower abdominal defect. The patient had an unremarkable postoperative recovery and has since been followed up in the outpatient setting without complication for the past 24 months. Robust coverage of the suprapubic defect was reliably achieved and no further fistulation has occurred. This case illustrates that a pedicled SCIP flap can be harvested as a chimeric flap and used to reliably cover defects in the infra-umbilical region.


Asunto(s)
Fístula , Colgajo Perforante , Procedimientos de Cirugía Plástica , Femenino , Humanos , Adulto , Arteria Ilíaca/cirugía , Vejiga Urinaria/cirugía , Colgajo Perforante/irrigación sanguínea , Fascia
2.
Phys Rev Lett ; 131(7): 075101, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37656860

RESUMEN

The fusion-born alpha particle heating in magnetically confined fusion machines is a high priority subject for studies. The self-heating of thermonuclear fusion plasma by alpha particles was observed in recent deuterium-tritium (D-T) experiments on the joint European torus. This observation was possible by conducting so-called "afterglow" experiments where transient high fusion yield was achieved with neutral beam injection as the only external heating source, and then termination of the heating at peak performance. This allowed the first direct evidence for electron heating of plasmas by fusion-born alphas to be obtained. Interpretive transport modeling of the relevant D-T and reference deuterium discharges is consistent with the alpha particle heating observation.

3.
Rev Sci Instrum ; 89(9): 093704, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30278741

RESUMEN

A cryo scanning transmission X-ray microscope, the cryo-STXM, has been designed and commissioned at the Canadian Light Source synchrotron. The instrument is designed to operate from 100 to 4000 eV (λ = 12.4 - 0.31 nm). Users can insert a previously frozen sample, through a load lock, and rotate it ±70° in the beam to collect tomographic data sets. The sample can be maintained for extended periods at 92 K primarily to suppress radiation damage and a pressure on the order of 10-9 Torr to suppress sample contamination. The achieved spatial resolution (30 nm) and spectral resolution (0.1 eV) are similar to other current soft X-ray STXMs, as demonstrated by measurements on known samples and test patterns. The data acquisition efficiency is significantly more favorable for both imaging and tomography. 2D images, 3D tomograms, and 4D chemical maps of automotive hydrogen fuel cell thin sections are presented to demonstrate current performance and new capabilities, namely, cryo-spectrotomography in the soft X-ray region.

4.
Bone Joint J ; 100-B(3): 396-403, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29589503

RESUMEN

Aims: The aim of this study was to report the clinical, functional and radiological outcomes of children and adolescents with tibial fractures treated using the Ilizarov method. Patients and Methods: Between 2013 and 2016 a total of 74 children with 75 tibial fractures underwent treatment at our major trauma centre using an Ilizarov frame. Demographic and clinical information from a prospective database was supplemented by routine functional and psychological assessment and a retrospective review of the notes and radiographs. Results: Of the 75 fractures, 26 (35%) were open injuries, of which six (8%) had segmental bone loss. There were associated physeal injuries in 18 (24%), and 12 (16%) involved conversion of treatment following failure of previous management. The remaining children had a closed unstable fracture or significant soft-tissue compromise. The median follow-up was 16 months (7 to 31). All fractures united with a median duration in a frame of 3.6 months (interquartile range 3.1 to 4.6); there was no significant difference between the types of fracture and the demographics of the patients. There were no serious complications and no secondary procedures were required to achieve union. Health-related quality of life measures were available for 60 patients (80%) at a minimum of six months after removal of the frame. These indicated a good return to function (median Paediatric quality of life score, 88.0; interquartile range 70.3 to 100). Conclusion: The Ilizarov method is a safe, effective and reliable method for the treatment of complex paediatric tibial fractures. Cite this article: Bone Joint J 2018;100-B:396-403.


Asunto(s)
Técnica de Ilizarov , Fracturas de la Tibia/cirugía , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Estudios Prospectivos , Calidad de Vida , Estudios Retrospectivos , Resultado del Tratamiento
5.
Eur Psychiatry ; 37: 43-8, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27447102

RESUMEN

BACKGROUND: Clinical trial outcomes are heavily influenced by the non-naturalistic clinical trial process. Observations of outcomes in clinical practice are a valuable adjunct to clinical trial results. HYPOTHESIS: Our null hypothesis was that clinically indicated switching to paliperidone palmitate had no effect on hospital admissions or hospital bed days. METHOD: This was a part-prospective mirror image study examining outcomes 2years before starting paliperidone palmitate and 2years after. Sensitivity analyses examined the effect of different placings of the mirror in the mirror image design. RESULTS: We prospectively followed-up 225 patients prescribed paliperidone palmitate in clinical practice. At 2years, 41.8% of patients were still receiving paliperidone palmitate. In the primary analysis, the mean number of admissions fell from 1.80 in the two years before starting paliperidone palmitate to 0.81 in two years following the drug's initiation (outpatients) or two years following hospital discharge (inpatients) (P<0.001). More than half of patients were not admitted to hospital during two years follow-up. Mean total bed days was reduced from 79.6 in the two years before to 46.2 in the two years after paliperidone palmitate initiation or discharge (P<0.001). Sensitivity analyses gave broadly similar outcomes. Continuers demonstrated better outcomes than discontinuers in sensitivity analyses but not in the primary analysis. CONCLUSION: Paliperidone palmitate initiation is associated with a substantial reduction in hospital admissions and days spent in hospital. The reduction in costs associated with reduced use of health care facilities is likely to exceed the purchase and administration costs of the drug.


Asunto(s)
Hospitalización/estadística & datos numéricos , Palmitato de Paliperidona/uso terapéutico , Esquizofrenia/terapia , Adulto , Antipsicóticos/uso terapéutico , Femenino , Humanos , Masculino , Evaluación de Procesos y Resultados en Atención de Salud , Estudios Prospectivos , Reino Unido
6.
J Neural Eng ; 12(4): 046031, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26170261

RESUMEN

OBJECTIVE: Decoding algorithms for brain-machine interfacing (BMI) are typically only optimized to reduce the magnitude of decoding errors. Our goal was to systematically quantify how four characteristics of BMI command signals impact closed-loop performance: (1) error magnitude, (2) distribution of different frequency components in the decoding errors, (3) processing delays, and (4) command gain. APPROACH: To systematically evaluate these different command features and their interactions, we used a closed-loop BMI simulator where human subjects used their own wrist movements to command the motion of a cursor to targets on a computer screen. Random noise with three different power distributions and four different relative magnitudes was added to the ongoing cursor motion in real time to simulate imperfect decoding. These error characteristics were tested with four different visual feedback delays and two velocity gains. MAIN RESULTS: Participants had significantly more trouble correcting for errors with a larger proportion of low-frequency, slow-time-varying components than they did with jittery, higher-frequency errors, even when the error magnitudes were equivalent. When errors were present, a movement delay often increased the time needed to complete the movement by an order of magnitude more than the delay itself. Scaling down the overall speed of the velocity command can actually speed up target acquisition time when low-frequency errors and delays are present. SIGNIFICANCE: This study is the first to systematically evaluate how the combination of these four key command signal features (including the relatively-unexplored error power distribution) and their interactions impact closed-loop performance independent of any specific decoding method. The equations we derive relating closed-loop movement performance to these command characteristics can provide guidance on how best to balance these different factors when designing BMI systems. The equations reported here also provide an efficient way to compare a diverse range of decoding options offline.


Asunto(s)
Interfaces Cerebro-Computador , Retroalimentación Sensorial/fisiología , Movimiento/fisiología , Desempeño Psicomotor/fisiología , Tiempo de Reacción/fisiología , Percepción Visual/fisiología , Transferencia de Energía , Femenino , Humanos , Almacenamiento y Recuperación de la Información/métodos , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Factores de Tiempo
7.
Acta Psychiatr Scand ; 130(6): 452-69, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25283309

RESUMEN

OBJECTIVE: Treatment of bipolar depression is complicated by variable response and risk of switch to mania. Guidance is informed by the strength of evidence rather than by comparative data. METHOD: We performed a multiple-treatments meta-analysis of randomised, double-blind, controlled comparisons of 4-16 weeks in adults in bipolar depression. The primary efficacy outcome was effect size. The primary acceptability outcome was 'switch to mania'. Secondary outcomes were likelihood of response and withdrawals from trials. RESULTS: Twenty-nine studies were included (8331 participants). Olanzapine + fluoxetine and olanzapine performed best on primary outcome measure being ranked highest for effect size. Switch to mania was least likely with ziprasidone and then quetiapine. Olanzapine + fluoxetine was also ranked the highest for response with lurasidone second, but olanzapine + fluoxetine and olanzapine had the optimal effect on response and withdrawal from treatment when the two parameters were considered together. Several treatments [monoamine oxidase inhibitors (MAOIs), ziprasidone, aripiprazole and risperidone] have limited or no therapeutic activity in bipolar depression. CONCLUSION: Olanzapine + fluoxetine should be first-line treatment. Olanzapine, quetiapine, lurasidone, valproate and selective serotonin re-uptake inhibitors are also recommended. Tricyclic antidepressants and lithium are worthy of consideration but lamotrigine (high risk of switching, less robust efficacy) and MAOIs, ziprasidone, aripiprazole and risperidone (no evidence of efficacy) should not be used.


Asunto(s)
Antidepresivos/uso terapéutico , Antipsicóticos/uso terapéutico , Trastorno Bipolar/tratamiento farmacológico , Depresión/tratamiento farmacológico , Adulto , Aripiprazol , Benzodiazepinas/uso terapéutico , Trastorno Bipolar/psicología , Depresión/psicología , Dibenzotiazepinas/uso terapéutico , Quimioterapia Combinada , Fluoxetina/uso terapéutico , Humanos , Isoindoles/uso terapéutico , Lamotrigina , Compuestos de Litio/uso terapéutico , Clorhidrato de Lurasidona , Inhibidores de la Monoaminooxidasa/uso terapéutico , Olanzapina , Piperazinas/uso terapéutico , Fumarato de Quetiapina , Quinolonas/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto , Risperidona/uso terapéutico , Inhibidores Selectivos de la Recaptación de Serotonina/uso terapéutico , Tiazoles/uso terapéutico , Resultado del Tratamiento , Triazinas/uso terapéutico , Ácido Valproico/uso terapéutico
8.
J R Nav Med Serv ; 100(2): 152-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25335309

RESUMEN

AIMS: A frequently-seen injury pattern in current military experience is traumatic lower limb amputation as a result of improvised explosive devices (IEDs). This injury can coexist with fractures involving the pelvic ring. This study aims to assess the frequency of concomitant pelvic fracture in IED-related lower limb amputation. METHODS: A retrospective analysis of the trauma charts, medical notes, and digital imaging was undertaken for all patients arriving at the Emergency Department at the UK military field hospital in Camp Bastion, Afghanistan, with a traumatic lower limb amputation in the six months between September 2009 and April 2010, in order to determine the incidence of associated pelvic ring fractures. RESULTS: Of 77 consecutive patients with traumatic lower limb amputations, 17 (22%) had an associated pelvic fracture (eleven with displaced pelvic ring fractures, five undisplaced fractures and one acetabular fracture). Unilateral amputees (n = 31) had a 10% incidence of associated pelvic fracture, whilst 30 % of bilateral amputees (n = 46) had a concurrent pelvic fracture. However, in bilateral, trans-femoral amputations (n = 28) the incidence of pelvic fracture was 39%. CONCLUSIONS: The study demonstrates a high incidence of pelvic fractures in patients with traumatic lower limb amputations, supporting the routine pre-hospital application of pelvic binders in this patient group.


Asunto(s)
Amputación Traumática/epidemiología , Traumatismos por Explosión/epidemiología , Fracturas Óseas/epidemiología , Extremidad Inferior/lesiones , Personal Militar/estadística & datos numéricos , Huesos Pélvicos/lesiones , Campaña Afgana 2001- , Afganistán/epidemiología , Amputación Traumática/complicaciones , Bombas (Dispositivos Explosivos) , Fracturas Óseas/complicaciones , Humanos , Incidencia , Estudios Retrospectivos
9.
Eur J Clin Pharmacol ; 70(12): 1513-8, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25270975

RESUMEN

PURPOSE: To evaluate reported ingested dose of paracetamol as a risk assessment tool in acute paracetamol overdose. METHODS: Data was retrospectively obtained from a clinical toxicology database linked to one Australian and two United Kingdom hospitals. Plasma paracetamol concentrations (PPCs) of adult patients presenting with acute single ingestion, non-staggered paracetamol deliberate self-poisoning between 2006 and 2012 were recorded and plotted on a treatment nomogram to determine accuracy of reported dose ingested as an indicator for antidotal treatment. PPC plotted on a treatment nomogram with a line intersecting a 4-h concentration of 100 mg/L [667 µmol/L] was considered an indication for antidotal treatment in the UK; the corresponding Australasian population utilised a line intersecting 150 mg/L [1000 µmol/L]. RESULTS: Of 1246 patients, 65.7 % were female and 88 % were from the UK. Fifty-two percent of patients reporting ingestion of ≥8 g paracetamol had a PPC above the 100 mg/L treatment line; PPV 52 % [95 % confidence interval (CI) 49 %, 55 %], sensitivity 81 % [95 %CI 78 %, 85 %]. Forty-four of patients reporting percent ingestion of ≥10 g had a PPC above the 150 mg/L treatment line; PPV 44 % [95 % CI 41 %, 49 %], sensitivity 85 % [95 % CI 78 %, 89 %], 72 % of patients reporting ingestion of ≥16 g had a PPC above the 100 mg/L treatment line; PPV 72 % [95% CI 67 %, 77 %], sensitivity 50 % [95 % CI 45 %, 54 %]. Overall, there was moderate correlation (R = 0.58) between reported paracetamol dose ingested and extrapolated 4-h PPC. CONCLUSIONS: There is a positive correlation between reported ingested dose of paracetamol and subsequent chance of a PPC being above a defined treatment line; however, ingested dose of paracetamol alone is a poor risk assessment tool in accurately determining need for treatment with an antidote.


Asunto(s)
Acetaminofén/sangre , Analgésicos no Narcóticos/sangre , Sobredosis de Droga/sangre , Autoinforme , Acetaminofén/administración & dosificación , Acetaminofén/envenenamiento , Acetilcisteína/uso terapéutico , Adulto , Analgésicos no Narcóticos/administración & dosificación , Analgésicos no Narcóticos/envenenamiento , Antídotos/uso terapéutico , Sobredosis de Droga/tratamiento farmacológico , Femenino , Humanos , Masculino , Riesgo , Adulto Joven
10.
J Neural Eng ; 10(3): 036015, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23611833

RESUMEN

OBJECTIVE: Our goal was to identify spatial filtering methods that would improve decoding of continuous arm movements from epidural field potentials as well as demonstrate the use of the epidural signals in a closed-loop brain-machine interface (BMI) system in monkeys. APPROACH: Eleven spatial filtering options were compared offline using field potentials collected from 64-channel high-density epidural arrays in monkeys. Arrays were placed over arm/hand motor cortex in which intracortical microelectrodes had previously been implanted and removed leaving focal cortical damage but no lasting motor deficits. Spatial filters tested included: no filtering, common average referencing (CAR), principle component analysis, and eight novel modifications of the common spatial pattern (CSP) algorithm. The spatial filtering method and decoder combination that performed the best offline was then used online where monkeys controlled cursor velocity using continuous wrist position decoded from epidural field potentials in real time. MAIN RESULTS: Optimized CSP methods improved continuous wrist position decoding accuracy by 69% over CAR and by 80% compared to no filtering. Kalman decoders performed better than linear regression decoders and benefitted from including more spatially-filtered signals but not from pre-smoothing the calculated power spectra. Conversely, linear regression decoders required fewer spatially-filtered signals and were improved by pre-smoothing the power values. The 'position-to-velocity' transformation used during online control enabled the animals to generate smooth closed-loop movement trajectories using the somewhat limited position information available in the epidural signals. The monkeys' online performance significantly improved across days of closed-loop training. SIGNIFICANCE: Most published BMI studies that use electrocorticographic signals to decode continuous limb movements either use no spatial filtering or CAR. This study suggests a substantial improvement in decoding accuracy could be attained by using our new version of the CSP algorithm that extends the traditional CSP method for use with continuous limb movement data.


Asunto(s)
Brazo/fisiología , Interfaces Cerebro-Computador , Electrodos Implantados , Electroencefalografía/métodos , Potenciales Evocados Motores/fisiología , Corteza Motora/fisiología , Movimiento/fisiología , Algoritmos , Animales , Electroencefalografía/instrumentación , Haplorrinos , Procesamiento de Señales Asistido por Computador
11.
Injury ; 43(7): 1037-40, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22236366

RESUMEN

INTRODUCTION: The operative workload at the surgical facility in Camp Bastion, Afghanistan, has previously been reported for the two-year period 1 May 2006 to 1 May 2008. There have since been considerable changes not only in the casualty rates, but also in the injury patterns encountered. Severe wounds from improvised explosive devices (IEDs) have become the signature injury of the insurgency. We present recent data for the surgical activity at the Joint Forces Medical Group Role 3 Hospital, Camp Bastion, for the two-year period 1 November 2008 to 1 November 2010. PATIENTS AND METHODS: A retrospective analysis of the operating theatre logbooks was undertaken for the period 1 November, 2008 to 1 November, 2010. RESULTS: During the study period a total of 4276 cases required 5737 surgical procedures. Compared with the previously reported series from May 2006 to 2008, this represents a 2.6-fold increase in the surgical workload of the hospital. There has been a 5.7-fold increase in the number of amputations (483 during this study period, 8.4% all operative procedures), and for the lower limbs these have become increasingly proximal (48% all amputations were above-knee lower limb amputations). During the study period there were also significant increases in the frequency of perineal injuries as well as the numbers of cases involving 5 or more surgeons. DISCUSSION: The surgical workload at the Role 3 Hospital, Camp Bastion, Afghanistan is increasing. This is a result not only of increasing casualty numbers but also of increasingly severe injury patterns. With the growing use of powerful IEDs, traumatic lower limb amputations in particular are becoming more common, and are increasingly associated with significant pelvic and perineal injury. These complex injury patterns necessitate a multi-surgeon approach, and it is important these trends are noted for future planning of medical support to military operations in Afghanistan.


Asunto(s)
Amputación Quirúrgica/estadística & datos numéricos , Traumatismos por Explosión/epidemiología , Hospitales Militares/organización & administración , Medicina Militar/organización & administración , Traumatismo Múltiple/epidemiología , Carga de Trabajo/estadística & datos numéricos , Adulto , Campaña Afgana 2001- , Afganistán/epidemiología , Traumatismos por Explosión/cirugía , Femenino , Hospitales Militares/estadística & datos numéricos , Humanos , Masculino , Medicina Militar/estadística & datos numéricos , Personal Militar , Traumatismo Múltiple/cirugía , Estudios Retrospectivos , Recursos Humanos , Adulto Joven
12.
Acta Psychiatr Scand ; 125(1): 15-24, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22077319

RESUMEN

OBJECTIVE: To examine using meta-analysis the effect of adding a second antipsychotic to established clozapine monotherapy. METHOD: A literature search was conducted in April 2011, and randomised placebo-controlled double-blind studies were identified. We performed a meta-analysis of efficacy (as standardised mean difference) and tolerability (withdrawals from trials) and a regression analysis of duration of study versus effect size. We also examined publication bias using funnel-plot analysis. RESULTS: Overall, 14 studies were included (734 subjects). Individual study numbers ranged from 10 to 207 (mean 52.6, median 40). Augmentation of clozapine with a second antipsychotic conferred a small benefit over placebo (effect size -0.239 (95% CI: -0.452, -0.026); P = 0.028). Meta-regression of the effect of length of treatment on effect size showed no relationship (P = 0.254). The risk of discontinuing antipsychotic augmentation was no greater than the risk of discontinuing placebo (RR = 1.20, 95% CI 0.80-1.82). There was no evidence of publication bias. CONCLUSION: Augmentation with a second antipsychotic is modestly beneficial in patients not responding fully to clozapine. Tolerability seems not to be adversely affected, at least in the short term. Longer studies do not appear to increase the probability of showing positive effects for augmentation.


Asunto(s)
Antipsicóticos , Clozapina , Quimioterapia Combinada/métodos , Esquizofrenia/tratamiento farmacológico , Antipsicóticos/farmacocinética , Antipsicóticos/uso terapéutico , Bibliometría , Clozapina/farmacocinética , Clozapina/uso terapéutico , Sinergismo Farmacológico , Tolerancia a Medicamentos , Humanos , Evaluación de Resultado en la Atención de Salud , Ensayos Clínicos Controlados Aleatorios como Asunto , Equivalencia Terapéutica , Factores de Tiempo
13.
Intern Med J ; 42(6): 672-6, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22032242

RESUMEN

BACKGROUND: Anti-glomerular basement membrane (GBM) antibody-mediated disease is rare and classically presents with the syndrome of glomerulonephritis and pulmonary haemorrhage. AIM: This aim of this report was to determine the incidence, clinical features, management and outcomes of anti-GBM disease in Auckland between 1998 and 2008. METHODS: Potential patients were identified by a search for positive anti-GBM antibody serology, diagnostic renal biopsy, or in-hospital admissions using International Classification of Diseases 9 and 10 codes between 1998 and 2008. A retrospective case notes review of all potential cases was performed with data censored at 31 December 2010. RESULTS: Twenty-three cases were identified. The rate of anti-GBM disease was estimated at 1.79 per million person-years. There were 12 men and 11 women. The median age was 45 years, range 12-74 years. Sixteen patients were European, three were Pacific peoples, three were NZ Maori and one was Chinese. Eleven were regular smokers and eight ex-smokers, significantly higher proportions than the population (P ≤ 0.001). Smokers were significantly more likely to have respiratory disease (P= 0.03). The mean creatinine at presentation was 474 µmol/L. All patients had a renal biopsy; 20 had crescentic glomerulonephritis. One patient recovered renal function without treatment. Twenty-two were immunosuppressed with cyclophosphamide and corticosteroids. Seventeen received plasmapheresis. Eighteen were alive, eight with end-stage renal disease, two with chronic kidney disease and eight with normal renal function. CONCLUSIONS: Anti-GBM disease is a rare condition, which is not overrepresented among indigenous people. With aggressive therapy the prognosis has improved; however, the morbidity and mortality of this condition remain significant.


Asunto(s)
Glomerulonefritis/epidemiología , Hemorragia/epidemiología , Enfermedades Pulmonares/epidemiología , Adolescente , Adulto , Anciano , Membrana Basal , Niño , Terapia Combinada , Creatinina/sangre , Ciclofosfamida/administración & dosificación , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Glomerulonefritis/sangre , Glomerulonefritis/diagnóstico , Glomerulonefritis/terapia , Hemorragia/sangre , Hemorragia/diagnóstico , Hemorragia/terapia , Humanos , Inmunosupresores/administración & dosificación , Incidencia , Glomérulos Renales , Enfermedades Pulmonares/sangre , Enfermedades Pulmonares/diagnóstico , Enfermedades Pulmonares/terapia , Masculino , Persona de Mediana Edad , Nueva Zelanda/epidemiología , Plasmaféresis , Diálisis Renal , Fumar/epidemiología , Adulto Joven
14.
J Neural Eng ; 8(4): 046022, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21712569

RESUMEN

Paralyzed individuals can control the movement of an assistive device using changes in electroencephalographic (EEG) power resulting from attempted movements. Simultaneous, proportional control of two-dimensional (2D) device movements can be achieved with the concurrent modulation of brain activity that is associated with the attempted movement and rest of two independent body parts. Movement control may be improved by spatial filtering methods that recombine raw EEGs to form new signals with more focused information about the underlying brain activity. This study compared spatial filters offline for improving simultaneous proportional 2D movement commands from EEGs. Filtering options evaluated were common average referencing, Laplacian, independent component analysis, principle component analysis, and two novel ways of applying common spatial pattern (CSP) analysis. CSP analysis is a supervised algorithm that optimally recombines EEGs collected under two known conditions. Both CSP options resulted in more accurate movement prediction than the other filtering options. CSP was particularly advantageous when separating EEGs associated with neighboring or overlapping areas on the motor homunculus. Finally, CSP performed well using smaller subsets of filtered signals, thus making CSP practical and efficient for simultaneous 2D control. A 2D online cursor control example using CSP filtering is included to show CSP's utility.


Asunto(s)
Electroencefalografía/métodos , Electroencefalografía/estadística & datos numéricos , Movimiento/fisiología , Interfaz Usuario-Computador , Algoritmos , Encéfalo/fisiología , Mapeo Encefálico , Corteza Cerebral/fisiología , Señales (Psicología) , Interpretación Estadística de Datos , Humanos , Modelos Lineales , Corteza Motora , Parálisis/rehabilitación , Análisis de Componente Principal , Procesamiento de Señales Asistido por Computador , Traumatismos de la Médula Espinal/rehabilitación
15.
J Neural Eng ; 8(4): 046003, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21623009

RESUMEN

Movement-assist devices such as neuromuscular stimulation systems can be used to generate movements in people with chronic hand paralysis due to stroke. If detectable, motor planning activity in the cortex could be used in real time to trigger a movement-assist device and restore a person's ability to perform many of the activities of daily living. Additionally, re-coupling motor planning in the cortex with assisted movement generation in the periphery may provide an even greater benefit-strengthening relevant synaptic connections over time to promote natural motor recovery. This study examined the potential for using electroencephalograms (EEGs) as a means of rapidly detecting the intent to open the hand during movement planning in individuals with moderate chronic hand paralysis following a subcortical ischemic stroke. On average, attempts to open the hand could be detected from EEGs approximately 100-500 ms prior to the first signs of movement onset. This earlier detection would minimize device activation delays and allow for tighter coupling between initial formation of the motor plan in the cortex and augmentation of that plan in the periphery by a movement-assist device. This tight temporal coupling may be important or even essential for strengthening synaptic connections and enhancing natural motor recovery.


Asunto(s)
Electroencefalografía/métodos , Mano/fisiología , Movimiento/fisiología , Rehabilitación de Accidente Cerebrovascular , Actividades Cotidianas , Isquemia Encefálica/complicaciones , Isquemia Encefálica/rehabilitación , Señales (Psicología) , Interpretación Estadística de Datos , Estimulación Eléctrica , Electromiografía , Reacciones Falso Positivas , Dedos/fisiología , Humanos , Plasticidad Neuronal/fisiología , Parálisis/rehabilitación , Estimulación Luminosa , Recuperación de la Función , Accidente Cerebrovascular/etiología , Sinapsis/fisiología
16.
J Neural Eng ; 8(3): 034003, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21543840

RESUMEN

Functional electrical stimulation (FES), the coordinated electrical activation of multiple muscles, has been used to restore arm and hand function in people with paralysis. User interfaces for such systems typically derive commands from mechanically unrelated parts of the body with retained volitional control, and are unnatural and unable to simultaneously command the various joints of the arm. Neural interface systems, based on spiking intracortical signals recorded from the arm area of motor cortex, have shown the ability to control computer cursors, robotic arms and individual muscles in intact non-human primates. Such neural interface systems may thus offer a more natural source of commands for restoring dexterous movements via FES. However, the ability to use decoded neural signals to control the complex mechanical dynamics of a reanimated human limb, rather than the kinematics of a computer mouse, has not been demonstrated. This study demonstrates the ability of an individual with long-standing tetraplegia to use cortical neuron recordings to command the real-time movements of a simulated dynamic arm. This virtual arm replicates the dynamics associated with arm mass and muscle contractile properties, as well as those of an FES feedback controller that converts user commands into the required muscle activation patterns. An individual with long-standing tetraplegia was thus able to control a virtual, two-joint, dynamic arm in real time using commands derived from an existing human intracortical interface technology. These results show the feasibility of combining such an intracortical interface with existing FES systems to provide a high-performance, natural system for restoring arm and hand function in individuals with extensive paralysis.


Asunto(s)
Brazo/fisiopatología , Electroencefalografía/métodos , Modelos Neurológicos , Corteza Motora/fisiopatología , Red Nerviosa/fisiopatología , Cuadriplejía/fisiopatología , Cuadriplejía/rehabilitación , Brazo/inervación , Biomimética/métodos , Simulación por Computador , Terapia por Estimulación Eléctrica/métodos , Potenciales Evocados Motores , Humanos , Movimiento , Músculo Esquelético/inervación , Músculo Esquelético/fisiopatología
17.
Injury ; 42(10): 1112-5, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21354568

RESUMEN

The use of ring fixators in lower limb reconstruction and deformity correction both for trauma and elective procedures is now widespread. The long course of treatment requires regular outpatient review with frequent radiological imaging to assess the progression of treatment and plan correctional adjustment. Following publication of a technique using a frame mounted spirit-level to aid radiographers in accurately aligning the limb for optimal imaging we implemented a similar technique in our department and carried out a two part prospective comparative study to assess the impact on radiograph quality. Comparison was made of radiograph quality, X-rays taken, patient trips to the radiology department and X-ray exposure before and after implementation of the spirit-level guide technique in patients attending an out-patient clinic for routine follow up following ring fixator application. 26 patients were included in the control arm and 33 in the intervention group. On review, 42.3% of patients in the control group were deemed to have had suboptimal imaging compared with only 9.1% of those imaged using the spirit-level guide, a statistically significant improvement. When comparing total numbers of images taken for each group to achieve the requested number of adequate views there was less statistical significance, nor was there a statistically significant difference in radiation dose between the groups. A significant reduction in the number of inadequate images being taken, with a subsequent reduction in patients requiring return to the radiology department for re-imaging and then re-review in clinic, has clear implications for patients, clinicians and hospital efficiency. The patient journey time is reduced, less time and fewer resources are used in the radiology department and patients in clinic are seen more efficiently and with less wasted time. We conclude that the implementation of a simple frame mounted spirit-level as a guide for radiographers in the outpatient clinic significantly reduces the number of suboptimal and wasted images taken in the assessment of patients being treated by ring fixator.


Asunto(s)
Técnica de Ilizarov/instrumentación , Radiografía/instrumentación , Fracturas de la Tibia/cirugía , Hilos Ortopédicos , Diseño de Equipo , Humanos , Servicio Ambulatorio en Hospital , Estudios Prospectivos , Mejoramiento de la Calidad , Dosis de Radiación , Fracturas de la Tibia/diagnóstico por imagen
18.
J Neural Eng ; 8(2): 025016, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21436529

RESUMEN

Arm end-point position, end-point velocity, and the intended final location or 'goal' of a reach have all been decoded from cortical signals for use in brain-machine interface (BMI) applications. These different aspects of arm movement can be decoded from the brain and used directly to control the position, velocity, or movement goal of a device. However, these decoded parameters can also be remapped to control different aspects of movement, such as using the decoded position of the hand to control the velocity of a device. People easily learn to use the position of a joystick to control the velocity of an object in a videogame. Similarly, in BMI systems, the position, velocity, or goal of a movement could be decoded from the brain and remapped to control some other aspect of device movement. This study evaluates how easily people make transformations between position, velocity, and reach goal in BMI systems. It also evaluates how different amounts of decoding error impact on device control with and without these transformations. Results suggest some remapping options can significantly improve BMI control. This study provides guidance on what remapping options to use when various amounts of decoding error are present.


Asunto(s)
Algoritmos , Mapeo Encefálico/métodos , Electroencefalografía/métodos , Potenciales Evocados Motores/fisiología , Corteza Motora/fisiología , Movimiento/fisiología , Análisis y Desempeño de Tareas , Humanos , Reconocimiento de Normas Patrones Automatizadas/métodos , Interfaz Usuario-Computador
20.
Ann R Coll Surg Engl ; 92(5): 411-6, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20487591

RESUMEN

INTRODUCTION: The management of complex extremity injury, which may require assessment of limb viability and performance of amputation, is a challenge to those involved in its emergent and definitive care. Concern exists regarding the exposure of orthopaedic trainees to such cases due both to changes in training and centralisation of trauma services. SUBJECTS AND METHODS: This is a web-based observational study by survey, investigating the confidence and perceived adequacy of training of UK orthopaedic specialist trainees in the assessment of limb viability and amputation surgery. 222 responses from 888 trainees were required to achieve a < 5% error rate with 90% confidence; 232 surveys were completed. RESULTS: Trainee confidence in dealing with the assessment of limb viability is high despite infrequent exposure to cases. The majority of trainees perceive their training in limb viability assessment as adequate. For performance of amputation, exposure is minimal, confidence is lower and 36% of trainees regard their training as inadequate. CONCLUSIONS: Limb viability assessment is an area in which trainees feel confident and well trained. There is, however, a perceived training inadequacy in amputation surgery and a corresponding lack of confidence for many trainees, irrespective of training year. This is the first study to offer an insight into specific training experiences of junior orthopaedic surgeons at a national level and it should drive the development of opportunities for trainees to develop skills in amputation surgery.


Asunto(s)
Amputación Quirúrgica/educación , Educación de Postgrado en Medicina/métodos , Recuperación del Miembro/educación , Ortopedia/educación , Traumatología/educación , Traumatismos del Brazo/cirugía , Actitud del Personal de Salud , Competencia Clínica , Educación de Postgrado en Medicina/normas , Humanos , Traumatismos de la Pierna/cirugía , Reino Unido
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