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Despite the scientific evidence, most families of people with schizophrenia in Europe never receive a carer education programme. We evaluated whether a carer education course delivered by telepsychiatry was as effective as a carer education course delivered in situ.
We delivered the carer education course for schizophrenia simultaneously to a carers group in rural north west Ireland (remote) via three ISDN lines and live to a carers group in a city (host). We compared knowledge gains using the Knowledge Questionnaire before and after each course.
Fifty-six carers of people with schizophrenia participated in the trial. At baseline, participants at the remote and host centers did not differ in terms of knowledge about schizophrenia. After the course, carers at both centers improved significantly and the knowledge gains between groups were equivalent at 6 weeks.
Telepsychiatry can deliver effective carer education programmes about schizophrenia and may provide one solution to bridging the chasm between scientific evidence and clinical reality.
Duchenne muscular dystrophy is associated with progressive cardiorespiratory failure, including left ventricular dysfunction.
Methods and Results:
Males with probable or definite diagnosis of Duchenne muscular dystrophy, diagnosed between 1 January, 1982 and 31 December, 2011, were identified from the Muscular Dystrophy Surveillance Tracking and Research Network database. Two non-mutually exclusive groups were created: patients with ≥2 echocardiograms and non-invasive positive pressure ventilation-compliant patients with ≥1 recorded ejection fraction. Quantitative left ventricular dysfunction was defined as an ejection fraction <55%. Qualitative dysfunction was defined as mild, moderate, or severe. Progression of quantitative left ventricular dysfunction was modelled as a continuous time-varying outcome. Change in qualitative left ventricle function was assessed by the percentage of patients within each category at each age. Forty-one percent (n = 403) had ≥2 ejection fractions containing 998 qualitative assessments with a mean age at first echo of 10.8 ± 4.6 years, with an average first ejection fraction of 63.1 ± 12.6%. Mean age at first echo with an ejection fraction <55 was 15.2 ± 3.9 years. Thirty-five percent (140/403) were non-invasive positive pressure ventilation-compliant and had ejection fraction information. The estimated rate of decline in ejection fraction from first ejection fraction was 1.6% per year and initiation of non-invasive positive pressure ventilation did not change this rate.
In our cohort, we observed that left ventricle function in patients with Duchenne muscular dystrophy declined over time, independent of non-invasive positive pressure ventilation use. Future studies are needed to examine the impact of respiratory support on cardiac function.
In theories of the heating of the solar corona a number of authors have recently considered the propagation and damping of fast and slow magnetohydrodynamic waves, in the form of surface waves localized on the interfaces of coronal flux tubes (Ionson 1978, Wentzel 1979, Roberts 1981, Cramer and Donnelly 1983). The damping of these waves occurs, in addition to a rather weak global damping due to viscous or resistive dissipation, by means of a localized absorption at a so-called ‘resonance’ in the density or magnetic field profile forming the flux tube. At such a resonance, the wave frequency is equal to the local value of the Alfven wave frequency, in the case of Alfven resonance absorption, or at the local slow mhd wave frequency, in the case of the ‘cusp’ or ‘compressive singularity’ resonance in a finite pressure plasma.
A common form of wave propagation in the highly structured magnetic fields and density profiles of the solar atmosphere should be magnetohydrodynamic surface waves, i.e. waves with magnetic and velocity fields concentrated at an interface of two regions of plasma of differing properties. For example, local concentrations of equilibrium magnetic fields forming flux tubes will support these waves on their surfaces, in addition to the more commonly considered ‘body waves’ that are supported by an isolated flux tube, waves with an oscillatory radial dependence inside the tube. Mhd surface waves have recently been identified in a laboratory plasma at Sydney University (Collins, Cramer and Donnelly 1983).
The resistive tearing mode instability is a mechanism that in some cases will render unstable a magnetohydrodynamic equilibrium of a plasma that is ideally stable, i.e. stable if no dissipative oiesses are taken into account. There is much experimental evidence that this instability is the cause of the current disruptions observed in laboratory plasma devices (von Goeler et al. 1974). In the astrophysical context, the instability has been invoked in connection with the solar flare energy release mechanism (Coppi and Friedland 1971) and the problem of the disconnection of the protostar matter from the interstellar magnetic field during star formation (Mestel 1966). In the latter problem the tearing instability gives rise to a much smaller timescale for magnetic reconnection than does ordinary resistive diffusion.
This study aimed (1) to report the long-term effects of infliximab, a murine monoclonal antibody directed against tumour necrosis factor-α, on autoimmune inner ear disease, and (2) to discuss dilemmas surrounding the long-term management of autoimmune inner ear disease.
A 49-year-old man presented with sudden-onset, left-sided, sensorineural hearing loss, tinnitus and vertigo. He was prescribed oral prednisolone, with benefit. Over several subsequent months, he experienced frequent relapses and progressive deterioration of high-frequency hearing bilaterally. Multiple agents failed to stabilise his condition. Following infliximab treatment, there was a documented and sustained improvement in his hearing and tinnitus. He stopped the treatment after 46 weeks, with rapid relapse of his condition. His hearing recovered quickly again after recommencing infliximab.
The benefits of prolonged infliximab use and potential side effects must be balanced against allowing the disease to take its course, with progressive deafness. Randomised controlled trials are required to assess infliximab's optimal duration of use, long-term efficacy and safety in the treatment of autoimmune inner ear disease.
This study aimed to determine whether there was a difference in skin permeability to methylene blue dye or skin morphology between dairy cows that differed in their susceptibility to digital dermatitis (DD) and to assess the effect of contact with slurry on skin permeability. Twenty nine dairy cows were monitored for DD during the winter housing period and classed as DD+ (previous DD infection, n = 17), or DD− (no recorded infection, n = 12). The animals were culled and a skin sample was taken from above the heel of each hind foot and frozen. Samples were later defrosted and one sample from each cow was tested for permeability, whereas the other was treated with slurry for 24 h before permeability testing. To test permeability, methylene blue dye was applied to the skin surface in a Franz diffusion cell. After 48 h, the amount of dye that had passed through the skin was estimated. The stratum corneum thickness and the density of hair follicles were determined from additional heel skin samples. Skin permeability to methylene blue dye was significantly greater for samples that had been treated with slurry but did not differ between DD+ and DD− animals. No difference was found in the stratum corneum thickness or density of hair follicles between DD+ and DD− animals. These findings imply that individual differences in general skin permeability are not a major factor in determining DD susceptibility and suggest that contact with slurry could contribute to DD infection by increasing the permeability of the skin, which may facilitate pathogen entry. Further work is required to clarify the role played by slurry in the pathogenesis of DD.
One of the central results in Einstein’s theory of Brownian motion is that the mean
square displacement of a randomly moving Brownian particle scales linearly with time. Over
the past few decades sophisticated experiments and data collection in numerous biological,
physical and financial systems have revealed anomalous sub-diffusion in which the mean
square displacement grows slower than linearly with time. A major theoretical challenge
has been to derive the appropriate evolution equation for the probability density function
of sub-diffusion taking into account further complications from force fields and
reactions. Here we present a derivation of the generalised master equation for an ensemble
of particles undergoing reactions whilst being subject to an external force field. From
this general equation we show reductions to a range of well known special cases, including
the fractional reaction diffusion equation and the fractional Fokker-Planck equation.
A spontaneous cerebrospinal fluid leak can sometimes only become apparent following grommet insertion and usually represents dehiscence of the tegmen tympani, which is an uncommon condition.
This report aimed to reaffirm the importance of recognising this unusual presentation and outline management options.
A 63-year-old man with conductive hearing loss and type B (flat) tympanometry underwent grommet insertion into his left ear, which resulted in cerebrospinal fluid otorrhoea. A defect of the tegmen tympani was found. This was successfully repaired via a transmastoid approach using a multi-layered grafting technique.
Dehiscence of the tegmen tympani is uncommon and may only come to light following grommet insertion, which may be problematic for the uninformed otolaryngologist. Education is important to ensure early recognition and appropriate management.
To review our experience of cochlear implant failure and subsequent revision surgery, and to illustrate the experience we have gained by presenting a series of lessons learned.
A combined retrospective and prospective study of revision surgery in a UK regional cochlear implant centre.
Of the 746 cochlear implantations undertaken, 33 (4.7 per cent of adults and 4.1 per cent of children) had a registered failure requiring re-implantation. The mean time to device failure was 60 months in adults and 35 months in children. Causes of cochlear implant failure were medical (n = 11), electrode displacement (n = 2), ‘hard device failure’ (n = 15) and ‘soft device failure’ (n = 5). Chronic suppurative otitis media and post-auricular mastoid abscess were the commonest causes of medical failure. There was one case of electrode array displacement as a direct result of skin flap revision surgery. In 80 per cent of cases, audiological performances were stable or improved following re-implantation.
As the number of cochlear implants increase and patients outlive the lifespan of their devices, we will face a growing number of revision procedures. Audiologists and otologists should be competent in diagnosing and managing device failure and medical complications requiring cochlear re-implantation.
Long-term sediment and ground-penetrating radar data from Davis Pond, a small lake near the Hudson River valley, reveal past droughts in a historically humid region that presently supplies water to millions of people in and around New York City. A minimum of eleven sandy paleoshoreline deposits in the lake date from 13.4 to 0.6 cal ka BP. The deposits span 1500 to 200 yr between bracketing radiocarbon ages, and intrude into lacustrine silts up to 9.0 m below the modern lake surface in a transect of six sediment cores. Three low stands, ca. 13.4–10.9, 9.2 and 8.2 cal ka BP indicate low regional moisture balance when low temperatures affected the North Atlantic region. Consistent with insolation trends, water levels rose from ca. 8.0 cal ka BP to present, but five low stands interrupted the rise and are likely associated with ocean–atmosphere interactions. Similar to evidence from other studies, the data from Davis Pond indicate repeated multi-century periods of prolonged or frequent droughts super-imposed on long-term regional trends toward high water levels. The patterns indicate that water supplies in this heavily populated region have continuously varied at multiple time scales and confirm that humid regions such as the northeastern United States are more prone to severe drought than historically expected.
We evaluated use of the periodically rotated overlapping parallel lines with enhanced reconstruction diffusion-weighted imaging sequence, compared with conventional echo planar magnetic resonance imaging, in the detection of middle-ear cholesteatoma.
Material and methods:
Sixteen patients awaiting second-stage combined approach tympanoplasty and three patients awaiting first-stage combined approach tympanoplasty underwent magnetic resonance imaging with both (1) the periodically rotated overlapping parallel lines with enhanced reconstruction sequence (i.e. non echo planar imaging) and (2) the array spatial sensitivity encoding technique sequence (i.e. echo planar imaging). Two neuroradiologists independently evaluated the images produced by both sequences. Radiology findings were correlated with surgical findings.
Results and analysis:
Seven cholesteatomas were found at surgery. Neither of the assessed imaging sequences were able to detect cholesteatoma of less than 4 mm. Rates for sensitivity, specificity, and positive and negative predictive values are presented.
Decisions on whether or not to operate for cholesteatoma cannot be made based on the two imaging sequences assessed, as evaluated in this study. Other contributing factors are discussed, such as the radiological learning curve and technical limitations of the magnetic resonance imaging equipment.
To report a rare condition affecting the temporal bone. Immunoglobulin G4 related systemic sclerosing disease is a recently described autoimmune condition with manifestations typically involving the pancreas, biliary system, salivary glands, lungs, kidneys and prostate. Histologically, it is characterised by T-cell infiltration, fibrosis and numerous immunoglobulin G4-positive plasma cells. This condition previously fell under the umbrella diagnosis of inflammatory pseudotumour and inflammatory myofibroblastic tumour.
We present the case of a 58-year-old woman with multiple inflammatory masses involving the pharynx, gall bladder, lungs, pelvis, omentum, eyes and left temporal bone, over a seven-year period. We describe this patient's unusual clinical course and pathological features, which resulted in a change of diagnosis from metastatic inflammatory myofibroblastic tumour to immunoglobulin G4 related systemic sclerosing disease. We also review the literature regarding the management of inflammatory pseudotumours of the temporal bone, and how this differs from the management of immunoglobulin G4 related systemic sclerosing disease.
We would recommend a full review of all histological specimens in patients with a diagnosis of temporal bone inflammatory pseudotumour or inflammatory myofibroblastic tumour. Consideration should be given to immunohistochemical analysis for anaplastic lymphoma kinase and immunoglobulin G4, with measurement of serum levels of the latter. Management of the condition is medical, with corticosteroids and immunosuppression, rather than surgical excision.
Kinetic theory, including ion Larmor radius effects, is used to analyse the Alfvén wave heating of cylindrical plasmas using axisymmetric waves excited by an antenna at frequencies up to the ion cyclotron frequency. At the Alfvén resonance position, the compressional wave is mode converted to a quasi-electrostatic wave (QEW) which propagates towards the plasma centre or edge depending on whether the plasma is hot or warm. The energy absorbed by the plasma agrees with the MHD theory predictions provided the QEW is heavily damped before reaching the plasma centre or edge; if it is not, then QEW resonances may occur with a consequent increase in antenna resistance. The relation between ion cyclotron wave resonances and QEW resonances in a hot plasma is shown. The behaviour described above is demonstrated by numerical solution of the wave equations for small and large tokamak-like plasmas. WKB theory has been used to derive useful expressions which quantify the QEW behaviour.
The parametric decay of a magneto-acoustic pump wave into low-frequency waves modified by finite temperature effects is considered. The excited waves are the kinetic Alfvén wave and the ion-acoustic wave. The former wave plays an important role in linear heating schemes employing the mode conversion of magneto-acoustic waves at the Alfvén resonance. Here we calculate the parametric growth rates and pump thresholds for excitation of these waves. The main result is that finite temperature effects tend to reduce the growth rate of Alfvén waves.
MHD theory with the Hall term has been used to analyse the Alfvén resonance heating of cylindrical plasmas using axisymmetric waves excited by an antenna. An analytic expression for the antenna impedance has been derived for a simple plasma model and this is used to help interpret the computational results for small, medium and large plasmas. Compressional wave eigenmodes give large antenna resistances; however, the energy is deposited near the plasma surface. At a frequency just above each eigenfrequency, the Alfvén resonance damping is zero. Below the first eigenfrequency, the energy can be deposited near the plasma centre; however, the antenna resistance is fairly low except for medium size plasmas with a nearly constant central density. Ion cyclotron wave resonances are briefly discussed. Some general concepts relevant to the penetration of wave energy into large plasmas are presented.
Bony canalplasty is a common otological procedure performed to widen a narrow ear canal. The aim of this report is to describe two unusual patients who presented with a canal wall cholesteatoma many years after bony canalplasty.
Two patients, aged 28 and 52 years, are presented. Both underwent canalplasty, 14 and 17 years before re-presenting with cholesteatoma evident through posterior canal wall defects. Both patients underwent exploration of the mastoid cavities and cartilage reconstruction of the canal walls. There was no recurrence at 24 and three month follow-up examinations (variously), hearing was preserved in both cases, and the patients suffered no early complications.
The most frequent long-term complication of canalplasty is re-stenosis of the external auditory canal. The importance of sealing any inadvertently opened mastoid air cells, in order to avoid the late complication reported, is emphasised.
The aim of this study was to investigate the impact of cochlear implant electrode insertion on middle-ear low frequency function in humans.
Preservation of residual low frequency hearing with addition of electrical speech processing can improve the speech perception abilities and hearing in noise of cochlear implant users. Preservation of low frequency hearing requires an intact middle-ear conductive mechanism in addition to intact inner-ear mechanisms. Little is known about the effect of a cochlear implant electrode on middle-ear function.
Stapes displacement was measured in seven patients undergoing cochlear implantation. Measurements were carried out intra-operatively before and after electrode insertion. Each patient acted as his or her own control. Sound was delivered into the external auditory canal via a speaker and calibrated via a probe microphone. The speaker and probe microphone were integrated into an individually custom-made ear mould. Ossicular displacement in response to a multisine stimulus at 80 dB SPL was measured at the incudostapedial joint via the posterior tympanotomy, using an operating microscope mounted laser Doppler vibrometry system.
Insertion of a cochlear implant electrode into the scala tympani had a variable effect on stapes displacement. In three patients, there was little change in stapes displacement following electrode insertion. In two patients, there was a significant increase, while in a further two there was a significant reduction in stapes displacement. This variability may reflect alteration of cochlear impedance, possibly due to differing loss of perilymph associated with the electrode insertion.
Insertion of a cochlear implant electrode produces a change in stapes displacement at low frequencies, which may have an effect on residual low frequency hearing thresholds.
We present the first reported case of a middle-ear lipoma presenting with facial nerve palsy. We review the available literature on middle-ear lipomas and alert the surgeon to the possibility of a lipoma occurring in this location.
A 33-year-old man presented to our unit with a right-sided, House–Brackmann grade two, lower motor neurone facial palsy. A computed tomography scan revealed abnormal soft tissue in the epitympanic recess, extending to the region of the geniculate ganglion. At middle-ear exploration, a lump of fatty tissue was found filling the anterior middle-ear cleft, juxtaposed to the horizontal portion of the facial nerve. The patient's facial palsy resolved within a few weeks of surgery.
Lipomas are a rare but real differential diagnosis of a mass in the middle ear. Early imaging is advised.