Management of epistaxis in hereditary haemorrhagic telangiectasia (HHT) patients using pulsed dye laser and the effect of withholding treatment during the COVID pandemic.

Using a patient survey, pulsed dye laser (PDL) treatment of epistaxis for hereditary haemorrhagic telangiectasia (HHT) patients was evaluated after initial referral. Subsequently, due to the COVID pandemic, a natural experimental set-up allowed assessment of an enforced withdrawal of treatment. A total of 34 subjects were identified as undergoing PDL for HHT-related epistaxis. They were surveyed to look at the effectiveness of PDL treatment after initial referral and at the effect of delay to treatment during COVID on epistaxis and the associated quality of life. The survey also examined the comparison to other available treatments. Retrospective pre-COVID Epistaxis Severity Scores (ESS) were compared to post-COVID data to assess the effect of treatment withdrawal. The patients were then followed up after resumption of their treatment to assess the ensuing change in ESS. After initial referral, frequency and severity of epistaxis decreased. Fifty-six percent of patients experienced several bleeds per day before treatment, compared to 12% after. 88% of patients had episodes of epistaxis longer than 5 min, which was halved to 44% after treatment. Average ESS pre-COVID was 4.42 compared to 5.43 post-COVID delay, with a significant statistical difference (p = 0.02). On resumption of treatment, average ESS reduced to below pre-COVID levels at 4.39 after only 2 sessions. Seventy-six percent of patients found that withdrawal of PDL during COVID diminished their quality of life. PDL treatment of nasal mucosal telangiectasia reduces the frequency and duration of epistaxis. The ESS is reduced following treatment with PDL and quality of life subjectively improved.

Early Laser for Burn Scars (ELABS): protocol for a multi-centre randomised, controlled trial of both the effectiveness and cost-effectiveness of the treatment of hypertrophic burn scars with Pulsed Dye Laser and standard care compared to standard care alone [version 1; peer review: 2 approved].

This paper outlines the protocol for a study that is being carried out at multiple centres across the UK in the next three years. It is a Research for Patient Benefit (RfPB) study funded by the National Institute for Healthcare Research (NIHR). The aim is to assess the effectiveness of treating hypertrophic burns scars with pulsed dye laser (PDL) at an early stage of scar formation. The objective is to improve Quality of Life for the patient by improving both the appearance and quality of burn scarring, as well as reducing its psychological impact. This is a parallel-arm randomised, controlled trial to compare PDL and standard care against standard care alone. The difference is measured between baseline and six-month follow-up. Recruits are within three months of healing from a burn injury; with wounds showing a defined potential for hypertrophic scarring. A total of 120 patients are recruited in a multi-centre study; with randomisation in a 1:1 allocation to each arm. The treatment arm receives 3 PDL treatments at six-week intervals in addition to standard care, whereas the control arm receives standard care alone. The primary outcome is the patient-rated part of the Patient and Observer Scar Scale (POSAS). Psychological and psycho-social impact is evaluated using the CARe burn scale (UWE, Bristol) and Quality Adjusted Life Years (QALY) is determined using the Short-Form Health Survey (SF-12). The study evaluates both the cost-effectiveness through an economic analysis and the patient-reported experience of the treatment by phone interviews.

Clinical decision making in the provision of audiovisual care for upper limb trauma: a survey of UK experiences.

Introduction: For many patients, audio-visual appointments have provided a timely and efficient way of seeking advice, assessment and treatment for their hand injuries during the NHS response to COVID-19. This study aimed to explore the experience of hand units across the UK in determining the safe and judicious use of audio-visual outpatient care for the management of acute upper limb trauma. Methods: An online cross-sectional survey was sent to the therapy leads of hand units across the UK. Questions focused on the experience of using audio-visual technology in the management of upper limb trauma, and the relevant factors in determining its appropriate use. A deductive mixed methods analysis was used to identify both common themes and capture community experience and characteristics. Results: A total of 51 out of 76 hand therapy units completed the survey; a response rate of 67%. Of these, 82% (42/51) reported using audio-visual technology to manage upper limb trauma during the UK COVID-19 lockdown. When determining patient suitability for audio-visual consultations, 73% (37/51) of respondents reported the use of COVID-19 guidelines, but only 35% (18/51) reported the use of a clinical decision-making tool. In agreement with our experience at Salisbury Hospital Foundation Trust, 92% (47/51) had concerns relating to the use of audio-visual care. Conclusion: The choice of safely managed remote care or in-person consultation has, to date, largely relied on the discretion of the clinician. A carefully designed clinical decision-making tool for the management of upper limb trauma is needed for use both in clinical practice and in future service planning.

A case report on the use of vibration to improve soft tissue extensibility after major trauma.

This report presents a case where vibration training to the arm alone, as opposed to whole-body vibration, was used to aid rehabilitation to a serious traumatic injury. An improvement in soft tissue extensibility to a major traumatic wound to the wrist and forearm has been noted in a therapy plan including vibration under stretch. After 12 weeks of intensive therapy, a considerable improvement was seen in both the active extension of the wrist and the composite extension of all fingers. This may highlight the use of vibration, as an adjunct to therapy, to specific areas of the human body for improving outcome from traumatic injury. LEVEL OF EVIDENCE: IV.

Model validation for a noninvasive arterial stenosis detection problem.

A current thrust in medical research is the development of a non-invasive method for detection, localization, and characterization of an arterial stenosis (a blockage or partial blockage in an artery). A method has been proposed to detect shear waves in the chest cavity which have been generated by disturbances in the blood flow resulting from a stenosis. In order to develop this methodology further, we use one-dimensional shear wave experimental data from novel acoustic phantoms to validate a corresponding viscoelastic mathematical model. We estimate model parameters which give a good fit (in a sense to be precisely defined) to the experimental data, and use asymptotic error theory to provide confidence intervals for parameter estimates. Finally, since a robust error model is necessary for accurate parameter estimates and confidence analysis, we include a comparison of absolute and relative models for measurement error.

High-order space-time finite element schemes for acoustic and viscodynamic wave equations with temporal decoupling.

We revisit a method originally introduced by Werder et al. (in Comput. Methods Appl. Mech. Engrg., 190:6685-6708, 2001) for temporally discontinuous Galerkin FEMs applied to a parabolic partial differential equation. In that approach, block systems arise because of the coupling of the spatial systems through inner products of the temporal basis functions. If the spatial finite element space is of dimension D and polynomials of degree r are used in time, the block system has dimension (r + 1)D and is usually regarded as being too large when r > 1. Werder et al. found that the space-time coupling matrices are diagonalizable over [Formula: see text] for r ⩽100, and this means that the time-coupled computations within a time step can actually be decoupled. By using either continuous Galerkin or spectral element methods in space, we apply this DG-in-time methodology, for the first time, to second-order wave equations including elastodynamics with and without Kelvin-Voigt and Maxwell-Zener viscoelasticity. An example set of numerical results is given to demonstrate the favourable effect on error and computational work of the moderately high-order (up to degree 7) temporal and spatio-temporal approximations, and we also touch on an application of this method to an ambitious problem related to the diagnosis of coronary artery disease. Copyright © 2014 The Authors. International Journal for Numerical Methods in Engineering published by John Wiley & Sons Ltd.

The speed of sound and attenuation of an IEC agar-based tissue-mimicking material for high frequency ultrasound applications.

This study characterized the acoustic properties of an International Electromechanical Commission (IEC) agar-based tissue mimicking material (TMM) at ultrasound frequencies in the range 10-47 MHz. A broadband reflection substitution technique was employed using two independent systems at 21°C ± 1°C. Using a commercially available preclinical ultrasound scanner and a scanning acoustic macroscope, the measured speeds of sound were 1547.4 ± 1.4 m∙s(-1) and 1548.0 ± 6.1 m∙s(-1), respectively, and were approximately constant over the frequency range. The measured attenuation (dB∙cm(-1)) was found to vary with frequency f (MHz) as 0.40f + 0.0076f(2). Using this polynomial equation and extrapolating to lower frequencies give values comparable to those published at lower frequencies and can estimate the attenuation of this TMM in the frequency range up to 47 MHz. This characterisation enhances understanding in the use of this TMM as a tissue equivalent material for high frequency ultrasound applications.

Sensitivity of loading to the timing of joint kinematic strategies in simulated forefoot impact landings.

The impact loads experienced in landing may be influenced by the joint kinematic strategy used. This study aimed to enhance the understanding of the sensitivity of impact loading to the timing of joint kinematic strategies in simulated forefoot landings. Coordinate and force data of drop landings were used to initiate, drive, and evaluate a wobbling mass model. Ankle, knee, and hip joint angle profile timings were modified in the simulated motions. Changes to the timing of the ankle and knee joint angle profiles were associated with substantial changes in the peak vertical ground reaction force (GFzmax) of up to 3.9 bodyweights (BW) and 1.5 BW, respectively, whereas loading was less sensitive to temporal changes in the hip joint strategy. Accentuated impact loads incurred by a modified knee flexion action may be explained by the need to maintain an ordered and controlled load attenuation strategy. Individual strategies and external and joint reaction forces should be considered for developing insight into loading in impact landings.

Assessment of tissue Doppler imaging measurements of arterial wall motion using a tissue mimicking test rig.

The aim of this in vitro study is to assess the accuracy of the tissue Doppler imaging arterial wall motion (TDI AWM) technique in measuring dilation over a range of distances and velocities. A test rig, consisting of two parallel blocks of tissue mimicking material (TMM), has been developed to generate known wall motion. One block remains stationary while the other moves in a cyclical motion. A calibrated laser range finder was used to measure the TMM motion. The TDI AWM measurements were found to underestimate the dilation by 21% +/- 4.7% when using the recommended scanner parameters. The size of the error was found to increase with a decrease in ultrasound output power. Results suggested that errors in the TDI AWM dilation measurements relate to underestimates in the velocity measured by the TDI technique. The error demonstrated in this study indicates a limitation in the value of TDI AWM result obtained in vivo. (E-mail: abigail.thrush@bartsandthelondon.nhs.uk).

Soft tissue contributions to impact forces simulated using a four-segment wobbling mass model of forefoot-heel landings.

The purpose of this investigation was to develop and evaluate a wobbling mass model of a female performing a drop landing and to examine the influence of soft tissue properties on the impact loads experienced. A planar model comprising a foot, shank, thigh and upper body segment was developed. Spring-damper systems coupled the foot to the ground and the wobbling masses to the rigid masses. Unlike traditional wobbling mass models of landing, the model included a foot segment, which allowed replication of forefoot-heel landing techniques and also used subject and movement-specific properties to simulate the landings. Kinematics and force data collected for three drop landings (height 0.46 m) performed by a female were separately used to drive and evaluate the model. The wobbling mass model successfully reproduced the measured force profiles to 9% (RMS differences) of the measured range and replicated the measured peak vertical ground reaction forces to 6%. The accuracies of the wobbling mass model and a corresponding rigid mass model were compared. The inclusion of soft tissue properties in the model contributed up to an 8.6 bodyweights reduction in peak impact loading and produced a 52% more accurate replication of the measured force profiles. The prominent role soft tissues have in load attenuation and the benefits of modelling soft tissue in simulations of landings were therefore highlighted. The success of the wobbling mass model in replicating the kinetics of actual landing performances suggests the model may be used in the future to gain a realistic insight into load attenuation strategies used by females.

Optimised performance of the backward longswing on rings.

Many elite gymnasts perform the straight arm backward longswing on rings in competition. Since points are deducted if gymnasts possess motion on completion of the movement, the ability to successfully perform the longswing to a stationary final handstand is of great importance. Sprigings et al. (1998) found that for a longswing initiated from a still handstand the optimum performance of an inelastic planar simulation model resulted in a residual swing of more than 3 degrees in the final handstand. For the present study, a three-dimensional simulation model of a gymnast swinging on rings, incorporating lateral arm movements used by gymnasts and mandatory apparatus elasticity, was used to investigate the possibility of performing a backward longswing initiated and completed in handstands with minimal swing. Root mean square differences between the actual and simulated performances for the orientations of the gymnast and rings cables, the combined cable tension and the extension of the gymnast were 3.2 degrees, 1.0 degrees, 270N and 0.05m respectively. The optimised simulated performance initiated from a handstand with 2.1 degrees of swing and using realistic changes to the gymnast's technique resulted in 0.6 degrees of residual swing in the final handstand. The sensitivity of the backward longswing to perturbations in the technique used for the optimised performance was determined. For a final handstand with minimal residual swing (2 degrees) the changes in body configuration must be timed to within 15 ms while a delay of 30 ms will result in considerable residual swing (7 degrees).