Mapping the current flow in sacral nerve stimulation using computational modelling

© The Institution of Engineering and Technology 2019Sacral nerve stimulation (SNS) is an established treatment for faecal incontinence involving the implantation of a quadripolar electrode into a sacral foramen, through which an electrical stimulus is applied. Little is known about the induced spread of electric current around the SNS electrode and its effect on adjacent tissues, which limits optimisation of this treatment. The authors constructed a 3-dimensional imaging based finite element model in order to calculate and visualise the stimulation induced current and coupled this to biophysical models of nerve fibres. They investigated the impact of tissue inhomogeneity, electrode model choice and contact configuration and found a number of effects. (i) The presence of anatomical detail changes the estimate of stimulation effects in size and shape. (ii) The difference between the two models of electrodes is minimal for electrode contacts of the same length. (iii) Surprisingly, in this arrangement of electrode and neural fibre, monopolar and bipolar stimulation induce a similar effect. (iv) Interestingly when the active contact is larger, the volume of tissue activated reduces. This work establishes a protocol to better understand both therapeutic and adverse stimulation effects and in the future will enable patient-specific adjustments of stimulation parameters.Peer reviewe

Hearing what isn't said

No abstract available

Oncological and clinical outcomes after conventional right hemicolectomy

Purpose: Complete mesocolic excision (CME) has been proposed for better local control of colon cancer and to improve cancer-specific survival (CSS). However, CME may be associated with increased morbidity from bleeding during central vascular ligation. This study aimed to investigate the outcome of conventional right hemicolectomy, a traditional anatomical dissection along anatomical planes with radical excision of the central lymph nodes at the level of the origin of colic artery but without exposure of superior mesenteric vein and artery (SMV/SMA). Method: This was a retrospective review of a cohort of all elective right hemicolectomies performed at a specialist tertiary unit during a five-year period (2011–2015). Results: Five-hundred-nineteen patients (271 female, a median age of 73.0 years (interquartile range (IQR) 65.0–80.0)) were included (Stage I disease: 2.7%, stage II: 53.2%, stage III: 33.3%, stage IV: 10.8%). At the latest follow-up (a median 47 months (IQR 29–67)), local recurrence occurred in 34 patients (6.6%). Three-year overall survival was 74.4% and 3-year CSS was 85.9%. Subgroup analysis for stage I–III showed local recurrence in 6.0%, sole distant recurrence in 7.6% while 19 patients (4.1%) suffered concomitant local and distant recurrence. The anastomotic leak rate was 1.0% and perioperative bleeding occurred in 1.2%. Conclusions: Oncological outcomes comparable to those of CME can be achieved by conventional surgery but with low rates of bleeding complications and anastomotic leakage. The proposed advantages of CME should be carefully considered and balanced against patients’ co-morbidities and potential complications

Development of a customised data management system for a COVID-19-adapted colorectal cancer pathway

Objectives A customised data management system was required for a rapidly implemented COVID-19-adapted colorectal cancer pathway in order to mitigate the risks of delayed and missed diagnoses during the pandemic. We assessed its performance and robustness.Methods A system was developed using Microsoft Excel (2007) to retain the spreadsheets’ intuitiveness of direct data entry. Visual Basic for Applications (VBA) was used to construct a user-friendly interface to enhance efficiency of data entry and segregate the data for operational tasks.Results Large data segregation was possible using VBA macros. Data validation and conditional formatting minimised data entry errors. Computation by the COUNT function facilitated live data monitoring.Conclusion It is possible to rapidly implement a makeshift database system with clinicians’ regular input. Large-volume data management using a spreadsheet system is possible with appropriate data definition and VBA-programmed data segregation. The described concept is applicable to any data management system construction requiring speed and flexibility in a resource-limited situation

The ASTRO-H X-ray Observatory

The joint JAXA/NASA ASTRO-H mission is the sixth in a series of highly successful X-ray missions initiated by the Institute of Space and Astronautical Science (ISAS). ASTRO-H will investigate the physics of the high-energy universe via a suite of four instruments, covering a very wide energy range, from 0.3 keV to 600 keV. These instruments include a high-resolution, high-throughput spectrometer sensitive over 0.3-2 keV with high spectral resolution of Delta E < 7 eV, enabled by a micro-calorimeter array located in the focal plane of thin-foil X-ray optics; hard X-ray imaging spectrometers covering 5-80 keV, located in the focal plane of multilayer-coated, focusing hard X-ray mirrors; a wide-field imaging spectrometer sensitive over 0.4-12 keV, with an X-ray CCD camera in the focal plane of a soft X-ray telescope; and a non-focusing Compton-camera type soft gamma-ray detector, sensitive in the 40-600 keV band. The simultaneous broad bandpass, coupled with high spectral resolution, will enable the pursuit of a wide variety of important science themes.Comment: 22 pages, 17 figures, Proceedings of the SPIE Astronomical Instrumentation "Space Telescopes and Instrumentation 2012: Ultraviolet to Gamma Ray

Lack of collagen alpha 6(IV) chain in mice does not cause severe-to-profound hearing loss or cochlear malformation, a distinct phenotype from nonsyndromic hearing loss with COL4A6 missense mutation

Congenital hearing loss affects 1 in every 1000 births, with genetic mutations contributing to more than 50% of all cases. X-linked nonsyndromic hereditary hearing loss is associated with six loci (DFNX1-6) and five genes. Recently, the missense mutation (c.1771G>A, p.Gly591Ser) in COL4A6, encoding the basement membrane (BM) collagen alpha 6(IV) chain, was shown to be associated with X-linked congenital nonsyndromic hearing loss with cochlear malformation. However, the mechanism by which the COL4A6 mutation impacts hereditary hearing loss has not yet been elucidated. Herein, we investigated Col4a6 knockout (KO) effects on hearing function and cochlear formation in mice. Immunohistochemistry showed that the collagen alpha 6(IV) chain was distributed throughout the mouse cochlea within subepithelial BMs underlying the interdental cells, inner sulcus cells, basilar membrane, outer sulcus cells, root cells, Reissner's membrane, and perivascular BMs in the spiral limbus, spiral ligament, and stria vascularis. However, the click-evoked auditory brainstem response analysis did not show significant changes in the hearing threshold of Col4a6 KO mice compared with wild-type (WT) mice with the same genetic background. In addition, the cochlear structures of Col4a6 KO mice did not exhibit morphological alterations, according to the results of high-resolution micro-computed tomography and histology. Hence, loss of Col4a6 gene expression in mice showed normal click ABR thresholds and normal cochlear formation, which differs from humans with the COL4A6 missense mutation c.1771G>A, p.Gly591Ser. Therefore, the deleterious effects in the auditory system caused by the missense mutation in COL4A6 are likely due to the dominant-negative effects of the alpha 6(IV) chain and/or alpha 5 alpha 6 alpha 5(IV) heterotrimer with an aberrant structure that would not occur in cases with loss of gene expression

What Constitutes a High-Quality Guideline:Exploring Consumers' Views

Introduction: Clinical guidelines are a cornerstone of evidence-based medicine. Little is known about clinicians' knowledge of guideline development and how they perceive guideline quality. Methods:A survey protocol was designed according to the CHERRIES (improving the quality of web surveys: the Checklist for Reporting Results of Internet E-Surveys) checklist. The survey explored three main aspects: high-quality markers of guidelines, knowledge of guideline development, and areas for improvement. The survey was conducted by contacting UEG and affiliated societies by email and via social media. All valid answers to each question were counted. Results: A total of 585 participants responded during the 3-month period. Some 65.8% were aged between 30 and 60 years, and 75.4% were doctors. The most important perceived quality indicators within a guideline were ‘clear and actionable recommendations (97%)’, followed by ‘based on systematic literature review’ (96%), and ‘transparent methodology’ (90%). 230 (39.3%) respondents were previously involved in clinical guideline development. However, the experience of working with a methodologist (18.8%) and using well-established guideline checklists (AGREE-II [21.0%]), RIGHT (Reporting Items for Practice guidelines in HealThcare) (9.9%) were limited. Just under half of the responders (289, 49.4%) were familiar with the GRADE methodology. Apps (78.5%), webinars (73.8%), and short videos (68.2%) were popular tools to access clinical guidelines. Over 90% of responders stated that the reputation of the journal (92%) and the name of the society involved in guideline development (91%) were important. Two-thirds of the responders preferred to see abridged versions of guidelines and 69.2% preferred freely accessible or open access guidelines. Conclusion: Consumers are keen to read clear and actionable guidelines that are developed transparently. There is a gap in guideline development knowledge. Initiatives by medical journals and professional societies are important to ensure the development of accessible and robust clinical guidelines.<p/

Implementation of a risk mitigating COVID-adapted colorectal cancer pathway

No abstract available