The Sigma-trial protocol: a prospective double-blind multi-centre comparison of laparoscopic versus open elective sigmoid resection in patients with symptomatic diverticulitis

Backround  

Diverticulosis is a common disease in the western society with an incidence of 33–66%. 10–25% of these patients will develop diverticulitis. In order to prevent a high-risk acute operation it is advised to perform elective sigmoid resection after two episodes of diverticulitis in the elderly patient or after one episode in the younger (< 50 years) patient. Open sigmoid resection is still the gold standard, but laparoscopic colon resections seem to have certain advantages over open procedures. On the other hand, a double blind investigation has never been performed. The Sigma-trial is designed to evaluate the presumed advantages of laparoscopic over open sigmoid resections in patients with symptomatic diverticulitis.     

Improved lithium ion dynamics in crosslinked PMMA gel polymer electrolyte

Since PMMA-based gel polymer electrolytes could substitute PVDF-HFP based gels currently used in Li-ion batteries at lower financial and environmental costs, we investigate here the solvation and transport properties of the lithium ions in a crosslinked PMMA-based gel polymer electrolyte by a combination of thermal and electrochemical methods, Raman spectroscopy, pulse field gradient (PFG) and electrophoretic NMR (eNMR) techniques, as well as ab initio calculations. The conductivity of the gel containing 10 wt% polymer is only reduced by 14% relative to the liquid electrolyte. In addition, the co-solvation by polymer functional groups, a priori expected to slow lithium transport relatively to the anion, has instead a positive effect on lithium transport. Indeed, the ester groups not only participate in lithium solvation and increase ionic dissociation, but since this interaction is rather weak, rather than lowering the lithium diffusion relatively to other species, it mainly decorrelates lithium transport from anionic mobility. Compared to its liquid fraction, the gels show, at the same time, better dissociation and a higher lithium transference number, which results in a higher cationic conductivity, despite the overall conductivity loss.

Ionic transport was investigated in a PMMA gel electrolyte by electrochemical, Raman, PFG-NMR, e-NMR spectroscopies and ab initio calculations. The presence of the PMMA matrix reduces anionic mobility and decorrelates cationic and anionic transport.     

Language differences in qualitative research: is meaning lost in translation?

This article discusses challenges of language differences in qualitative research, when participants and the main researcher have the same non-English native language and the non-English data lead to an English publication. Challenges of translation are discussed from the perspective that interpretation of meaning is the core of qualitative research. As translation is also an interpretive act, meaning may get lost in the translation process. Recommendations are suggested, aiming to contribute to the best possible representation and understanding of the interpreted experiences of the participants and thereby to the validity of qualitative research.     

Measuring growth of residual cholesteatoma in subtotal petrosectomy

Background: Little is known about the growth rate of cholesteatoma in patients.

Objective: Investigate the growth of residual cholesteatoma in subtotal petrosectomy based on volume measured in MRI scans.

Materials and methods: Retrospective case series in a Tertiary Medical Centre. Thirteen residual cholesteatomas were identified in 10 patients after subtotal petrosectomy for which a wait-and-scan policy was adopted. Volume of the residual cholesteatoma was calculated by manual segmentation as well as the ‘box method’.

Results: Mean growth rate was 27.9 mm3/month (SD 22.8), with a large individual variation ranging from 2.2 to 69.8 mm3/month. No complications were reported in 10 patients with a wait-and-scan policy for residual cholesteatoma in subtotal petrosectomy. The box method overestimates growth rate compared to the reference method manual segmentation and a linear increase of this systematic error was seen with increasing size of the cholesteatoma.

Conclusions: Residual cholesteatoma growth rate shows a large individual variation. A wait-and-scan policy could be considered in case of a (small) residual in subtotal petrosectomy with ample room to grow before destroying any remaining structures. Furthermore, the clinically more applicable and less time-consuming box method can be used to accurately measure volumes of small cholesteatomasup to a volume of 500?mm³.     

Optische Kohärenztomographie in der Gynäkologie

Optical coherence tomography (OCT) is a new noninvasive technique that can be used to image tissue structures slice by slice with high resolution. Since its development in the early 1990s it has been used mainly as a diagnostic tool in ophthalmology for visualization of the posterior sections of the eye. OCT makes it possible to achieve high resolutions in cross-sectional imaging of superficial tissue structures. It is based on interferometry and can provide two-dimensional images with a high resolution of about 15 μm and a maximum detection depth of 2 mm with no need for contact. When it is used in combination with colposcopy noncontact imaging of the tissue below the surface of the cervix uteri is therefore possible.