Synthetic Elastography using B-mode Ultrasound through a Deep Fully-Convolutional Neural Network

Shear-wave elastography (SWE) permits local estimation of tissue elasticity, an important imaging marker in biomedicine. This recently-developed, advanced technique assesses the speed of a laterally-travelling shear wave after an acoustic radiation force "push" to estimate local Young's moduli in an operator-independent fashion. In this work, we show how synthetic SWE (sSWE) images can be generated based on conventional B-mode imaging through deep learning. Using side-by-side-view B-mode/SWE images collected in 50 patients with prostate cancer, we show that sSWE images with a pixel-wise mean absolute error of 4.5+/-0.96 kPa with regard to the original SWE can be generated. Visualization of high-level feature levels through t-Distributed Stochastic Neighbor Embedding reveals substantial overlap between data from two different scanners. Qualitatively, we examined the use of the sSWE methodology for B-mode images obtained with a scanner without SWE functionality. We also examined the use of this type of network in elasticity imaging in the thyroid. Limitations of the technique reside in the fact that networks have to be retrained for different organs, and that the method requires standardization of the imaging settings and procedure. Future research will be aimed at development of sSWE as an elasticity-related tissue typing strategy that is solely based on B-mode ultrasound acquisition, and the examination of its clinical utility.Comment: (c) 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other work

Adverse Effects of Carbetocin versus Oxytocin in the Prevention of Postpartum Haemorrhage after Caesarean Section: A Randomized Controlled Trial

Purpose. To compare the incidence of nausea, vomiting, and arterial hypotension between carbetocin and oxytocin to prevent haemorrhage after caesarean section (CS). Methods. A randomized controlled trial in term pregnant women undergoing planned CS. Groups were randomized to carbetocin or oxytocin. Blood pressure (BP), heart rate, presence of nausea/vomitus, and need for vasopressors were evaluated throughout surgery. Preoperative and postoperative haemoglobin and haematocrit levels were compared. Results. Fifty-eight women were randomized (carbetocin n=32; oxytocin n=26). Both medications had hypotensive effect, difference in BP for carbetocin versus oxytocin: systolic (14.4 ± 2.4 mmHg versus 8.5 ± 1.8 mmHg); diastolic (7.8 ± 1.6 mmHg versus 8.9 ± 3.0 mmHg) without significant difference between the drugs (p=0.1 and p=0.7). Both groups had similar needs for vasopressors. The presence of nausea was not rare, but the difference was not statistically significant (p=0.4). Average blood loss was slightly lower in the carbetocin group but not statistically significant (p=0.8). Conclusion. In planned CS, a possible clinical significant lower incidence of nausea after carbetocin was noted but this was not statistically significant. There were no differences regarding BP, heart rate, the need for vasopressor, and blood loss. The study was registered in the International Journal of Clinical Trials (ISRCTN 95504420, 2/2017)

Reversal of Hartmann's procedure through the stomal side: A new even more minimal invasive technique

Background: Several minimal invasive, mainly laparoscopic-assisted, techniques for reversal of Hartmann's procedure (HP) have been published. The purpose of this pilot study was to assess a minimal invasive procedure through the stomal site that may compare favorably with open or laparoscopic-assisted procedures in terms of operative time, hospital stay and postoperative complications. Methods: HP reversal through the stomal side was attempted in 13 consecutive patients. Lysis of intra-abdominal adhesions was done manually through an incision at the formal stoma side, without direct vision between thumb and index finger. The rectal stump was identified intra-abdominally using a transanal rigid club. A manually controlled stapled end-to-end colorectal anastomosis was created. Results: Mean duration of operation was 81 min (range 58-109 min); mean hospital stay was 4.2 days (range 2-7 days). In two patients the procedure was converted because of strong adhesions in the lower pelvic cavity around the rectal stump that could not be lysed manually safely. No complications occurred in the patients in whom reversal was completely done through the stomal site. Conclusions: In our opinion, restoration of intestinal continuity through the stomal side after HP is a feasible operation, without need for additional incisions. In the hands of a specialist gastrointestinal surgeon this technique can be attempted in all patients, as conversion to a laparoscopic-assisted or an open procedure can be performed when necessary

Quality of Life 1 Year After Laparoscopic Sleeve Gastrectomy Versus Laparoscopic Roux-en-Y Gastric Bypass: a Randomized Controlled Trial Focusing on Gastroesophageal Reflux Disease

Introduction: Bariatric surgery is the only treatment option that achieves sustained weight loss in obese patients and that also has positive effects on obesity-related comorbidities. Laparoscopic sleeve gastrectomy (LSG) seems to achieve equal weight loss as laparoscopic Roux-en-Y gastric bypass (LRYGB), but there is still much debate about the quality of life (QOL) after LSG, mainly concerning the association with gastroesophageal reflux. Our hypothesis is that QOL after LSG is comparable with QOL after LRYGB. Materials and Methods: Between February 2013 and February 2014, 150 patients were randomized to undergo either LSG or LRYGB in our clinic. Differences in QOL were compared between groups by using multiple QOL questionnaires at follow-up moments preoperatively and 2 and 12 months after surgery. Results: After 12 months of follow-up, 128 patients had returned the questionnaires. Most QOL questionnaires showed significant improvement in scores between the preoperative moment and after 12 months of follow-up. The Gastroesophageal Reflux Disease Questionnaire (GerdQ) score deteriorated in the LSG group after 2 months, but recovered again after 12 months. After 2 months of follow-up, the mean GerdQ score was 6.95 ± 2.14 in the LSG group versus 5.50 ± 1.49 in the LRYGB group (p < 0.001). After 1 year, the mean GerdQ score was 6.63 ± 2.26 in the LSG group and 5.60 ± 1.07 in the LRYGB group (p = 0.001). Conclusion: This randomized controlled trial shows that patients who underwent LSG have significantly higher GerdQ scores at both 2 and 12 months postoperatively than patients who underwent LRYGB, whereas overall QOL did not differ significantly

Population Pharmacokinetic Modelling of FE 999049, a Recombinant Human Follicle-Stimulating Hormone, in Healthy Women After Single Ascending Doses

OBJECTIVE: The purpose of this analysis was to develop a population pharmacokinetic model for a novel recombinant human follicle-stimulating hormone (FSH) (FE 999049) expressed from a human cell line of foetal retinal origin (PER.C6(®)) developed for controlled ovarian stimulation prior to assisted reproductive technologies.METHODS: Serum FSH levels were measured following a single subcutaneous FE 999049 injection of 37.5, 75, 150, 225 or 450 IU in 27 pituitary-suppressed healthy female subjects participating in this first-in-human single ascending dose trial. Data was analysed by nonlinear mixed effects population pharmacokinetic modelling in NONMEM 7.2.0.RESULTS: A one-compartment model with first-order absorption and elimination rates was found to best describe the data. A transit model was introduced to describe a delay in the absorption process. The apparent clearance (CL/F) and apparent volume of distribution (V/F) estimates were found to increase with body weight. Body weight was included as an allometrically scaled covariate with a power exponent of 0.75 for CL/F and 1 for V/F.CONCLUSIONS: The single-dose pharmacokinetics of FE 999049 were adequately described by a population pharmacokinetic model. The average drug concentration at steady state is expected to be reduced with increasing body weight

Laparoscopic sleeve gastrectomy with an extensive posterior mobilization: Technique and preliminary results

Background: Laparoscopic sleeve gastrectomy (LSG) is becoming increasingly popular as a stand-alone procedure for the treatment of morbidly obese patients. A direct posterior approach to the angle of His was developed at our department to improve visualization of the difficult dissection of the short gastric vessels and to facilitate proper mobilization of the stomach around the left crus enabling safe realization of a tight sleeve. The technique and its preliminary results are described. Methods: LSG by posterior approach was performed in a consecutive series of 445 (110 male/335 female, age 18-63 years, mean body mass index 46 kg/m2 (range 35-76)) patients between 2007 and 2010. Results: Weight loss defined as mean percent excess weight loss (%EWL) was 71% (±26%) at 1 year, 69% (±25%) at 2 years, and 55% (±27%) at 3 years. Sixteen patients (4%) developed postoperative intra-abdominal hematoma, 8 patients (2%) anastomotic leakage, and 6 patients intra-abdominal abscess (1%), requiring reoperation in 20 patients (4%). Five patients (1%) had pulmonary embolism. Thirty-day mortality rate was 0.2%. Conclusions: LSG by the posterior approach is a safe and effective procedure, enabling a tight sleeve formation leading to satisfactory %EWL results. Since long-term results of LSG are unknown, further studies are needed to define the exact place of the LSG as a stand-alone bariatric proc

The Influence of Scale Preferences on the Design of a Water Innovation: A Case in Dutch River Management

The debate on scale use in river management focuses primarily on the (lack of) fit between the bio-geophysical and institutional systems. However, in this article we focus on the ‘subjective’ aspect of scale preferences in water governance. We apply an adapted version of the Integrated Scale Hierarchy for Rivers to determine the degree of fit between the scale preferences of the actors involved in a Dutch case study and the scale requirements of the innovative river management concept. This allows us to understand which riverine processes and characteristics are regarded as important by the different actors and to identify mismatches in scale perspectives as they manifest themselves in water management practice. We discover that inflexibility in scale use on the part of the involved actors places bounds on the design and quality of interventions and demonstrate that a more flexible use of scales in the design phase of a river management intervention has the potential to lead to more effective solutions