Breast cancer risk in mothers of twins.

The risk of breast cancer associated with delivering a twin birth was examined in a population-based nested case-control study of nearly 4800 Swedish women with breast cancer and 47000 age-matched control subjects. All were aged less than 50 years and parous. After adjustment for age at first birth and parity, a 29% reduction in breast cancer risk was observed in mothers of twins relative to those who were not (odds ratio = 0.71, 95% confidence interval 0.55-0.91). These results provide evidence that women who bear twins are at reduced risk of breast cancer, one explanation for which may be their unusual levels of hormonal exposure

Depth-Supervised NeRF for Multi-View RGB-D Operating Room Images

Neural Radiance Fields (NeRF) is a powerful novel technology for the reconstruction of 3D scenes from a set of images captured by static cameras. Renders of these reconstructions could play a role in virtual presence in the operating room (OR), e.g. for training purposes. In contrast to existing systems for virtual presence, NeRF can provide real instead of simulated surgeries. This work shows how NeRF can be used for view synthesis in the OR. A depth-supervised NeRF (DS-NeRF) is trained with three or five synchronised cameras that capture the surgical field in knee replacement surgery videos from the 4D-OR dataset. The algorithm is trained and evaluated for images in five distinct phases before and during the surgery. With qualitative analysis, we inspect views synthesised by a virtual camera that moves in 180 degrees around the surgical field. Additionally, we quantitatively inspect view synthesis from an unseen camera position in terms of PSNR, SSIM and LPIPS for the colour channels and in terms of MAE and error percentage for the estimated depth. DS-NeRF generates geometrically consistent views, also from interpolated camera positions. Views are generated from an unseen camera pose with an average PSNR of 17.8 and a depth estimation error of 2.10%. However, due to artefacts and missing of fine details, the synthesised views do not look photo-realistic. Our results show the potential of NeRF for view synthesis in the OR. Recent developments, such as NeRF for video synthesis and training speedups, require further exploration to reveal its full potential.Comment: 12 pages, 4 figures, submitted to the 14th International Conference on Information Processing in Computer-Assisted Intervention

Ninety-day morbidity of robot-assisted redo surgery for recurrent rectal prolapse, mesh erosion and pelvic pain:lessons learned from 9 years' experience in a tertiary referral centre

Aim With increasing follow-up of patients treated with minimally invasive ventral mesh rectopexy (VMR) more redo surgery can be expected for recurrent rectal prolapse, mesh erosion and pelvic pain. The aim of this study is to evaluate the 90-day morbidity of robot-assisted redo interventions. Method All robot-assisted redo interventions after primary transabdominal repair of rectal prolapse between 2011 and 2019 were retrospectively analysed and compared with the results for patients after primary robot-assisted VMR during the same period. The redo interventions were divided into groups based on the indication for surgery (recurrent prolapse, mesh erosion, pelvic pain). Intraoperative complications and 90-day postoperative morbidity were evaluated. Results Three hundred and fifty nine patients were treated with primary VMR, with 73 for recurrent rectal prolapse, 12 for mesh erosion and 14 for pelvic pain. Complications of recurrent prolapse surgeries were comparable to those of primary VMR (p > 0.05). More intraoperative complications, minor and major complications were seen in redo surgery for erosion compared with primary VMR (23% vs. 3%, p = 0.01; 31% vs. 11%, p = 0.055; and 38% vs. 1%, p 0.05). Half of the patients with pelvic pain experienced relief of their symptoms. Conclusion Redo surgery for management of recurrent rectal prolapse is safe. Redo surgery for mesh erosion is associated with high morbidity rates. Redo surgery for pelvic pain can have major complications and is only effective in half of the cases

From Da Vinci Si to Da Vinci Xi:realistic times in draping and docking the robot

Robot-assisted surgery is assumed to be time consuming partially due to extra time needed in preparing the robot. The objective of this study was to give realistic times in Da Vinci Xi draping and docking and to analyse the learning curve in the transition from the Si to the Xi in an experienced team. This prospective study was held in a hospital with a high volume of robot-assisted surgery in general surgery, urology and gynaecology. Times from the moment patients entered the operating room until the surgeon took place behind console were precisely recorded during the first 6 weeks after the implementation of the Xi. In total, 65 procedures were performed and documented. The learning curve for the process of draping and docking the robot was reached after 21 and 18 cases, respectively. Mean times after completion of the learning curve were 5 min for draping and 7 min for docking and were statistically different from mean times before completion of the learning curve (p values <0.01). In dedicated teams netto extra time needed for preparing the Xi can even be reduced to just the time needed for docking. Thus, setting up the robot should have limited impact on overall time spent in the operation room

Intestinal motility distal of a deviating ileostomy after rectal resection with the construction of a primary anastomosis:results of the prospective COLO-MOVE study

Purpose No consensus exists regarding the use of preoperative bowel preparation for patients undergoing a low anterior resection (LAR). Several comparative studies show similar outcomes when a single time enema (STE) is compared with mechanical bowel preparation (MBP). It is hypothesized that STE is comparable with MBP due to a decrease in intestinal motility distal of a newly constructed diverting ileostomy (DI). Methods In this prospective single-centre cohort study, patients undergoing a LAR with primary anastomosis and DI construction were given a STE 2 h pre-operatively. Radio-opaque markers were inserted in the efferent loop of the DI during surgery, and plain abdominal X-rays were made during the first, third, fifth and seventh postoperative day to visualize intestinal motility. Results Thirty-nine patients were included. Radio-opaque markers were situated in the ileum or right colon in 100%, 100% and 97.1% of the patients during respectively the first, third and fifth postoperative day. One patient had its most distal marker situated in the left colon during day five. In none of the patients, the markers were seen distal of the anastomosis. Conclusion Intestinal motility distally of the DI is decreased in patients who undergo a LAR resection with the construction of an anastomosis and DI, while preoperatively receiving a STE

Surgical Reintervention After Failed Antireflux Surgery: A Systematic Review of the Literature

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Consequences of digital mammography in population-based breast cancer screening: initial changes and long-term impact on referral rates

Contains fulltext : 89208.pdf (publisher's version ) (Closed access)OBJECTIVES: To investigate the referral pattern after the transition to full-field digital mammography (FFDM) in a population-based breast cancer screening programme. METHODS: Preceding the nationwide digitalisation of the Dutch screening programme, an FFDM feasibility study was conducted. Detection and referral rates for FFDM and screen-film mammography (SFM) were compared for first and subsequent screens. Furthermore, radiological characteristics of referrals in digital screening were assessed. RESULTS: A total of 312,414 screening mammograms were performed (43,913 digital and 268,501 conventional), with 4,473 consecutive referrals (966 following FFDM). Initially the FFDM referral rate peaked, and many false-positive results were noted as a consequence of pseudolesions and increased detection of (benign) microcalcifications. A higher overall referral rate was observed in FFDM screening in both first and subsequent examinations (p < .001), with a significant increase in cancer detection (p = .010). CONCLUSION: As a result of initial inexperience with digital screening images implementing FFDM in a population-based breast cancer screening programme may lead to a strong, but temporary increase in referral. Dedicated training in digital screening for radiographers and screening radiologists is therefore recommended. Referral rates decrease and stabilise (learning curve effect) at a higher level than in conventional screening, yet with significantly enhanced cancer detection.1 september 201

Virtual reality training for endoscopic surgery: voluntary or obligatory?

INTRODUCTION: Virtual reality (VR) simulators have been developed to train basic endoscopic surgical skills outside of the operating room. An important issue is how to create optimal conditions for integration of these types of simulators into the surgical training curriculum. The willingness of surgical residents to train these skills on a voluntary basis was surveyed. METHODS: Twenty-one surgical residents were given unrestricted access to a VR simulator for a period of four months. After this period, a competitive element was introduced to enhance individual training time spent on the simulator. The overall end-scores for individual residents were announced periodically to the full surgical department, and the winner was awarded a prize. RESULTS: In the first four months of study, only two of the 21 residents (10%) trained on the simulator, for a total time span of 163 minutes. After introducing the competitive element the number of trainees increased to seven residents (33%). The amount of training time spent on the simulator increased to 738 minutes. CONCLUSIONS: Free unlimited access to a VR simulator for training basic endoscopic skills, without any form of obligation or assessment, did not motivate surgical residents to use the simulator. Introducing a competitive element for enhancing training time had only a marginal effect. The acquisition of expensive devices to train basic psychomotor skills for endoscopic surgery is probably only effective when it is an integrated and mandatory part of the surgical curriculu

Sustainability of participation in collective pension schemes: An option pricing approach

This paper contributes to the discussion about mandatory participation in collective funded pension schemes. It explores under what circumstances individual participants exercise the option to exit such a scheme if participation is voluntary. We begin by showing how the willingness to participate increases if the period over which the option is valid becomes longer. Then, we demonstrate how the pension fund’s set of policy instruments can be deployed to minimize the likelihood that any cohort exits the pension scheme. The instruments consist of contribution and indexation policies. Recovery of the funding ratio, i.e. The ratio of assets over liabilities, to its regulatory target level may be based on uniform contributions or age-dependent contributions. Specifically, while the value of the exit option deters younger workers from exiting the pension fund, a uniform contribution policy encourages older workers to stay in the pension scheme

Long-term Anatomical and Functional Results of Robot-Assisted Pelvic Floor Surgery for the Management of Multicompartment Prolapse:A Prospective Study

BACKGROUND: Long-term data on robot-assisted sacrocolporectopexy for the treatment of multicompartment pelvic organ prolapse are scarce. With the rising prevalence of prolapse and increasing surgical repair, it is essential to evaluate long-term results. OBJECTIVE: This study aimed to evaluate long-term functional and anatomic outcomes after sacrocolporectopexy. DESIGN: This is a prospective, observational cohort study. SETTINGS: This study was conducted at a teaching hospital with tertiary referral function for patients with gynecological/rectal prolapse. PATIENTS: All patients undergoing robot-assisted sacrocolporectopexy from 2011 to 2012 were included. INTERVENTION: Robot-assisted sacrocolporectopexy was performed. MAIN OUTCOME MEASURES: The primary outcome was the anatomic cure rate after 1 and 4 years, defined as simplified pelvic organ prolapse quantification stage 1 vaginal apical prolapse and no external rectal prolapse or internal rectal prolapse present. Kaplan-Meier curves were used for determination of recurrence-free intervals. Secondary outcomes were functional pelvic floor symptoms (symptoms of bulge, obstructed defecation, fecal incontinence, urogenital distress inventory) and quality of life (Pelvic Floor Impact Questionnaire). RESULTS: Fifty-three patients were included. After 12 and 48 months, the recurrence-free intervals based on Kaplan-Meier estimates were 100% and 90%. In total, there were 10 recurrences: 2 apical and 8 internal rectal prolapses. Symptoms of bulge (94%-12%; p < 0.0005), fecal incontinence (62%-32%; p < 0.0005), obstructed defecation (59%-24%; p = 0.008), and median Pelvic Floor Impact Questionnaire scores (124-5; p = 0.022) improved significantly at final follow-up. Median urogenital distress inventory scores showed improvement after 1 year (30-13; p = 0.021). LIMITATIONS: This was an observational, single-center study with selective postoperative imaging. CONCLUSIONS: Ninety percent of patients were recurrence free 48 months after robot-assisted sacrocolporectopexy. Symptoms of vaginal bulge, quality of life, constipation, and fecal incontinence improved significantly. However, a subgroup of patients showed persistent bowel complaints that underlie the complexity of multicompartment prolapse. See Video Abstract at http://links.lww.com/DCR/B265