Metabolic outcomes in obese mice undergoing one-anastomosis gastric bypass (OAGB) with a long or a short biliopancreatic limb.

One-anastomosis gastric bypass (OAGB) has gained importance as a simple, safe, and effective operation to treat morbid obesity. We previously found that Roux-en-Y gastric bypass surgery with a long compared with a short biliopancreatic limb (BPL) leads to improved weight loss and glucose tolerance in obese mice. However, it is not known whether a long BPL in OAGB surgery also results in beneficial metabolic outcomes. Five-week-old male C57BL/6J mice fed a high-fat diet (HFD) for 8 weeks underwent OAGB surgery with defined BPL lengths (5.5 cm distally of the duodenojejunal junction for short and 9.5 cm for long BPL), or sham surgery combined with caloric restriction. Weight loss, glucose tolerance, obesity-related comorbidities, endocrine effects, gut microbiota, and bile acids were assessed. Total weight loss was independent of the length of the BPL after OAGB surgery. However, a long BPL was associated with lower glucose-stimulated insulin on day 14, and an improved glucose tolerance on day 35 after surgery. Moreover, a long BPL resulted in reduced total cholesterol, while there were no differences in the resolution of metabolic dysfunction-associated steatotic liver disease (MASLD) and adipose tissue inflammation. Tendencies of an attenuated hypothalamic-pituitary-adrenal (HPA) axis and aldosterone were present in the long BPL group. With both the short and long BPL, we found an increase in primary conjugated bile acids (pronounced in long BPL) along with a loss in bacterial Desulfovibrionaceae and Erysipelotrichaceae and simultaneous increase in Akkermansiaceae, Sutterellaceae, and Enterobacteriaceae. In summary, OAGB surgery with a long compared with a short BPL led to similar weight loss, but improved glucose metabolism, lipid, and endocrine outcomes in obese mice, potentially mediated through changes in gut microbiota and related bile acids. Tailoring the BPL length in humans might help to optimize metabolic outcomes after bariatric surgery.NEW & NOTEWORTHY Weight loss following OAGB surgery in obese mice was not influenced by BPL length, but a longer BPL was associated with improved metabolic outcomes, including glucose and lipid homeostasis. These changes could be mediated by bile acids upon altered gut microbiota. Further validation of these findings is required through a randomized human study.

Laparoscopic Roux-Y-gastric bypass versus laparoscopic one-anastomosis gastric bypass for obesity: clinical & metabolic results of a prospective randomized controlled trial.

BACKGROUND: One anastomosis gastric bypass (OAGB) has been proposed as an effective alternative to the current standard procedure in Switzerland, Roux-en-Y gastric bypass (RYGB). Prospective data comparing both procedures are scarce. Therefore, we performed a non-inferiority randomized controlled trial assessing the effectiveness and safety of these 2 operative techniques. METHOD: Eighty patients were randomized 1:1. OAGB consisted of a very long gastric pouch with a 200 cm biliopancreatic limb, RYGB of a 150 cm ante-colic alimentary and a 60 cm biliopancreatic limb, respectively. Primary endpoint was the percent excess weight loss (%EWL) at 12 months after surgery. RESULTS: Mean %EWL at 12 months was 87.9% (SD24.4) in the RYGB group and 104.1% (SD24.6) in the OAGB group (p = 0.006). There was no mortality. The rate of marginal ulcers was higher in patients with OAGB compared to those with RYGB (p = 0.011), while the total number of late complications did not statistically differ between the two groups. Except for the remission of GERD, which was higher in the RYGB group compared to OAGB, there was no difference between the groups regarding the remission of comorbidities. OAGB showed improved glucose control compared to the RYGB after 1 year (p = 0.001). Furthermore, glucagon-like peptide-1 increase was significantly higher in OAGB at 6 weeks (p = 0.041) and 1 year after surgery (p = 0.029). Quality of life improved after both surgeries, without differences between the groups. CONCLUSIONS: %EWL 1 year after surgery was higher in OAGB than in RYGB. A better glycemic control with a higher increase in GLP-1 was observed after OAGB compared to RYGB. TRIAL REGISTRATION: This trial is registered on ClinicalTrials.gov under the identifier NCT02601092.

Sex-specific differences in metabolic outcomes after sleeve gastrectomy and intermittent fasting in obese middle-aged mice.

Despite the high prevalence of obesity among middle-aged subjects, it is unclear if sex differences in middle age affect the metabolic outcomes of obesity therapies. Accordingly, in this study, middle-aged obese female and male mice were randomized to one of three groups: sleeve gastrectomy (SG), sham surgery ad libitum (SH-AL), or sham surgery with weight matching to SG through intermittent fasting with calorie restriction (SH-IF). Comprehensive measures of energy and glucose homeostasis, including energy intake, body weight, energy expenditure, glucose and insulin tolerance, and interscapular brown adipose tissue (iBAT) sympathetic innervation density were obtained. At the end of 8 wk, SG and SH-IF females had better metabolic outcomes than their male counterparts. SG females had improved weight loss maintenance, preservation of fat-free mass (FFM), higher total energy expenditure (TEE), normal locomotor activity, and reduced plasma insulin and white adipose tissue (WAT) inflammatory markers. SH-IF females also had lower plasma insulin and WAT inflammatory markers, and higher TEE than SH-IF males, despite their lower FFM. In addition, SH-IF females had higher iBAT sympathetic nerve density than SG and SH-AL females, whereas there were no differences among males. Notably, SH-IF mice of both sexes had the most improved glucose tolerance, highlighting the benefits of fasting, irrespective of weight loss. Results from this study demonstrate that in middle-aged obese mice, female sex is associated with better metabolic outcomes after SG or IF with calorie restriction. Clinical studies are needed to determine if sex differences should guide the choice of obesity therapies.NEW & NOTEWORTHY SG or IF with calorie restriction produces better metabolic outcomes in females than in males. IF with calorie restriction prevents metabolic adaptation, even in the face of fat-free mass loss. IF with calorie restriction in females only, is associated with increased iBAT sympathetic innervation, which possibly mitigates reductions in energy expenditure secondary to fat-free mass loss. Lastly, IF leads to better glucose homeostasis than SG, irrespective of sex.

Defining Global Benchmarks in Elective Secondary Bariatric Surgery Comprising Conversional, Revisional, and Reversal Procedures.

OBJECTIVE: To define "best possible" outcomes for secondary bariatric surgery (BS). BACKGROUND: Management of poor response and of long-term complications after BS is complex and under-investigated. Indications and types of reoperations vary widely and postoperative complication rates are higher compared to primary BS. METHODS: Out of 44,884 BS performed in 18 high-volume centers from 4 continents between 06/2013-05/2019, 5,349 (12%) secondary BS cases were identified. Twenty-one outcome benchmarks were established in low-risk patients, defined as the 75th percentile of the median outcome values of centers. Benchmark cases had no previous laparotomy, diabetes, sleep apnea, cardiopathy, renal insufficiency, inflammatory bowel disease, immunosuppression, thromboembolic events, BMI> 50 kg/m2 or age> 65 years. RESULTS: The benchmark cohort included 3143 cases, mainly females (85%), aged 43.8 ±â€Š10 years, 8.4 ±â€Š5.3 years after primary BS, with a BMI 35.2 ±â€Š7 kg/m2. Main indications were insufficient weight loss (43%) and gastro-esophageal reflux disease/dysphagia (25%). 90-days postoperatively, 14.6% of benchmark patients presented ≥1 complication, mortality was 0.06% (n = 2). Significantly higher morbidity was observed in non-benchmark cases (OR 1.37) and after conversional/reversal or revisional procedures with gastrointestinal suture/stapling (OR 1.84). Benchmark cutoffs for conversional BS were ≤4.5% re-intervention, ≤8.3% re-operation 90-days postoperatively. At 2-years (IQR 1-3) 15.6% of benchmark patients required a reoperation. CONCLUSION: Secondary BS is safe, although postoperative morbidity exceeds the established benchmarks for primary BS. The excess morbidity is due to an increased risk of gastrointestinal leakage and higher need for intensive care. The considerable rate of tertiary BS warrants expertise and future research to optimize the management of non-success after BS.

Does the non-absorbable suture closure of the jejunal mesenteric defect reduce the incidence and severity of internal hernias after laparoscopic Roux-en-Y gastric bypass?

PURPOSE: Internal hernias (IH) are frequent complications after laparoscopic Roux-en-Y gastric bypass (LRYGB). Closure of the jejunal mesenteric and the Petersen defect reduces IH incidence in prospective and retrospective trials. This study investigates whether closing the jejunal mesenteric space alone by non-absorbable suture and splitting the omentum can be beneficial to prevent IH after LRYGB. METHODS: Observational cohort study of 785 patients undergoing linear LRYGB including omental split at a single institution, with 493 patients without jejunal mesenteric defect closure and 292 patients with closure by non-absorbable suture, and a minimal follow-up of 2 years. Patients were assessed for appearance and severity of IH. Additionally, open mesenteric gaps without herniated bowel as well as early obstructions due to kinking of the entero-enterostomy (EE) were explored. RESULTS: Through primary mesenteric defect closure, the rate of manifest jejunal mesenteric and Petersen IH could be reduced from 6.5 to 3.8%, but without reaching statistical significance. The most common location for an IH was the jejunal mesenteric space, where defect closure during primary surgery reduced the rate of IH from 5.3 to 2.4%. Higher weight loss seemed to increase the risk of developing an IH. CONCLUSION: The closure of the jejunal mesenteric defect by non-absorbable suture may reduce the rate of IH at the jejunal mesenteric space after LRYGB. However, the beneficial effect in our collective is smaller than expected, particularly in patients with good weight loss. The Petersen IH rate remained low by consequent T-shape split of the omentum without suturing of the defect.

Tumor Infiltration by OX40+ Cells Enhances the Prognostic Significance of CD16+ Cell Infiltration in Colorectal Cancer.

OBJECTIVES: Analysis of tumor immune infiltration has been suggested to outperform tumor, node, metastasis staging in predicting clinical course of colorectal cancer (CRC). Infiltration by cells expressing OX40, a member of the tumor necrosis factor receptor family, or CD16, expressed by natural killer cells, monocytes, and dendritic cells, has been associated with favorable prognosis in patients with CRC. We hypothesized that assessment of CRC infiltration by both OX40+ and CD16+ cells might result in enhanced prognostic significance. METHODS: Colorectal cancer infiltration by OX40 and CD16 expressing cells was investigated in 441 primary CRCs using tissue microarrays and specific antibodies, by immunohistochemistry. Patients' survival was evaluated by Kaplan-Meier and log-rank tests. Multivariate Cox regression analysis, hazard ratios, and 95% confidence intervals were also used to evaluate prognostic significance of OX40+ and CD16+ cell infiltration. RESULTS: Colorectal cancer infiltration by OX40+ and CD16+ cells was subclassified into 4 groups with high or low infiltration levels in all possible combinations. High levels of infiltration by both OX40+ and CD16+ cells were associated with lower pT stage, absence of peritumoral lymphocytic (PTL) inflammation, and a positive prognostic impact. Patients bearing tumors with high infiltration by CD16+ and OX40+ cells were also characterized by significantly longer overall survival, as compared with the other groups. These results were confirmed by analyzing an independent validation cohort. CONCLUSIONS: Combined infiltration by OX40+ and CD16+ immune cells is an independent favorable prognostic marker in CRC. The prognostic value of CD16+ immune cell infiltration is significantly improved by the combined analysis with OX40+ cell infiltration.

[Long-Term Results of Sleeve Gastrectomy]. / Langzeit-Resultate der Schlauchgastrektomie.

Long-Term Results of Sleeve Gastrectomy Abstract. Sleeve gastrectomy (SG) is the most frequently performed bariatric procedure worldwide today. SG has been validated as a safe and effective treatment for morbid obesity. However, long-term results are still rare. Current studies present a slightly lower weight loss compared to Roux-en-Y gastric bypass (RYGB). Mean excess weight loss (EWL) beyond 10 years is around 50 %. SG has a positive effect on comorbidities (e. g. type 2 diabetes, hypertension, dyslipidemia). Diabetes remission is described in up to 62 %. Long-term issue is gastro-esophageal reflux, either persistent or de-novo which can be treated conservatively in most patients. In patients without adequate response to medical treatment, reoperation can be necessary. Other reasons for revisional surgery are insufficient weight loss. SG can be considered as a safe and fairly effective procedure.

High OX40 expression in recurrent ovarian carcinoma is indicative for response to repeated chemotherapy.

BACKGROUND: Ovarian carcinoma (OC) is the fifth most common female cancer and mostly diagnosed at an advanced stage. Surgical debulking is usually followed by adjuvant platinum-based chemotherapy. Only few biomarkers are known to be related to chemosensitivity. OX40 is a TNF receptor member and expressed on activated CD4+ and CD8+ T cells. It is known that OX40 signaling promotes survival and responds to various immune cells of the innate and adaptive immune system. Therefore we investigated the indicative value of OX40 expression for recurrence and survival in OC. METHODS: A tissue microarray of biopsies of mostly high-grade primary serous OC and matched recurrences of 47 patients was stained with OX40. Recurrence within 6 months of the completion of platinum-based chemotherapy was defined as chemoresistance. RESULTS: Chemosensitivity correlated significantly with high OX40 positive immune cell density in primary cancer biopsies (p = 0.027). Furthermore patients with a higher OX40 expression in recurrent cancer biopsies showed a better outcome in recurrence free survival (RFS) (p = 0.017) and high OX40 expression was associated with chemosensitivity (p = 0.008). OX40 positive TICI in recurrent carcinomas significantly correlated with IL-17 positive tumor infiltrating immune cells in primary carcinomas (r s = 0.34; p = 0.023). Univariate cox regression analysis revealed a significant longer RFS and higher numbers of chemotherapy cycles for high OX40 tumor cell expression in recurrent cancer biopsies (HR 0.39, 95%CI 0.16-0.94, p = 0.036 and 1.28, 95%CI 1.05-1.55; p = 0.013). CONCLUSION: High OX40 expression in OC is correlated with chemosensitivity and improved RFS in OC. Patients might therefore benefit from a second line therapy.

Colon Perfusion Patterns During Colorectal Resection Using Visible Light Spectroscopy.

BACKGROUND: The impact of blood supply to the anastomosis on development of anastomotic leakage is still a matter of debate. Considering that bowel perfusion may be affected by manipulation during surgery, perfusion assessment of the anastomosis alone may be of limited value. We propose perfusion assessment at different time points during surgery to explore the dynamics of bowel perfusion during colorectal resection and its impact on outcome. METHODS: In this prospective cohort study, patients undergoing elective colorectal resection were eligible. Colon perfusion was evaluated using visible light spectroscopy. Main outcome was the difference in colon perfusion, quantified by measuring tissue oxygen saturation (StO2) in the colonic serosa, before and after anastomosis during surgery. RESULTS: We included 58 patients between July 2013 and November 2015. Colon perfusion increased by an average of 5.9% StO2 during surgery (95% confidence interval 3.1, 8.8; P < 0.001). The number of patients with abnormal perfusion (defined as StO2 < 65%) decreased from 50% at the beginning to 24% by the end of surgery. Six patients (10%) developed anastomotic leaks (AL), of which five patients had abnormal perfusion at the beginning of surgery, whereas four patients had normal StO2 at the anastomosis. CONCLUSION: Colon perfusion significantly increased during colorectal surgery. Considering that one quarter of patients had suboptimal anastomotic perfusion without developing AL, impaired blood flow at the anastomosis alone does not seem to be critical. Further investigations including more patients are necessary to evaluate the impact of perioperative parameters on colon perfusion, anastomotic healing and surgical outcome.

MPO density in primary cancer biopsies of ovarian carcinoma enhances the indicative value of IL-17 for chemosensitivity.

BACKGROUND: Cancer of the ovary is mostly discovered at a late stage and cannot be removed by surgery alone. Therefore surgery is usually followed by adjuvant chemotherapy. However, few reliable biomarkers exist to predict response to chemotherapy of ovarian cancer. Previously, we could demonstrate that IL-17 density is indicative for chemosensitivity. This study focuses on the predictive value of myeloperoxidase (MPO) concerning response to chemotherapy of ovarian cancer. METHODS: Biopsies of mostly high-grade primary serous ovarian carcinomas and their matched recurrences were stained with MPO after fixation in formalin and embedding in paraffin. For this staining the technique of tissue-microarray was used. Recurrence within 6 months of the completion of platinum-based chemotherapy was defined as chemoresistance as previously publised. Data for MPO could be analyzed in 92 biopsies. RESULTS: MPO and IL-17 positive immune cells correlated significantly in biopsies of primary and recurrent carcinomas (r s = 0.41; p = 0.004 and r s = 0.40; p = 0.007, respectively). MPO expression alone did not predict response to chemotherapy, but in multivariate cox regression analysis including age, residual disease, number of chemotherapy cycles, FIGO classification and combined categorized MPO and IL-17 cell densities of primary cancer biopsies, the combination of both immune markers was an independent prognostic factor for recurrence-free survival (p = 0.013, HR = .23, 95CI = 0.07-0.73). There was no chemoresistant patient in the subgroup of MPO + IL-17+, neither in primary nor in recurrent cancer biopsies. CONCLUSIONS: High MPO positive cell density enhances the indicative value of IL-17 for response to chemotherapy in ovarian carcinoma. Although, these results have to be validated in a larger cohort.

Primary non-closure of mesenteric defects in laparoscopic Roux-en-Y gastric bypass: reoperations and intraoperative findings in 146 patients.

BACKGROUND: Internal hernias (IH) after laparoscopic Roux-en-Y gastric bypass (LRYGB) have been reported with an incidence of 11 %. IH can lead to bowel incarceration and potentially bowel necrosis. The aim of this study was to analyze reoperations and intraoperative findings in a cohort of patients with unclosed mesenteric defects. METHODS: From a prospective database of patients with LRYGB, we selected as primary cohort patients with non-closure of mesenteric defects and abdominal reoperation for analysis. The data included pre-, intra- and post-operative findings, computed tomogram results and laboratory test results. This group underwent a very very long limb LRYGB, at that time the institutional standard technique. Additionally, a more recently operated cohort with primary closure of mesenteric defects was also analyzed. RESULTS: We identified 146 patients with primary non-closure and reoperation, mean age of 43.8 years. The main indication for reoperation was unclear abdominal pain in 119 patients with 27 patients undergoing a reoperation for other reasons (weight regain, prophylactic surgical inspection of mesenteric defects). Median time and mean excess weight loss from RYGB to reoperation were 41.1 months and 62.7 %, respectively. The incidence of IH was 14.4 %, with all patients with an IH being symptomatic. Conversion rate from laparoscopic to open surgery was 5.5 %, mortality 0.7 % and morbidity 3.4 %. Thirty-one patients underwent a second re-look laparoscopy. Eleven patients had recurrent open mesenteric defects. Three hundred and sixteen patients who underwent primary closure of the mesenteric defects had a reoperation rate of 13.6 % and an IH rate of 0.6 %. CONCLUSION: The incidence of IH in patients without closure of mesenteric defects and reoperation is high and substantially higher compared to patients with primary closure of mesenteric defects. Patients with or without closure of mesenteric defects following LRYGB with acute, chronic or recurrent pain should be referred to a bariatric surgeon for diagnostic laparoscopy.

Thickness distribution of the glenohumeral joint cartilage: a quantitative study using computed tomography.

PURPOSE: Among late signs like sclerosis, cysts and osteophytes, alteration of cartilage is a common problem in osteoarthritis. To detect abnormal states in the glenohumeral joint, the physiologic distribution of the cartilage thickness must be known, which will allow physicians to better advise patients. High-resolution computed tomography (CT) data in soft tissue kernel provide highly accurate quantitative results and are a useful method to determine the geometrical situation of the glenohumeral joint. The objective of this study was to characterize the distribution of the thickness of the glenohumeral joint cartilage using CT. METHODS: To investigate the distribution of thickness of the joint cartilage, CT images in soft tissue kernel of nine specimens were analyzed using image visualization software. Statistical analysis of the obtained data was performed using the ANOVA test. RESULTS: Results showed different patterns in the glenoid cavity than in humeral head. Cartilage thickness in all glenoids showed maxima in the inferior and anterior portion, whereas central areas are covered with the thinnest cartilage layer. Maximum cartilage thickness in the humeral head was found in the central and superior parts. CONCLUSION: We could show that the distribution of cartilage thickness in the glenohumeral joint is not homogenous and that there exist several reproducible patterns. Evaluation of cartilage thickness in the glenohumeral joint is of high interest in basic and clinical research.

Comparison of 2D 4K vs. 3D HD laparoscopic imaging systems in bariatric surgery: study protocol for a randomized controlled prospective trial.

BACKGROUND: Vision is an important and defining element of laparoscopy and significantly affects the outcome of surgery in terms of time, error, and precision. Several new imaging systems have become available for laparoscopic surgery, including three-dimensional (3D) high-definition (HD) and two-dimensional (2D) ultra-high-resolution (4K) monitors. 3D HD systems offer a number of potential benefits to surgeons and patients over traditional 2D systems, including reduced operating time, blood loss, and hospital stay. However, the performance of 3D systems against the new, ultra-high definition 4K systems is barely known and highly controversial. There is a paucity of studies comparing them in clinical settings. The aim of this study is to compare 2D 4K and 3D HD perspectives in gastric bypass surgery. METHODS: Forty-eight patients with an indication for gastric bypass will be randomized to receive laparoscopic gastric bypass surgery using either 2D 4K or 3D HD systems. The operations will be performed by a well-coordinated team of three senior surgeons. The primary outcome is operative time. Secondary outcomes include intraoperative complications, blood loss, operator workload as assessed by the validated Surg-TLX questionnaire, and postoperative complications according to the Clavien-Dindo classification. An interim analysis is planned after enrollment of 12 participants for each group. DISCUSSION: This prospective, randomized trial is designed to test the hypothesis that the use of a 3D HD system will result in a significant improvement in operative time compared to a 2D 4K system in bariatric surgery. The objective is to provide clinical evidence for new laparoscopic imaging systems and to evaluate potential benefits. TRIAL REGISTRATION: This trial is registered at clinicaltrials.gov under the identifier NCT05895058. Registered 30 May 2023. BASEC2023-D0014 [Registry ID Swissethics, approved 3 May 2023]. SNCTP000005489 [SNCTP study register, last updated 13 July 2023].

Breaking down barriers to bariatric care: a qualitative study on how telemedicine could transform patient experiences in a Swiss monocentric setting.

OBJECTIVE: Telemedicine is becoming an increasingly feasible option for patients with chronic diseases due to its convenience, cost-effectiveness and ease of access. While there are certain limitations, the benefits can be appreciated by those seeking repetitive care. The perception of telemedicine as an alternative to recurrent, in-person appointments for patients with obesity in structured bariatric programmes is still unclear. This content analysis' primary endpoint was to explore how patients within our bariatric programme perceived telemedicine and virtual consultations as a new way of communication during COVID-19. DESIGN: A qualitative study using semistructured interviews and qualitative content analysis method by Elo and Kyngäs following four steps: data familiarisation, coding and categorising with Quirkos software and final interpretation guided by developed categories. SETTING: University Hospital, Switzerland. PARTICIPANTS: We conducted 33 interviews with 19 patients from a structured bariatric programme. RESULTS: Most patients shared positive experiences, acknowledging the convenience and accessibility of virtual appointments. Others voiced concerns, especially regarding telemedicine's limitations. These reservations centred around the lack of physical examinations, difficulties in fostering connections with healthcare providers, as well as barriers stemming from language and technology. The research identified a spectrum of patient preferences in relation to telemedicine versus in-person visits, shaped by the immediacy of their concerns and their availability. CONCLUSION: While telemedicine is increasingly accepted by the public and provides accessible and cost-effective options for routine follow-up appointments, there are still obstacles to overcome, such as a lack of physical examination and technological limitations. However, integrating virtual alternatives, like phone or video consultations, into routine bariatric follow-ups could improve continuity and revolutionise bariatric care.

Assessment of resectability of pancreatic cancer using novel immersive high-performance virtual reality rendering of abdominal computed tomography and magnetic resonance imaging.

PURPOSE: Virtual reality (VR) allows for an immersive and interactive analysis of imaging data such as computed tomography (CT) and magnetic resonance imaging (MRI). The aim of this study is to assess the comprehensibility of VR anatomy and its value in assessing resectability of pancreatic ductal adenocarcinoma (PDAC). METHODS: This study assesses exposure to VR anatomy and evaluates the potential role of VR in assessing resectability of PDAC. Firstly, volumetric abdominal CT and MRI data were displayed in an immersive VR environment. Volunteering physicians were asked to identify anatomical landmarks in VR. In the second stage, experienced clinicians were asked to identify vascular involvement in a total of 12 CT and MRI scans displaying PDAC (2 resectable, 2 borderline resectable, and 2 locally advanced tumours per modality). Results were compared to 2D standard PACS viewing. RESULTS: In VR visualisation of CT and MRI, the abdominal anatomical landmarks were recognised by all participants except the pancreas (30/34) in VR CT and the splenic (31/34) and common hepatic artery (18/34) in VR MRI, respectively. In VR CT, resectable, borderline resectable, and locally advanced PDAC were correctly identified in 22/24, 20/24 and 19/24 scans, respectively. Whereas, in VR MRI, resectable, borderline resectable, and locally advanced PDAC were correctly identified in 19/24, 19/24 and 21/24 scans, respectively. Interobserver agreement as measured by Fleiss κ was 0.7 for CT and 0.4 for MRI, respectively (p < 0.001). Scans were significantly assessed more accurately in VR CT than standard 2D PACS CT, with a median of 5.5 (IQR 4.75-6) and a median of 3 (IQR 2-3) correctly assessed out of 6 scans (p < 0.001). CONCLUSION: VR enhanced visualisation of abdominal CT and MRI scan data provides intuitive handling and understanding of anatomy and might allow for more accurate staging of PDAC and could thus become a valuable adjunct in PDAC resectability assessment in the future.

A comparison of subchondral bone mineralization between the glenoid cavity and the humeral head on 57 cadaverous shoulder joints.

PURPOSE: Mineralization distribution of the subchondral bone plate can be used as a marker for long-term stress distribution in diarthrodial joints. Severe injuries or pathological changes of the glenohumeral joint often end in osteoarthritis, where shoulder arthroplasty has become the treatment of choice. The computed tomography osteoabsorptiometry (CT-OAM) is a non-invasive method to determine the distribution of the mineralization of the subchondral bone plate in vivo, which is an important factor concerning the implantation of orthopedic endoprostheses. The aim of this study was to investigate the mineralization of both joint partners of the glenohumeral joint and to compare them with each other. METHODS: The distribution of the mineralization of the subchondral bone plate of 57 shoulder specimens was determined by means of CT-OAM. To evaluate a correlation between age and localization of subchondral mineralization maxima, the Chi-square test correlation test was applied. RESULTS: Forty-nine glenoid cavities (86 %) showed a bicentric mineralization distribution pattern with anterior and posterior maxima, only 8 glenoid cavities (14 %) revealed a monocentric mineralization pattern with anterior maxima. Forty-five humeral heads (79 %) showed a bicentric distribution pattern with anterior and posterior maxima, 12 humeral heads (21 %) could be classified as monocentric with a centro-posterior pronounced maximum. CONCLUSIONS: We could demonstrate that stress distribution in both joint partners of the glenohumeral joint is inhomogeneous and characteristically bicentric due to the physiological incongruity. Monocentric mineralization patterns can result as a cause of age-related loss of incongruity.

Long-term outcome after biliopancreatic diversion with duodenal switch: a single-center experience with up to 20 years follow-up.

BACKGROUND: Biliopancreatic diversion with duodenal switch (BPD/DS) is the most effective standard bariatric procedure in terms of weight loss and remission of co-morbidities but carries the risk of severe long-term side effects. OBJECTIVE: The aim of this study was to analyze the long-term effects of BPD/DS in terms of morbidity, weight loss, remission of associated medical problems, deficiencies, and reoperations. SETTING: Academic teaching hospital, Switzerland. METHODS: This is a retrospective, single-center study of prospectively collected data of all patients who underwent BPD/DS from 1999 to 2011 with a minimal follow-up (FU) of 10 years. RESULTS: A total of 116 patients (83.6% female) underwent BPD/DS with a mean initial body mass index (BMI) of 47 ± 6.5 kg/m2. Of these, 68% of the procedures were performed in open technique and 32% laparoscopically. The majority (76.7%) of patients had laparoscopic adjustable gastric banding before BPD/DS. The mean FU time was 14 ± 4.4 years and the FU rate at 5, 10, and 14 years was 95.6% (n = 108), 90% (n = 98), and 75.3% (n = 70), respectively. The mean excess BMI loss at 5, 10, and 14 years was 78% ± 24.1%, 76.5% ± 26.7%, and 77.8% ± 33.8%, respectively. Complete (n = 22) or partial remission (n = 4) of type 2 diabetes was observed in 92.8% of patients. Forty reoperations were necessary in 34 patients (29.3%) because of malnutrition or refractory diarrhea (n = 13), insufficient weight loss or weight rebound (n = 7), reflux or stenosis (n = 10), and various/combined indications (n = 10). The mean time to reoperation was 7.7 ± 5 years. There were no procedure-related deaths in the short or long term. CONCLUSIONS: BPD/DS offers sustainable long-term weight loss but is associated with important side effects that may be acceptable in selected patients with a high initial BMI (>50 kg/m2) and/or for nonresponders after primary restrictive procedures. Regular FU is necessary to detect and treat malnutrition and vitamin deficiencies.

Mid-Term Outcomes After Conversion Procedures Following Laparoscopic Sleeve Gastrectomy.

PURPOSE: In the long term, laparoscopic sleeve gastrectomy (SG) may be associated with insufficient weight loss (IWL), gastroesophageal reflux disease (GERD), and persistence or relapse of associated medical problems. This study's objective is to present mid-term results regarding weight loss (WL), evolution of associated medical problems, and reoperation rate of patients who underwent a conversion after SG. METHODS: Retrospective single-center analysis of patients with a minimal follow-up of 2 years after conversion. RESULTS: In this series of 549 SGs, 84 patients (15.3%) underwent a conversion, and 71 met inclusion criteria. They were converted to short biliopancreatic limb Roux-en-Y gastric bypass (short BPL RYGB) (n = 28, 39.4%), biliopancreatic diversion with duodenal switch (BPD/DS) (n = 19, 26.8%), long biliopancreatic limb Roux-en-Y gastric bypass (long BPL RYGB) (n = 17, 23.9%), and re-sleeve gastrectomy (RSG) (n = 7, 9.9%). Indications were GERD (n = 24, 33.8%), IWL (n = 23, 32.4%), IWL + GERD (n = 22, 31.0%), or stenosis/kinking of the sleeve (n = 2, 2.8%). The mean pre-revisional body mass index (BMI) was 38.0 ± 7.5 kg/m2. The mean follow-up time after conversion was 5.1 ± 3.1 years. The overall percentage of total weight loss (%TWL) was greatest after BPD/DS (36.6%) and long BPL RYGB (32.9%) compared to RSG (20.0%; p = 0.004; p = 0.049). In case of GERD, conversion to Roux-en-Y gastric bypass (RYGB) led to a resolution of symptoms in 79.5%. 16.9% of patients underwent an additional revisional procedure. CONCLUSION: In the event of IWL after SG, conversion to BPD/DS provides a significant and sustainable additional WL. Conversion to RYGB leads to a reliable symptom control in patients suffering from GERD after SG.

Correlation between mineralization and mechanical strength of the subchondral bone plate of the humeral head.

BACKGROUND: One of the main problems in shoulder arthroplasty is the fixation of the prosthesis, where the subchondral bone plate plays an important role. Subchondral mineralization patterns represent the loading history of a joint and give information about the individual biomechanical situation. The objective of this study was to determine if a correlation between subchondral mineralization and mechanical strength in the humeral head exists. MATERIALS AND METHODS: Subchondral mineralization of 32 shoulder specimens was investigated by use of computed tomography (CT) osteoabsorptiometry. The previously dissected specimens were scanned axially in a CT scanner, and the obtained data sets were transferred into an image analyzing system. Maximum intensity projection was used to evaluate the density distribution of the subchondral bone plate. To get information about mechanical strength of the subchondral bone, each specimen was investigated at 29 predefined points by means of an indentation-testing machine. RESULTS: The maximum strength was mostly detected in the center (monocentric pattern) or in anterior and posterior areas of the articular surface (bicentric pattern). The distribution of mineralization showed the same 2 reproducible patterns. The coefficient of correlation between mechanical strength and mineralization shown on CT was between 0.59 and 0.96. The obtained information was statistically significant (P < .01). CONCLUSION: Mechanical strength and subchondral mineralization in the humeral head are significantly associated (P < .01). As a consequence of these findings, CT osteoabsorptiometry can be indirectly used to give information about bone quality in vivo. Our findings could be useful for the development of new fixation methods in shoulder surgery (eg, humeral resurfacing arthroplasty).

Intraoperative Patterns of Gastric Microperfusion During Laparoscopic Roux-en-Y Gastric Bypass.

INTRODUCTION: Visible light spectroscopy (VLS) represents a sensitive, non-invasive method to quantify tissue oxygen levels and detect hypoxemia. The aim of this study was to assess the microperfusion patterns of the gastric pouch during laparoscopic Roux-en-Y gastric bypass (LRYGB) using the VLS technique. METHODS: Twenty patients were enrolled. Tissue oxygenation (StO2%) measurements were performed at three different localizations of the gastric wall, prior and after the creation of the gastric pouch, and after the creation of the gastro-jejunostomy. RESULTS: Prior to the creation of the gastric pouch, the lowest StO2% levels were observed at the level of the distal esophagus with a median StO2% of 43 (IQR 40.8-49.5). After the creation of the gastric pouch and after the creation of the gastro-jejunostomy, the lowest StO2% levels were recorded at the level of the His angle with median values of 29% (IQR 20-38.5) and 34.5% (IQR 19-39), respectively. The highest mean StO2 reduction was recorded at the level of the His angle after the creation of the gastric pouch, and it was 18.3% (SD ± 18.1%, p < 0.001). A reduction of StO2% was recorded at all localizations after the formation of the gastro-jejunostomy compared to the beginning of the operation, but the mean differences of the StO2% levels were statistically significant only at the resection line of the pouch and at the His angle (p = 0.044 and p < 0.001, respectively). CONCLUSION: Gastric pouch demonstrates reduction of StO2% during LRYGB. VLS is a useful technique to assess microperfusion patterns of the stomach during LRYGB.