Prognostic impact of positive microscopic margins (R1 resection) in patients with GIST (gastrointestinal stromal tumours): Results of a multicenter European study.

BACKGROUND: Although several prognostic factors in GIST have been well studied such as tumour size, mitotic rate, or localization, the influence of microscopic margins or R1 resection remains controversial. The aim of this study was to evaluate the influence of R1 resection on the prognosis of GIST in a large multicentre retrospective series of patients. METHODS: From 2001 to 2013, 1413 patients who underwent surgery for any site of GIST were identified from 61 European centers. 1098 patients were included, excluding synchronous metastases, concurrent malignancies, R2 resection or GIST recurrence. Tumour rupture (TR) was reclassified according to the Oslo sarcoma classification. Cox proportional hazards ratio and Kaplan-Meier survival estimates were used to analyse 5-year recurrence-free survival (RFS). RESULTS: Of 1098 patients, 38 (3%) underwent R1 resection with a risk of TR of 11%. The 5-year RFS was 89.6% with a median follow-up of 81 months [range: 31.2-152 months]. On univariate analysis, lower RFS was significantly associated with R1 resection [HR = 2.13; p = 0.04], high risk score according to the modified NIH classification, administration of adjuvant therapy [HR = 2.24; p < 0.001] and intraoperative complications [HR = 2.82; p < 0.001]. Only intraoperative complications [HR = 1.79; p = 0.02] and high risk according to the modified NIH classification including the updated definition of TR [HR = 3.43; p = 0.04] remained significant on multivariate analysis. CONCLUSION: This study shows that positive microscopic margins are not an independent predictive factor for RFS in GIST when taking into account the up-dated classification of TR. R1 resection may be considered a reasonable alternative to avoid major functional sequelae and should not lead to reoperation.

Conditional cumulative incidence of postoperative complications stratified by complexity classification for laparoscopic liver resection: Optimization of in-hospital observation.

BACKGROUND: The optimal in-hospital observation periods associated with minimal risks of complications and unplanned readmission after laparoscopic liver resection are unknown. The purpose of this study was to assess changes in the risks of postoperative complications over time. METHODS: Surgical complexity of laparoscopic liver resection was stratified into grades I (low complexity), II (intermediate), and III (high) using our 3-level complexity classification. The cumulative incidence rate and conditional probability of postoperative complication and risk factors for complication Clavien-Dindo grade ≥II (defined as treatment-requiring complications) were assessed. RESULTS: The cumulative incidence of treatment-requiring complications was higher in patients undergoing grade III resection than in patients undergoing grade I resection (32.3% vs 10.4%, P < .001) and grade II resection (32.3% vs 20.7%, P = .019). The conditional probability of postoperative complication stratified by our complexity classification decreased over time and was <10% for patients undergoing grade I resection on postoperative day 1, grade II resection on postoperative day 4, and grade III resection on postoperative day 10. CONCLUSION: The conditional cumulative incidence of treatment-requiring complications for patients undergoing laparoscopic liver resection is well stratified based on the 3-level complexity classification. Conditional complication risk analysis stratified by the 3 complexity grades may be useful for optimizing in-hospital observation after laparoscopic liver resection.

Prognostic role of infracentimetric colorectal liver metastases.

BACKGROUND: The number of lesions and the size of the largest (CRLMmax) have been widely investigated as prognostic factors in patients with colorectal liver metastases (CRLM). The aim of the present study was to assess whether, in patients undergoing curative liver resection, the presence of infracentimetric lesions could affect recurrence-free survival (RFS) and overall survival (OS). METHODS: Patients who underwent a liver resection for CRLM between 2001 and 2019 were included. The size of CRLM was measured on the surgical specimen. The best cut-off of the smallest lesion (CRLMmin) associated with RFS was determined through the time-dependent ROC analysis. A multivariate Cox regression analysis was carried out. RESULTS: Overall, 227 patients were included. Median follow-up time was 50 months [IQR 26-84]. Recurrence occurred for 151 (66.5%) patients (liver recurrence in 67.5%, while exclusive extra-hepatic recurrence in 32.5%). The best cut-off for CRLMmin associated with RFS was 9 mm, with 12- and 24-month td-AUC 0.56 and 0.52 respectively. CRLMmin ≤ 9 mm was found to be an independent prognostic factor that impairs RFS at multivariate analysis (HR 1.534 (1.02-2.32), p = 0.042). In particular, CRLMmin ≤ 9 mm was correlated with impaired hepatic RFS (HR 1.860 (1.15-3.01), p = 0.011), but not extra-hepatic RFS. CONCLUSIONS: Infracentimetric metastases (≤ 9 mm) are an independent prognostic factor that impairs hepatic RFS. This result suggests the potential benefit of neoadjuvant chemotherapy (CT) also in selected patients with initially resectable lesions, in case of CRLM ≤ 9 mm on preoperative imaging.

Predictors of discharge timing and unplanned readmission after laparoscopic liver resection.

BACKGROUND: The aim of the study was to determine the predictors of discharge timing and 90-day unplanned readmission after laparoscopic liver resection (LLR). METHODS: Consecutive LLR performed at the "Institut Mutualiste Montsouris" between 2000 and 2019 were retrieved from a prospectively maintained database. Length of stay (LOS) was stratified according to surgical difficulty and was categorized as early (LOS<25th percentile), routine (25th percentile<75th percentile), and delayed discharge otherwise. Uni-and-multivariate analyses were conducted to determine the factors associated with the time of discharge and 90-day unplanned readmission. RESULTS: Early discharge occurred in 15.7% patients whereas delayed discharge occurred in 20.6% patients. Concomitant pancreatic resections (OR 26.8, 95% CI 5.75-125, p < 0.0001) and removal of colorectal primary tumors (OR 7.14, 95% CI 3.98-12.8, p < 0.0001) were the strongest predictors of delayed discharge whereas ERP implementation was the strongest predictor of early discharge (OR 7.4, 95% CI 4.60-11.9, p < 0.0001). Unplanned readmission rate was lower among early discharged patients (7.4% vs. 23.8%, p < 0.0001). Bile leakage was the strongest predictor of 90-day unplanned readmission (OR 3.8, 95% CI 1.12-15.8, p = 0.045). CONCLUSION: Concomitant colorectal or pancreatic resections were the strongest predictors of delayed discharge. Postoperative bile leakage was the strongest predictor of 90-day unplanned readmission following LLR.

Imaging of postoperative complications following Ivor-Lewis esophagectomy.

Postoperative imaging plays a key role in the identification of complications after Ivor-Lewis esophagectomy (ILE). Careful analysis of imaging examinations can help identify the cause of the presenting symptoms and the mechanism of the complication. The complex surgical procedure used in ILE results in anatomical changes that make imaging interpretation challenging for many radiologists. The purpose of this review was to make radiologists more familiar with the imaging findings of normal anatomical changes and those of complications following ILE to enable accurate evaluation of patients with an altered postoperative course. Anastomotic leak, gastric conduit necrosis and pleuropulmonary complications are the most serious complications after ILE. Computed tomography used in conjunction with oral administration of contrast material is the preferred diagnostic tool, although it conveys limited sensitivity for the diagnosis of anastomotic fistula. In combination with early endoscopic assessment, it can also help early recognition of complications and appropriate therapeutic management.

Quality of oncological resection criteria in minimally invasive esophagectomy.

BACKGROUND: Even though minimally invasive esophageal surgery (MIE) is spreading, questions remain regarding its oncological outcomes. The aim of this study was to assess the quality of oncological resection criteria in MIE. METHODS: All patients undergoing a two-way Ivor Lewis esophagectomy for esophageal or junctional cancer between 2010 and 2020 in a single tertiary upper gastrointestinal surgery ward were analyzed retrospectively. The following oncological criteria were analyzed: lymph node (LN) harvest and location, positive lymph node rate, margins, and R0 rates. They were compared between the MIE group (thoracoscopy + laparoscopy) and the hybrid group (H/O, thoracotomy + laparoscopy). RESULTS: Among the 240 patients included, 34 (14%) had MIE and 206 a hybrid esophagectomy. Main surgical indication was lower thoracic adenocarcinoma and the rate of neoadjuvant treatments administered (chemotherapy or chemoradiotherapy) was comparable between both groups (p = 1.0). LN harvest was significantly higher in the MIE group (31 ± 9 vs. 28 ± 9, p = 0.04) as well as thoracic LN harvest (14 ± 7 vs. 11 ± 5, p = 0.002). When analyzing patients according to T stage and response to neoadjuvant treatments, patients with T1 and T2 tumors and patients with a poor pathological response (TRG3, 4, 5) had a significantly higher LN harvest when undergoing a minimally invasive approach (p = 0.021 and p = 0.01, respectively). Positive LN rates (1.26 ± 3.63 in the MIE group vs. 1.60 ± 2.84 in the H/O group, p = 0.061), R0 rates (97% vs. 98.5%, p = 0.46) as well as proximal (p = 0.083), distal (p = 0.063), and lateral (p = 0.15) margins were comparable between both approaches. CONCLUSION: MIE seems oncologically safe and may even be better than the open approach in terms of LN harvest especially in patients with T1 and T2 tumors and in poor responders.

Feasibility and outcomes of multiple simultaneous laparoscopic liver resections.

INTRODUCTION: Surgeons often remain reluctant to consider laparoscopic approach in multiple liver tumors. This study assessed feasibility and short-term results of patients who had more than 3 simultaneous laparoscopic liver resections (LLR). METHODS: All consecutive patients who underwent LLR for primary or secondary malignancies between 2009 and 2019 were analyzed. After exclusion of major LLR, patients were divided into three groups: less than three (Group A), between three and five (Group B), and more than five resections (Group C) in the same procedure. Intraoperative details, postoperative outcomes, and textbook outcome (TO) were compared in the 3 groups. RESULTS: During study period, 463 patients underwent minor LLR. Among them, 412 (88.9%) had less than 3 resections, 38 (8.2%) between 3 and 5 resections, and 13 (2.8%) more than 5 resections. Despite a difficulty score according to IMM classification comparable in the 3 groups (with high difficulty grade 3 procedures of 16.5% vs. 15.7% vs. 23.1% in Group A, B, and C, respectively, p = 0.124), mean operative time was significantly longer in Group C (p = 0.039). Blood loss amount (p = 0.396) and conversion rate (p = 0.888) were similar in the 3 groups. Rate of R1 margins was not significantly different between groups (p = 0.078). Achievement of TO was not different between groups (p = 0.741). In multivariate analysis, non-achievement of TO was associated with difficulty according to IMM classification (OR = 2.29 (1.33-3.98)). CONCLUSION: Since intra- and post-operative outcomes and quality of resection are comparable, multiple liver resections should not preclude the laparoscopic approach.

Long-term stability of the chronic epidural wireless recorder WIMAGINE in tetraplegic patients.

Objective.The evaluation of the long-term stability of ElectroCorticoGram (ECoG) signals is an important scientific question as new implantable recording devices can be used for medical purposes such as Brain-Computer Interface (BCI) or brain monitoring.Approach.The long-term clinical validation of wireless implantable multi-channel acquisition system for generic interface with neurons (WIMAGINE), a wireless 64-channel epidural ECoG recorder was investigated. The WIMAGINE device was implanted in two quadriplegic patients within the context of a BCI protocol. This study focused on the ECoG signal stability in two patients bilaterally implanted in June 2017 (P1) and in November 2019 (P2).Methods. The ECoG signal was recorded at rest prior to each BCI session resulting in a 32 month and in a 14 month follow-up for P1 and P2 respectively. State-of-the-art signal evaluation metrics such as root mean square (RMS), the band power (BP), the signal to noise ratio (SNR), the effective bandwidth (EBW) and the spectral edge frequency (SEF) were used to evaluate stability of signal over the implantation time course. The time-frequency maps obtained from task-related motor activations were also studied to investigate the long-term selectivity of the electrodes.Mainresults.Based on temporal linear regressions, we report a limited decrease of the signal average level (RMS), spectral distribution (BP) and SNR, and a remarkable steadiness of the EBW and SEF. Time-frequency maps obtained during motor imagery, showed a high level of discrimination 1 month after surgery and also after 2 years.Conclusions.The WIMAGINE epidural device showed high stability over time. The signal evaluation metrics of two quadriplegic patients during 32 months and 14 months respectively provide strong evidence that this wireless implant is well-suited for long-term ECoG recording.Significance.These findings are relevant for the future of implantable BCIs, and could benefit other patients with spinal cord injury, amyotrophic lateral sclerosis, neuromuscular diseases or drug-resistant epilepsy.

Validation of the IMM classification in laparoscopic repeat liver resections for colorectal liver metastases.

BACKGROUND: To validate the Institut Mutualiste Montsouris classification as a difficulty scoring system applicable to laparoscopic repeat liver resections and identify risk-factors of unexpected difficulty. METHODS: From a prospectively collected database between 2000 and 2019, patients undergoing laparoscopic repeat liver resections were classified according to the Institut Mutualiste Montsouris classification. Doubly robust estimators (weighted regressions) were used to assess the effect of factors on intra- and postoperative outcomes and allowed for strong adjustment on age, body mass index, American Society of Anesthesiologists, carcinoembryonic antigen, number, and size of lesions. Unexpected difficulty was defined as a composite indicator which included substantial blood loss and/or substantial operative time and/or conversion. RESULTS: Of 205 laparoscopic repeat liver resections patients, 87, 25, and 93 procedures were classified as grade 1, 2, and 3 laparoscopic repeat liver resections, respectively. After doubly robust adjustment, the IMM classification was associated with blood loss (Cohen f2 0.12; P = 0.001), operative time (Cohen f2 0.07; P = .001), and length of stay (Cohen f2 0.13; P = .001), as well as with the risk of both minor and severe complications (odd ratio = 2.94; 95% confidence interval: 2.06-4.20) and the chances of achieving textbook outcome (relative risk = 0.57; 95% confidence interval: 0.41-0.81). Independently from the Institut Mutualiste Montsouris classification, a first major hepatectomy (relative risk = 1.15, 95% confidence interval: 1.03-1.29) as well as sinusoidal obstruction syndrome (relative risk = 1.24, 95% confidence interval: 1.09-1.41) were independent risk factors of unexpected difficulty. A first major resection was associated with decreased chances of textbook outcome (relative risk = 0.53; 95% confidence interval: 0.33-0.85). CONCLUSION: The Institut Mutualiste Montsouris classification is a valuable difficulty scoring system for laparoscopic repeat liver resections procedures, while previous major resection and presence of sinusoidal obstruction syndrome are likely to jeopardize the outcomes.

The Riemannian spatial pattern method: mapping and clustering movement imagery using Riemannian geometry.

Objective. Over the last decade, Riemannian geometry has shown promising results for motor imagery classification. However, extracting the underlying spatial features is not as straightforward as for applying common spatial pattern (CSP) filtering prior to classification. In this article, we propose a simple way to extract the spatial patterns obtained from Riemannian classification: the Riemannian spatial pattern (RSP) method, which is based on the backward channel selection procedure.Approach. The RSP method was compared to the CSP approach on ECoG data obtained from a quadriplegic patient while performing imagined movements of arm articulations and fingers.Main results.Similar results were found between the RSP and CSP methods for mapping each motor imagery task with activations following the classical somatotopic organization. Clustering obtained by pairwise comparisons of imagined motor movements however, revealed higher differentiation for the RSP method compared to the CSP approach. Importantly, the RSP approach could provide a precise comparison of the imagined finger flexions which added supplementary information to the mapping results.Significance.Our new RSP method illustrates the interest of the Riemannian framework in the spatial domain and as such offers new avenues for the neuroimaging community. This study is part of an ongoing clinical trial registered with ClinicalTrials.gov, NCT02550522.

Preoperative assessment of patient comorbidities before left colectomy: Comparison between ASA performance status scale and a new computed tomography physical status score.

PURPOSE: To compare a newly developed preoperative computed tomography physical status (CT-PS) score with the American Society of Anesthesiology performance status (ASA-PS) scale in the assessment of patient preoperative health status and stratification of perioperative risk before left colectomy. MATERIALS AND METHODS: Preoperative chest-abdomen-pelvis CT examinations of patients who were scheduled to undergo elective laparoscopic left colonic resection for cancer in two centers were reviewed by two radiologists blinded to clinical data for the presence of several key imaging features in order to assess general, cardiac, pulmonary, abdominal, renal, vascular and musculoskeletal status. CT examinations of patients from center 1 were used to build a CT-PS score to predict ASA-PS≥III. CT-PS score was further validated using an external cohort of patients from center 2. RESULTS: During a 2-year period, 117 consecutive patients (63 men, 54 women; mean age, 65±13 [SD] years; age range: 53-90 years) who underwent laparoscopic left colectomy for cancer in center 1 (66 patients, building cohort) and center 2 (51 patients, validation cohort) were retrospectively included. Ninety-one percent of patients were ASA-PS 1-2. Overall postoperative morbidity was 23% and severe morbidity 12%. The area under the receiver operating characteristic curve of CT-PS score was 0.968 (95% CI: 0.901-1.000) in the building cohort and 0.828 (95% CI: 0.693-0.963) in the validation cohort. The optimal thresholds yielded 87% (95% CI: 83-91%) sensitivity and 100% (95% CI: 91-100%) specificity in the building cohort and 75% (95% CI: 69-81%) sensitivity and 83% (95% CI: 77-88%) specificity in the validation cohort for the prediction of ASA-PS. CONCLUSION: Preoperative chest-abdomen-pelvis CT thoroughly and wisely read is highly accurate to differentiate patients with ASA-PS I/II from those with ASA-PS III/IV before left colectomy.

Unannounced Meal Detection for Artificial Pancreas Systems Using Extended Isolation Forest.

This study aims at developing an unannounced meal detection method for artificial pancreas, based on a recent extension of Isolation Forest. The proposed method makes use of features accounting for individual Continuous Glucose Monitoring (CGM) profiles and benefits from a two-threshold decision rule detection. The advantage of using Extended Isolation Forest (EIF) instead of the standard one is supported by experiments on data from virtual diabetic patients, showing good detection accuracy with acceptable detection delays.

Relevance of blood loss as key indicator of the quality of surgical care in laparoscopic liver resection for colorectal liver metastases.

BACKGROUND: The development of laparoscopic liver resection has led to the hypothesis that intraoperative blood loss may be a key indicator of surgical care quality. This study assessed short- and long-term results of patients according to three levels of intraoperative blood loss during laparoscopic liver resection for colorectal liver metastasis. METHODS: All patients who underwent laparoscopic liver resection for colorectal liver metastasis between 2000 and 2018 were included. Difficulty of laparoscopic liver resection was defined according to the Institut Mutualiste Montsouris classification. Three levels of the extent of intraoperative blood loss were defined: massive (≥1,000 mL), substantial (≥75th percentile of intraoperative blood loss within each grade of difficulty), and normal intraoperative blood loss. RESULTS: During study period, 317 patients underwent laparoscopic liver resection for colorectal liver metastasis. Among them, 213 (67.2%), 80 (25.2%), and 24 (7.6%) patients had normal, substantial, and massive intraoperative blood loss, respectively. Twenty-six patients (8.2%) required transfusion. Massive intraoperative blood loss came from a major hepatic vein in 54% of cases and were managed by laparoscopy in 83% of the cases. Laparoscopic liver resection difficulty grade (odds ratio = 3.15; P = .053) and number of colorectal liver metastasis (odds ratio = 1.24; P = .020) were independently associated with massive intraoperative blood loss. Risks factors for substantial intraoperative blood loss were bi-lobar colorectal liver metastasis (odds ratio = 3.12; P = .033) and sinusoidal obstruction syndrome (odds ratio = 3.27; P = .004). The level of intraoperative blood loss was not associated with severe complications nor overall and disease-free survival. Requirement of transfusion was associated with severe complications (odds ratio = 7.27; P = .002) and decreased 1-, 3-, and 5-year overall survival (87%, 68%, and 61% vs 95%, 88%, and 79%; P = .042). CONCLUSION: The extent of intraoperative blood loss did not affect short- and long-term results of laparoscopic liver resection for colorectal liver metastasis. Massive intraoperative blood loss was often incidental and, 83% of the time, manageable by laparoscopy. Rather than intraoperative blood loss, transfusion is a better relevant indicator of laparoscopic liver resection surgical quality.

A decade in the battlefield (2004-2014): A French military perspective on the high mortality associated with non-exclusively orthopedic or brain combat injuries.

BACKGROUND: During the last few decades, French armed forces have regularly deployed in asymmetric conflicts. Surgical support for casualties of these conflicts occurs in NATO role 2 and 3 medical treatment facilities (MTF); definitive surgical care occurs in France following a strategic medical evacuation. The aim of this study was to describe the combat injury profile of these soldiers who presented with either non-exclusively orthopedic and/or brain injuries. METHODS: This descriptive study is a retrospective analysis of the surgical management of French casualties performed in role 2 or 3 MTF in Afghanistan, Mali, Niger, Djibouti and the Central African Republic between January 2004 and December 2014. RESULTS: One hundred patients were included. Forty had fragment wounds. The most severe lesions were of the head, neck or thorax. The average injury severity score (ISS) was 34.9 (IC 95% 29.8-40). 17 damage control procedures were performed. Thirty patients died with a mean ISS of 61 (IC 95% 56-67); 5 deaths were considered as preventable. The most frequent surgical procedures in the MTF were digestive (n=31) and thoracic surgery (n=19). Thirty patients needed second-look surgery in France; eleven had severe complications. No patient died following medical evacuation to France. CONCLUSIONS: Results from this study indicated that the mortality following non-exclusively brain or orthopedic injuries remains high in modern asymmetric conflicts. Level of Evidence IV.

French civilian surgical expertise still inadequately prepared for mass casualties 3 years after major terror attacks in Paris (2015) and Nice (2016).

BACKGROUND: Three years after the terror attacks in Paris and Nice, this study aims to determine the level of interest, the technical skills and level of surgical activity in exsanguinating trauma care for a nonselected population of practicing French surgeons. METHODS: A questionnaire was sent between July and December 2017 to French students and practicing surgeons, using the French Surgical Colleges' mailing lists. Items analyzed included education, training, interest and clinical activity in trauma care and damage-control surgery (DCS). RESULTS: 622 questionnaires were analyzed and was composed of 318 (51%) certificated surgeons, of whom 56% worked in university teaching hospitals and 47% in Level I trauma centers (TC1); 44% were digestive surgeons and 7% were military surgeons. The mean score of 'interest in trauma care' was 8/10. Factors associated with a higher score were being a resident doctor (p = 0.01), a digestive surgeon (p = 0.0013), in the military (p = 1,71 × 10) and working in TC1 (p = 0.034). The mean "DCS techniques knowledge" score was 6.2/10 and factors significantly associated with a higher score were being a digestive surgeon (respectively, p = 0.0007 and p = 0.001) and in the military (respectively p = 1.74 × 10 and p = 3.94 × 10). Reported clinical activity in trauma and DCS were low. Additional continuing surgical education courses in trauma were completed by 23% of surgeons. CONCLUSION: French surgeons surveyed showed considerable interest in trauma care and treatment. Despite this, and regardless of surgical speciality, their theoretical and practical knowledge of necessary DCS skills remain inadequate. LEVEL OF EVIDENCE: Level III, Study Type Survey.

Glycemic variability indices can be used to diagnose islet transplantation success in type 1 diabetic patients.

AIMS: High glycemic variability (GV) is the major indication for islet transplantation (IT) in patients with type 1 diabetes (T1D). The actual criteria used to assess graft function do not consider GV improvement. Our study aimed to describe GV indices' evolution in T1D patients who benefited from IT during the TRIMECO trial and to evaluate if thresholds might be defined to diagnose IT success. METHODS: We collected data from 29 patients of the TRIMECO trial, a clinical trial (NCT01148680) comparing the metabolic efficacy of IT with intensive insulin therapy. Based on CGM data, we analyzed mean glucose level and four GV indices (standard deviation, coefficient of variation, MAGE and GVP) before (M0) and 6 months (M6) after IT. RESULTS: Each GV index decreased significantly between M0 and M6: SD 53.9 mg/dL [44.6-61.5] versus 20.1 mg/dL [13.5-24.3]; CV 35.2% [30.6-37.7] versus 17.3% [12.0-20.5]; MAGE 134.9 mg/dl [111.2-155.8] versus 51.9 mg/dL [32.4-62.4]; GVP 35.3% [24.9-47.2] versus 12.2% [6.2-18.8] (p ≤ 0.0001). Thresholds diagnosing IT success at 6 months post-transplant were an SD at 22.76 mg/dL (sensibility 88.89%, specificity 80.00%), a CV at 17.47% (sensibility 88.89%, specificity 70.00%), a MAGE at 54.81 mg/dL (sensibility 88.89%, specificity 80.00%) and a GVP at 12.27% (sensibility 88.89%, specificity 70.00%). CONCLUSIONS: This study confirms a positive impact of IT on GV. The proposed thresholds allow an easy evaluation of IT success using only CGM data and may be a clinical tool for the follow-up of transplanted patients.

Characterization of Daily Glycemic Variability in Subjects with Type 1 Diabetes Using a Mixture of Metrics.

Background: Glycemic variability (GV) is an important component of glycemic control for patients with type 1 diabetes (T1D). The inadequacy of existing measurements lies in the fact that they view the variability from different aspects, so that no consensus has been reached among physicians as to which metrics to use in practice. Moreover, although GV, from 1 day to another, can show very different patterns, few metrics have been dedicated to daily evaluations. Materials and Methods: A reference (stable glycemia) statistical model is built based on a combination of daily computed canonical glycemic control metrics including variability. The metrics are computed for subjects from the TRIMECO islet transplantation trial, selected when their ß-score (composite score for grading success) is ≥6 after a transplantation. Then, for any new daily glycemia recording, its likelihood with respect to this reference model provides a multimetric score of daily GV severity. In addition, determining the likelihood value that best separates the daily glycemia with ß-score = 0 from that with ß-score ≥6, we propose an objective decision rule to classify daily glycemia into "stable" or "unstable." Results: The proposed characterization framework integrates multiple standard metrics and provides a comprehensive daily GV index, based on which, long-term variability evaluations and investigations on the implicit link between variability and ß-score can be carried out. Evaluation, in a daily GV classification task, shows that the proposed method is highly concordant to the experience of diabetologists. Conclusion: A multivariate statistical model is proposed to characterize the daily GV of subjects with T1D. The model has the advantage to provide a single variability score that gathers the information power of a number of canonical scores, too partial to be used individually. A reliable decision rule to classify daily variability measurements into stable or unstable is also provided.

Landscape dynamics revealed by luminescence signals of feldspars from fluvial terraces.

Luminescence signals of quartz and feldspar minerals are widely used to determine the burial age of Quaternary sediments. Although luminescence signals bleach rapidly with sunlight exposure, incomplete bleaching may affect luminescence ages, in particular in fluvial settings where an unbleached remnant signal is commonly encountered in modern alluvium. Here, we use feldspar single-grain post-infrared IR stimulation (pIRIR) dating to show that recent (<11 ka) fluvial terraces of the Rangitikei River (New Zealand) were formed in a context of non-linear incision rate. We relate this pattern to the rapid reinstatement of steady-state incision following the formation of a major, climate-driven, aggradation terrace, causing a phase of accelerated incision. In addition, we show systematic variations in the proportion of unbleached grains in the fluvial sediments over time, mirroring incision rate at the time of deposition. Deposits formed during rapid incision contain fewer bleached grains, which we attribute to large input of unbleached material and limited bleaching opportunities during fluvial transport. This finding demonstrates that the luminescence signals recorded in fluvial terraces not only yield age information, but also inform us on past fluvial transport and ultimately, landscape dynamics.

Adrenalectomy for incidentaloma: lessons learned from a single-centre series of 274 patients.

BACKGROUND: Adrenal incidentalomas are increasingly diagnosed and include a wide spectrum of lesions from benign adenomas to secreting or malignant lesions. The aim of the present study is to report a large single-institution experience of patients undergoing surgery for adrenal incidentaloma with particular attention to their diagnosis and post-operative course and the evolution of surgical practice over time. METHODS: From 1993 to 2013, 274 patients underwent adrenalectomy for incidentaloma. All patients underwent standardized clinical, hormonal and imaging assessments. RESULTS: Patients were mainly female (63.1%; n = 173), and the median age of patients was 56.5 years. After a complete hormonal evaluation, 47.9% (n = 129) of incidentalomas were classified as secreting tumours, including 24.4% (n = 67) subclinical cortisol-secreting adenomas and 18.9% (n = 52) pheochromocytomas. Adrenocortical carcinomas represented 9.5% (n = 26) of incidentalomas, and the risk of malignancy was significantly correlated with tumour size. The conversion rate after laparoscopic adrenalectomy (90.9%; n = 249) was 3.2% (n = 8). The overall morbidity rate was 13.9%, which included a 4.4% rate of severe morbidity (Clavien-Dindo ≥3). From 2008 onwards, there was a significant decrease (P < 0.001) in the use of surgical approaches for non-secreting adenomas. CONCLUSION: After a complete work-up, half of the incidentalomas were classified as subclinical oversecreting adrenal lesions and 10% proved to be malignant adrenocortical carcinomas. The debatable use of surgical approaches for benign nonfunctioning adenomas significantly decreased over time.