Showing papers by "Martin Lames published in 2022"
TL;DR: The study demonstrated that transient elastography is a feasible tool to stratify clinically significant liver disease in community alcohol services and can stimulate a change in high-risk drinking behaviour and a normal liver stiffness result does not provide false reassurance to participants.
Abstract: Introduction: Alcohol is the leading cause of cirrhosis in Western populations. The early identification of high-risk drinkers followed by intervention is an effective way to reduce harm. We aim to assess the feasibility of integrating transient elastography (TE) into community alcohol services, and to determine its impact on modifying drinking behaviours. Method: A prospective cohort study was conducted at a community alcohol clinic in Nottingham, UK (April 2012 to March 2014). Patients (>18 years) with a primary alcohol problem were recruited. Those known to liver services or those known to have chronic liver disease were excluded. Significant liver fibrosis was defined by a liver stiffness of >8 kilopascal (kPa). Follow-up was for a minimum of six months. Data were descriptively analysed for significant differences between patients with a normal liver stiffness versus raised liver stiffness. Results: 156 patients were invited; n = 87 attended and n = 86 underwent successful TE. The majority were male (n = 53, 70.0%), and the mean age was 46.3 years (SD ± 9.8). Median liver stiffness was 6.9 kPa (range 3.1–75.0kPa). Clinically significant liver fibrosis was identified in n = 33 (38.4%), of which n = 6 were in the cirrhotic range (≥15 kPa). The baseline median self-reported alcohol intake for normal stiffness was 126 units per week (range 24–378) and in raised stiffness was 149.0 units per week (range 39.0–420.0); this difference was nonsignificant (p = 0.338). The median reduction in self-reported alcohol intake in the whole cohort was 65.0 units per week (range 27.0–88.0, p < 0.001); in the normal liver stiffness group it was 25.0 units per week (range 18.0–75.0, p = 0.154), and in the raised liver stiffness group it was 78.5 units per week (range 36.0–126.0, p < 0.001). Conclusion: The study demonstrated that transient elastography is a feasible tool to stratify clinically significant liver disease in community alcohol services. It can stimulate a change in high-risk drinking behaviour and a normal liver stiffness result does not provide false reassurance to participants.
3 citations
TL;DR: A high player availability rate was observed and no differences were observed in physical, physiological, and psychophysiological indices of performance when comparing shorter and longer time intervals between consecutive matches.
Abstract: This study aimed to analyse match availability, participation, and muscle injury incidence and to compare the effect of time intervals between matches (3-4 versus 6-7 days) on physical, physiological, and psychophysiological parameters in a professional football team during a prolonged congested fixture period. Thirteen professional male football players (29.2 ± 4.8 years old; 78.5 ± 8.3 kg; 179.3 ± 8.8 cm;) participated. Data were collected during 17 consecutive weeks for 35 official matches separated by an average interval of ≤ 3.5 days. Results showed a player availability of 84.8 ± 16.1% while match participation was 68.8% ± 6.4%. Muscle injury incidence was 19.0/ 1,000 hours of match exposure. These injuries occurred after individual players participated in sequences of 8.3 ± 3.3 consecutive matches with intervals of 3.8 ± 0.8 days. No differences were observed in physical performance or in fatigue-related parameters irrespective of the time interval between matches . a high player availability rate was observed. No differences were observed in physical, physiological, and psychophysiological indices of performance when comparing shorter and longer time intervals between consecutive matches.Prolonged exposure to fixture congestion resulted in an high risk of incurring muscle injury.
2 citations
TL;DR: It is concluded that drone-based position detection could serve as a promising alternative to existing EPTS but would benefit from further comparisons in dynamic settings and across different sports.
Abstract: Radio and video-based electronic performance and tracking systems (EPTS) for position detection are widely used in a variety of sports. In this paper, the authors introduce an innovative approach to video-based tracking that uses a single camera attached to a drone to capture an area of interest from a bird’s eye view. This pilot validation study showcases several applications of this novel approach for the analysis of game and racket sports. To this end, the authors compared positional data retrieved from video footage recorded using a drone with positional data obtained from established radio-based systems in three different setups: a tennis match during training with the drone hovering at a height of 27 m, a small-sided soccer game with the drone at a height of 50 m, and an Ultimate Frisbee match with the drone at a height of 85 m. For each type of playing surface, clay (tennis) and grass (soccer and Ultimate), the drone-based system demonstrated acceptable static accuracy with root mean square errors of 0.02 m (clay) and 0.15 m (grass). The total distance measured using the drone-based system showed an absolute difference of 2.78% in Ultimate and 2.36% in soccer, when compared to an established GPS system and an absolute difference of 2.68% in tennis, when compared to a state-of-the-art LPS. The overall ICC value for consistency was 0.998. Further applications of a drone-based EPTS and the collected positional data in the context of performance analysis are discussed. Based on the findings of this pilot validation study, we conclude that drone-based position detection could serve as a promising alternative to existing EPTS but would benefit from further comparisons in dynamic settings and across different sports.
1 citations
TL;DR: In this article , the authors investigated whether a tissue water content correction, as assessed by MRI relaxometry, could provide better agreement between MRI and visual estimates of fat fraction in fibrotic livers.
Abstract: Magnetic resonance spectroscopy (MRS) provides a powerful method of measuring fat fraction. However, previous studies have shown that MRS results give lower values compared with visual estimates from biopsies in fibrotic livers. This study investigated these discrepancies and considered whether a tissue water content correction, as assessed by MRI relaxometry, could provide better agreement.110 patients were scanned in a 1.5 T Philips scanner and biopsies were obtained. Multiple echo MRS (30 × 30 × 30 mm volume) was used to determine Proton Density Fat Fraction (PDFF). Biopsies were assessed by visual assessment for fibrosis and steatosis grading. Digital image analysis (DIA) was also used to quantify fat fraction within tissue samples. T1 relaxation times were then used to estimate tissue water content to correct PDFF for confounding factors.PDFF values across the four visually assessed steatosis grades were significantly less in the higher fibrosis group (F3-F4) compared to the lower fibrosis group (F0-F2). The slope of the linear regression of PDFF vs DIA fat fraction was ~ 1 in the low fibrosis group and 0.77 in the high fibrosis group. Correcting for water content based on T1 increased the gradient but it did not reach unity.In fibrotic livers, PDFF underestimated fat fraction compared to DIA methods. Values were improved by applying a water content correction, but fat fractions were still underestimated.
1 citations
16 Nov 2022
TL;DR: In this article , the authors investigated how national teams’ tournaments scheduled at such a time window impact the playing time of released players, using data from the Africa Cups of Nations (AFCON).
Abstract: Due to the unfavourable climatic conditions in Qatar during summertime, the FIFA World Cup 2022 will be played during on-going seasons of the major European leagues. This study investigates how national teams’ tournaments scheduled at such a time window impact the playing time of released players, using data from the Africa Cups of Nations (AFCON). For 262 internationals playing at the 2013, 2015 and 2021 AFCON, we compared the share of possible games and minutes played before and after the tournament using Mann-Whitney-U tests. We found a significant decrease of 3.3% for games (p=.029, CL EffectSize =44.5%) and 3.1% for minutes played respectively (p=.018, CL EffectSize =44.9%). For a subsample of 163 players, which played for the same club the preceding seasons, we found that these players tend to have played more in the second half of the previous season, resulting in a net decrease of 6.8% for games (p=.011, CL EffectSize =42.3%) and 7.1% for minutes played (p=.007, CL EffectSize =41.9%). Conclusions for the FIFA World Cup 2022 should only be drawn carefully as the number of released players was comparatively low. However, the findings give some indication that releasing clubs might suffer the rest of the season after this tournament.
TL;DR: In this article , the authors used OpenPose to detect relevant body orientation angles from video data of penalty kicks in elite football and investigate the relationship between these body angles and observable behaviors analyzed via an observational system for penalty kick analysis in football.
Abstract: Body orientation of football players has proven to be an informative resource related to successful penalty kicks. OpenPose is one of the most popular open-source pose estimation technologies. This study aims: (i) to verify whether OpenPose can detect relevant body orientation angles from video data of penalty kicks in elite football and (ii) to investigate the relationship between these body angles and observable behaviors analyzed via an observational system for penalty kick analysis in football (OSPAF) with the penalty taker and goalkeeper strategy. A total of 34 penalty videos, with standardized viewing angle, from the main European leagues (2017–2020) were analyzed. Relevant body orientation variables were selected for penalty kicks analysis and were extracted from video data through OpenPose technique. The OSPAF, previously validated by experts, was used. The mean confidence score of OpenPose measures was 0.80 ± 0.14. The mean kappa value for repeated measurements of OpenPose was 0.96 ± 0.04. Logistic regressions were performed to investigate the relationship between OpenPose investigated variables (penalty taker: shoulder, hips, and nonkicking foot orientation; goalkeeper: right and left foot, anticipation), observable behaviors (OSPAF variables), and the strategy (penalty taker: goalkeeper dependent or independent; goalkeeper: shooter dependent or independent) in penalty kicks. The selected body orientation angle (goalkeeper anticipation) measured through OpenPose correlated significantly with the goalkeeper strategy. The prediction model of the goalkeeper's strategy had its accuracy increased to 97% when the variable goalkeeper anticipation was included [χ(35)2 = 49.648, p < 0.001]. Lower degrees of goalkeeper anticipation, the goalkeeper tactical action (awaiting), and run up speed (slow) were associated with a kicker-dependent strategy. Regarding the penalty taker, the selected body angles measured through OpenPose did not associate significantly with the shooter strategy. Body orientation analysis by using OpenPose has shown sufficient reliability and provides practical applications for analyzing the strategies adopted by goalkeepers in penalty kicks in elite football.
TL;DR: In this paper , the authors used finite Markov chains and the connected transition probabilities to evaluate game behavior in tennis and revealed insights in the current game structure of tennis, as well as the connected influence of the factors court surface and gender of players.
Abstract: Markov chains are a well-known tool in mathematical modelling. In performance analysis, finite Markov chains and the connected transition probabilities can be used to evaluate game behavior. Herein finite Markov chains are especially suited in the modelling of net games like tennis, due to their structure as an alternating sequence of discrete strokes. Finite Markov chain modelling thereby can be used as a descriptive tool, as well as to gain insight in the relationship between sports behavior and outcomes. The transition matrix can be used to display the frequency of game actions in relation to the respective game structure. Likewise, the model calculations from the theory of Markov chains enable determining the relevance of actions therein, concerning overall performance. To permit the usage of finite Markov chain modelling, adherence to the Markov property, often described as the property of “memorylessness”, must be assured. Present study implemented finite Markov chain modelling for elite level tennis at the Australian and French Open. The goal of the present study was to verify the usage of Markov chain modelling in tennis, using a newly designed transition matrix. Furthermore, the aim was to gain insight in the game structure of tennis. Results showed that the new model adhered to the Markov property in an extent, which allowed the usage of selected model predictions for the analysis. Further the analysis revealed insights in the current game structure of tennis, as well as connected influence of the factors court surface and gender of players.
01 Jan 2022
01 Jun 2022
TL;DR: In this paper , the feasibility of integrating transient elastography (TE) into community alcohol services and to determine its impact on modifying drinking behaviours was assessed in a prospective cohort study at a community alcohol clinic in Nottingham (April-2012 to March-2014).
Abstract:
Introduction
Alcohol is the leading cause of cirrhosis in western populations. Early identification of high-risk drinkers followed by intervention is an effective way to reduce harm. We aim to assess the feasibility of integrating transient elastography (TE) into community alcohol services and to determine its impact on modifying drinking behaviours.Method
A prospective cohort study was conducted at a community alcohol clinic in Nottingham (April-2012 to March-2014). Patients (>18years) with a primary alcohol problem were recruited. Those known to liver services or to have chronic liver disease were excluded. Significant liver fibrosis was defined by a liver stiffness measure (LSM) of >8 kilopascals (kPa). Follow-up was for a minimum of six months. Data were descriptively analysed for significant differences between patients with a normal LSM versus raised LSM.Results
156 patients were invited; n=87 attended and n=86 underwent successful TE. The majority were male (n=53, 70.0%) and the mean age was 46.3 years (SD +/-9.8). Median liver stiffness was 6.9kPa. Clinically significant liver fibrosis was identified in n=33 (38.4%), of which n=6 were in cirrhotic range (≥15 kPa). Baseline median self-reported alcohol intake for normal stiffness was 126 units per week and in raised stiffness was 149.0 units per week the difference was non-significant (p=0.338). Median reduction in self-report alcohol intake in whole cohort was 65.0 units per week (p=<0.001), in normal liver stiffness group was 25.0 units per week (p=0.154), and in raised liver stiffness group was 78.5 units per week (p<0.001).Conclusion
The study demonstrated that transient elastography is a feasible tool to stratify clinically significant liver disease in community alcohol services. It can stimulate a change in high-risk drinking behaviour and a normal liver stiffness result does not provide false reassurance to participants.TL;DR: In this paper , EUS-guided choledocho-duodenostomy is an option to relieve jaundice after a failed ERCP, in patients with locally advanced or metastatic peri-ampullary cancers.
Abstract:
EUS-guided choledocho-duodenostomy is an option to relieve jaundice after a failed ERCP, in patients with locally advanced or metastatic peri-ampullary cancers. We aim to assess the technical success, safety and outcomes of the procedure in our practice.
All consecutive adult patients that underwent EUS-guided CBD stent placement after a failed ERCP between December 2019 and May 2022 at the Queens Medical Centre, Nottingham were included. Studied variables included demographics, technical characteristics and outcomes including length of stay, normalisation of bilirubin level, complication rate and 30-day mortality rate.
Twenty-six consecutive patients were included in this study (12 males, 14 females). The mean age was 75 (range 52–92) years. Pancreatic cancer was present in 15 patients (57.6%), 4 patients (15.3%) each had ampullary cancer and other malignant peri-ampullary lesions while 3 patients (11.5%) had duodenal cancer. Metastatic disease was present in 13 patients (50%). Mean ECOG status was 2 (n= 13). ERCP was unsuccessful due to an inability to cannulate the CBD (n= 3), duodenal tumour infiltration (n=10), destroyed ampulla (n=6) and inaccessible papilla (n=5).
EUS-guided CBD stent placement was successful in 24 patients (92.3%). The mean CBD diameter at presentation was 19.5 mm (range 14–32) and mean distance between the bile duct and duodenum was 4.2 mm.
The complication rate was 15.3% (4/26 patients). Complications included cholecystitis, stent blockage, slow bleeding and bowel perforation after a displaced stent. Median post-procedure LOS was 5.5 days. A reduction in bilirubin to <50% was observed in 19 patients (73%) by discharge. There were 2 biliary re-interventions in the group. The overall 30-day mortality rate was 38.4% (n=10) with a procedure specific mortality of 11.5% (n=3).
EUS-guided choledocho-duodenostomy is an effective and safe option to relieve jaundice in this group of patients.