High-Fat Ketogenic Diets and Physical Performance: A Systematic Review

ABSTRACT Use of high-fat, ketogenic diets (KDs) to support physical performance has grown in popularity over recent years. While these diets enhance fat and reduce carbohydrate oxidation during exercise, the impact of a KD on physical performance remains controversial. The objective of this work was to assess the effect of KDs on physical performance compared with mixed macronutrient diets [control (CON)]. A systematic review of the literature was conducted using PubMed and Cochrane Library databases. Randomized and nonrandomized studies were included if participants were healthy (free of chronic disease), nonobese [BMI (kg/m2) <30], trained or untrained men or women consuming KD (<50 g carbohydrate/d or serum or whole-blood β-hydroxybutyrate >0.5 mmol/L) compared with CON (fat, 12–38% of total energy intake) diets for ≥14 d, followed by a physical performance test. Seventeen studies (10 parallel, 7 crossover) with 29 performance (13 endurance, 16 power or strength) outcomes were identified. Of the 13 endurance-type performance outcomes, 3 (1 time trial, 2 time-to-exhaustion) reported lower and 10 (4 time trials, 6 time-to-exhaustion) reported no difference in performance between the KD compared with CON. Of the 16 power or strength performance outcomes, 3 (1 power, 2 strength) reported lower, 11 (4 power, 7 strength) no difference, and 2 (power) enhanced performance in the KD compared with the CON. Risk of bias identified some concern of bias primarily due to studies allowing participants to self-select diet intervention groups and the inability to blind participants to the study intervention. Overall, the majority of null results across studies suggest that a KD does not have a positive or negative impact on physical performance compared with a CON diet. However, discordant results between studies may be due to multiple factors, such as the duration consuming study diets, training status, performance test, and sex differences, which will be discussed in this systematic review.

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Utility of Ketone Supplementation to Enhance Physical Performance: A Systematic Review

Advances in Nutrition ◽

10.1093/advances/nmz104 ◽

2019 ◽

Cited By ~ 3

Author(s):

Lee M Margolis ◽

Kevin S O'Fallon

Keyword(s):

Systematic Review ◽

Physical Performance ◽

Ketone Bodies ◽

Endurance Performance ◽

Performance Outcomes ◽

Sufficient Evidence ◽

Lower Body ◽

Negative Effects ◽

The Impact ◽

Lower Body Power

ABSTRACT Ingesting exogenous ketone bodies has been touted as producing ergogenic effects by altering substrate metabolism; however, research findings from recent studies appear inconsistent. This systematic review aimed to aggregate data from the current literature to examine the impact of consuming ketone supplements on enhancing physical performance. A systematic search was performed for randomized controlled trials that measured physical performance outcomes in response to ingesting exogenous ketone supplements compared with a control (nutritive or non-nutritive) in humans. A total of 161 articles were screened. Data were extracted from 10 eligible studies (112 participants; 109 men, 3 women ) containing 16 performance outcomes [lower-body power (n = 8) and endurance performance (n = 8)]. Ketone supplements were grouped as ketone esters (n = 8) or ketone salts/precursors (n = 8). Of the 16 performance outcomes identified by the systematic review, 3 reported positive, 10 reported null, and 3 reported negative effects of ketone supplementation on physical performance compared with controls. Heterogeneity was detected for lower-body power ( Q = 40, I2 = 83%, P < 0.01) and endurance performance (Q = 95, I2 = 93%, P < 0.01) between studies. Similarly high levels of heterogeneity were detected in studies providing ketone esters (Q = 111, I2 = 93%, P < 0.01), and to a lesser extent studies with ketone salts/precursors (Q = 25, I2 = 72%, P < 0.01). Heterogeneity across studies makes it difficult to conclude any benefit or detriment to consuming ketone supplements on physical performance. This systematic review discusses factors within individual studies that may contribute to discordant outcomes across investigations to elucidate if there is sufficient evidence to warrant recommendation of consuming exogenous ketone supplements to enhance physical performance.

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P92 Power dynamics in healthcare teams – a barrier to team effectiveness and patient safety: A systematic review

BJS Open ◽

10.1093/bjsopen/zrab032.091 ◽

2021 ◽

Vol 5 (Supplement_1) ◽

Author(s):

Emma Kearns ◽

Zuneera Khurshid ◽

Sabrina Anjara ◽

Aoife De Brún ◽

Brendan Rowan ◽

...

Keyword(s):

Systematic Review ◽

Patient Safety ◽

Team Effectiveness ◽

Negative Impact ◽

Cochrane Library ◽

Power Dynamics ◽

Team Communication ◽

Speaking Up ◽

Healthcare Teams ◽

The Impact

Abstract Introduction Hierarchies in healthcare teams are pervasive and widely acknowledged as impacting on working cultures. This review explores the impact of power dynamics in multidisciplinary healthcare teams on patient safety and team effectiveness. Methods A systematic review was conducted using five academic databases (PubMed, CINAHL, PsycInfo, Cochrane Library, Embase) between January 2010-2020. Potentially relevant articles were selected based on title and abstract review, followed by full text review, data extraction and data appraisal. Consistent with PRISMA guidelines, two researchers independently carried out all stages, from data screening to quality appraisal. A narrative synthesis was conducted. Results The databases searches yielded a total of 869 studies. 28 studies met the eligibility criteria and were included in the synthesis. Of these, 20 articles associated power dynamics with team effectiveness and 19 linked power dynamics to patient safety outcomes. Hierarchical power dynamics inhibit team communication and speaking up behaviours, which impacts team effectiveness and patient safety. Barriers to speaking up include workplace policies; respect for seniors’ experience; time pressures; feelings of intimidation and powerlessness; fears of reprisal and repercussions; perceived poor self-efficacy; lack of confidence and role clarity. Conclusion Hierarchies and power dynamics have a profoundly negative effect on patient safety and team effectiveness through their negative impact on communication and speaking up behaviours. Whilst hierarchies cannot be abolished, to improve team communication and collaboration, healthcare organisations and training programmes should consider initiatives that break down silos and promote an inclusive approach to patient care. Initiatives that target the practice of collective leadership and an open and supportive work environment have been shown to improve communication and team effectiveness. Theme: Cross-disciplinary research

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The impact of exogenous nitric oxide during cardiopulmonary bypass for cardiac surgery

Perfusion ◽

10.1177/02676591211014821 ◽

2021 ◽

pp. 026765912110148

Author(s):

Joseph Mc Loughlin ◽

Lorraine Browne ◽

John Hinchion

Keyword(s):

Nitric Oxide ◽

Systematic Review ◽

Cardiac Surgery ◽

Cardiopulmonary Bypass ◽

Troponin I ◽

Length Of Hospital Stay ◽

Cochrane Library ◽

High Quality Research ◽

Low Cardiac Output Syndrome ◽

The Impact

Objectives: Cardiac surgery using cardiopulmonary bypass frequently provokes a systemic inflammatory response syndrome. This can lead to the development of low cardiac output syndrome (LCOS). Both of these can affect morbidity and mortality. This study is a systematic review of the impact of gaseous nitric oxide (gNO), delivered via the cardiopulmonary bypass (CPB) circuit during cardiac surgery, on post-operative outcomes. It aims to summarise the evidence available, to assess the effectiveness of gNO via the CPB circuit on outcomes, and highlight areas of further research needed to develop this hypothesis. Methods: A comprehensive search of Pubmed, Embase, Web of Science and the Cochrane Library was performed in May 2020. Only randomised control trials (RCTs) were considered. Results: Three studies were identified with a total of 274 patients. There was variation in the outcomes measures used across the studies. These studies demonstrate there is evidence that this intervention may contribute towards cardioprotection. Significant reductions in cardiac troponin I (cTnI) levels and lower vasoactive inotrope scores were seen in intervention groups. A high degree of heterogeneity between the studies exists. Meta-analysis of the duration of mechanical ventilation, length of ICU stay and length of hospital stay showed no significant differences. Conclusion: This systematic review explored the findings of three pilot RCTs. Overall the hypothesis that NO delivered via the CPB circuit can provide cardioprotection has been supported by this study. There remains a significant gap in the evidence, further high-quality research is required in both the adult and paediatric populations.

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Is the use of contraceptives associated with periodontal diseases? A systematic review and meta-analyses

BMC Women s Health ◽

10.1186/s12905-021-01180-0 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Micaele Maria Lopes Castro ◽

Maria Karolina Martins Ferreira ◽

Iasmin Encaua Essashika Prazeres ◽

Paula Beatriz de Oliveira Nunes ◽

Marcela Baraúna Magno ◽

...

Keyword(s):

Systematic Review ◽

Quantitative Analysis ◽

Periodontal Diseases ◽

Hormonal Contraceptive ◽

Cochrane Library ◽

Hormonal Contraceptives ◽

Clinical Parameters ◽

Significant Difference ◽

Meta Analyses ◽

The Impact

Abstract Background Previous studies indicated an impact of hormonal contraceptive use on oral health. This systematic review aimed to investigate the evidence supporting the impact of the use of hormonal contraceptives and periodontal diseases. Methods This study is based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and based on the PECO acrostic. Inclusion criteria comprised observational studies including women (P), which evaluated hormonal contraceptive users (E) and hormonal contraceptive non-users (C), to verify the association between this hormonal therapy and the periodontal diseases (O). Searches were performed on 5 databases: PubMed, Scopus, Web of Science, Cochrane Library, LILACS and grey literature (OpenGrey and Google Scholar). After the selection process, the included studies were evaluated qualitatively. Moreover, quantitative data were analyzed in two meta-analyses for clinical attachment loss (CAL) and probing depth (PD). Finally, the level of certainty was measured with the GRADE (Grading of Recommendations Assessment, Development, and Evaluation) tool between periodontal clinical parameters. Results 18 articles were eligible for the qualitative synthesis and 7 of them were selected for quantitative analysis. Hence, 15 of the eligible articles reported an association between the use of hormonal contraceptives and severity of periodontal disease. However, 6 articles demonstrated high risk of bias and were excluded from quantitative synthesis. The meta-analysis showed a statistically significant difference for CAL (MD 0.24 [0.09, 0.40]; p = 0.002), but in PD (MD 0.05 [− 0.05, 0.15]; p = 0.33) such difference was not identified. A very low level of evidence was found between the clinical parameters. Conclusions The use of hormonal contraceptives may be associated to severity of periodontal diseases. However, the quantitative analysis points to an inconclusive outcome due to the high level of heterogeneity. The association is biologically plausible, however additional studies are warranted to better elucidate the clinical significance of this possible association.

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Impact of Treatment for Nasal Cavity Disorders on Sleep Quality: Systematic Review and Meta-analysis

Otolaryngology ◽

10.1177/01945998211029527 ◽

2021 ◽

pp. 019459982110295

Author(s):

Jacob Fried ◽

Erick Yuen ◽

Kathy Zhang ◽

Andraia Li ◽

Nicholas R. Rowan ◽

...

Keyword(s):

Systematic Review ◽

Sleep Quality ◽

Nasal Obstruction ◽

Meta Analysis ◽

Mean Difference ◽

Cochrane Library ◽

Life Questionnaire ◽

Subjective Sleep Quality ◽

Subjective Sleep ◽

The Impact

Objective To determine the impact of treatment for patients with nasal obstruction secondary to allergic rhinitis (AR) and nasal septal deviation (NSD) on sleep quality. Data Sources Primary studies were identified though PubMed, Scopus, Cochrane Library, and Web of Science. Review Methods A systematic review was performed by querying databases for articles published through August 2020. Studies were included that reported on objective sleep parameters (apnea-hypopnea index) and sinonasal and sleep-specific patient-reported outcome measures: Rhinoconjunctivitis Quality of Life Questionnaire, Nasal Obstruction Symptom Evaluation, Epworth Sleepiness Scale (EpSS), and Pittsburgh Sleep Quality Index (PSQI). Results The database search yielded 1414 unique articles, of which 28 AR and 7 NSD studies were utilized for meta-analysis. A total of 9037 patients (8515 with AR, 522 with NSD) were identified with a mean age of 35.0 years (35.3 for AR, 34.0 for NSD). Treatment for AR and NSD significantly improved subjective sleep quality. For AR, the EpSS mean difference was −1.5 (95% CI, –2.4 to –0.5; P = .002) and for the PSQI, –1.7 (95% CI, –2.1 to –1.2; P < .00001). For NSD, the EpSS mean difference was −3.2 (95% CI, –4.2 to –2.2; P < .00001) and for the PSQI, –3.4 (95% CI, –6.1 to –0.6; P = .02). Conclusion Subjective sleep quality significantly improved following treatment for AR and NSD. There were insufficient data to demonstrate that objective metrics of sleep quality similarly improved.

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Efficacy of hydrofibre dressing following total joint arthroplasty: a meta-analysis of randomised controlled trials

Hip International ◽

10.1177/11207000211012669 ◽

2021 ◽

pp. 112070002110126

Author(s):

Raman Mundi ◽

Harman Chaudhry ◽

Seper Ekhtiari ◽

Prabjit Ajrawat ◽

Daniel M Tushinski ◽

...

Keyword(s):

Systematic Review ◽

Total Joint Arthroplasty ◽

Meta Analysis ◽

Joint Infection ◽

The United States ◽

Joint Arthroplasty ◽

Cochrane Library ◽

Controlled Trials ◽

Observable Effect ◽

The Impact

Introduction: In the United States, over 1,000,000 total joint arthroplasty (TJA) surgeries are performed annually and has been forecasted that this number will exceed 4,000,000 by the year 2030. Many different types of dressing exist for use in TJA surgery, and it is unclear if any of the newer, hydrofibre dressings are superior to traditional dressings at reducing rates of infections or improving wound healing. Thus, the aim of this systematic review and meta-analysis was to assess the impact of hydrofiber dressings on reducing complications. Methods: A systematic review and meta-analysis was performed using the online databases MEDLINE and the Cochrane Library. Randomized controlled trials (RCTs) comparing hydrofibre dressings to a standard dressing were included. Summary measures are reported as odds ratios (ORs) and mean differences (MDs) with 95% confidence intervals (CIs). Our primary outcome was prosthetic joint infection (PJI). Secondary outcomes included blisters, dressing changes and wound irritation. Results: 5 RCTs were included. Hydrofibre dressing had no observable effect on PJI or wound irritation (OR 0.53; 95% CI, 0.14–1.98; p = 0.35). Hydrofibre dressings reduced the rate of blisters (OR 0.36; 95% CI, 0.14–0.90; p = 0.03) and number of dressing changes (MD -1.89; 95% CI, -2.68 to -1.11). Conclusions: In conclusion, evidence suggests hydrofibre dressings have no observable effect on PJI and wound irritation. Evidence for reduction in blisters and number of dressings is modest given wide CIs and biased trial methodologies. Use of hydrofibre dressings should be considered inconclusive for mitigating major complications in light of current best evidence.

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Body composition changes in physically active individuals consuming ketogenic diets: a systematic review

Journal of the International Society of Sports Nutrition ◽

10.1186/s12970-021-00440-6 ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Julie L. Coleman ◽

Christopher T. Carrigan ◽

Lee M. Margolis

Keyword(s):

Systematic Review ◽

Body Composition ◽

Body Mass ◽

Risk Of Bias ◽

Fat Free Mass ◽

Cochrane Library ◽

Ideal Strength ◽

Physically Active ◽

Ketogenic Diets ◽

Study Intervention

Abstract Background To achieve ideal strength/power to mass ratio, athletes may attempt to lower body mass through reductions in fat mass (FM), while maintaining or increasing fat-free mass (FFM) by manipulating their training regimens and diets. Emerging evidence suggests that consumption of high-fat, ketogenic diets (KD) may be advantageous for reducing body mass and FM, while retaining FFM. Methods A systematic review of the literature was conducted using PubMed and Cochrane Library databases to compare the effects of KD versus control diets (CON) on body mass and composition in physically active populations. Randomized and non-randomized studies were included if participants were healthy (free of chronic disease), physically active men or women age ≥ 18 years consuming KD (< 50 g carbohydrate/d or serum or whole blood β-hydroxybutyrate (βhb) > 0.5 mmol/L) for ≥14 days. Results Thirteen studies (9 parallel and 4 crossover/longitudinal) that met the inclusion criteria were identified. Aggregated results from the 13 identified studies show body mass decreased 2.7 kg in KD and increased 0.3 kg in CON. FM decreased by 2.3 kg in KD and 0.3 kg in CON. FFM decreased by 0.3 kg in KD and increased 0.7 kg in CON. Estimated energy balance based on changes in body composition was − 339 kcal/d in KD and 5 kcal/d in CON. Risk of bias identified some concern of bias primarily due to studies which allowed participants to self-select diet intervention groups, as well as inability to blind participants to the study intervention, and/or longitudinal study design. Conclusion KD can promote mobilization of fat stores to reduce FM while retaining FFM. However, there is variance in results of FFM across studies and some risk-of-bias in the current literature that is discussed in this systematic review.

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Physical and functional performance assessment in pediatric oncology: a systematic review

Pediatric Research ◽

10.1038/s41390-021-01523-5 ◽

2021 ◽

Author(s):

Regine Söntgerath ◽

Julia Däggelmann ◽

Sabine V. Kesting ◽

Corina S. Rueegg ◽

Torge-Christian Wittke ◽

...

Keyword(s):

Systematic Review ◽

Muscle Strength ◽

Physical Performance ◽

Cardiorespiratory Fitness ◽

Pediatric Cancer ◽

Motor Performance ◽

Performance Test ◽

Functional Mobility ◽

Cancer Type ◽

And Function

Abstract Background Research indicates reduced physical performance from diagnosis into survivorship of pediatric cancer patients. However, there is no systematic information or guideline available on the methods to assess physical performance and function in this population. The purpose was to systematically compile and describe assessments of physical performance and function in patients and survivors of pediatric cancer, including cardiorespiratory fitness, muscle strength, speed, balance, flexibility, functional mobility, gait and motor performance test batteries. Methods We searched the databases PubMed, SPORTDiscus, and Cochrane Database and performed abstract and full-text selection of 2619 articles according to the Cochrane Handbook of Systematic Reviews. Information on patients characteristics, assessments, information on validity and reliability, and relevant references was extracted. Results In summary, 63 different assessments were found in 149 studies including 11639 participants. Most studies evaluated cardiorespiratory fitness and muscle strength with the majority conducted off treatment. Some outcomes (e.g. speed) and diagnoses (e.g. neuroblastoma) were severely underrepresented. With the exception of gait, leukemia patients represented the largest group of individuals tested. Conclusions Insufficient data and patient heterogeneity complicate uniform recommendations for assessments. Our results support researchers and practitioners in selecting appropriate assessment to meet their specific research questions or individual daily practice needs. Impact This systematic review includes 149 studies and provides a comprehensive summary of 63 assessments to evaluate cardiorespiratory fitness, muscle strength, speed, balance, flexibility, functional mobility, gait or motor performance test batteries in patients and survivors of pediatric cancer. We present the most studied fields within the pediatric cancer population, which are cardiorespiratory fitness and muscle strength, off treatment phase, and leukemia patients. We propose research priorities by identification of subgroups in terms of cancer type, phase of treatment, and outcome of interest that are underrepresented in studies currently available.

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The Use of Seton as a Bridge to Definitive Ligation of the Intersphincteric Fistula Tract Procedure for Fistula-in-ano: A Systematic Review and Meta-analysis

Journal of Coloproctology ◽

10.1055/s-0041-1730039 ◽

2021 ◽

Author(s):

Carlos Placer-Galán ◽

Jose Mª Enriquez-Navascués ◽

Tania Pastor-Bonel ◽

Ignacio Aguirre-Allende ◽

Yolanda Saralegui-Ansorena

Keyword(s):

Systematic Review ◽

Anal Fistula ◽

Meta Analysis ◽

Fistula Tract ◽

Cochrane Library ◽

Fistula In Ano ◽

Intersphincteric Fistula ◽

The Impact ◽

Seton Placement ◽

Primary Healing

Abstract Background There is still controversy over the usefulness of seton placement prior to the ligation of the intersphincteric fistula tract (LIFT) surgery in the management of anal fistula. Objective To evaluate the impact of preoperative seton placement on the outcomes of LIFT surgery for the management of fistula-in-ano. Design systematic review and meta-analysis. Data Sources A search was performed on the MEDLINE (PubMed), EMBASE, Scopus, Web of Science, Cochrane Library and Google Scholar databases. Study Selection Original studies without language restriction reporting the primary healing rates with and without seton placement as a bridge to definitive LIFT surgery were included. Intervention The intervention assessed was the LIFT with and without prior seton placement. Main Outcome Measures The main outcome was defined as the primary healing rate with and without the use of seton as a bridge to definitive LIFT surgery. Results Ten studies met the criteria for systematic review, all retrospective, with a pooled study population of 772 patients. There were no significant differences in the percentages of recurrence between patients with and without seton placement (odds ratio [OR] 1.02; 95% confidence interval [CI] 0.73–1.43: p = 0.35). The I2 value was 9%, which shows the homogeneity of the results among the analyzed studies. The 10 included studies demonstrated a weighted average overall recurrence of 38% (interquartile range [IQR] 27–42.7%), recurrence with the use of seton was 40% (IQR 26.6–51.2%), and without its use, the recurrence rate was 51.3% (IQR 31.3–51.3%) Limitations The levels of evidence found in the available literature were relatively fair, as indicated after qualitative evaluation using the Newcastle-Ottawa scale and the Attitude Heading Reference System (AHRS) evidence levels. Conclusions Our meta-analysis suggests that the placement of seton as a bridge treatment prior to LIFT surgery does not significantly improve long-term anal fistula healing outcomes. Ligation of the intersphincteric fistula tract surgery can be performed safely and effectively with no previous seton placement.International prospective register of systematic reviews—PROSPERO registration number: CDR42020149173.

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Risk of nodal disease in patients with MRI-detected extramural vascular invasion in rectal cancer: a systematic review and meta-analysis

Tumori Journal ◽

10.1177/0300891620975867 ◽

2020 ◽

pp. 030089162097586

Author(s):

Pratik Tripathi ◽

Zhen Li ◽

Yaqi Shen ◽

Xuemei Hu ◽

Daoyu Hu

Keyword(s):

Systematic Review ◽

Rectal Cancer ◽

Lymph Node ◽

Vascular Invasion ◽

Literature Search ◽

Meta Analysis ◽

Adjuvant Chemoradiotherapy ◽

Cochrane Library ◽

Nodal Disease ◽

The Impact

Background: The impact of magnetic resonance imaging–detected extramural vascular invasion (mrEMVI) in distant metastasis is well known but its correlation with prevalence of lymph node metastasis is less studied. The aim of this systematic review and meta-analysis was to assess the prevalence of nodal disease in mrEMVI–positive and negative cases in rectal cancer. Methods: Following guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analyses, a systematic literature search in PubMed, Web of Science, Cochrane Library, and EMBase was carried out to identify relevant studies published up to May 2019. Results: Our literature search generated 10 studies (863 and 1212 mrEMVI–positive and negative patients, respectively). The two groups (mrEMVI–positive and negative) were significantly different in terms of nodal disease status (odds ratio [OR] 3.15; 95% confidence interval [CI] 2.12–4.67; p < 0.001). The prevalence of nodal disease was 75.90% vs 52.56% in the positive mrEMVI vs negative mrEMVI group, respectively ( p < 0.001). The prevalence of positive lymph node in positive mrEMVI patients treated with neoadjuvant/adjuvant chemoradiotherapy (nCRT/CRT) (OR 2.47; 95% CI 1.65–3.69; p < 0.001) was less compared with the patients who underwent surgery alone (OR 6.25; 95% CI 3.74–10.44; p < 0.001). Conclusion: The probability of positive lymph nodes in cases of positive mrEMVI is distinctly greater compared with negative cases in rectal cancer. Positive mrEMVI indicates risk of nodal disease prevalence increased by threefold in rectal cancer.

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