European Society of Coloproctology: Guidelines for diagnosis and treatment of cryptoglandular anal fistula.

AIM: The primary aim of the European Society of Coloproctology (ESCP) Guideline Development Group (GDG) was to produce high-quality, evidence-based guidelines for the management of cryptoglandular anal fistula with input from a multidisciplinary group and using transparent, reproducible methodology. METHODS: Previously published methodology in guideline development by the ESCP has been replicated in this project. The guideline development process followed the requirements of the AGREE-S tool kit. Six phases can be identified in the methodology. Phase one sets the scope of the guideline, which addresses the diagnostic and therapeutic management of perianal abscess and cryptoglandular anal fistula in adult patients presenting to secondary care. The target population for this guideline are healthcare practitioners in secondary care and patients interested in understanding the clinical evidence available for various surgical interventions for anal fistula. Phase two involved formulation of the GDG. The GDG consisted of 21 coloproctologists, three research fellows, a radiologist and a methodologist. Stakeholders were chosen for their clinical and academic involvement in the management of anal fistula as well as being representative of the geographical variation among the ESCP membership. Five patients were recruited from patient groups to review the draft guideline. These patients attended two virtual meetings to discuss the evidence and suggest amendments. In phase three, patient/population, intervention, comparison and outcomes questions were formulated by the GDG. The GDG ratified 250 questions and chose 45 for inclusion in the guideline. In phase four, critical and important outcomes were confirmed for inclusion. Important outcomes were pain and wound healing. Critical outcomes were fistula healing, fistula recurrence and incontinence. These outcomes formed part of the inclusion criteria for the literature search. In phase five, a literature search was performed of MEDLINE (Ovid), PubMed, Embase (Ovid) and the Cochrane Database of Systematic Reviews by eight teams of the GDG. Data were extracted and submitted for review by the GDG in a draft guideline. The most recent systematic reviews were prioritized for inclusion. Studies published since the most recent systematic review were included in our analysis by conducting a new meta-analysis using Review manager. In phase six, recommendations were formulated, using grading of recommendations, assessment, development, and evaluations, in three virtual meetings of the GDG. RESULTS: In seven sections covering the diagnostic and therapeutic management of perianal abscess and cryptoglandular anal fistula, there are 42 recommendations. CONCLUSION: This is an up-to-date international guideline on the management of cryptoglandular anal fistula using methodology prescribed by the AGREE enterprise.

Differential Incidence of Contrast-Associated Acute Kidney Injury: Comparing Intravenous and Intraarterial Contrast Administration.

PURPOSE OF THE REVIEW: Contrast-associated acute kidney injury (CA-AKI) remains a significant concern in diagnostic and invasive procedures, particularly in the context of iodinated contrast material administration. The traditional definition of CA-AKI, based on serum creatinine elevation following contrast exposure, may not accurately capture its multifactorial nature. RECENT FINDINGS: Studies have provided new insights into the differential incidence of CA-AKI between intravenous and intraarterial contrast administration, emphasizing the importance of tailored preventative strategies for high-risk procedures. This higher risk may arise from two proposed mechanisms: one implicating free radical formation leading to cytotoxicity and apoptosis in renal cells and another suggesting that contrast media alter renal hemodynamics, particularly in the outer medulla, by constricting the vasa recta and reducing medullary flow. Advances in technology and patient care, including contemporary use of low-osmolar contrast agents and hydration protocols, mitigate CA-AKI risk. Diagnostic and invasive procedures should not be avoided solely due to concerns about renal dysfunction if the patient is likely to benefit clinically.

Updates on Non-Statin LDL-Lowering Therapy.

PURPOSE OF REVIEW: There is ample evidence of the benefits and safety of low-density lipoprotein (LDL)-lowering therapies in the prevention of atherosclerotic cardiovascular disease. While statins remain the first-line agent for LDL reduction, several new therapies are now available. This narrative review provides an overview of currently available non-statin LDL-lowering agents, specifically mechanisms of action and data on efficacy and safety. It also discusses recommendations on their use in clinical practice. RECENT FINDINGS: Ezetimibe, PCSK9 inhibitors, and bempedoic acid have proven safe and efficacious in reducing cardiovascular events in large randomized controlled trials. Inclisiran is a promising agent that suppresses PCSK9 mRNA translation and is currently under investigation in a large clinical outcomes randomized controlled trial assessing its effect on clinical outcomes. Expert consensus advocates for lower LDL targets in higher risk patients and escalation to or a combination of non-statin therapies as needed to achieve these goals.

Temperature-dependent THz properties and emission of organic crystal BNA.

As high-average power ultrafast lasers become increasingly available for nonlinear conversion, the temperature dependence of the material properties of nonlinear crystals becomes increasingly relevant. Here, we present temperature-dependent THz complex refractive index measurements of the organic crystal BNA over a wide range of temperatures from 300 K down to 80 K for THz frequencies up to 4 THz for the first time. Our measurements show that whereas the temperature-dependent refractive index has only minor deviation from room temperature values, the temperature-dependent absorption coefficient decreases at low temperature (-24% from 300 K to 80 K). We additionally compare these measurements with conversion efficiency and spectra observed during THz generation experiments using the same crystal actively cooled in the same temperature range, using an ultrafast Yb-laser for excitation. Surprisingly, the damage threshold of the material does not improve significantly upon active cooling, pointing to a nonlinear absorption mechanism being responsible for damage. However, we observe a significant increase in THz yield (+23%) at lower temperatures, which is most likely due to the reduced THz absorption. These first findings will be useful for future designs of high-average power pumped organic-crystal based THz-TDS systems.

Protective ileostomy creation after anterior resection of the rectum: Shared decision-making or still subjective?

AIM: The choice of whether to perform protective ileostomy (PI) after anterior resection (AR) is mainly guided by risk factors (RFs) responsible for the development of anastomotic leakage (AL). However, clear guidelines about PI creation are still lacking in the literature and this is often decided according to the surgeon's preferences, experiences or feelings. This qualitative study aims to investigate, by an open-ended question survey, the individual surgeon's decision-making process regarding PI creation after elective AR. METHOD: Fifty four colorectal surgeons took part in an electronic survey to answer the questions and describe what usually led their decision to perform PI. A content analysis was used to code the answers. To classify answers, five dichotomous categories (In favour/Against PI, Listed/Unlisted RFs, Typical/Atypical, Emotions/Non-emotions, Personal experience/No personal experience) have been developed. RESULTS: Overall, 76% of surgeons were in favour of PI creation and 88% considered listed RFs in the question of whether to perform PI. Atypical answers were reported in 10% of cases. Emotions and personal experience influenced surgeons' decision-making process in 22% and 49% of cases, respectively. The most frequently considered RFs were the distance of the anastomosis from the anal verge (96%), neoadjuvant chemoradiotherapy (88%), a positive intraoperative leak test (65%), blood loss (37%) and immunosuppression therapy (35%). CONCLUSION: The indications to perform PI following rectal cancer surgery lack standardization and evidence-based guidelines are required to inform practice. Until then, expert opinion can be helpful to assist the decision-making process in patients who have undergone AR for adenocarcinoma.

Multicenter validation of the PREDICT score for prediction of local recurrence after total mesorectal excision of rectal cancer.

BACKGROUND: Total mesorectal excision (TME) is the gold standard treatment for rectal cancer. Although TME has managed to decrease the rates of local recurrence after rectal cancer resection, local recurrence is still recorded at varying rates. The present study aimed to validate the PREDICT score in the prediction of local recurrence of rectal cancer after TME with curative intent. METHODS: This was a retrospective multicenter study on patients with nonmetastatic low or middle rectal cancer who underwent TME. The total PREDICT score was calculated for every patient and related to the onset of local recurrence. According to the final score, patients were allocated to one of three risk groups: low, moderate, and high, and the rates of local recurrence in each group were calculated and compared. RESULTS: The present study included 262 patients (50.4% males) with a mean age of 47.1 years. The overall local recurrence rate was 12.6%. 29.4% of patients were in the low-risk group, 63.7% in the moderate-risk group, and 6.9% in the high-risk group. The local recurrence rate was 3.9% (95% confidence interval [CI]: 0.8-10.9) in the low-risk group, 13.2% (95% CI: 8.4-19.3) in the moderate risk group, and 44.4% (95% CI: 21.5-69.2) in the high-risk group (p < 0.0001). The sensitivity of the PREDICT score was 72.7%, the specificity was 88.1%, and the accuracy was 86.3%. CONCLUSIONS: The PREDICT score had good diagnostic accuracy in the prediction of local recurrence after TME and a good discriminatory ability in the differentiation between patients at different risks to develop local recurrence.

Efficacy and Safety of Non-Operative Management of Uncomplicated Acute Appendicitis Compared to Appendectomy: An Umbrella Review of Systematic Reviews and Meta-Analyses.

BACKGROUND: Non-operative management (NOM) of uncomplicated acute appendicitis (AA) has been introduced as an alternative to appendectomy. This umbrella review aimed to provide an overview of the efficacy and safety of NOM of uncomplicated AA in the published systematic reviews. METHODS: This umbrella review has been reported in line with the PRISMA guidelines and umbrella review approach. Systematic reviews with and without meta-analyses on the efficacy of NOM of AA were analyzed. The quality of the reviews was assessed with the AMSTAR 2 tool. The main outcomes measures were the treatment failure and complication rates of NOM and hospital stay as compared to appendectomy. RESULTS: Eighteen systematic reviews were included to this umbrella review. Eight reviews documented higher odds of failure with NOM, whereas two reviews revealed similar odds of failure. Six reviews reported lower odds of complications with NOM, six reported similar odds, and one reported lower odds of complications with surgery. Eight reviews reported similar hospital stay between NOM and appendectomy, one reported longer stay with NOM and another reported shorter stay with NOM. Pooled analyses showed that NOM was associated with higher treatment failure overall, in children-only, adults only, and RCTs-only meta-analyses. NOM was associated with lower complications overall, yet children-only and RCTs-only analyses revealed similar complications to surgery. NOM was associated with shorter stay in the overall and adult-only analysis, but not in the children-only analysis. CONCLUSIONS: NOM of AA is associated with higher treatment failure, marginally lower rate of complications and shorter stay than appendectomy.

Posterior component separation with transversus abdominis muscle release versus mesh-only repair in the treatment of complex ventral-wall hernia: a randomized controlled trial.

BACKGROUND: Complex ventral hernias (VHs) represent a real challenge to both general and plastic surgeons. This study aims to compare Sublay Mesh-Only Repair to Posterior Component Separation "PCS" with Transversus Abdominis Release "TAR" in the treatment of complex ventral-wall hernias (VHs). METHODS: This a randomized, controlled, intervention, including two parallel groups: A; Sublay Mesh-Only Repair and Group B; "TAR". Consecutive patients of both genders aged between 18 and 65 years old with complex VHs presented at Mansoura University Hospitals including large-sized abdominal-wall hernia ≥ 10 cm in width, loss of domain ≥ 20%, multiple hernial defects, or recurrent hernias. Immuno-compromised patients, patients with liver impairment, or severe heart failure were considered an exclusion criterion. The primary outcome is the recurrence rate after 12-months following the procedure. RESULTS: Fifty-six patients were recruited in this study. There was no significant difference between both groups regarding recurrence. However, there was significant differences between both groups regarding seroma favoring mesh-only repair. CONCLUSIONS: Although TAR may be associated with longer operative times and more blood losses, these were not found to be statistically significant. Postoperative complication, except for seroma, and recurrence rates were comparable in both groups. Trail registration The study was registered on clicaltrials.gov "NCT04516031".

Milliwatt average power, MHz-repetition rate, broadband THz generation in organic crystal BNA with diamond substrate.

We demonstrate a 13.3 MHz repetition rate, broadband THz source with milliwatt- average power, obtained by collinear optical rectification of a high-power Yb-doped thin-disk laser in the organic crystal BNA (N-benzyl-2-methyl-4-nitroaniline). Our source reaches a maximum THz average power of 0.95 mW with an optical-to-THz efficiency of 4×10-4 and a spectral bandwidth spanning up to 6 THz at -50 dB, driven by 2.4 W average power (after an optical chopper with duty cycle of 10%), 85 fs-pulses. This high average power excitation was possible without damaging the crystal by using a diamond-heatsinked crystal with significantly improved thermal properties. To the best of our knowledge, this result represents the highest THz average power reported so far using the commercially available organic crystal BNA, showing the potential of these crystals for high average power, high repetition rate femtosecond excitation. The combination of high power, high dynamic range, high repetition rate and broadband spectrum makes the demonstrated THz source highly attractive to improve various time-domain spectroscopy applications. Furthermore, we present a first exploration of the thermal behavior of BNA in this excitation regime, showing that thermal effects are the main limitation in average power scaling in these crystals.

Modification of Parks Classification of Cryptoglandular Anal Fistula.

BACKGROUND: The Parks classification has been used for the classification of anal fistula for several years, but it does not allow for risk factors for failure after surgery. OBJECTIVE: This study aimed to describe a modification of the Parks classification of anal fistula and examine its predictive validity in the assessment of the outcome of anal fistula in terms of failure of healing and fecal incontinence. DESIGN: This is a retrospective review of a prospective database. SETTING: This study was conducted in the Colorectal Surgery Unit, Mansoura University Hospitals. PATIENTS: Adult patients with anal fistula who underwent surgery were included. INTERVENTIONS: Five risk factors for failure after fistula surgery were identified from the literature and were examined by multivariate analysis of our patients. Four risk factors proved to be significant independent predictors of failure: secondary extensions, horseshoe fistula, previous fistula surgery, and anterior anal fistula in women. We modified the Parks classification by dividing the transsphincteric type into high and low and by grouping supra- and extrasphincteric anal fistulas into 1 group. The first 3 stages were subdivided according to the absence or presence of predictors of failure. MAIN OUTCOME MEASURES: The primary outcome measured was the validity of the modified Parks classification with regard to the rates of failure and fecal incontinence after surgical treatment of each stage of anal fistula. RESULTS: A total of 665 patients with cryptoglandular anal fistula were included. Failure rates increased from 2.3% (95% CI, 0.9%-4.7%), to 17.4% (95% CI, 10.8%-25.9%), 19.5% (95% CI, 15%-24.6%), and 30.7% (95% CI, 9.1%-61.4%) across the 4 stages. The area under the receiver operating characteristic curve was 0.90 (95% CI, 0.85-0.94) indicating the strong discriminative ability of the final multivariable predictive model. The increase in failure and incontinence rates across the fistula stages was significant. LIMITATIONS: This is a retrospective, single-center study. CONCLUSION: Inclusion of predictors of poor outcome into the modified classification helped differentiate simple and complex fistulas within each stage and between the different stages, which can help in assessment and decision making for anal fistula. See Video Abstract at http://links.lww.com/DCR/B441. MODIFICACIN DE LA CLASIFICACIN DE PARKS DE LA FSTULA ANAL CRIPTOGLANDULAR: ANTECEDENTES:La clasificación de Parks se ha utilizado para la clasificación de la fístula anal durante varios años, sin embargo, no tuvo en cuenta los factores de riesgo de fracaso después de la cirugía.OBJETIVO:Describir una modificación de la clasificación de Parks de fístula anal y examinar su validez predictiva en la evaluación de los resultados de la fístula anal en términos de fracaso de la cicatrización e incontinencia fecal.DISEÑO:Revisión retrospectiva de la base de datos prospectiva.AJUSTE:Unidad de Cirugía Colorrectal, Hospital Universitario de Mansoura.PACIENTES:Pacientes adultos con fístula anal intervenidos quirúgicamente.INTERVENCIONES:Se identificaron cinco factores de riesgo de fracaso después de la cirugía de fístula de la literatura y se examinaron mediante análisis multivariante de nuestros pacientes. Cuatro factores de riesgo demostraron ser importantes predictores independientes de fracaso: extensiones secundarias, fístula en herradura, cirugía de fístula previa y fístula anal anterior en mujeres. Modificamos la clasificación de Parks dividiendo el tipo transesfinteriano en alto y bajo y agrupando la fístula anal supraesfinteriana y extraesfinteriana en un grupo. Las tres primeras etapas se subdividieron según la ausencia o presencia de predictores de fracaso.PRINCIPALES MEDIDAS DE RESULTADO:Validez de la clasificación de Parks modificada con respecto a las tasas de fracaso e incontinencia fecal después del tratamiento quirúrgico de cada etapa de la fístula anal.RESULTADOS:Se incluyeron 665 pacientes con fístula anal criptoglandular. Las tasas de fracaso aumentaron del 2,3% (IC del 95%: 0,9-4,7%), al 17,4% (IC del 95%: 10,8 al 25,9%), 19,5% (IC del 95%: 15-24,6%) y 30,7% (95% IC: 9,1- 61,4%) en las cuatro etapas. El área bajo la curva característica operativa del receptor fue 0,90 (IC del 95%: 0,85-0,94), lo que indica una fuerte capacidad discriminativa del modelo predictivo multivariable final. El aumento en las tasas de fracaso e incontinencia en las etapas de la fístula fue significativo.LIMITACIONES:Estudio retrospectivo, unicéntrico.CONCLUSIÓN:La inclusión de predictores de mal resultado en la clasificación modificada ayudó a diferenciar las fístulas simples y complejas dentro de cada etapa y entre las diferentes etapas, lo que puede ayudar en la evaluación y toma de decisiones para la fístula anal. Consulte Video Resumen en http://links.lww.com/DCR/B441.