Clinical application of machine learning and computer vision to indocyanine green quantification for dynamic intraoperative tissue characterisation: how to do it.

INTRODUCTION: Indocyanine green (ICG) quantification and assessment by machine learning (ML) could discriminate tissue types through perfusion characterisation, including delineation of malignancy. Here, we detail the important challenges overcome before effective clinical validation of such capability in a prospective patient series of quantitative fluorescence angiograms regarding primary and secondary colorectal neoplasia. METHODS: ICG perfusion videos from 50 patients (37 with benign (13) and malignant (24) rectal tumours and 13 with colorectal liver metastases) of between 2- and 15-min duration following intravenously administered ICG were formally studied (clinicaltrials.gov: NCT04220242). Video quality with respect to interpretative ML reliability was studied observing practical, technical and technological aspects of fluorescence signal acquisition. Investigated parameters included ICG dosing and administration, distance-intensity fluorescent signal variation, tissue and camera movement (including real-time camera tracking) as well as sampling issues with user-selected digital tissue biopsy. Attenuating strategies for the identified problems were developed, applied and evaluated. ML methods to classify extracted data, including datasets with interrupted time-series lengths with inference simulated data were also evaluated. RESULTS: Definable, remediable challenges arose across both rectal and liver cohorts. Varying ICG dose by tissue type was identified as an important feature of real-time fluorescence quantification. Multi-region sampling within a lesion mitigated representation issues whilst distance-intensity relationships, as well as movement-instability issues, were demonstrated and ameliorated with post-processing techniques including normalisation and smoothing of extracted time-fluorescence curves. ML methods (automated feature extraction and classification) enabled ML algorithms glean excellent pathological categorisation results (AUC-ROC > 0.9, 37 rectal lesions) with imputation proving a robust method of compensation for interrupted time-series data with duration discrepancies. CONCLUSION: Purposeful clinical and data-processing protocols enable powerful pathological characterisation with existing clinical systems. Video analysis as shown can inform iterative and definitive clinical validation studies on how to close the translation gap between research applications and real-world, real-time clinical utility.

Preoperative C-reactive protein and other inflammatory markers as predictors of postoperative complications in patients with colorectal neoplasia.

BACKGROUND: Inflammatory markers are measured following colorectal surgery to detect postoperative complications. However, the association of these markers preoperatively with subsequent postoperative course has not yet been usefully studied. AIM: The aim of this study is to assess the ability of preoperative C-reactive protein (CRP) and other inflammatory marker measurements in the prediction of postoperative morbidity after elective colorectal surgery. METHODS: This is a retrospective study which catalogs 218 patients undergoing elective, potentially curative surgery for colorectal neoplasia. Preoperative laboratory results of the full blood count (FBC), C-reactive protein (CRP) and carcinoembryonic antigen (CEA) were recorded. Multivariable analysis was performed to examine preoperative variables against 30-day postoperative complications by type and grade (Clavien-Dindo (CD)), adjusting for age, sex, BMI, smoking status, medical history, open versus laparoscopic operation, and tumor characteristics. RESULTS: Elevated preoperative CRP (≥ 5 mg/L) was significantly predictive of all-cause mortality, with an OR of 17.0 (p < 0.001) and was the strongest factor to predict a CD morbidity grade ≥ 3 (OR 41.9, p < 0.001). Other factors predictive of CD morbidity grade ≥ 3 included smoking, elevated preoperative platelet count and elevated preoperative neutrophil-lymphocyte ratio (OR 15.6, 8.6, and 6.3 respectively, all p < 0.05). CRP values above 5.5 mg/L were indicative of all-cause morbidity (AUC = 0.871), and values above 17.5 mg/L predicted severe complications (AUC = 0.934). CONCLUSIONS: Elevated preoperative CRP predicts increased postoperative morbidity in this patient cohort. The results herein aid risk and resource stratification and encourage preoperative assessment of inflammatory propensity besides simple sepsis exclusion.

Acute colonic pseudo-obstruction post-cesarean section is not a benign entity: A case series and review of the literature.

Acute colonic pseudo-obstruction (ACPO) is an infrequent occurrence after cesarean section. Anecdotal evidence suggests that the clinical course of ACPO in the obstetric setting is different to that seen in non-pregnant adult patients with ACPO secondary to alternative causes, such as systemic illnesses, the use of certain medications, and after non-abdominal surgery. The risk of progression to ischemia and perforation, as well as the need for emergency surgery, appears to be higher after cesarean section. Here we describe the clinical course of ACPO in four patients after cesarean section from our institution, followed by a review of the literature and a discussion of the important issues surrounding this condition in the postpartum time period. The findings from our cohort of patients and the reports from the medical literature support a hands-on combined approach from a group of specialists including obstetricians, surgeons, radiologists, and enterostomal therapists. Immediate imaging followed by regular observation is mandatory for any patient being managed conservatively. Early use of endoscopic decompression should be considered for patients who are not resolving with a conservative approach. Clinical signs of peritonism or radiological signs of ischemia or perforation in patients with ACPO mandate immediate surgical intervention. Appropriate postoperative care is necessary to deal with the complex physiological and psychological consequences of emergency surgery and potential stoma formation so soon after cesarean section.

Guideline for the diagnosis and treatment of Faecal Incontinence-A UEG/ESCP/ESNM/ESPCG collaboration.

INTRODUCTION: The goal of this project was to create an up-to-date joint European clinical practice guideline for the diagnosis and treatment of faecal incontinence (FI), using the best available evidence. These guidelines are intended to help guide all medical professionals treating adult patients with FI (e.g., general practitioners, surgeons, gastroenterologists, other healthcare workers) and any patients who are interested in information regarding the diagnosis and management of FI. METHODS: These guidelines have been created in cooperation with members from the United European Gastroenterology (UEG), European Society of Coloproctology (ESCP), European Society of Neurogastroenterology and Motility (ESNM) and the European Society for Primary Care Gastroenterology (ESPCG). These members made up the guideline development group (GDG). Additionally, a patient advisory board (PAB) was created to reflect and comment on the draft guidelines from a patient perspective. Relevant review questions were established by the GDG along with a set of outcomes most important for decision making. A systematic literature search was performed using these review questions and outcomes as a framework. For each predefined review question, the study or studies with the highest level of study design were included. If evidence of a higher-level study design was available, no lower level of evidence was sought or included. Data from the studies were extracted by two reviewers for each predefined important outcome within each review question. Where possible, forest plots were created. After summarising the results for each review question, a systematic quality assessment using the GRADE (Grading of Recommendations, Assessment, Development and Evaluations) approach was performed. For each review question, we assessed the quality of evidence for every predetermined important outcome. After evidence review and quality assessment were completed, recommendations could be formulated. The wording used for each recommendation was dependent on the level of quality of evidence. Lower levels of evidence resulted in weaker recommendations and higher levels of evidence resulted in stronger recommendations. Recommendations were discussed within the GDG to reach consensus. RESULTS: These guidelines contain 45 recommendations on the classification, diagnosis and management of FI in adult patients. CONCLUSION: These multidisciplinary European guidelines provide an up-to-date comprehensive evidence-based framework with recommendations on the diagnosis and management of adult patients who suffer from FI.

Topic update: effects of colorectal cancer treatments on female fertility and potential methods for fertility preservation.

PURPOSE: Preservation of fertility in young females with a diagnosis of colorectal cancer is gaining increasing importance as survival rates of cancer increase. This review examines the effects of pelvic surgery, chemotherapy, and radiotherapy on fecundity. It also discusses the options available to patients including ovarian transposition, gonadotropin-releasing hormone analogs, embryo and ovarian cryopreservation, and ovarian tissue transplantation. METHODS: A search of MEDLINE, EMBASE, and the Cochrane library was performed using keywords and exploded Mesh search headings and the subsequent articles were reviewed. Relevant studies were included. RESULTS: There are no studies that examine the effect of surgery for colorectal cancer on female fertility, in particular, surgery below the peritoneal reflection for rectal cancer. However, patients with familial adenomatous polyposis have a similar fecundity before and after proctocolectomy with ileal pouch-anal anastomosis. These patients did significantly better than patients with ulcerative colitis who underwent the same procedure. There is conflicting evidence regarding the effects of open vs laparoscopic surgery on fertility. Oxaliplatin, an adjuvant therapy, has moderate gonadotoxic effects. Fluorouracil is considered to have almost no effect on human reproductive function. Gonadotropin-releasing hormone agonists are currently used to preserve female fecundity during chemotherapy. A recent update of patients treated for Hodgkin lymphoma showed that significantly fewer women treated with a gonadotropin-releasing hormone agonist during chemotherapy exhibited premature ovarian failure. Ovarian transposition reduces the radiation dose to approximately 5% to 10% of the dose to the ovaries in their normal position. Other options are available to women with cancer who wish to preserve their germ line, including embryo and oocyte cryopreservation and ovarian tissue cryopreservation. CONCLUSION: Significant advances are now allowing females to preserve their fertility after cancer treatment. It is essential that patients receive adequate fertility counseling before any intervention to give them an opportunity to consider fertility alternatives.

The effects of low-frequency endo-anal electrical stimulation on faecal incontinence: a prospective study.

BACKGROUND AND AIMS: Faecal incontinence is a distressing problem that is often not amenable to surgical correction. Chronic low-frequency electrical stimulation of damaged axons is thought to reduce synaptic resistance, increase the size of motor units by axonal sprouting and increase the rate of conduction of the pudendal nerve. The aim of this study was to prospectively evaluate the effect of chronic low-frequency endo-anal electrical stimulation on faecal incontinence using a home-based unit and hospital-supervised therapy. MATERIALS AND METHODS: Forty-eight patients with faecal incontinence completed a prospective randomised trial. Patients were allocated randomly to one of two groups; group 1 was exposed to endo-anal pudendal nerve stimulation daily at home with a portable home unit, group 2 attended the physiotherapy department for endo-anal electrical stimulation under supervision. RESULTS: Continence scores improved significantly after treatment in both groups (p<0.001). Both groups showed improved manometric scores, although only group 1 showed significant improvement in both resting and squeeze pressures (mean total resting pressure 184-224 mmHg, p<0.001; mean total squeeze pressure 253-337 mmHg, p<0.001). This was also reflected by an improvement in quality of life in both groups. CONCLUSIONS: Low-frequency endo-anal electrical stimulation significantly improves continence scores and quality of life in patients with faecal incontinence not amenable to surgical correction. It leads to improved manometric values when carried out on a daily basis with a portable home unit.

Increased adhesion molecule expression in serosal fibroblasts isolated from patients with inflammatory bowel disease is secondary to inflammation.

OBJECTIVE: To examine the expression of adhesion molecules by serosal and dermal fibroblasts in patients with inflammatory bowel disease. SUMMARY BACKGROUND DATA: The pathophysiologic process that leads to stricture formation in Crohn's disease (CD) is unknown. Serosal fibroblasts in these patients have an enhanced ability to contract collagen. This property may be reflected in fibroblast adhesion molecule expression, which in turn may be constitutive or secondary to the inflammatory process in patients with CD. METHODS: Fibroblasts were isolated from inflamed and macroscopically normal serosa of patients with CD or ulcerative colitis (UC) and from normal serosa of patients with colon cancer. Dermal fibroblasts were also isolated from the wound edge. Cell surface and whole cell expression of ICAM-1 were evaluated by flow cytometry and Western blot analysis, respectively. NFkappaB was measured by mobility shift assay in parallel experiments. Interleukin 1beta was added to the culture medium. RESULTS: Expression of ICAM-1 and NFkappaB, increased in patients with both CD and UC, was unaltered by interleukin 1beta. The whole cell concentration of ICAM-1 was greater in patients with CD than in patients with UC. Dermal fibroblasts did not display these features. CONCLUSIONS: Patients with inflammatory bowel disease display enhanced ICAM-1 expression in serosal fibroblasts but not dermal fibroblasts, indicating a secondary response to inflammation.