Biliary Leaks: Multidisciplinary Approach to Diagnosis and Treatment.

Bile leaks arise from various causes such as trauma, complications after hepatobiliary surgery, and intrahepatic malignancies or their associated liver-directed treatments. Bile leaks can result in significant morbidity and mortality. Delayed diagnosis is not uncommon due to nonspecific manifestations; therefore, a high clinical suspicion is needed. A multidisciplinary approach for treatment of biliary leaks with prompt referral to tertiary care centers with experienced hepatobiliary surgeons, advanced endoscopists, and interventional radiologists is needed to address these challenging complications. Management of biliary leaks can range from conservative management to open surgical repair. Minimally invasive procedures play a crucial role in biliary leak treatment, and the interventional radiologist can help guide appropriate management on the basis of a clear understanding of the pathophysiology of biliary leaks and a current knowledge of the armamentarium of treatment options. In most cases, a simple diversion of bile to decompress the biliary system may prove effective. However, persistent and high-output biliary leaks require delineation of the source with tailored treatment options to control the leak. This may be done by additional diversions, occluding the source, reestablishing connections, or using a combination of therapies to bridge to more definitive surgical interventions. The authors describe the different treatment options and emphasize the role of interventional radiology. ©RSNA, 2024.

Real-time detection of gastrointestinal leaks via bismuth chelate-enhanced X-ray gastroenterography.

Anastomotic leaks are among the most dreaded complications following gastrointestinal (GI) surgery, and contrast-enhanced X-ray gastroenterography is considered the preferred initial diagnostic method for GI leaks. However, from fundamental research to clinical practice, the only oral iodinated contrast agents currently available for GI leaks detection are facing several challenges, including low sensitivity, iodine allergy, and contraindications in patients with thyroid diseases. Herein, we propose a cinematic contrast-enhanced X-ray gastroenterography for the real-time detection of GI leaks with an iodine-free bismuth chelate (Bi-DTPA) for the first time. The Bi-DTPA, synthesized through a straightforward one-pot method, offers distinct advantages such as no need for purification, a nearly 100 % yield, large-scale production capability, and good biocompatibility. The remarkable X-ray attenuation properties of Bi-DTPA enable real-time dynamic visualization of whole GI tract under both X-ray gastroenterography and computed tomography (CT) imaging. More importantly, the leaky site and severity can be both clearly displayed during Bi-DTPA-enhanced gastroenterography in a rat model with esophageal leakage. The proposed movie-like Bi-DTPA-enhanced X-ray imaging approach presents a promising alternative to traditional GI radiography based on iodinated molecules. It demonstrates significant potential in addressing concerns related to iodine-associated adverse effects and offers an alternative method for visually detecting gastrointestinal leaks.

Role of indocyanine green fluorescence imaging for evaluating blood supply in the gastric conduit via the substernal route after McKeown minimally invasive esophagectomy.

BACKGROUND: Anastomotic leakage (AL) is a determining factor of morbidity and mortality after esophagectomy. Adequate perfusion of the gastric conduit is crucial for AL prevention. This study aimed to determine whether intraoperative angiography using indocyanine green (ICG) fluorescence improves the incidence of AL after McKeown minimally invasive esophagectomy (MIE) with gastric conduit via the substernal route (SR). METHODS: This retrospective cohort study included 120 patients who underwent MIE with gastric conduit via SR for esophageal cancer between February 2019 and April 2023. Of 120 patients, 88 experienced intraoperative angiography using ICG (ICG group), and 32 patients experienced intraoperative angiography without ICG (no-ICG group). Baseline characteristics and operative outcomes, including AL as the main concern, were compared between the 2 groups. In addition, the outcomes among patients in the ICG group with different levels of fluorescence intensity were compared. RESULTS: The ICG and no-ICG groups were comparable in baseline characteristics and operative outcomes. There was no significant difference between the 2 groups regarding the rate of AL (31.0% vs 37.5%; P = .505), median dates of AL (9 vs 9 days; P = .810), and severity of AL (88.9%, 11.11%, and 0.0% vs 66.7%, 16.7%, and 16.7% for grades I, II, and III, respectively; P = .074). Patients in the ICG group with lower intensity of ICG had higher rates of leakage (24.6%, 39.3%, and 100% in levels I, II, and III of ICG intensity, respectively; P = .04). CONCLUSION: The use of ICG did not seem to reduce the rate of AL. However, abnormal intensity of ICG fluorescence was associated with a higher rate of AL, which implies a predictive potential.

Routine Upper Gastrointestinal Series Post-bariatric Surgery: Predictors, Usage, and Utility.

OBJECTIVE: To investigate usage and utility of routine upper gastrointestinal (UGI) series in the immediate post-operative period to evaluate for leak and other complications. METHODS: Single institution IRB-approved retrospective review of patients who underwent bariatric procedure between 01/08 and 12/12 with at least 6-month follow-up. RESULTS: Out of 135 patients (23%) who underwent routine UGI imaging, 32% of patients were post-gastric bypass (127) versus 4% of sleeve gastrectomy (8). In patients post-gastric bypass, 22 were found with delayed contrast passage, 3 possible obstruction, 4 possible leak, and only 1 definite leak. In patients post-sleeve gastrectomy, 2 had delayed passage of contrast without evidence of a leak. No leak was identified in 443 patients (77%) who did not undergo imaging. The sensitivity and specificity of UGI series for the detection of leak in gastric bypass patients were 100% and 97%, respectively, and the positive and negative predictive values were 20% and 100%, respectively. On univariate and multivariate analysis, sleeve gastrectomy patients (OR 0.4 sleeve vs bypass; P < 0.01) and male patients (OR 0.4 M vs F; P 0.02) were less likely to undergo routine UGI series (OR 0.4 M vs F; P 0.02). CONCLUSION: Routine UGI series may be of limited value for the detection of anastomotic leaks after gastric bypass or sleeve gastrectomy and patients should undergo routine imaging based on clinical parameters. Gastric bypass procedure and female gender were factors increasing the likelihood of routine post-operative UGI. Further larger scale analysis of this important topic is warranted.

Quantification of fluorescence angiography for visceral perfusion assessment: measuring agreement between two software algorithms.

BACKGROUND: Indocyanine green fluorescence angiography (ICG-FA) may reduce perfusion-related complications of gastrointestinal anastomosis. Software implementations for quantifying ICG-FA are emerging to overcome a subjective interpretation of the technology. Comparison between quantification algorithms is needed to judge its external validity. This study aimed to measure the agreement for visceral perfusion assessment between two independently developed quantification software implementations. METHODS: This retrospective cohort analysis included standardized ICG-FA video recordings of patients who underwent esophagectomy with gastric conduit reconstruction between August 2020 until February 2022. Recordings were analyzed by two quantification software implementations: AMS and CPH. The quantitative parameter used to measure visceral perfusion was the normalized maximum slope derived from fluorescence time curves. The agreement between AMS and CPH was evaluated in a Bland-Altman analysis. The relation between the intraoperative measurement of perfusion and the incidence of anastomotic leakage was determined for both software implementations. RESULTS: Seventy pre-anastomosis ICG-FA recordings were included in the study. The Bland-Altman analysis indicated a mean relative difference of + 58.2% in the measurement of the normalized maximum slope when comparing the AMS software to CPH. The agreement between AMS and CPH deteriorated as the magnitude of the measured values increased, revealing a proportional (linear) bias (R2 = 0.512, p < 0.001). Neither the AMS nor the CPH measurements of the normalized maximum slope held a significant relationship with the occurrence of anastomotic leakage (median of 0.081 versus 0.074, p = 0.32 and 0.041 vs 0.042, p = 0.51, respectively). CONCLUSION: This is the first study to demonstrate technical differences in software implementations that can lead to discrepancies in ICG-FA quantification in human clinical cases. The possible variation among software-based quantification methods should be considered when interpreting studies that report quantitative ICG-FA parameters and derived thresholds, as there may be a limited external validity.

Blood flow evaluation of reconstructed gastric tube in esophageal surgery using near-infrared imaging and retrospective time-intensity curve analysis.

PURPOSE: Near-infrared fluorescence imaging using indocyanine green (ICG-NIFI) can visualize a blood flow in reconstructed gastric tube; however, it depends on surgeon's visual assessment. The aim of this study was to re-analyze the ICG-NIFI data by an evaluator independent from the surgeon and feasibility of creating the time-intensity curve (TIC). METHODS: We retrospectively reviewed 97 patients who underwent esophageal surgery with gastric tube reconstruction between January 2017 and November 2022. From the stored ICG videos, fluorescence intensity was examined in the four regions of interest (ROIs), which was set around the planned anastomosis site on the elevated gastric tube. After creation the TICs using the OpenCV library, we measured the intensity starting point and time constant and assessed the correlation between the anastomotic leakage. RESULTS: Postoperative leakage occurred for 12 patients. The leakage group had significantly lack of blood flow continuity between the right and left gastroepiploic arteries (75.0% vs. 22.4%; P < 0.001) and tended to have slower ICG visualization time assessed by the surgeon's eyes (40 vs. 32 s; P = 0.066). TIC could create in 65 cases. Intensity starting point at all ROIs was faster than the surgeon's assessment. The leakage group tended to have slower intensity starting point at ROI 3 compared to those in the non-leakage group (22.5 vs. 19.0 s; P = 0.087). CONCLUSION: A TIC analysis of ICG-NIFI by an independent evaluator was able to quantify the fluorescence intensity changes that the surgeon had visually determined.

Bioresorbable shape-adaptive structures for ultrasonic monitoring of deep-tissue homeostasis.

Monitoring homeostasis is an essential aspect of obtaining pathophysiological insights for treating patients. Accurate, timely assessments of homeostatic dysregulation in deep tissues typically require expensive imaging techniques or invasive biopsies. We introduce a bioresorbable shape-adaptive materials structure that enables real-time monitoring of deep-tissue homeostasis using conventional ultrasound instruments. Collections of small bioresorbable metal disks distributed within thin, pH-responsive hydrogels, deployed by surgical implantation or syringe injection, allow ultrasound-based measurements of spatiotemporal changes in pH for early assessments of anastomotic leaks after gastrointestinal surgeries, and their bioresorption after a recovery period eliminates the need for surgical extraction. Demonstrations in small and large animal models illustrate capabilities in monitoring leakage from the small intestine, the stomach, and the pancreas.

Calcifications in the descending thoracic aorta predict postoperative anastomotic leakages after esophagectomy for cancer.

BACKGROUND: Anastomotic leak is one of the most feared complications of esophagectomy. Previous studies have suggested a potential link between aortic calcifications detected on routine preoperative CT scans and increased risk of anastomotic leak after esophagectomy. This study aims to investigate whether clinicians' assessment of aortic calcifications can predict the occurrence of anastomotic leaks in patients undergoing esophagectomy for cancer. METHODS: A long-term follow-up was conducted on consecutive patients with esophageal cancer who underwent elective open esophagectomy at a Finnish tertiary hospital. Aortic calcifications were evaluated based on CT scans and categorized on a 0-3 scale reflecting the number of calcifications in the affected segment of the aorta. Reviewers assessing the calcifications were blinded to clinical details and postoperative outcomes. RESULTS: The study included 97 patients (median age: 64 years and range: 43-78; 20% female), with a median follow-up time of 1307 (2-1540) days. Among them, 22 patients (23%) had postoperative anastomotic leak. We observed a significant association between calcifications in the descending aorta and a higher risk of anastomotic leak (p = 0.007), as well as an earlier occurrence of leak postoperatively (p = 0.013). However, there was no association between aortic calcifications and increased mortality. CONCLUSIONS: Presence of calcifications in the descending aorta is independently associated with an increased risk of anastomotic leaks following esophagectomy for cancer. Identifying patients at higher risk for this complication could facilitate appropriate pre- and postoperative interventions, as well as enable earlier diagnosis and treatment to mitigate the severity of the complication.

Radiographic Evaluation of Ileal Pouch Disorders: A Systematic Review.

BACKGROUND: Radiographic imaging of the abdomen and pelvis plays an important role in the diagnosis and management of ileal pouch disorders with modalities including CT, MRI, contrasted pouchography, and defecography. OBJECTIVES: To perform a systematic review of the literature and describe applications of cross-sectional imaging, pouchography, defecography, and ultrasonography. DATA SOURCES: PubMed, Google Scholar, and Cochrane database. STUDY SELECTION: Relevant articles on endoscopy in ileal pouches published between January 2003 and June 2023 in English were included on the basis of Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. INTERVENTION: Main abdominal and pelvic imaging modalities and their applications in the diagnosis of ileal pouch disorders were included. MAIN OUTCOME MEASURES: Accuracy in characterization of ileal pouch disorders. RESULTS: CT is the test of choice for the evaluation of acute anastomotic leaks, perforation, and abscess(es). MRI of the pelvis is suitable for the assessment of chronic anastomotic leaks and their associated fistulas and sinus tracts, as well as for the penetrating phenotype of Crohn's disease of the pouch. CT enterography and magnetic resonance enterography are useful in assessing intraluminal, intramural, and extraluminal disease processes of the pouch and prepouch ileum. Water-soluble contrast pouchography is particularly useful for evaluating acute or chronic anastomotic leaks and outlines the shape and configuration of the pouch. Defecography is the key modality to evaluate structural and functional pouch inlet and outlet obstructions. Ultrasonography can be performed to assess the pouch in experienced IBD centers. LIMITATIONS: This is a qualitative, not quantitative, review of mainly case series and case reports. CONCLUSIONS: Abdominopelvic imaging, along with clinical and endoscopic evaluation, is imperative for accurately assessing structural, inflammatory, functional, and neoplastic disorders. See video from symposium .

Is proctoscopy sufficient for the evaluation of colorectal anastomosis prior to ileostomy reversal? A nationwide retrospective analysis of the Italian Society of Surgical Oncology Colorectal Cancer Network Collaborative group (SICO-CCN).

AIM: Several methods for assessing anastomotic integrity have been proposed, but the best is yet to be defined. The aim of this study was to compare the different methods to assess the integrity of colorectal anastomosis prior to ileostomy reversal. METHOD: A retrospective cohort analysis on patients between 1 January 2010 and 31 December 2020 with a defunctioning stoma for middle and low rectal anterior resection was performed. A propensity score matching comparison between patients who underwent proctoscopy alone and patients who underwent proctoscopy plus any other preoperative method to assess the integrity of colorectal anastomosis prior to ileostomy reversal (transanal water-soluble contrast enema via conventional radiology, transanal water-soluble contrast enema via CT, and magnetic resonance) was performed. RESULTS: The analysis involved 1045 patients from 26 Italian referral colorectal centres. The comparison between proctoscopy alone versus proctoscopy plus any other preoperative tool showed no significant differences in terms of stenoses (p = 0.217) or leakages (p = 0.103) prior to ileostomy reversal, as well as no differences in terms of misdiagnosed stenoses (p = 0.302) or leakages (p = 0.509). Interestingly, in the group that underwent proctoscopy and transanal water-soluble contrast enema the comparison between the two procedures demonstrated no significant differences in detecting stenoses (2 vs. 0, p = 0.98), while there was a significant difference in detecting leakages in favour of transanal water-soluble contrast enema via CT (3 vs. 12, p = 0.03). CONCLUSIONS: We can confirm that proctoscopy alone should be considered sufficient prior to ileostomy reversal. However, in cases in which the results of proctoscopy are not completely clear or the surgeon remains suspicious of an anastomotic leakage, transanal water-soluble contrast enema via CT could guarantee its detection.

Added value of positive intraluminal contrast CT over fluoroscopic examination for detecting gastrointestinal leakage after gastrointestinal surgery.

We aimed to evaluate the added value of positive intraluminal contrast computed tomography (CT) over fluoroscopy in detecting anastomotic leakage after gastrointestinal (GI) surgery. A total of 141 GI surgery patients who underwent fluoroscopic examination and CT were included. Two radiologists reviewed the fluoroscopic images with and without CT to determine anastomotic leakage on a 5-point confidence scale and graded the leakage on a 4-point grading system. The hospital stay duration and treatment type were recorded. The radiologists' diagnostic performance in determining leakage was compared using the receiver operating characteristics analysis, and interobserver agreement was analyzed. Fifty-three patients developed GI leakage. When CT was added to the fluoroscopic images, the area under the curve (AUC) values significantly increased for both reviewers. The interobserver agreement for leakage between the two reviewers was excellent and improved with the addition of CT (weighted kappa value, 0.869 versus 0.805). Postoperative intervention was more frequently performed (P < 0.001), and patients with leakage had a significantly longer mean postoperative hospital stay (45 days vs. 27 days) (P = 0.003). Thus, positive intraluminal contrast CT provides added value over fluoroscopic examination for detecting GI leakage in patients undergoing GI tract surgery, increasing AUC values, and improving interobserver agreement.

Impact of CT-measured sarcopenic obesity on postoperative outcomes following colon cancer surgery.

OBJECTIVE: This study aimed to investigate the influence of sarcopenic obesity on anastomotic leak following elective colon resection for non-metastatic colon cancer. Secondary outcomes included overall morbidity, mortality and length of hospital stay. METHODS: This retrospective observational study, conducted at a colorectal surgery referral centre, spanned from January 1, 2015, to January 1, 2020. A total of 544 consecutive patients who underwent elective colon resection were included in the analysis, excluding patients with rectal cancer, urgent surgery, absence of anastomosis, lack of imaging, multivisceral resections and synchronic tumours. RESULTS: Postoperative complications were observed in 177 (32.3%) patients, with 51 (9.31%) classified as severe (Clavien-Dindo > II). Sarcopenic obesity was identified in 9.39% of the sample and emerged as an independent predictor of increased overall morbidity [OR 2.15 (1.14-3.69); p = 0.016] and 30-day mortality [OR 5.07 (1.22-20.93); p = 0.03] and was significantly associated with the development of anastomotic leak [OR 2.95 (1.41-6.18); p = 0.007]. Furthermore, it increased the risk of reoperation and was linked to a prolonged length of hospital stay. CONCLUSIONS: CT-measured sarcopenic obesity demonstrates a discernible correlation with an elevated risk of postoperative morbidity and mortality in the context of colon cancer surgery.

Applications of indocyanine greenenhanced fluorescence in the laparoscopic treatment of colonic stricture after necrotizing enterocolitis.

BACKGROUND: The status of anastomotic blood perfusion is associated with the occurrence of anastomotic leakage after intestinal anastomosis. Fluorescence angiography (FA) with indocyanine green (ICG) can objectively assess intestinal blood perfusion. This study aims to investigate whether anastomotic perfusion assessment with ICG influences surgical decision-making during laparoscopic intestinal resection and primary anastomosis for colonic stricture after necrotizing enterocolitis. METHODS: Patients who underwent laparoscopic intestinal resection and primary anastomosis between January 2022 and December 2022 were retrospectively analyzed. Before intestinal anastomosis, the ICG fluorescence technology was used to evaluate the blood perfusion of intestinal tubes on both sides of the anastomosis. After the completion of primary anastomosis, the anastomotic blood perfusion was assessed again. RESULTS: Of the 13 cases, laparoscopy was used to determine the extent of the diseased bowel to be excised, and the normal bowel was preserved for anastomosis. The anastomosis was established under the guidance of ICG fluorescence technology, and FA was performed after anastomosis to confirm good blood flow in the proximal bowel. The anastomotic intestinal tube was changed in one case because FA showed a difference between the normal range of intestinal blood flow and the macroscopic prediction. There was no evidence of ICG allergy, anastomotic leakage, anastomotic stricture, or other complications. The median follow-up was 6 months, and all patients recovered well. CONCLUSIONS: The ICG fluorescence technology is helpful in precisely and efficiently determining the anastomotic intestinal blood flow during stricture resection and in avoiding anastomotic leakage caused by poor anastomotic intestinal blood flow to some extent, with satisfactory short-term efficacy.

Rat models of high risk colorectal anastomoses

Abstract Purpose: To evaluate the most frequent surgical techniques of high-risk colorectal anastomoses in rats. Methods: Wistar rats were enrolled in three different models comprising inflammatory (TNBS enema), vascular (portal vein occlusion) or obstructive (a non-ischemic constricting ring) mechanisms associated with colonic anastomosis that had accomplished after these former lesions. Histological analyses (Hematoxylin and eosin and Picrosirius red) were performed. Results: All anastomoses techniques were associated with risk factors and had complications, mainly anastomotic leakage. In Study 1, the use of a pharmacological agent, trinitrobenzene sulfonic acid (TNBS) mimicked an inflammatory bowel disease such as Crohn's disease with 50% of anastomosis leakage, the higher percentage among all models tested. In Study 2, after portal ischemia followed by reperfusion it was observed a dense neutrophil infiltrate in the midst of necrotic tissue and fibrin at the anastomotic site and 5 days after the anastomosis, no collagen was produced. In Study 3, 5 days after the mechanical obstruction some denuded areas of epithelium with marked oedema of mucosa and submucosa were seen, at the anastomotic site and anastomosis group showed some reduction of collagen density when compared with Control/Sham group. Conclusion: All the experimental surgical techniques tested in rats were associated with high-risk colorectal anastomoses and were useful to study colonic anastomotic healing and intestinal leakage.

Utilidad del estudio contrastado precoz del tracto digestivo superior después de cirugía bariátrica: ¿se justifica su uso rutinario? / Usefulness of upper gastrointestinal series to detect leaks in the early postoperative period of bariatric surgery

Background: Postoperative leaks are the most undesirable complication of bariatric surgery and upper gastrointestinal (GI) series are routinely ordered to rule them out. Despite the published literature recommending against its routine use, it is still being customarily used in Chile. Aim: To examine the usefulness of routine upper GI series using water-soluble iodinated contrast media for the detection of early postoperative leaks in patients undergoing bariatric surgery. Material and Methods: A cohort of 328 patients subjected to bariatric surgery was followed from October 2012 to October 2013. Most of them underwent sleeve gastrectomy. Results: Upper GI series on the first postoperative day were ordered to 308 (94%) patients. Postoperative leaks were observed in two patients, with an incidence of 0.6%. The sensitivity for upper GI series detection of leak was 0% and the negative predictive value was 99%. Conclusions: Routine upper GI series after bariatric surgery is not useful for the diagnosis of postoperative leak, given the low incidence of this complication and the low sensitivity of the technique.