Real-time administration of indocyanine green in combination with computer vision and artificial intelligence for the identification and delineation of colorectal liver metastases.

Introduction: Fluorescence guided surgery for the identification of colorectal liver metastases (CRLM) can be better with low specificity and antecedent dosing impracticalities limiting indocyanine green (ICG) usefulness currently. We investigated the application of artificial intelligence methods (AIM) to demonstrate and characterise CLRMs based on dynamic signalling immediately following intraoperative ICG administration. Methods: Twenty-five patients with liver surface lesions (24 CRLM and 1 benign cyst) undergoing open/laparoscopic/robotic procedures were studied. ICG (0.05 mg/kg) was administered with near-infrared recording of fluorescence perfusion. User-selected region-of-interest (ROI) perfusion profiles were generated, milestones relating to ICG inflow/outflow extracted and used to train a machine learning (ML) classifier. 2D heatmaps were constructed in a subset using AIM to depict whole screen imaging based on dynamic tissue-ICG interaction. Fluorescence appearances were also assessed microscopically (using H&E and fresh-frozen preparations) to provide tissue-level explainability of such methods. Results: The ML algorithm correctly classified 97.2 % of CRLM ROIs (n = 132) and all benign lesion ROIs (n = 6) within 90-s of ICG administration following initial mathematical curve analysis identifying ICG inflow/outflow differentials between healthy liver and CRLMs. Time-fluorescence plots extracted for each pixel in 10 lesions enabled creation of 2D characterising heatmaps using flow parameters and through unsupervised ML. Microscopy confirmed statistically less CLRM fluorescence vs adjacent liver (mean ± std deviation signal/area 2.46 ± 9.56 vs 507.43 ± 160.82 respectively p < 0.001) with H&E diminishing ICG signal (n = 4). Conclusion: ML accurately identifies CRLMs from surrounding liver tissue enabling representative 2D mapping of such lesions from their fluorescence perfusion patterns using AIM. This may assist in reducing positive margin rates at metastatectomy and in identifying unexpected/occult malignancies.

Defining a textbook outcome for the resection of colorectal liver metastases.

INTRODUCTION: Textbook outcomes (TBO) are composite measures of care which may be superior in assessing quality compared to traditional methods. We aim to define TBO which are specific to surgical resection of colorectal liver metastases, and investigate their impact on survival. METHODS: Single center analysis of all liver resections performed at our center from 2009 to 2020. A Cox model was used to identify perioperative outcomes which impacted on overall survival. These were retained with important postoperative outcomes to form a "TBO." The impact of a TBO on overall survival was investigated using Kaplan-Meier curve analysis. RESULTS: TBO was achieved in 72.2% (197/273) of resections. Major morbidity (Clavien-Dindo ≥3) at 19.4% was the major limiting factor in not achieving a TBO. TBO was associated with improved 3-year (77% vs. 55%), 5-year (60.7% vs. 42.5%), and median (93 vs. 44 months) overall survival (log-rank test, p = 0.006). Multivariable analysis revealed age >65 years, American Society of Anaesthesiologists Grade III-IV, and resection of >2 segments as factors predictive of not achieving a TBO. CONCLUSION: TBO is a useful composite measure in surgery for colorectal liver metastases. It can highlight areas which may be targeted for quality improvement and be useful as a tool to examine variation between centers. Achieving a TBO is associated with a significant improvement in survival.

Perforated jejunal diverticula: a case report.

INTRODUCTION: Jejunal diverticula are rare and are usually asymptomatic. However, they may cause chronic non-specific symptoms or rarely lead to an acute presentation. CASE PRESENTATION: We report the case of an 82-year-old Caucasian woman presenting with a one-day history of generalized abdominal pain, with three episodes of vomiting. An abdominal X-ray displayed multiple dilated loops of the small bowel. A subsequent computed tomography scan of the abdomen and pelvis revealed a thickening of the duodenum and dilatation of the proximal jejunum. Multiple small bowel diverticula were identified with surrounding pockets of free air adjacent to the jejunal diverticula suggestive of a small bowel perforation. Our patient underwent a laparotomy, which identified multiple jejunal diverticula with two pinhole jejunal perforations and associated fecal contamination. The perforations were repaired with primary closure and extensive washout was performed. CONCLUSION: Jejunal diverticulosis in the elderly can lead to significant morbidity and mortality and so should be suspected in those presenting with crampy abdominal pain and altered bowel habits.