Leaks were higher in participants commencing PD at 1 week after catheter insertion compared with the other 2 groups, and technique failure was higher in diabetics starting PD at 4 weeks.

Background: Dual-energy CT is able to distinguish between materials based on differences in X-ray absorption at different X-ray beam energies. The strong k-edge photoelectric effect of materials with a high atomic number makes this modality ideal for identifying iodine-containing compounds. We aim to evaluate dual-energy CT for the detection of Gastrografin (GG) (diatrizoate, Bayer PLC, Reading, UK) enteric contrast medium and validate the conditions for the measurement in ex vivo samples. Methods: Dual-energy CT acquisitions were performed to detect Gastrografin in serial dilutions of water, saline and body fluids. We also evaluated the stability of Gastrografin solutions over time at room temperature. Stool specimens were examined to validate the proposed study protocol for clinical applications. Results: Concentrations as low as 0.2% of Gastrografin were reproducibly detected in vitro and ex vivo samples by DECT, with linear readings ranging from 0.2% to 25% Gastrografin. Gastrografin was shown to be stable in ex vivo biological samples, and there was no difference in detection over time. Gastrografin was detected in stool specimens when administered orally. The detection curves followed the expected saturation effect at high concentrations of iodine. Conclusions: Dual-energy CT offers a convenient, quick, reliable and reproducible method for detecting and quantifying the presence of Gastrografin in ex vivo clinical specimens. Biological solutions containing Gastrografin are stable over time. A minimum dilution level of 25% is suggested to avoid beam saturation and inaccurate results.

Anastomotic leakage is the anathema of colorectal surgery. Its occurrence leads to increased morbidity and mortality and a prolonged hospital stay. Much work has gone into studying various biomarkers in drain fluid to facilitate early detection of anastomotic leak (AL). This 2a development study aims to assess the safety and feasibility of reliably detecting the iodine in Gastrografin (GG) in drain fluid and stool samples by Dual-Energy Computed Tomography (DECT). Methods This is a prospective, observational, controlled, consecutive cohort study establishing the safety and feasibility of the detection of GG in surgical drain fluid and stool as a biomarker of anastomotic leak when patients with a low pelvic colorectal anastomosis undergo luminal flushing of the rectal tube with GG. Results Ten consecutive patients were allocated to the saline flush group and the following ten to the GG flush group. Three patients in the saline flush group developed an AL. One patient in the GG flush group developed an AL. An elevation in the drain fluid GG was detected using DECT on the day of clinical deterioration. None of the patients in the control group were found to have a positive result on DECT. Conclusions This observational 2a development study demonstrates the safety of a novel approach to the early detection of AL from extraperitoneal colorectal anastomoses. The technique requires validation in a larger cohort and a multicentre study is planned to investigate the efficacy of GG rectal tube flushes as an early biomarker of AL in low pelvic anastomoses. What does this paper add to the literature? This paper assesses rectally administered Gastrografin (GG) as a novel drain fluid biomarker of anastomotic leak (AL). Few studies have investigated the extravasation of intraluminal substances. Intuitively, these are more likely to lead to the diagnosis of AL verses those that simply predict the possibility of a leak.

Patients with colorectal cancer undergo frequent diagnostic imaging to stage the extent of metastatic disease and assess response to treatment. Imaging is typically via diagnostic contrast-enhanced CT or combined FDG-PET/CT. However, recent research has demonstrated promising benefits of combined FDG-PET/MRI in oncologic imaging due to the superior soft-tissue contrast of MRI. The extent of both intrahepatic and extrahepatic disease is important in establishing treatment options for colorectal cancer patients, and FDG-PET/CT and dedicated liver imaging are often both required. FDG-PET/MRI offers the advantage of a single examination which can be completed within a similar duration as dedicated liver MRI imaging. This improves patient convenience and anatomical co-registration between PET and MRI imaging and provides a potential cost benefit. The diagnostic benefits of FDG-PET/MRI include the simultaneous characterisation of focal liver lesions, exclusion of extrahepatic disease, the detection of additional hepatic metastases and extrahepatic disease, and the multi-parametric assessment of treatment response. This pictorial review highlights examples of these benefits.