Hyperspectral imaging (HSI) is a novel optical imaging modality, which has recently found diverse applications in the medical field. HSI is a hybrid imaging modality, combining a digital photographic camera with a spectrographic unit, and it allows for a contactless and non-destructive biochemical analysis of living tissue. HSI provides quantitative and qualitative information of the tissue composition at molecular level in a contrast-free manner, hence making it possible to objectively discriminate between different tissue types and between healthy and pathological tissue. Over the last two decades, HSI has been increasingly used in the medical field, and only recently it has found an application in the operating room. In the last few years, several research groups have used this imaging modality as an intraoperative guidance tool within different surgical disciplines. Despite its great potential, HSI still remains far from being routinely used in the daily surgical practice, since it is still largely unknown to most of the surgical community. The aim of this study is to provide clinical surgeons with an overview of the capabilities, current limitations, and future directions of HSI for intraoperative guidance.
Background and aims: Anastomotic biliary stricture (ABS) is the most common biliary complication after orthotopic liver transplantation (OLT) and can be successfully managed endoscopically. The long-term results of a protocol using placement of multiple plastic stents to treat ABS following OLT were analyzed. Methods: All patients who underwent endoscopic retrograde cholangiopancreatography (ERCP) for OLT-related biliary complications at our Endoscopy Unit between July 1994 and March 2012 were retrospectively identified from the ERCP database. Patients with an ABS treated with an increasing number of plastic stents were included in the study. Follow-up after stent removal was obtained by telephone contact with the patient and/or referring physician and by liver function tests (LFTs) evaluation. Results: 56 patients, treated with an increasing number of plastic stents until resolution of the stricture, were included. Five patients were then excluded (unrelated death during treatment, n = 3; incomplete treatment because of poor compliance, n = 2), and 51/56 patients reached study end points and were included in the analysis. Resolution of ABS was obtained in 50/51 patients; 1 patient required hepaticojejunostomy because of failure to pass the stricture with the guidewire (per protocol resolution, 98 %). Mean duration of endoscopic treatment was 11.5 months, with a median 4 ERCPs per patient. Immediate ERCP-related adverse events occurred in 3/56 patients (5.4 %). After a median follow-up of 5.8 years from stent removal, 3/50 patients (6 %) had recurrence of ABS. These 3 patients were successfully treated again endoscopically and are asymptomatic after a further median follow-up of 5.6 years. Conclusions: At long-term follow-up, endoscopic treatment with multiple plastic stents of ABS following OLT appeared to be effective in most patients. Stricture recurrence is rare and can be successfully treated again endoscopically.