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Aim The aim of the present work was to perform an up‐to‐date review of the literature on endoluminal negative pressure therapy for colorectal anastomotic leak. Method An electronic search in PubMed and Google Scholar and a manual search without language restrictions were performed on 25 January 2019. Only original series reporting endoluminal negative pressure therapy in colorectal anastomotic leaks were included. The primary outcome was the success rate (complete closure of the abscess cavity). The secondary outcomes were the rates of complications and stoma closure. Results Nineteen series with a total of 295 cases were analysed. The median distance of the anastomosis from the anal verge and the size of the abscess were 5.65 cm (4.9–10) and 6.0 cm (5–8.1) respectively. In 84.5% (78%–91%) the stoma was created at the first intervention. Neoadjuvant therapy was performed in 48.6% (3%–60%). Median 7 sponges (2–34) were used with median negative pressure 150 mmHg (125–700) for a median of 31 days (14–127). The success rate was 85.4% (80%–91%) with ileostomy closure in 72.6%. Complications were observed in 19% (13%–25%): abscesses 11.5% and anastomotic stenosis 4.4%. Laparotomy was required in 15% of the complications. The stoma was the only significant predictor for the success of the therapy (0.007, SE 0.004, P = 0.040). Conclusions The initial experience looks promising with an 85% success rate, which precludes risky re‐resections with redo anastomosis or Hartmann's procedure. Despite the good initial results, definitive conclusions cannot be drawn because of the small sample size and the lack of high‐quality comparative studies.

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Voltage, frequency, and temperature dependences of photo-emf are experimentally studied in the MIS HgCdTe/SiO 2 /Si 3 N 4 and HgCdTe/АОF structures. The MIS structures were produced on the basis of graded-bandgap Hg 1-x Cd x Te films grown by molecular-beam epitaxy on GaAs substrates. It is found that the subsurface graded-band-gap layers do affect the photoelectrical characteristics of MIS structures. The mechanisms limiting the differential resistance in the space-charge region at various temperatures are revealed.The narrow-gap solid solution Hg x Cd 1-x Te (MCT) is a basic material for producing highly sensitive IR detectors operating in the spectral ranges of atmospheric windows 3-5 and 8-12 μm [1-3]. The HgCdTe band-gap width depends on the mercury/cadmium ratio in the solid solution, which allows one to optimize the HgCdTe detector characteristics for various spectral ranges. Molecular-beam epitaxy (MBE) provides for producing HgCdTe films with specified depthdistribution profiles of native components and impurities. Interest in MIS structures based on graded-band-gap epitaxial HgCdTe is due to the necessity to passivate the surfaces of the HgCdTe photodiode arrays and to additional possibilities such graded-band-gap structures offer for developing monolithic detectors. A number of papers are concerned with studying the properties of MIS structures based on bulk HgCdTe [2][3][4][5]. However, the electrophysical and photoelectrical properties of MIS structures based on graded-band-gap epitaxial HgCdTe are still not understood though these structures must have a number of special features due to the presence of subsurface graded-band-gap layers and high resistance of the epitaxialfilm volume because of small film thickness (usually less than 10 μm). The results of investigations into the electrophysical characteristics of graded-band-gap MBE HgCdTe are published in [6][7][8][9]. Some preliminary results of examination of the voltage dependence of photo-emf are reported in [10]. In this paper, we discuss the results of experimental studies of photoemf versus voltage, light-flux modulation frequency, and temperature for the MIS structures based on graded-band-gap MBE HgCdTe (x = 0.21-0.23). MIS STRUCTURE TECHNOLOGY AND MEASURING TECHNIQUESThe MIS structures under study were produced on the basis of HgCdTe of the p-(x = 0.22) and n-(x = 0.21-0.32) types of conductivity grown by molecular-beam epitaxy on the GaAs (013) substrates. While growing the heterostructures, the graded-band-gap layers with enhanced composition of CdTe (the thickness of a subsurface graded-band-gap layer was 0.5-0.7 μm, the subsurface composition being as high as x = 0.43-0.48) were produced on both sides of a 7.7-8.3 μm thick working layer of composition x = 0.21-0.32. Before dielectric coating, the majority charge-carrier concentration n(p) and mobility μ, as well as the film conductivity σ were measured by the Hall method. The minority charge-carrier lifetime was determined by the method of photosignal relaxation using a contactless mi...