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Background: In recent years the focus on practical skills in the German curriculum of medical school has increased greatly. In this study we evaluate the value of a practical surgery course for medical students as a tool for surgical education, as a way of enhancing interest in surgical fields, and as a method of influencing medical students to subsequently choose a surgical career., Methods: The "Feel like a surgeon"-course is an optional practical surgery course in which topographical anatomy and realistic surgical training using fresh human cadavers are combined for medical students of the RWTH Aachen University. Between 2010 and 2015 every student completed a survey before starting and after completing our course, and in 2015 a follow-up was performed. Using a standardized questionnaire, course quality, learning success and impact on post-instructional career and choice of profession was evaluated., Results: In total, 82 students attended our course between 2010 and 2015 and took part in the evaluation. Evaluation of the course was positive overall, with an average grade of 1.4° ± °0.50. Significant improvement of basic, as well as more complex surgical skills and theoretical knowledge was noted. Furthermore, self-confidence for patient related assignments improved as well. In the follow-up evaluation, a high level of recommendation for surgical residents was seen, as was a high influence of the course on our students' career choice, although no significant change in career plans before and after taking the course was noted., Conclusions: Our results indicate that a practical surgical course can be a valuable tool to prepare students for a surgical residency and to improve their practical skills generally.

Chemokines mediate monocyte adhesion to dysfunctional endothelial cells (ECs) and promote arterial inflammation during atherosclerosis. Hypoxia-inducible factor (HIF)-1α is expressed in various cell types of atherosclerotic lesions and is associated with lesional inflammation. However, the impact of endothelial HIF-1α in atherosclerosis is unclear. HIF-1α was detectable in the nucleus of ECs covering murine and human atherosclerotic lesions. To study the role of endothelial HIF-1α in atherosclerosis, deletion of the Hif1a gene was induced in ECs from apolipoprotein E knockout mice (EC-Hif1a(-/-)) by Tamoxifen injection. The formation of atherosclerotic lesions, the lesional macrophage accumulation, and the expression of CXCL1 in ECs were reduced after partial carotid ligation in EC-Hif1a(-/-) compared with control mice. Moreover, the lesion area and the lesional macrophage accumulation were decreased in the aortas of EC-Hif1a(-/-) mice compared with control mice during diet-induced atherosclerosis. In vitro, mildly oxidized low-density lipoprotein or lysophosphatidic acid 20:4 increased endothelial CXCL1 expression and monocyte adhesion by inducing HIF-1α expression. Moreover, endothelial Hif1a deficiency resulted in downregulation of miR-19a in atherosclerotic arteries determined by microRNA profiling. In vitro, HIF-1α-induced miR-19a expression mediated the upregulation of CXCL1 in mildly oxidized low-density lipoprotein-stimulated ECs. These results indicate that hyperlipidemia upregulates HIF-1α expression in ECs by mildly oxidized low-density lipoprotein-derived unsaturated lysophosphatidic acid. Endothelial HIF-1α promoted atherosclerosis by triggering miR-19a-mediated CXCL1 expression and monocyte adhesion, indicating that inhibition of the endothelial HIF-1α/miR-19a pathway may be a therapeutic option against atherosclerosis., (© 2015 American Heart Association, Inc.)

Study Design: We present a monocentric analysis of the lumbar artery compression syndrome (LACS) in the form of a case report., Objectives: Literature information was collected about the symptoms, diagnosis and treatment of this rare disorder in the context of the existing data., Methods: The current medical literature includes only one report about three cases of LACS, collected over 20 years in France and Germany. We compared these cases with the experience of the European Vascular Center Aachen-Maastricht., Results: The symptoms of this rare disorder are dominated by reversible, motion-dependent paralysis of the legs. Compression of the right lumbar arteries by muscular fibres or connective tissue is a fundamental cause., Conclusion: Surgical treatment, which means decompression of the lumbar arteries via a thoracolaparotomy, is an appropriate therapy with few complications and good long-term results., (Georg Thieme Verlag KG Stuttgart · New York.)

Background: Porcine models are well established for studying intestinal anastomotic healing. In this study, we aimed to clarify the anatomic differences between human and porcine small intestines. Additionally, we investigated the influences of longitudinal and circular sutures on human small intestine perfusion., Methods: Intestines were obtained from human cadavers (n = 8; small intestine, n = 51) and from pigs (n = 10; small intestine, n = 60). Vascularization was visualized with mennige gelatin perfusion and high-resolution mammography. Endothelial cell density was analyzed with immunohistochemistry and factor VIII antibodies. We also investigated the influence of suture techniques (circular anastomoses, n = 19; longitudinal sutures, n = 15) on vascular perfusion., Results: Only human samples showed branching of mesenteric vessels. Compared to the pig, human vessels showed closer connections at the entrance to the bowel wall (p = 0.045) and higher numbers of intramural anastomoses (p < 0.001). Porcine main vessels formed in multifilament-like vessel bundles and displayed few intramural vessel anastomoses. Circular anastomoses induced a circular perfusion defect at the bowel wall; longitudinal anastomoses induced significantly smaller perfusion defects (p < 0.001). Both species showed higher vascular density in the jejunum than in the ileum (p < 0.001). Human samples showed similar vascular density within the jejunum (p = 0.583) and higher density in the ileum (p < 0.001) compared to pig samples., Conclusion: The results showed significant differences between human and porcine intestines. The porcine model remains the standard for studies on anastomotic healing because it is currently the only viable model for studying anastomosis and wound healing. Nevertheless, scientific interpretations must consider the anatomic differences between humans and porcine intestines.

A common reason for painful lesions of the popliteal fossa are baker's cysts. An important differential diagnosis is the popliteal artery aneurysm, which is rare, but is associated with severe complications. The preferred method of diagnosis is the colour-coded duplex ultrasound. By showing the case of a 58-year-old man, who experienced life-threatening complications caused by an insufficient diagnosis before the operation of a Baker's cyst, we want to underline the importance of preoperative duplex ultrasound diagnosis in this context., (© Georg Thieme Verlag KG Stuttgart · New York.)

Rationale: Chemokine-controlled arterial leukocyte recruitment is a crucial process in atherosclerosis. Formyl peptide receptor 2 (FPR2) is a chemoattractant receptor that recognizes proinflammatory and proresolving ligands. The contribution of FPR2 and its proresolving ligand annexin A1 to atherosclerotic lesion formation is largely undefined., Objective: Because of the ambivalence of FPR2 ligands, we here investigate the role of FPR2 and its resolving ligand annexin A1 in atherogenesis., Methods and Results: Deletion of FPR2 or its ligand annexin A1 enhances atherosclerotic lesion formation, arterial myeloid cell adhesion, and recruitment. Mechanistically, we identify annexin A1 as an endogenous inhibitor of integrin activation evoked by the chemokines CCL5, CCL2, and CXCL1. Specifically, the annexin A1 fragment Ac2-26 counteracts conformational activation and clustering of integrins on myeloid cells evoked by CCL5, CCL2, and CXCL1 through inhibiting activation of the small GTPase Rap1. In vivo administration of Ac2-26 largely diminishes arterial recruitment of myeloid cells in a FPR2-dependent fashion. This effect is also observed in the presence of selective antagonists to CCR5, CCR2, or CXCR2, whereas Ac2-26 was without effect when all 3 chemokine receptors were antagonized simultaneously. Finally, repeated treatment with Ac2-26 reduces atherosclerotic lesion sizes and lesional macrophage accumulation., Conclusions: Instructing the annexin A1-FPR2 axis harbors a novel approach to target arterial leukocyte recruitment. With the ability of Ac2-26 to counteract integrin activation exerted by various chemokines, delivery of Ac2-26 may be superior in inhibition of arterial leukocyte recruitment when compared with blocking individual chemokine receptors., (© 2014 American Heart Association, Inc.)

The CD154-CD40 receptor complex plays a pivotal role in several inflammatory pathways. Attempts to inhibit the formation of this complex have resulted in systemic side effects. Downstream inhibition of the CD40 signaling pathway therefore seems a better way to ameliorate inflammatory disease. To relay a signal, the CD40 receptor recruits adapter proteins called tumor necrosis factor receptor-associated factors (TRAFs). CD40-TRAF6 interactions are known to play an essential role in several inflammatory diseases. We used in silico, in vitro, and in vivo experiments to identify and characterize compounds that block CD40-TRAF6 interactions. We present in detail our drug docking and optimization pipeline and show how we used it to find lead compounds that reduce inflammation in models of peritonitis and sepsis. These compounds appear to be good leads for drug development, given the observed absence of side effects and their demonstrated efficacy for peritonitis and sepsis in mouse models.

Background: Despite medical treatment, one third of patients with uncomplicated type B aortic dissections experience severe late complications. The aim of this study was to identify patients at high risk of mortality during follow-up., Methods: A total of 183 patients with acute Stanford type B dissection were treated in one of the university hospitals (Aachen [Germany], Maastricht [The Netherlands], and Innsbruck [Austria]) between 1997 and 2010. Records indicated that 120 patients were treated conservatively. Of these patients, 16 were lost to follow-up. The maximum diameter, extent of the dissection, and patency of the side branches were determined from computed tomography angiography data. Survival and treatment failure were analyzed by univariate and multivariate Cox regression analysis. The univariate analysis investigated the influence of aortic diameter (≥41 vs <41 mm) on survival, and the multivariate analysis investigated the influence of aortic diameter, age, sex, and surgery on survival., Results: During the follow-up period, the initial treatment was converted to surgical treatment in 21 patients (20.2%). Sixteen of the 104 patients (15.4%) died after a mean of 845.5±805.9 days. The mean maximum aortic transversal diameter at admission was 41.2±8.7 mm. The multivariate analysis identified aortic diameter (P=.004; hazard ratio, 1.07) and age (P=.038; hazard ratio, 1.05) as risk factors that significantly reduce survival., Conclusions: Our study revealed both early aortic dilatation and older age as risk factors for increased mortality after conservative treatment of type B dissection., (Copyright © 2014 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.)

The post-thrombotic syndrome (PTS), long-term sequelae of a deep vein thrombosis (DVT), reduces quality of life and is of great socio-economic importance. Despite conservative treatment which does not directly facilitate recanalization more than 25% of patients develop PTS. Early thrombus removal may decrease the incidence and severity of PTS. Although the evidence for surgical thrombectomy is weak which allows an early and rapid recanalization, this therapy appears to reduce the risk of PTS and iliofemoral thrombosis. Systemic thrombolysis can reduce the incidence of PTS but it is no longer recommended due to serious bleeding complications. Previous studies with new endovascular catheter-guided procedures allowing local application of thrombolysis and thrombus aspiration displayed promising results. However, so far one prospective randomised study (CaVent study) with long-term results has revealed a significant reduction of PTS. The current evidence recommends early thrombus removal for patients at high risk for PTS. New endovascular procedures such as catheter-guided thrombolysis allow rapid thrombus removal but more prospective randomised studies are necessary to ensure the long-term success of this therapy., (Georg Thieme Verlag KG Stuttgart · New York.)

In acute hepatic failure auxiliary liver transplantation is an interesting alternative approach. The aim is to provide a temporary support until the failing native liver has regenerated.(1-3) The APOLT-method, the orthotopic implantation of auxiliary segments- averts most of the technical problems. However this method necessitates extensive resections of both the native liver and the graft.(4) In 1998, Erhard developed the heterotopic auxiliary liver transplantation (HALT) utilizing portal vein arterialization (PVA) (Figure 1). This technique showed promising initial clinical results.(5-6) We developed a HALT-technique with flow-regulated PVA in the rat to examine the influence of flow-regulated PVA on graft morphology and function (Figure 2). A liver graft reduced to 30 % of its original size, was heterotopically implanted in the right renal region of the recipient after explantation of the right kidney.  The infra-hepatic caval vein of the graft was anastomosed with the infrahepatic caval vein of the recipient. The arterialization of the donor's portal vein was carried out via the recipient's right renal artery with the stent technique. The blood-flow regulation of the arterialized portal vein was achieved with the use of a stent with an internal diameter of 0.3 mm. The celiac trunk of the graft was end-to-side anastomosed with the recipient's aorta and the bile duct was implanted into the duodenum. A subtotal resection of the native liver was performed to induce acute hepatic failure. (7) In this manner 112 transplantations were performed. The perioperative survival rate was 90% and the 6-week survival rate was 80%. Six weeks after operation, the native liver regenerated, showing an increase in weight from 2.3±0.8 g to 9.8±1 g. At this time, the graft's weight decreased from 3.3±0.8 g to 2.3±0.8 g. We were able to obtain promising long-term results in terms of graft morphology and function. HALT with flow-regulated PVA reliably bridges acute hepatic failure until the native liver regenerates.

The complement anaphylatoxin C5a functions through its two receptors, C5aR (CD88) and C5a receptor-like 2 (C5L2). Their role in atherosclerosis is incompletely understood. We, therefore, analyzed C5aR and probed the yet unknown expression and function of C5L2 in human atherogenesis. Human atherosclerotic plaques obtained by endarterectomy were staged and analyzed for C5L2 and C5aR by IHC and quantitative real-time PCR. C5L2-expressing cells in plaques were mostly macrophages, less neutrophils and endothelial cells, as determined by double immunostaining. Although early influx of C5aR(+) cells was detected, C5L2 levels increased with lesion complexity and colocalized with C5aR and oxidized low-density lipoprotein. Gene expression of C5L2 and C5aR showed similar trends, such as the receptor-expressing cells. The expression of C5L2 in advanced lesions correlated with increased levels of IL-1β and tumor necrosis factor-α in plaques. Furthermore, in vitro experiments in macrophages from wild-type and C5l2- and C5ar-deficient mice corroborated the contributing role of C5l2 in oxidized low-density lipoprotein-pretreated C5a-induced cytokine expression, as measured by enzyme-linked immunosorbent assay. Finally, C5l2- and C5ar-deficient peripheral blood mononuclear cells showed less arrest on tumor necrosis factor-α-stimulated mouse endothelial cells in vitro when compared with wild-type controls. Taken together, prominent C5L2 expression in advanced atherosclerotic stages directly correlates with high levels of proinflammatory cytokines. This might indicate a proinflammatory role of C5L2 in atherosclerosis that needs to be pursued in the future by applying in vivo mouse models., (Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

Atherosclerosis, a hyperlipidemia-induced chronic inflammatory process of the arterial wall, develops preferentially at sites where disturbed laminar flow compromises endothelial cell (EC) function. Here we show that endothelial miR-126-5p maintains a proliferative reserve in ECs through suppression of the Notch1 inhibitor delta-like 1 homolog (Dlk1) and thereby prevents atherosclerotic lesion formation. Endothelial recovery after denudation was impaired in Mir126(-/-) mice because lack of miR-126-5p, but not miR-126-3p, reduced EC proliferation by derepressing Dlk1. At nonpredilection sites, high miR-126-5p levels in endothelial cells confer a proliferative reserve that compensates for the antiproliferative effects of hyperlipidemia, such that atherosclerosis was exacerbated in Mir126(-/-) mice. In contrast, downregulation of miR-126-5p by disturbed flow abrogated EC proliferation at predilection sites in response to hyperlipidemic stress through upregulation of Dlk1 expression. Administration of miR-126-5p rescued EC proliferation at predilection sites and limited atherosclerosis, introducing a potential therapeutic approach.

Purpose: This study was designed to evaluate CO2 computed tomography angiography (CO2-CTA) of the iliac and lower limb arteries in patients with contraindications for iodinated contrast agent (ICA)., Methods: Five patients with contraindications for ICA were examined using CO2-fluoroscopic enhanced angiography (CO2-FLA) and CO2-CTA using a high-pitch examination protocol. Objective (vessel diameter) and subjective (visual score) image quality parameters were evaluated. Pathological findings in both modalities were compared., Results: CO2-CTA was feasible in all patients without adverse side effects, except for CO2 injection-associated pain. Objective vessel analysis revealed no significant difference in diameters as determined by CO2-CTA and CO2-FLA (0.44 ± 0.4 and 0.46 ± 0.41 mm, p = 0.93). CO2-CTA had on average a higher image-quality score (2.6 ± 1.0 vs. 2.3 ± 1.0, p = 0.009). While for pelvic and upper leg CO2-CTA advantageous (3.1 ± 0.74 vs. 2.7 ± 0.9, p = 0.0014) at good quality scores, for calf vessels no significant improvement was visible (1.9 ± 1.0 vs. 1.7 ± 0.9, p = 0.49) and scores were poorer., Conclusions: CO2-CTA with high-pitch CT was feasible in a limited number of patients. Image-quality scores were on average higher for CO2-CTA than for CO2-FLA, while limited imaging quality in the vessels below the knee needs further work on the CT protocol. An added value of cross-sectional imaging was apparent but needs further quantification.

Recruitment of neutrophils, regarded as a key mechanism in acute lung injury (ALI), is orchestrated by cell adhesion molecules and chemokines. While the importance of cell adhesion molecules has been carefully investigated, little is known about the importance of chemokines and their receptors in the recruitment of neutrophils in models of ALI. Wild-type Ccr2(-/-), Ccr5(-/-), Fpr1(-/-) or Fpr2(-/-) mice were exposed to aerosolized lipopolysaccharide and the number of neutrophils in the lung tissue (intravascular, interstitial) and in the bronchoalveolar lavage was quantified. Lack of CCR5 or FPR1, but not CCR2 or FPR2, significantly reduced lung neutrophil infiltration in all compartments. Similarly, blockade of CCR5 or FPR1 with specific antagonists reduced counts of alveolar, interstitial and intravascular neutrophils. Such treatments also inhibited lung edema formation and histological lung tissue alterations, thus underscoring the protective role of CCR5 and FPR1 neutralizing strategies in ALI., (Copyright © 2013 S. Karger AG, Basel.)

Background: Iliofemoral deep venous thrombosis (DVT) is associated with a high incidence of the post-thrombotic syndrome. The current CHEST guidelines suggest that catheter-directed thrombolysis can be used for patients with acute iliofemoral DVT and severe leg complaints. Current literature shows that catheter-directed thrombolysis increases patency of the affected tract and may reduce post-thrombotic complications, but treatment time and bleeding complications are high. Ultrasound-accelerated catheter-directed thrombolysis (UACDT) uses ultrasound waves to enhance clot lysis, which should lower treatment time and bleeding complications with the same or higher patency rates. We report our clinical experience with UACDT on patency and complications in patients with acute iliofemoral DVT., Methods: Patients treated with UACDT for acute iliofemoral DVT were included in our analyses. Diagnosis of iliofemoral DVT was confirmed using duplex sonography and magnetic resonance venography. In addition to thrombolysis, stents were placed or an arteriovenous fistula was created to ensure patency of the treated vein, if indicated. The main outcome is patency after 1 year. Secondary outcome measures are treatment time, bleeding complications, and pulmonary embolism. Patency was assessed using duplex sonography., Results: In total, 37 patients (average age at intervention, 42 years; range, 5-76 years) were included. The DVT location was unilateral in 33 patients (20 left side, 13 right side), and four were bilateral. The average treatment time was 43 ±17 hours. The success rate of thrombolysis was 95% (n = 35); re-thrombosis occurred in 11 (30%) patients. Major bleeding occurred in one patient (3%), and three minor bleedings occurred at the insertion side of the catheter (8%). One pulmonary embolism was encountered (3%). One patient had fever with positive blood cultures for Staphylococcus aureus. Additional procedures were required in 54% (n = 20) of patients. Primary patency was 70% at 1 year; secondary patency was 87% after 1-year follow up., Conclusions: UACDT of acute iliofemoral DVT is feasible and safe. Supplementary percutaneous transluminal angioplasty and stenting play an important role in preventing re-thrombosis., (Copyright © 2013 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

The COP9 signalosome (CSN), a multifunctional protein complex involved in the regulation of cullin-RING-E3 ubiquitin ligases (CRLs), has emerged as a regulator of NF-κB signalling. As NF-κB drives the expression of pro-inflammatory and pro-atherosclerotic genes, we probed the yet unknown role of the CSN, in particular CSN5, on NF-κB-mediated atherogenic responses in endothelial cells. Co-immunoprecipitation in human umbilical vein endothelial cells (HUVECs) revealed the presence of a super-complex between IKK and CSN, which dissociates upon TNF-α stimulation. Furthermore, CSN5 silencing enhanced TNF-α-induced IκB-α degradation and NF-κB activity in luciferase reporter assays. This was paralleled by an increased NF-κB-driven upregulation of atherogenic chemokines and adhesion molecules, as measured by qPCR and flow cytometry, and translated into an enhanced arrest of THP-1 monocytes on TNF-α-stimulated, CSN5-depleted HUVECs. Reverse effects on NF-κB activity and THP-1 arrest were seen upon CSN5 overexpression. Finally, double-immunostaining confirmed the expression of CSN subunits in the endothelium of human atherosclerotic lesions, and revealed an increased expression of CSN5 which correlated with atheroprogression. In conclusion, endothelial CSN5 attenuates NF-κB-dependent pro-inflammatory gene expression and monocyte arrest on stimulated endothelial cells in vitro, suggesting that CSN5 might serve as a negative regulator of atherogenesis.

Background: As one of the primary etiologies of the post-thrombotic syndrome, chronic venous occlusion is a huge burden on patient quality of life and medical costs. In this study, we evaluate the short-term and midterm results of endovenous recanalization by angioplasty and stenting in chronic iliofemoral deep venous occlusions., Methods: This is a retrospective observational study set in a tertiary medical referral center. Patients with venous claudication or C4-6 venous disease combined with duplex and magnetic resonance-confirmed iliofemoral or caval occlusion were included. Patients with recent deep vein thrombosis (<1 year) were excluded. The intervention was endovascular deep venous recanalization, followed by angioplasty and stenting. Safety and feasibility were clinically evaluated during the procedure and during follow-up. Reocclusions and other treatment failures were evaluated during a maximum follow-up of 31 months by ultrasound imaging and venography., Results: Seventy-five procedures were performed in 63 patients (average age, 44 years; range, 18-75 years), of whom 86% had a history of deep venous thrombosis. The mean time between the initial deep venous thrombosis and treatment with PTA and stenting was 12 years (maximum, 31 years). May-Thurner syndrome was present in 57%. Forty-two procedures were performed in the left, six in the right, and 11 in both lower extremities. The vena cava inferior was partially stented in 25 patients. An average of 2.6 stents (median, 2) were used per procedure. Primary patency was 74% after 1 year. Assisted primary and secondary patency rates were 81% and 96%, respectively, at 1 year. Secondary procedures included restenting, catheter-directed thrombolysis, endophlebectomy of the common femoral vein, and creation of an arteriovenous fistula. No clinically evident pulmonary emboli were noted. A bleeding complication occurred after six procedures and was deemed major in two. No patients died. Relief or significant improvement of symptoms of chronic venous occlusive disease was achieved in 81% of patients., Conclusions: Endovenous recanalization by angioplasty and stenting of chronically occluded iliofemoral vein segments is a safe and effective treatment with good short-term results, even when treatment takes place decades after the initial deep venous thrombosis. Most reocclusions can be adequately treated by a secondary procedure., (Copyright © 2013 Society for Vascular Surgery. Published by Elsevier Inc. All rights reserved.)

Purpose: To systematically investigate the impact of image acquisition and contrast injection parameters for CO2-enhanced CT angiography (CTA) of the aorto-iliac and peripheral arteries in a pig model using commercially available equipment. The aim was to establish an imaging protocol that is ready for use in human subjects., Materials and Methods: Three domestic swine underwent CO2-CTA with varying injection parameters: pitch (1.0, 3.0), injection pressure (0.7 bar, 1.0 bar, 1.3 bar) and scan delay (2 s, 4 s, 6 s). Objective (vessel diameter) and subjective (image quality) parameters and applied radiation doses were systematically evaluated. To ensure clinical applicability of the setting, only approved catheters/injectors and standard injection parameters were evaluated., Results: The image quality scores were superior and the vessel diameter was larger with high pitch in comparison to standard pitch (diameters: 4.7 ± 2.0 mm vs. 3.6 ± 2.1 mm, p = 0.0040, scores: 2.6 ± 1.1 vs. 2.0 ± 1.1, p = 0.0038). High injection pressure (1.3 bar) improved the image quality as assessed by subjective and objective ratings (diameters: 3.6 ± 2.0 mm, 4.0 ± 2.1 mm and 4.6 ± 2.1 mm, for 0.7, 1.0 and 1.3 bar, p-values ≤ 0.0052, scores: 1.9 ± 1.1, 2.3 ± 1.1 and 2.7 ± 1.2, p-values ≤ 0.0017), the same was observed for a shorter injection delay (diameters: 3.5 ± 2.0 mm, 4.2 ± 2.1 mm and 4.8 ± 2.1 mm, for 6 s, 4 s, and 2 s, p ≤ 0.0022, scores: 1.9 ± 1.1, 2.3 ± 1.1 and 2.7 ± 1.1, p-values ≤ 0.0013). The dose length products were 239 ± 47 mGycm (high pitch) and 565 ± 63 mGycm (standard pitch, p-values < 0.0001)., Conclusion: A higher pitch, shorter delay and higher injection pressure improve image quality in CO2-enhanced CTA. Since commercially available, clinically approved equipment was used. The protocol is now ready for use in human subjects., (© Georg Thieme Verlag KG Stuttgart · New York.)

Purpose: If a colonic or small bowel lesion is not accessible for endoscopic mucosal resection, enterotomy is a possible although rarely performed surgical technique. It has never been compared to circular anastomosis regarding leakage rate, bowel wall perfusion, and wound healing. Thus, the aim of this basic experimental scientific study was to investigate perianastomotic microcirculation and wound healing., Methods: Forty rats were divided into four groups (1 jejunal anastomosis, 2 jejunal enterotomy, 3 colonic anastomosis, and 4 colonic enterotomy). Following anastomosis and enterotomy, the intestinal perfusion was measured using laser fluorescence angiography (IC-View). On postoperative day 7, the surface of the mucosal villi, expression of matrix metalloproteinases (MMP) 2, 8, 9, and 13, and the number of proliferating cells (Ki67) as well as the collagen types I/III ratio were analyzed., Results: The perianastomotic microperfusion was significantly reduced in all groups compared to the reference region. The perianastomotic perfusion index was significantly reduced in group 1 compared with group 2, whereas the perfusion index in group 3 was slightly but not significantly reduced in comparison to group 4. Ki67 was elevated in both circular anastomosis groups. Surface of the mucosal villi, MMP expression, and collagen type I/III ratio revealed no significant differences., Conclusions: Our study affirms the theoretical consideration of a better microperfusion of the bowel wall following an antimesenterial enterotomy and demonstrates that enterotomy is not inferior compared to circular anastomosis. Even though enterotomy is a rarely used surgical technique, it should be regarded as a possible alternative in particular situations.

Background: The endovascular treatment of abdominal aortic aneurysms has become more common. A careful comparison of this technique with the established treatment by open surgery is needed before it can be more widely adopted., Methods: We selectively searched the Medline database for articles on the endovascular treatment of abdominal aortic aneurysms, with special attention to prospective, randomized trials comparing it to open aortic surgery (keywords: "endovascular abdominal aortic repair" and "prospective randomized trial")., Results: Data on 30-day mortality and long-term survival are now available from four randomized multicenter trials. In three of these trials, endovascular treatment was found to lower 30-day mortality by two-thirds (endovascular: 0.2% to 1.7%, open repair: 0.7% to 4.7%), but this difference in survival was no longer present at two years. Compared to open open aortic surgery, endovascular treatment has a higher long-term complication rate. Endoleakage (perigraft leakage) accounted for more than 30% of complications and was the commonest reason for reintervention and unsuccessful intervention; in nearly all cases, it was successfully treated by the endovascular route. The rate of secondary aortic rupture was 0.8%, and migration of the prosthesis occurred in 5% of cases. Follow-up checks of the stent graft are now recommended at 3, 6 and 12 months after implantation, and annually thereafter., Conclusion: Prospective randomized trials have shown that the endovascular technique lowers perioperative mortality. In the long term, however, it has a higher complication rate than open aortic surgery and leads to more frequent reintervention.

Aim: The aim of this study was to assess if chronic intermittent pressure of a thoracoabdominal aortic aneurysm (TAAA) induces structural changes in vertebral bodies and if eroded vertebral bones can still be found after the extermination of syphilis., Methods: A retrospective analysis of computed tomography (CT) scans of patients with TAAA was performed. In the anatomical regions were the TAAA was in close contact with the vertebral bodies, the vertebral body alteration was distinguished into 4 categories. Category 0: no changes; 1: discrete changes, minimal asymmetry; 2: obvious asymmetry of the vertebral body with sustained cortical layer; 3: severe destruction of the vertebral body with loss of the cortical layer., Results: Eighty-six CT scans of patients (mean age 63; range 25-82 years) with TAAA pathology were examined (24 female, 62 male). The mean aneurysm diameter was 6.5 cm (4.3-14 cm). The results for scoring were: category 0: 33 patients; category 1: 46 patients; category 2: 5 patients and category 3: 2 patients. One of the category 3 patients suffered from acute spinal cord compression with complete paraplegia. In total, 62% of patients showed some degree of changes at vertebral bodies adjacent to the TAAA., Conclusion: Intermittent pressure by either dissecting or non-dissecting TAAAs may induce structural changes in the vertebral bodies of the spine. Severe destruction of the bone is a rare, but existing complication.

Neointimal hyperplasia is one the primary causes of stenosis in arterialized veins that are of great importance in arterial coronary bypass surgery, in peripheral arterial bypass surgery as well as in arteriovenous fistulas.(1-5) The experimental procedure of vein graft interposition in the common carotid artery by using the cuff-technique has been applied in several research projects to examine the aetiology of neointimal hyperplasia and therapeutic options to address it. (6-8) The cuff prevents vessel anastomotic remodeling and induces turbulence within the graft and thereby the development of neointimal hyperplasia. Using the superior caval vein graft is an established small-animal model for venous arterialization experiment.(9-11) This current protocol refers to an established jugular vein graft interposition technique first described by Zou et al., (9) as well as others.(12-14) Nevertheless, these cited small animal protocols are complicated. To simplify the procedure and to minimize the number of experimental animals needed, a detailed operation protocol by video training is presented. This video should help the novice surgeon to learn both the cuff-technique and the vein graft interposition. Hereby, the right external jugular vein was grafted in cuff-technique in the common carotid artery of 21 female Sprague Dawley rats categorized in three equal groups that were sacrificed on day 21, 42 and 84, respectively. Notably, no donor animals were needed, because auto-transplantations were performed. The survival rate was 100 % at the time point of sacrifice. In addition, the graft patency rate was 60 % for the first 10 operated animals and 82 % for the remaining 11 animals. The blood flow at the time of sacrifice was 8±3 ml/min. In conclusion, this surgical protocol considerably simplifies, optimizes and standardizes this complicated procedure. It gives novice surgeons easy, step-by-step instruction, explaining possible pitfalls, thereby helping them to gain expertise fast and avoid useless sacrifice of experimental animals.

Treatment of acute lung injury (ALI) remains an unsolved problem in intensive care medicine. Activation and recruitment of neutrophils are regarded as key mechanisms in the progression of ALI. As pioglitazone holds potent pleiotropic anti-inflammatory effects, we explored its effects during ALI. C57Bl/6 mice were exposed to aerosolised lipopolysaccharides (LPSs) (500 μg·mL(-1)) and their alveolar, interstitial and intravascular neutrophils were assessed 4 h later. Lung permeability changes were evaluated by fluorescein isothiocyanate-dextran clearance and protein content in the bronchoalveolar lavage fluid. In vitro, human isolated neutrophils were pretreated with piolitazone (10 μM, for 1 or 3 h) and then activated with N-formyl-L-methionyl-L-leucyl-L-phenylalanine. Neutrophil activation, adhesion, release and formation of reactive oxygen species (ROS) and phagocytosis were measured thereafter. Pioglitazone treatment before or after induction of ALI significantly diminished alveolar (reduction by 73% and 67%, respectively) and interstitial neutrophil influx (reduction by 55% and 63%, respectively) and reduced lung permeability changes (reduction by 64% and 58%, respectively) indicating a protective role of pioglitazone treatment in ALI. Moreover, pioglitazone significantly reduced degranulation and adhesion of neutrophils without affecting ROS formation and release or bacterial phagocytosis. Pioglitazone reduces recruitment and activation of neutrophils thereby preventing LPS-induced ALI. Our results imply a potential role for pioglitazone treatment in the management of ALI.

Objective: This study assessed the feasibility and effectiveness of remote neuromonitoring as an adjunct to spinal cord protection during surgical repair of descending thoracic aortic aneurysms and thoracoabdominal aortic aneurysms., Methods: Four aortic centers in three European countries participated in this prospective observational study. A similar surgical protocol was used in all centers, including assessment of spinal cord function by means of monitoring motor-evoked potentials (MEPs). MEP information was evaluated at one central neurophysiologic department in Maastricht, The Netherlands. Transfer of MEP data from all operating rooms to Maastricht was arranged by Internet connections. In all patients, the protective and surgical strategies to prevent paraplegia were based on MEPs. The on-site surgeons reacted in real time to the interpretation and feedback of the neurophysiologist., Results: Between March 2009 and May 2011, 130 patients (85 men) were treated by open surgical repair. Extent of aneurysms was equally distributed among the centers. Neuromonitoring was technically stabile and successful in all patients. The transfer of data from the operating room in the different vascular centers was undisturbed and without any technical problems. By maintaining a mean distal aortic pressure of 60 mm Hg, MEPs were undisturbed in 65 patients (50%). In another 65 patients (50%), significant changes in MEPs prompted the surgical teams to initiate additional protective and surgical strategies to restore spinal cord perfusion. These measures were not effective in five patients (3.8%), and acute paraplegia resulted. Delayed paraplegia occurred in 10 patients (7.7%) but improved in three and recovered completely in another three. No false-negative or false-positive MEP recordings were experienced., Conclusions: Remote neuromonitoring of spinal cord function during open repair of descending thoracic aortic aneurysms and thoracoabdominal aortic aneurysms as a telemedicine technique is feasible and effective. It allows centralization of expertise and saves individual centers from investing in complex technology. The value of monitoring MEPs was confirmed in different aortic centers, resulting in adequate neurologic outcome after extensive aortic surgical procedures., (Copyright © 2012 Society for Vascular Surgery. Published by Mosby, Inc. All rights reserved.)

Introduction: Treatment of acute lung injury (ALI) remains an unsolved problem in intensive care medicine. As simvastatin exerts protective effects in inflammatory diseases we explored its effects on development of ALI and due to the importance of neutrophils in ALI also on neutrophil effector functions., Methods: C57Bl/6 mice were exposed to aerosolized LPS (500 µg/ml) for 30 min. The count of alveolar, interstitial, and intravasal neutrophils were assessed 4 h later by flow cytometry. Lung permeability changes were assessed by FITC-dextran clearance and albumin content in the BAL fluid. In vitro, we analyzed the effect of simvastatin on neutrophil adhesion, degranulation, apoptosis, and formation of reactive oxygen species. To monitor effects of simvastatin on bacterial clearance we performed phagocytosis and bacterial killing studies in vitro as well as sepsis experiments in mice., Results: Simvastatin treatment before and after onset of ALI reduces neutrophil influx into the lung as well as lung permeability indicating the protective role of simvastatin in ALI. Moreover, simvastatin reduces the formation of ROS species and adhesion of neutrophils without affecting apoptosis, bacterial phagocytosis and bacterial clearance., Conclusion: Simvastatin reduces recruitment and activation of neutrophils hereby protecting from LPS-induced ALI. Our results imply a potential role for statins in the management of ALI.

Despite optimal treatment of acute deep-vein thrombosis (DVT) there is a great chance of recurrent DVT and development of post-thrombotic syndrome (PTS) in the long term. The degree of spontaneous recanalization differs per patient and per thrombus location. 90% of all femoropopliteal occlusions will fully recanalize within 1 year; however, in the case of an iliofemoral thrombosis, recanalization occurs only in a minority of cases. Post-thrombotic complications occur more often following iliofemoral thrombosis, and the chance of recurrent thrombosis is greater than following thrombosis in a more distal location. An anatomical variation or abnormality also more often underlies an iliofemoral thrombosis. It is important to identify patients with a greater chance of developing PTS promptly and to treat them in order to prevent post-thrombotic damage. There are still insufficient trial data available to implement catheter-directed thrombolysis as standard therapy for iliofemoral thrombosis

We present the rare case of a false aneurysm of the genus lat which occurred after knee arthroscopy. Apart from a pulse-synchronic swelling in close proximity to the former anterolateral portal there were no complaints and no pain. The diagnostic and therapeutic strategies - in this case performed with coiling of the involved vessel - are presented and discussed., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background: The total rate as well as the clinical outcome of anastomotic leakage in colorectal and coloanal anastomosis necessitates a loop stoma for fecal diversion. The aim of this study was to determine the outcome of loop transverse colostomy compared to loop ileostomy as a temporary defunctioning stoma following colorectal surgery with colorectal or coloanal anastomosis., Methods: Data of 200 patients between January 2003 and January 2009 were analyzed in this two-center study to determine the surgical outcome in patients with loop colostomy (n = 100) in comparison to loop ileostomy (n = 100) for fecal diversion including outcome of stoma creation and complication rates during stoma reversal., Results: During stoma placement, dermatitis and renal insufficiency occurred significantly more often in the loop ileostomy group than in the loop transverse colostomy group (15% vs. 0%; p < 0.001 and 10% vs. 1%; p = 0.005). During stoma reversal, wound infection occurred significantly more often in the loop transverse colostomy group than in the loop ileostomy group (27% vs. 8%; p < 0.001). Time to first defecation was significantly shorter in the loop ileostomy group after both placement and reversal (4 ± 2 vs. 2 ± 1; p < 0.001 and 3 ± 2 vs. 2 ± 1; p < 0.001). Hospital stay was significantly shorter in the loop ileostomy group than in the loop transverse colostomy group after stoma closure (18 ± 15 vs. 13 ± 6; p < 0.001)., Conclusions: Both methods provide a good operative outcome with low complication rates. We do recommend the loop ileostomy in all patients in which dehydration is not to be expected since wound infection rate is lower and hospital stay is shorter during stoma reversal.

Background: In colorectal surgery, anastomotic leakage is a relevant complication. The aim of this study was to investigate whether intraperitoneally (i.p.) administered zinc improves the healing of colon anastomosis in rats., Materials and Methods: Male Wistar rats (66) received zinc-deficient diet for 21 days. To determine the effective dose of zinc which is necessary to compensate this deficiency, preliminary analysis in 30 rats were performed. In these rats, analysis by atom-absorption spectrophotometry revealed a dose of 1.0 mg zinc aspartate/kg body weight to be the compensatory dosage. In the remaining zinc-deficient rats (n= 36), a transverse colonic anastomosis was performed. Eighteen rats received either a zinc supplementation i.p. or 0.9% NaCl i.p. (n = 18; control group). On postoperative days 3, 5, and 14, the surface of the mucosal villi, expression of MMP 2, MMP 8, MMP 13, TIMP 1, as well as the collagen types I/III ratio were analyzed., Results: Protein expression of MMP 2 and MMP 8 was significantly higher in the anastomosis of the zinc group on day 3 and on day 5. The collagen types I/III ratio was significantly increased in the zinc group on days 5 and 14., Conclusion: Balancing zinc deficiency benefits wound healing of colonic anastomosis qualitatively due to an increased collagen type I/III ratio. Surprisingly, these zinc supplements, however, increased the expression of MMP 2 and MMP 8 that are supposed to impair wound healing in case of an over-expression. Thus, further investigations are needed to elucidate the influence of zinc supplementation on regulation of MMPs.

Treatment of acute lung injury (ALI) and its most severe form, acute respiratory distress syndrome (ARDS), remain unsolved problems of intensive care medicine. ALI/ARDS are characterized by lung edema due to increased permeability of the alveolar-capillary barrier and subsequent impairment of arterial oxygenation. Lung edema, endothelial and epithelial injury are accompanied by an influx of neutrophils into the interstitium and broncheoalveolar space. Hence, activation and recruitment of neutrophils are regarded to play a key role in progression of ALI/ARDS. Neutrophils are the first cells to be recruited to the site of inflammation and have a potent antimicrobial armour that includes oxidants, proteinases and cationic peptides. Under pathological circumstances, however, unregulated release of these microbicidal compounds into the extracellular space paradoxically can damage host tissues. This review focuses on the mechanisms of neutrophil recruitment into the lung and on the contribution of neutrophils to tissue damage in ALI.

We present two cases in which displaced proximal humeral fractures are accompanied by vascular injury. These Injuries are very rare but severe and the accompanying vascular impairment can have great clinical consequences. Therefore, we try to emphasize on the importance of thorough and accurate diagnostics, because it is obligatory for early diagnosis and improving the eventual outcome of these injuries. The specific order in treatment (internal fixation first or vascular repair first) depends on the severity of the accompanying vascular injury. The increasing use of endovascular procedures to treat vascular lesions is a very interesting development with several advantages, especially in elderly and multimorbid patients.

Background: The management of small intestinal serosal defects remains controversial. Non-closure of such defects is regarded as a risk factor of fistula formation or intestinal leakage, whereas defect closure with absorbable suture material is potentially associated with adhesion formation. The aim of our pilot study was to evaluate the influence of small intestinal serosal defect closure on peritoneal wound healing, leakage rate, and adhesion formation in a rabbit model., Methods: Twenty-two male rabbits were randomized into two groups. Following median laparotomy, a standardized small intestinal serosal defect with a diameter of 1 cm was performed. Either the defect was closed by two seromuscular 4/0 polyglactin single sutures (n = 11) or the defect was left open (n = 11). On postoperative day 14, all animals were sacrificed for morphological investigations. Complications and the rate of intestinal leakage were measured. The degree of adhesion formation was measured by computer-assisted planimetry., Results: No animal developed fistula formation or intestinal leakage. Eight (73%) animals of the closure group developed local peritoneal adhesions with a mean size of 39.7 ± 45 mm(2). No animal in the non-closure group revealed local peritoneal adhesions at the defect. However, two (18%) animals in the non-closure group developed peritoneal adhesions distant to the defect with a mean size of 3.5 ± 9 mm(2). Comparing both groups, the size of peritoneal adhesions was significantly higher in the closure group (p = 0.013)., Conclusions: Closure of isolated serosal injuries with resorbable suture material was associated with an adhesion formation in distressing certainty, whereas no leakage or fistula formation could be observed at all. Further studies are needed to clarify the impact of serosal defect closure in particular on leakage rate and fistula formation, e.g., with pre-existing adhesions, in case of multiple serosal injuries or with a pre-existing peritonitis.

Marfan Syndrome is a heritable disorder of connective tissue leading to aortic aneurysms and other cardiovascular complications associated with reduced life expectancy. Marfan patients with thoracic aortic aneurysms (TAAs) or with thoracoabdominal aortic aneurysms (TAAAs) should be treated by means of open surgery, requiring an extensive protocol, including extracorporeal circulation, neuromonitoring and adjunctive modalities to provide organ protection. Then, open surgical repair of TAA(A)s are associated with excellent results. However, in the last time a gradual change to endovascular treatment in Marfan patients is observable. Particularly in patients with an increased surgical risk due to redo sternotomy or thoracotomy, endovascular treatment might be an alternative due to its less invasive approach. Consequently, thoracic endovascular aortic repair comprises a therapeutic alternative in individual situations even in Marfan patients, when the landing zones are safe and appropriate. In cases of failed endovascular therapy, however, conversion to open surgery remains still an option with acceptable results, although the distal and proximal clamping positions change inappropriate with larger extensions due to the aortic stent.

Aims: Laparoscopic fundoplication is the standard surgical therapy for managing gastroesophageal reflux disease. According to the pre-existing esophageal motility of the patient, tailoring antireflux surgery has been proposed in order to avoid postoperative dysphagia. Thus, the aim of this study is to evaluate the long-term results following this tailored concept., Methods: One-hundred sixty patients were included in this prospective study. A 360° Nissen fundoplication (NF) was performed on n = 127 patients with a normal esophageal peristalsis, whereas a 270° Toupet fundoplication (TF) was conducted on n = 33 patients having an esophageal motility disorder. Before surgery, all the patients were subjected to pH-metry, manometry, gastroscopy, and they had to respond to a standardized questionnaire. Postoperatively, pH-metry, and manometry were performed. In addition to the questionnaire, side effects and complications were evaluated., Results: The NF cohort and the TF cohort were each followed up for an average of 39 ± 13 months and 43 ± 12 months, respectively. Dysphagia was significantly reduced after NF (p = .033). The TF, however, decreased the intensity but not the incidence of dysphagia (p = .884). Heartburn was significantly diminished in both cohorts. The DeMeester score was significantly reduced after NF, whereas it was not significantly reduced following TF with a still evident, pathological acid reflux occurring postoperatively., Conclusion: Our data indicate that tailoring antireflux surgery to the esophageal motility of the patient seems unnecessary. In summary, technical surgical aspects appear to be more important for clinical outcome.

Purpose: To test the feasibility of carbon dioxide (CO(2))-enhanced computed tomography (CT)-guided placement of infrarenal abdominal aortic stent-grafts in an animal model., Methods: Appearance of a stent-graft mounted on its deployment system and the feasibility of CT fluoroscopy-guided placement were analyzed in an in vitro setting. Five domestic pigs weighing 70 to 80 kg underwent CO(2)-enhanced 64-slice CT arteriography (CTA). After surgical exposure of the right iliac artery, an 18-mm stent-graft was advanced into the abdominal aorta. Infrarenal position of the graft was monitored using CT fluoroscopy with CO(2) administered intermittently in a flow-regulated manner using a computer-controlled injection system. After the final position of the stent-graft was determined, the graft was deployed under CT fluoroscopy guidance. Graft position was confirmed by contrast enhanced 64-slice CTA and conventional catheter angiography. To quantitatively assess the position of the stent-graft, the distance between the proximal stent struts and the radiopaque marker was determined using an electronic caliper., Results: CT-guided placement of infrarenal aortic stent-grafts was feasible in all animals without complications. CO(2)-enhanced CTA allowed for the identification of the renal arteries in all animals. CT fluoroscopy permitted the continuous online monitoring of stent deployment. In all animals, the grafts were placed without impairment of renal artery flow or stent-graft dislocation. The mean distance between the stent-graft and origin of the more caudal renal artery was 0.9+/-0.3 mm., Conclusion: CO(2)-enhanced CT fluoroscopy permits the precise placement of infrarenal aortic stent-grafts in an animal model.

Background: Anastomotic leakage is a relevant surgical complication. The aim of the study was to investigate the influence of a controlled preoperative zinc deficiency on the extracellular matrix composition of colon anastomosis., Materials and Methods: Forty male Wistar rats were randomized to either a zinc deficiency group (n = 20) or a control group (n = 20). In each animal, a transverse colonic end-to-end anastomosis was performed. On postoperative day 7, the surface of the mucosal villi, expression of matrix metalloproteinases (MMP) 2, 8, 9, and 13, and both the number of proliferating cells (Ki67) and apoptotic cells, as well as the collagen types I/III ratio were analyzed. Within the anastomotic area the mesenterial region and the antimesenterial region were analyzed separately., Results: In each group, one anastomotic leakage was detected. Expression of both MMP 2, 9, and 13 was significantly higher, and expression of Ki67 was significantly reduced in the zinc deficient group both mesenterial and antimesenterial. The collagen types I/III ratio was reduced in the zinc deficiency group by trend, without statistical significance neither mesenterial nor antimesenterial. Likewise, zinc deficiency affected neither the expression of MMP 8 nor the rate of apoptotic cells, respectively. Analyses of the surface of the mucosal villi revealed no significant differences comparing the groups with neither mesenterial nor antimesenterial., Conclusions: Our study constitutes the known negative effect of zinc deficiency on wound healing. Zinc deficiency significantly increased the activity of MMPs (2, 9, and 13), caused a reduced collagen type I/III ratio, and delayed cell proliferation and quality of intestinal wound healing.

Central venous access devices are extensively used for long-term chemotherapy and parenteral nutrition. However, there are some possible immediate, early, and late complications related to the implantation technique, care, and maintenance. We present the uncommon occurrence of a thrombosis of the internal jugular vein due to a spontaneous migration of a Port-A-Cath catheter into the ipsilateral internal jugular vein as a delayed complication of a central venous access catheter implanted for chemotherapy delivery. A review of the literature is given, and the factors responsible for this unusual complication will be discussed.

In the early period following surgery, it is very important to reveal any complications. In this article the role of ultrasound in recognizing postoperative complications is demonstrated. Ultrasound findings in typical complications of abdominal surgery such as bleeding, abscess formation, acute cholecystitis, pancreatitis, and postoperative ileus are described. The diagnosis of postoperative bleeding, acute cholecystitis, and ileus is very reliable by ultrasound (sensitivity and specificity >95%). Ultrasonography is inferior to computed tomography in detecting pancreatitis and abscess formation. The guiding of interventions by ultrasound offers additional therapeutic options.

Background/aims: Mortality in mesenteric ischaemia can be reduced by an optimised extent of resection. Up to now, no technique supplementing a surgeon's experience has achieved clinical acceptance. Besides a qualitative interpretation, the new technique of computer-assisted laser-fluorescence videography affords quantification of staining intensities. The aim of this study was to investigate the scientific value of this technique in mesenteric ischaemia in a rabbit model of controlled mesenteric ischaemia and reperfusion., Methods: We used an established rabbit model of mesenteric ischaemia (group I, n=6) and reperfusion (group II, n=6). In each animal, three loops (each of 10 cm) of the small intestine were clamped (group I, 40 min; group II, 60 and 20 min reperfusion). For further evaluation, all loops were divided into five segments of 2 x 2 cm (total number of investigated areas, n=180). Measurement of vascular patency was performed by laser-fluorescence videography (pixel intensity per second). As standard, we used radioactive microspheres (impulse per minute per gram). In addition, the extent of ischaemic tissue damage was identified by histological examination. Statistical data were analysed by using regression analysis to define the regression coefficient r., Results/findings: Laser-fluorescence videography and the microsphere technique demonstrated a close and linear correlation: ischaemic segments, r=0.90+/-0.07; reperfusion segments, r=0.85+/-0.02; overall, r=0.92+/-0.07. There was no reproducible correlation to cellular damage in histology., Interpretation/conclusion: Computer-assisted laser-fluorescence videography is a feasible, reliable, and valid experimental method for the detection of mesenteric blood supply and intestinal microcirculation. Clinical application is conceivable in mesenteric ischaemia and infarction as well as the operative transposition of intestine. As limiting values to identify the irreversible necrosis are not yet defined, further studies have to analyse the clinical impact more precisely.

Isolated edematous swelling of Bauhin's valve is a rare finding in cases of non-specific abdominal complaints in the lower right abdominal quadrant. The differential diagnosis includes entities such as tumours, chronic gastrointestinal inflammation and ileocoecal intussusception as well as specific infections, all of which require individual therapy. Based on two current cases and a review of the literature, aetiology, clinical picture and diagnostic findings of isolated edema of the ileocoecal valve are described. The typical ultrasound findings are presented. Due to its potential of excluding other diseases, modern ultrasound offers promising results in the case of isolated edematous swelling of Bauhin's valve.