Thoracic manifestations of tularaemia: a case series.

BACKGROUND: Tularaemia is a zoonotic disease caused by Francisella tularensis, a highly virulent bacterium that affects humans and small wild animals. It is transmitted through direct contact with infected animals or indirectly through contaminated soil, water or arthropod bites (e.g. ticks). Primary thoracic manifestations of tularaemia are infrequent and, therefore, a diagnostic challenge for clinicians. METHODS: We report six tularaemia cases with exclusively thoracic involvement diagnosed in a clinic for pulmonary diseases in Bavaria between 10/2020 and 02/2022. RESULTS: All patients lived or were active in rural areas, four reported a recent tick bite. All patients presented with thoracic lymphadenopathy and pulmonary tumours or consolidations; all underwent bronchoscopy with EBUS-TBNA of lymph nodes, three lung biopsies as well. Five patients showed inflammatory changes in the endobronchial mucosa. The main histological findings were necrotic epithelioid granulomas with remarkable granulocyte infiltration. All cases were identified by positive serology, five by PCR (here identification of F.t. ssp. Holarctica) from biopsy as well. As first-line therapy, oral ciprofloxacin was given (5/6); in 2/6 cases, a combination of quinolone-rifampicin was given. CONCLUSIONS: Pulmonary tularaemia may occur after tick bites and without extrathoracic manifestations. In patients who present with thoracic lymphadenopathy and pulmonary consolidations and who are exposed to increased outdoor activities, tularaemia should be included in the diagnostic pathway. Histologically, the presence of neutrophil-granulocyte infiltrations might help to distinguish tularaemia from other granulomatous infections, e.g. tuberculosis. The combination of quinolone-rifampicin rather than i.v. gentamicin reduced length of hospital stay in two patients.

The VACStent trial: combined treatment of esophageal leaks by covered stent and endoscopic vacuum therapy.

BACKGROUND: Endoscopic treatment of esophageal leaks, mostly by covered stents or endoscopic vacuum therapy (EVT), has largely improved the clinical outcome in the last decade. However, both techniques suffer from significant limitations. Covered stents are hampered by a high rate of migration and missing functional drainage, whereas endoluminal EVT devices are limited by obstruction of the GI tract. The new design of the VACStent makes it a fully covered stent within a polyurethane sponge cylinder, allowing EVT while stent passage is still open. Initial clinical applications have demonstrated the fundamental concept of the VACStent. METHOD: A prospective multicenter open-label study was performed with the primary endpoint safe practicality, complete leak coverage, and effective suction-treatment of esophageal leaks. Secondary endpoints were prevention of septic conditions, successful leak healing, and complications, in particular stent-migration, local erosions and bleeding. RESULTS: Fifteen patients with different, mostly postoperative anastomotic leaks were enrolled in three centers. A total of 41 VACStents were implanted. The mean number of VACStents per patient was 2.7, with a mean duration of VACStent treatment of 15 days. The primary endpoint was met in all VACStent applications (41/41 implants), resulting in a leak healing rate of 80% (12/15 patients). Septic episodes were prevented in 93% (14/15 patients) and there was no mortality. There were no severe device-related adverse events (SADE) nor significant local bleeding or erosion. Minor stent-dislocation and migration, respectively, was observed in 7%. Oral intake of liquids or food was documented in 87% (13/15 patients). One anastomotic stenosis was seen during follow-up. CONCLUSIONS: VACStent treatment is a safe and effective treatment in esophageal leaks which can be covered by the sponge cylinder. Its application was described as easy and resembling that of conventional GI stents, with an impressive clinical success rate comparable to EVT outcomes. The VACStent offers a new option for clinical treatment of critical situations in esophageal perforations and anastomotic sutureline failures.

Training or non-surgical factors-what determines a good surgical performance? A randomised controlled trial.

BACKGROUND: Acquiring laparoscopic skills is a necessity for every young surgeon. Whether it is a talent or a non-surgical skill that determines the surgical performance of an endoscopic operation has been discussed for years. In other disciplines aptitude testing has become the norm. Airlines, for example, have implemented assessments to test the natural aptitude of future pilots to predict their performance later on. In the medical field, especially surgery, there are no similar comparable tests implemented or even available. This study investigates the influence of potential factors that may predict the successful performance of a complex laparoscopic operation, such as the surgeon's age, gender or learning method. METHODS: This study focussed 70 surgical trainees. It was designed as a secondary analysis of data derived from a 2 × 2 factorial randomised controlled trial of practical training and/or multimedia training (four groups) in an experimental exercise. Both before and then after the training sessions, the participating trainees performed a laparoscopic cholecystectomy in a pelvitrainer. Surgical performance was then evaluated using a modified objective structured assessment of technical skills (OSATS). Participants were classified as 'Skilled' (high score in the pre-test), 'Good Learner' (increase from pre- to post-test) or 'Others' based on the OSATS results. Based on the results of the recorded performance, the training methods as well as non-surgical skills were eventually evaluated in a univariate and in a multivariate analysis. RESULTS: In the pre-training performance 11 candidates were categorised as 'Skilled' (15.7%), 35 participants as 'Good Learners' (50.0%) and 24 participants were classified as 'Others'. The univariate analysis showed that the age, a residency in visceral surgery, and participation in a multimedia training were significantly associated with this grouping. Multivariate analyses revealed that residency in visceral surgery was the most predictive factor for the 'Skilled' participants (p = 0.059), and multimedia training was most predictive for the 'Good Learner' (p = 0.006). Participants in the group of 'Others' who were neither 'Skilled' nor improved in the training phase were younger (p = 0.011) and did not receive multimedia (p < 0.001) or practical (p = 0.025) training. CONCLUSION: The type of learning method has been shown to be the most effective factor to improve laparoscopic skills, with multimedia training proving to be more effective than practical training.

[Diffuse pulmonary meningotheliomatosis]. / Diffuse pulmonale Meningotheliomatose.

In two patients with bilateral micronodular pulmonary changes a diffuse pulmonary meningotheliomatosis was found. A 73-year-old woman presented with bilateral disseminated miliary pulmonary nodules as a radiological incidental finding. The surgical lung biopsy showed multiple tiny nodular proliferations meningothelial-like cells, corresponding "minute pulmonary meningothelial-like nodules", MPMN. A 60-year-old lady with similar radiological findings showed also proliferations of meningothelial-like cells in a transbronchial cryo-biopsy. These lesions are well known to pathologists as curious isolated incidental findings on histological examination of lung specimens. The here described diffuse form of these changes is very rare; its knowledge is important for the differential diagnosis with neoplastic proliferations and other diffuse parenchymal diseases of the lung. This rare diagnosis is made on histological grounds and is also possible in transbronchial biopsies when careful correlation with clinical and radiological data, knowledge of the entity and adequate specimens are provided.

Self-assembled quantum dots in a nanowire system for quantum photonics.

Quantum dots embedded within nanowires represent one of the most promising technologies for applications in quantum photonics. Whereas the top-down fabrication of such structures remains a technological challenge, their bottom-up fabrication through self-assembly is a potentially more powerful strategy. However, present approaches often yield quantum dots with large optical linewidths, making reproducibility of their physical properties difficult. We present a versatile quantum-dot-in-nanowire system that reproducibly self-assembles in core-shell GaAs/AlGaAs nanowires. The quantum dots form at the apex of a GaAs/AlGaAs interface, are highly stable, and can be positioned with nanometre precision relative to the nanowire centre. Unusually, their emission is blue-shifted relative to the lowest energy continuum states of the GaAs core. Large-scale electronic structure calculations show that the origin of the optical transitions lies in quantum confinement due to Al-rich barriers. By emitting in the red and self-assembling on silicon substrates, these quantum dots could therefore become building blocks for solid-state lighting devices and third-generation solar cells.

III-V nanowire arrays: growth and light interaction.

Semiconductor nanowire arrays are reproducible and rational platforms for the realization of high performing designs of light emitting diodes and photovoltaic devices. In this paper we present an overview of the growth challenges of III-V nanowire arrays obtained by molecular beam epitaxy and the design of III-V nanowire arrays on silicon for solar cells. While InAs tends to grow in a relatively straightforward manner on patterned (111)Si substrates, GaAs nanowires remain more challenging; success depends on the cleaning steps, annealing procedure, pattern design and mask thickness. Nanowire arrays might also be used for next generation solar cells. We discuss the photonic effects derived from the vertical configuration of nanowires standing on a substrate and how these are beneficial for photovoltaics. Finally, due to the special interaction of light with standing nanowires we also show that the Raman scattering properties of standing nanowires are modified. This result is important for fundamental studies on the structural and functional properties of nanowires.

Enhancement of second harmonic signal in nanofabricated cones.

Geometrical effects in optical nanostructures on nanoscale can lead to interesting phenomena such as inhibition of spontaneous emission,1,2 high-reflecting omnidirectional mirrors, structures that exhibit low-loss-waveguiding,3 and light confinement.4,5 Here, we demonstrate a similar concept of exploiting the geometrical effects on nanoscale through precisely fabricating lithium niobate (LiNbO3) nanocones arrays devices. We show a strong second harmonic generation (SHG) enhancement, shape and arrangement dependent, up to 4 times bigger than the bulk one. These devices allow below diffraction limited observation, being perfect platforms for single molecule fluorescence microscopy6 or single cell endoscopy.7 Nanocones create a confined illumination volume, devoid from blinking and bleaching, which can excite molecules in nanocones proximity. Illumination volume can be increased by combining the SH enhancement effect with plasmon resonances, excited thanks to a gold plasmonic shell deposited around the nanostructures. This results in a local further enhancement of the SH signal up to 20 times. The global SH enhancement can be rationally designed and tuned through the means of simulations.

Growth mechanisms and process window for InAs V-shaped nanoscale membranes on Si[001].

Organized growth of high aspect-ratio nanostructures such as membranes is interesting for opto-electronic and energy harvesting applications. Recently, we reported a new form of InAs nano-membranes grown on Si substrates with enhanced light scattering properties. In this paper we study how to tune the morphology of the membranes by changing the growth conditions. We examine the role of the V/III ratio, substrate temperature, mask opening size and inter-hole distances in determining the size and shape of the structures. Our results show that the nano-membranes form by a combination of the growth mechanisms of nanowires and the Stranski-Krastanov type of quantum dots: in analogy with nanowires, the length of the membranes strongly depends on the growth temperature and the V/III ratio; the inter-hole distance of the sample determines two different growth regimes: competitive growth for small distances and an independent regime for larger distances. Conversely, and similarly to quantum dots, the width of the nano-membranes increases with the growth temperature and does not exhibit dependence on the V/III ratio. These results constitute an important step towards achieving rational design of high aspect-ratio nanostructures.

Is the transnasal access for esophagogastroduodenoscopy in routine use equal to the transoral route? A prospective, randomized trial.

BACKGROUND AND STUDY AIMS: Routine esophagogastroduodenoscopy (EGD) is increasingly performed without sedation. Transoral (TO) and transnasal (TN) EGD offer different patient comfort and complications. PATIENTS AND METHODS: For a controlled, randomized, clinical trial comparing TN-EGD with TO-EGD without sedation, patients were assigned to TN-EGD using a thin endoscope (group 1, 93 patients), or TO-EGD using a standard endoscope (group 2, 90 patients). Physician-rated procedural time and complications as well as patient-rated side effects and preferences were compared. In group 3, patients (118) who had previously undergone TO-EGD, now underwent TN-EGD. RESULTS: Between group 1 and 2 there was no significant difference for procedural time. Nausea (p = 0.047) and epistaxis (p < 0.001) were significantly more frequent for TN-EGD. Conversion rate from TN- to TO-EGD was low with 4.3 %. For TN-EGD, patients' tolerance was better (p < 0.001), gagging was less (p < 0.001). In case of a future EGD, patients who know both procedures (group 3), strongly vote for TN-EGD (80 %). All groups vote against sedation for future procedures (90 %/90 %/89 %). CONCLUSIONS: Epistaxis can be relevant after TN-EGD, but can mostly be managed conservatively. TN-EGD is superior to TO-EGD regarding subjective and objective gagging as well as procedural tolerance. Patients who experienced both access routes, prefer TN-EGD. TN-EGD without sedation should be aspired for patient comfort and is recommended for routine use.

Clinical implantation of 92 VACStents in the upper gastrointestinal tract of 50 patients-applicability and safety analysis of an innovative endoscopic concept.

Introduction: Endoscopic vacuum therapy (EVT) has emerged as a promising treatment option for upper gastrointestinal wall defects, offering benefits such as evacuation of secretions and removal of wound debris by suction, and reduction and healing of wound cavities to improve clinical outcomes. In contrast, covered stents have a high rate of migration and lack functional drainage, while endoluminal EVT devices obstruct the GI tract. The VACStent is a novel device that combines the benefits of EVT and stent placement. Its design features a fully covered Nitinol-stent within a polyurethane sponge cylinder, enabling EVT while maintaining stent patency. Methods: This study analyzes the pooled data from three different prospective study cohorts to assess the safe practicality of VACStent placement, complete leak coverage, and effective suction-treatment of esophageal leaks. By pooling the data, the study aims to provide a broader base for analysis. Results: In total, trans-nasal derivation of the catheter, suction and drainage of secretion via vacuum pump were performed without any adversity. In the pooled study cohort of 92 VACStent applications, the mean stent indwelling time was 5.2 days (range 2-8 days) without any dislocation of the device. Removal of the VACStent was done without complication, in one case the sponge was lost but subsequently fully preserved. Minor local erosions and bleeding and one subsequent hemostasis were recorded unfrequently during withdrawal of the device (5.4%, 5/92) but no perforation or pressure ulcer. Despite a high heterogeneity regarding primary disease and pretreatments a cure rate of 76% (38/50 patients) could be achieved. Discussion: In summary, insertion and release procedure was regarded as easy and simple with a low potential of dislocation. The VACStent was well tolerated by the patient while keeping the drainage function of the sponge achieving directly a wound closure by continuous suction and improving the healing process. The implantation of the VACStent provides a promising new procedure for improved clinical treatment in various indications of the upper gastrointestinal wall, which should be validated in larger clinical studies.Clinical Trial Registration: Identifier [DRKS00016048 and NCT04884334].

Deterioration in quality of life (QoL) in patients with malignant ascites: results from a phase II/III study comparing paracentesis plus catumaxomab with paracentesis alone.

BACKGROUND: Malignant ascites (MA) is associated with poor prognosis and limited palliative therapeutic options. Therefore, quality of life (QoL) assessment is of particular importance to demonstrate new treatment value. Following the demonstration of the superiority of catumaxomab and paracentesis over paracentesis on puncture-free survival, this analysis aimed at comparing deterioration in QoL between both the treatment options. PATIENTS AND METHODS: In a randomised, multicentre, phase II/III study of patients with MA due to epithelial cell adhesion molecule (EpCAM) positive cancer, the QoL was evaluated using the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 items (EORTC QLQ-C30) questionnaire at screening, 1, 3 and 7 months after treatment and in the case of re-puncture on the day of paracentesis. Time to first deterioration in QoL was defined as a decrease in the QoL score of at least five points and compared between the catumaxomab (n=160) and control (n=85) groups using the log-rank test and Cox proportional hazards models adjusted for baseline score, country and primary tumour type. RESULTS: Deterioration in QoL scores appeared more rapidly in the control than in the catumaxomab group (median 19-26 days versus 47-49 days). The difference in time to deterioration in QoL between the groups was statistically significant for all scores (P<0.01). The hazard ratios ranged from 0.08 to 0.24 (P<0.01). CONCLUSIONS: Treatment with catumaxomab delayed deterioration in QoL in patients with MA. Compared with paracentesis alone, catumaxomab enabled patients to benefit from better QoL for a prolonged survival period.

Individual development and uPA-receptor expression of disseminated tumour cells in bone marrow: a reference to early systemic disease in solid cancer.

It is unclear whether disseminated tumour cells detected in bone marrow in early stages of solid cancers indicate a subclinical systemic disease component determining the patient's fate or simply represent mainly irrelevant shed cells. Moreover, characteristics differentiating high and low metastatic potential of disseminated tumour cells are not defined. We performed repeated serial bone marrow biopsies during follow-up in operated gastric cancer patients. Most patients with later tumour relapse revealed either an increase or a constantly high number of tumour cells. In contrast, in patients without recurrence, either clearance of tumour cells or negative or low cell counts were seen. Urokinase plasminogen activator (uPA)-receptor expression on disseminated tumour cells was significantly correlated with increasing tumour cell counts and clinical prognosis. These results demonstrate a systemic component in early solid cancer, indicated by early systemically disseminated tumour cells, which may predict individual disease development.

Laparoscopic extraperitoneal rectal cancer surgery: the clinical practice guidelines of the European Association for Endoscopic Surgery (EAES).

BACKGROUND: The laparoscopic approach is increasingly applied in colorectal surgery. Although laparoscopic surgery in colon cancer has been proved to be safe and feasible with equivalent long-term oncological outcome compared to open surgery, safety and long-term oncological outcome of laparoscopic surgery for rectal cancer remain controversial. Laparoscopic rectal cancer surgery might be efficacious, but indications and limitations are not clearly defined. Therefore, the European Association for Endoscopic Surgery (EAES) has developed this clinical practice guideline. METHODS: An international expert panel was invited to appraise the current literature and to develop evidence-based recommendations. The expert panel constituted for a consensus development conference in May 2010. Thereafter, the recommendations were presented at the annual congress of the EAES in Geneva in June 2010 in a plenary session. A second consensus process (Delphi process) of the recommendations with the explanatory text was necessary due to the changes after the consensus conference. RESULTS: Laparoscopic surgery for extraperitoneal (mid- and low-) rectal cancer is feasible and widely accepted. The laparoscopic approach must offer the same quality of surgical specimen as in open surgery. Short-term outcomes such as bowel function, surgical-site infections, pain and hospital stay are slightly improved with the laparoscopic approach. Laparoscopic resection of rectal cancer is not inferior to the open in terms of disease-free survival, overall survival or local recurrence. Laparoscopic pelvic dissection may impair genitourinary and sexual function after rectal resection, like in open surgery. CONCLUSIONS: Laparoscopic surgery for mid- and low-rectal cancer can be recommended under optimal conditions. Still, most level 1 evidence is for colon cancer surgery rather than rectal cancer. Upcoming results from large randomised trials are awaited to strengthen the evidence for improved short-term results and equal long-term results in comparison with the open approach.

Spatially resolved Raman spectroscopy on indium-catalyzed core-shell germanium nanowires: size effects.

The structure of indium-catalyzed germanium nanowires is investigated by atomic force microscopy, scanning confocal Raman spectroscopy and transmission electron microscopy. The nanowires are formed by a crystalline core and an amorphous shell. We find that the diameter of the crystalline core varies along the nanowire, down to few nanometers. Phonon confinement effects are observed in the regions where the crystalline region is the thinnest. The results are consistent with the thermally insulating behavior of the core-shell nanowires.

[Modern didactics in surgical education--between demand and reality]. / Moderne Didaktik in der chirurgischen Weiterbildung--zwischen Anspruch und Wirklichkeit.

Surgical residency contains an inadequate amount of hands-on training in the operating room and time constraints further make this type of education on the floor unlikely. Due to these deficits in residency training, private surgical courses outside of the established residency programmes are in high demand. Therefore, surgical residents must spend their own resources and time in addition to their residency training in order to receive adequate clinical exposure. Didactic approaches like problem-based learning have begun to influence our modern education. These novel education approaches along with visualisation training, video-based presentations, and multimedia-based training can be useful adjuncts to traditional surgical training.

BIOLAP: biological versus synthetic mesh in laparo-endoscopic inguinal hernia repair: study protocol for a randomized, multicenter, self-controlled clinical trial.

BACKGROUND: Inguinal hernia repair is one of the most common surgical operations globally; more than 20 million groin herniae are repaired annually worldwide. Recurrence after an inguinal hernia operation is a considerable clinical problem. Another remaining problem after hernia surgery is the occurrence of chronic pain. Up to now, the use of synthetic meshes is the standard procedure, but there is increasing evidence that biological meshes could be advantageous concerning the occurrence of chronic pain due to different postoperative remodeling, without the disadvantages of a life-long implant. We hypothesize that the use of a biological mesh reduces postoperative pain without being inferior in terms of recurrence rate compared with a synthetic mesh. METHODS/DESIGN: The trial compares possible the advantages of biological matrices to synthetic meshes in laparo-endoscopic inguinal hernia repair. Four hundred and ninety-six patients with primary bilateral inguinal herniae in 20 German hernia centers will be enrolled. Biological mesh is used for one of the bilateral herniae, the other side will be operated on with a synthetic mesh. Randomization will preset which side is repaired with which material and trial participants will not be informed about the location of each mesh type. The primary endpoints will be intensity of postoperative local pain and the incidence of recurrent hernia after 2 years. DISCUSSION: There is no reasonably sized trial that assesses the use of biological meshes in laparo-endoscopic inguinal hernia repair. Our self-controlled trial design allows a direct comparison of the two meshes with very few confounding factors as well as minimizing the exclusion criteria. As we compare CE-certified medical devices in their designated indication the medical risk is not different compared to routine clinical care. Due to the common nature of bilateral inguinal hernia, a high recruitment rate is achievable. Because guidelines for hernia repair have stressed the need for reliable data on the already frequent use of biological meshes, we can expect our trial to have a direct implication on hernia-repair standards. TRIAL REGISTRATION: German Clinical Trials Register, ID: DRKS00010178 . Registered on 16.June.2016. BIOLAP underwent full external peer review as part of the funding process with the German Research Foundation.

Laparoscopic live donor nephrectomy for right kidneys: Experience in a German community hospital.

BACKGROUND: Laparoscopic live donor nephrectomy has become the new gold standard for kidney procurement in many high-volume transplant centres worldwide, but it is often limited to left-sided donor kidneys. Concerns about adequate anatomical renal vessel length and sufficient surgical exposure are the main obstacles to the use of the laparoscopic approach for right kidney live donors as well. MATERIAL AND METHODS: From 1998 to 2006 we performed laparoscopic kidney procurement in 73 live kidney donors on an intention-to-treat basis, harvesting a total of 48 left (LKG) and 25 right kidneys (RKG) for transplantation. We compared these two groups with respect to operating time, conversion rate, complications, hospital stay, and recipient outcome. RESULTS: There were no differences in outcome of donor patients after left (D-LKG) or right laparoscopic donor nephrectomy (D-RKG). Operating time was 160 min in D-RKG versus 164 min in D-LKG. Warm ischemia was below 150 s in both groups. Hospital stay was 7.0 (D-RKG) versus 6.7 days (D-LKG). Negative events on the donor site were one temporary nerve irritation in each group and one postoperative retroperitoneal hematoma in the left kidney group. Reasons to convert to open nephrectomy were bleeding in two patients in the left kidney group and adhesions in one patient in the right kidney group. The outcome of the recipients after left (R-LKG) or right kidney (R-RKG) transplantation was similar. One kidney was lost due to renal vein thrombosis (R-LKG). Postoperative ureter complications occurred in one patient of each group. One patient of the R-RKG and two patients of the R-LKG required lymphocele fenestration. All other kidney transplants worked without problems. CONCLUSION: Laparoscopic donor nephrectomy is a safe procedure and has been established as the method of choice for live kidney donation in our clinic. Laparoscopic procurement of right and left kidneys can be performed with comparable quality and outcome for donors and recipients.

Liver transplantation for hilar cholangiocarcinoma: a German survey.

BACKGROUND: The present study reports a German survey addressing outcomes in nonselected historical series of liver transplantation (OLT) for hilar cholangiocarcinoma (HL). PATIENTS AND METHODS: We sent to all 25 German transplant centers performing OLT a survey that addressed (1) the number of OLTs for HL and the period during which they were performed; (2) the incidence of HL diagnosed prior to OLT/rate of incidental HL (for example, in primary sclerosing cholangitis); (3) tumor stages according to Union Internationale Centre le Cancer; (4) patient survival; and (5) tumor recurrence rate. RESULTS: Eighty percent of centers responded, reporting 47 patients who were transplanted for HL. Tumors were classified as pT2 (25%), pT3 (73%), or pT4 (2%). HL was diagnosed incidentally in 10% of cases. A primary diagnosis of PSC was observed in 16% of patients. Overall median survival was 35.5 months. When in-hospital mortality (n = 12) was excluded, the median survival was 45.4 months, corresponding to 3- and 5-year survival rates of 42% and 31%, versus 31% and 22% when in-hospital mortality was included. HL recurred in 34% of cases. Three- and 5-year survivals for the 15 patients transplanted since 1998 was 57% and 48%, respectively. Median survival ranged from 20 to 42 months based on the time period (P = .014). CONCLUSIONS: The acceptable overall survival, the improved results after careful patient selection since 1998, and the encouraging outcomes from recent studies all suggest that OLT may be a potential treatment for selected cases of HL. Prospective multicenter randomized studies with strict selection criteria and multimodal treatments seem necessary.

What is the evidence for the use of biologic or biosynthetic meshes in abdominal wall reconstruction?

INTRODUCTION: Although many surgeons have adopted the use of biologic and biosynthetic meshes in complex abdominal wall hernia repair, others have questioned the use of these products. Criticism is addressed in several review articles on the poor standard of studies reporting on the use of biologic meshes for different abdominal wall repairs. The aim of this consensus review is to conduct an evidence-based analysis of the efficacy of biologic and biosynthetic meshes in predefined clinical situations. METHODS: A European working group, "BioMesh Study Group", composed of invited surgeons with a special interest in surgical meshes, formulated key questions, and forwarded them for processing in subgroups. In January 2016, a workshop was held in Berlin where the findings were presented, discussed, and voted on for consensus. Findings were set out in writing by the subgroups followed by consensus being reached. For the review, 114 studies and background analyses were used. RESULTS: The cumulative data regarding biologic mesh under contaminated conditions do not support the claim that it is better than synthetic mesh. Biologic mesh use should be avoided when bridging is needed. In inguinal hernia repair biologic and biosynthetic meshes do not have a clear advantage over the synthetic meshes. For prevention of incisional or parastomal hernias, there is no evidence to support the use of biologic/biosynthetic meshes. In complex abdominal wall hernia repairs (incarcerated hernia, parastomal hernia, infected mesh, open abdomen, enterocutaneous fistula, and component separation technique), biologic and biosynthetic meshes do not provide a superior alternative to synthetic meshes. CONCLUSION: The routine use of biologic and biosynthetic meshes cannot be recommended.