A comparison of non-absorbable polymeric clips and staplers for laparoscopic appendiceal stump closure: analysis of 618 adult patients.

PURPOSE: The aim of this long-term study was the comparison of appendiceal stump closure with polymeric clips or staplers with respect to perioperative costs and surgical outcome under routine conditions in a university centre. METHODS: For this retrospective chart review, a total of 618 patients undergoing laparoscopic appendectomy for suspected acute appendicitis between 2010 and 2017 were reviewed: 410 patients in the stapler group and 208 patients in the clip group. The database contained demographic data, operation time, inflammation parameters, closure method of the stump, surgeon status, length of hospital stay, and complications as well as histology reports. The costs were also compared. RESULTS: Clip application was more likely among younger patients (mean age 33.6 years vs. 41.7 years). Histopathological evidence for appendiceal pathology was found in 96.6% of patients in the clip group and 99.5% of patients in the stapler group. Laparoscopic appendectomy in the clip group was more frequently performed by resident physicians (69.2%) than in the stapler group (57.8%). The mean postoperative stay was 2.9 days in the clip group and 3.7 days in the stapler group. The use of the polymeric clip resulted in considerable cost savings (19.94€ vs. 348.70€). CONCLUSIONS: The use of polymeric clips for appendiceal stump closure during appendectomy is safe and effective. The base of the appendix is amenable to clipping in 32% of appendectomies in adult patients. This study supports the use of polymeric clips over staplers to decrease cost and environmental impact.

Randomized study of the influence of two-dimensional versus three-dimensional imaging using a novel 3D head-mounted display (HMS-3000MT) on performance of laparoscopic inguinal hernia repair.

BACKGROUND: 3D laparoscopy has proven to be superior to the 2D approach in experimental settings. The aim of the present study was to investigate the influence of 3D laparoscopy using a novel head-mounted display on the performance of defined steps within a laparoscopic inguinal hernia repair. This effect was investigated both in laparoscopically advanced surgeons and in beginners. METHODS: Patients suffering from symptomatic inguinal hernia were randomly assigned to laparoscopic hernia repair using either a head-mounted 3D display or a conventional 2D laparoscopic approach. Operative performance of both groups was compared in terms of the time taken for mesh placement and for peritoneal suturing. Additionally, quality of imaging and physical discomfort were assessed. RESULTS: The use of a head-mounted 3D display was able to shorten the time required for placement of the mesh as well as that for peritoneal suturing, both for experienced and novice surgeons when compared to the conventional 2D approach. 3D laparoscopy was significantly superior to 2D laparoscopy in terms of depth perception, image sharpness and image contrast. Additionally, increased impairment caused by ghosting effects could not be detected in 3D laparoscopy. Evaluation of image quality was independent of experience in laparoscopic surgery. However, use of a head-mounted 3D display resulted in a significant impairment of surgeon's comfort when compared to 2D laparoscopy. Thereby, the greatest impairment was caused by ear discomfort. CONCLUSIONS: This is the first study examining the effect of a head-mounted 3D system on the performance of laparoscopy in a randomized controlled trial (RCT) showing a clear advantage of this system in surgical performance as well as in depth perception and image quality.

[Principles of Teaching in Surgery - State of the Art]. / Was muss der Chirurg über Aus- und Weiterbildung in der Chirurgie wissen?

Ten to 15 years ago the number of applications for a surgical residency position was very much larger than the positions available. Today, this situation has clearly reversed itself as indicated through a noticeable deficit in recruits. The decision to become a surgeon has become more uncommon. This can be blamed upon not only the demotivatingly viewed "work-life imbalance" associated with being a surgeon, but also on the basically non-inspiring training process during medical school. Due to the fact that university educators/instructors are not fundamentally trained teachers, they often fail in their capacity to convey their extensive knowledge to medical students and potentially future surgical residents. The quality of primary as well as postgraduate training is an important central factor in the effort to once again restore the attractive image of surgery within the realm of the medical disciplines. This paper presents an overview of the basic modern training concepts by which every surgeon should be able to effectively convey knowledge and practical skills. Furthermore, this work should inspire a more intensive interest in clinical graduate and postgraduate education. Due to the hand in hand relationship, this manuscript does not differentiate between student teaching and postgraduate training.

Incisional hernia repair following pancreatic surgery-open vs laparoscopic approach.

INTRODUCTION: For pancreatic procedures, transverse and midline or combined approaches are used. Having an increased morbidity after pancreatic surgery, these patients have an increased risk of developing an incisional hernia. In the following, we will analyze how the results of incisional hernia surgery after pancreatic surgery are presented in the Herniamed Registry. METHODS: Hospitals and surgeons from Germany, Austria and Switzerland can voluntarily enter all routinely performed hernia operations prospectively into the Herniamed Registry. All patients sign a special informed consent declaration that they agree to the documentation of their treatment in the Herniamed Registry. Perioperative complications (intraoperative complications, postoperative complications, complication-related reoperations and general complications) are recorded up to 30 days after surgery. After 1, 5, and 10 years, patients and primary care physicians are contacted and asked about any pain at rest, pain on exertion, chronic pain requiring treatment or recurrence. This retrospective analysis of prospectively collected data compares the outcomes of minimally invasive vs open techniques in incisional hernia repair after pancreatic surgery. RESULTS: Relative to the total number of all incisional hernia patients in the Herniamed Registry, the proportion after pancreatic surgery with 1-year follow-up was 0.64% (n = 461) patients. 95% of previous pancreatic surgeries were open. Minimally invasive incisional hernia repair was performed in 17.1% and open repair in 82.9% of cases. 23.2% of the defects were larger than 10 cm and 32.8% were located laterally or were a combination of lateral and medial defects. Among the few differences between the collectives, a significantly higher rate of defect closure (58.1% vs 25.3%; p < 0.001) and drainage (72.8% vs 13.9%; p < 0.001) was found in the open repairs, and larger meshes were seen in the minimally invasive procedures (340.6 cm2 vs 259.6 cm2; p < 0.001). No difference deemed a risk factor for chronic postoperative pain was seen in the rate of preoperative pain between the open and minimally invasive procedures (Appendix Table 4) No significant differences were found in either the perioperative complications or at 1-year follow-up. CONCLUSIONS: Incisional hernias after complex pancreatic surgery can be repaired safely and with a low recurrence rate in both open and minimally invasive techniques.

[Disease-adapted closure of the appendicular stump in laparoscopic appendectomy]. / Stadiengerechte Versorgung der Appendixbasis im Rahmen der laparoskopischen Appendektomie.

The frequency of laparoscopic appendectomy has dramatically increased with it now being the standard procedure for acute appendicitis in many hospitals in Germany. Hence, these hospitals require the personnel, the technique as well as the expertise to guarantee a top standard and quality of appendectomies at all times. Only this will meet the requirements of the high case load and the socio-economical importance of appendectomies. The closure of the appendicular stump is a critical step of this procedure. The three most commonly used techniques consist of the endo-loop, the clip and the endo-stapler. The endo-stapler has the advantage of offering closure and transection of the appendix in one step; it can be employed in all cases of appendicular inflammation; and it allows a partial caecal resection. However, it is quite expensive. The clip and the endo-loop offer the same cost-effectiveness, yet the clip appears to be simpler in use compared to the loop. Also, sharing this feature with the stapler, it offers the possibility of closing and transecting the appendix before dissecting the mesoappendix. A disadvantage of the clip not being shared with the loop is the limitation of clips to appendicular diameters of only up to 16 mm. In summary, we propose a cost-effective disease-adapted closure of the appendicular stump employing the clip in standard appendectomies, with the endo-loop being a good alternative. If clip or loop cannot be applied the stapler is the technique of choice. In particular, it should be used if the base of the appendix is inflamed. Adopting this pathway helps to control the still somewhat higher costs of laparoscopic appendectomies compared to classical open appendectomies.

Quantitative immunohistochemical examination of the local cellular reactions following implantation of biomaterials.

Examining the biocompatibility of implant materials includes the in vivo investigation of the local tissue response following implantation in experimental animals. By contrast to qualitative and semi-quantitative approaches often used in this field, a quantitative technique would facilitate a more accurate determination and better comparability of different studies. Therefore, this study aimed at evaluating the applicability of the free image analysis software ImageJ for fast, easy and reproducible quantification of the tissue response following implantation of titanium samples in rats with subsequent immunohistochemical examination of peri-implant tissue samples for monocytes and macrophages (ED1) and MHC class II positive antigen presenting cells (OX6). The quantification of positively stained cells in the vicinity of the implant pockets was based on a grid-supported manual count carried out using two ImageJ plugins (CellCounter, Grid) and resulted in a mean coefficient of variation of 13.8% (ED1) and 19.6% (OX6) between different investigators and 10.0% (ED1) and 13.8% (OX6) for repeated counting by the same investigator. In conclusion, ImageJ was found to be suitable for morphometric evaluation of the tissue response following implantation, particularly the analysis of discrete cellular events at the tissue-biomaterial interface. The procedure which was used is described in detail, and its advantages and disadvantages are discussed.

Laser-supported diaphanoscopy: a new technique in laparoscopic-endoscopic rendezvous procedures allowing better and more tissue-sparing tumor resection than wedge resection.

BACKGROUND: Locating gastrointestinal stromal tumors (GIST) during laparoscopic surgery continues sometimes to be difficult and inaccurate. In addition, the methods used for tumor mapping often do not lead to precise location of tumors. Also, they are too expensive or too complex for an easy surgical approach. Furthermore, the standard wedge resection often sacrifices too much healthy tissue. METHODS: The current study introduces an innovative tissue-sparing method using laser-supported diaphanoscopy (Endolight) for exact location of GIST during laparoscopic surgery. The instrument was developed by the authors' group. This study retrospectively evaluated two groups of patients experiencing GIST. The first group of 10 patients was treated by standard wedge resection. The second group of 10 patients was treated by Endolight-guided laparoscopic resection during a laparoscopic-endoscopic rendezvous procedure. RESULTS: After precise location of GIST using Endolight, all patients could be successfully resected. The largest resection margins using Endolight (9.8±3.8 mm) were significantly smaller than the largest resection margins using wedge resection (stapler) without Endolight (21.5±9.1 mm; p<0.0001). The average surgery time for the group treated by standard wedge resection was 65 min (range, 28-108 min). The surgery time required for the group treated by Endolight-guided resections ranged from 48 to 189 min (average, 123 min). The number of marks used for Endolight resections ranged from four to seven depending on the location and size of the tumor. CONCLUSION: The reported technique allows the precise location of GIST, leading to exact and tissue-sparing transmural laparoscopic resection of these tumors compared with standard wedge-resection. Laser-supported diaphanoscopy using the newly developed innovative device offers new perspectives and a highly effective technique for resecting GIST that combines an endoscopic with a laparoscopic approach.

Comparison of a 3D head-mounted display (HMS-3000MT) and 3D passive polarizing display with 2D technique for first laparoscopic inguinal hernia repair by novice surgeons.

BACKGROUND: Three-dimensional (3D) laparoscopy improves the surgical skills of novice surgeons and positively affects the learning curve in experimental settings. This study aimed to investigate the effect of a 3D passive polarizing display (3DPPD) and a novel 3D head-mounted display (3DHMD; HMS-3000MT) on the performance of the first laparoscopic inguinal hernia repair by novices and compare both systems with standard high-definition 2D (HD2D) laparoscopy. METHODS: Patients with symptomatic inguinal hernia underwent transabdominal preperitoneal (TAPP) approach hernia repair using 3DHMD, 3DPPD, or a conventional HD2D laparoscopic system. All surgeries were performed for the first time by three laparoscopically novice surgeons. Operative performance was compared in terms of the time taken for mesh placement and peritoneal suturing under standardized conditions. Additionally, visual perception parameters and adverse effects were assessed. RESULTS: The use of both 3D techniques shortened the time required for mesh placement and peritoneal suturing compared with the conventional HD2D approach. Generally, 3D laparoscopy was superior to HD2D laparoscopy in terms of visual perception parameters such as depth perception, sharpness, ghosting, and contrast. However, compared with the use of HD2D laparoscopy, the use of 3DHMD significantly impaired a surgeon's comfort, with the greatest impairment caused by ear discomfort, headaches, and facial and physical discomforts. CONCLUSIONS: The 3DHMD and 3DPPD systems showed clear improvement in first hernia repair laparoscopy by novice surgeons in terms of surgical performance, as well as visual perception; however, the 3DHMD system was not superior to the 3DPPD system. The reduction in training time for new surgeons is obviously advantageous. In this respect, the 3D equipment may be a worthwhile investment.

Laser-supported diaphanoscopy: an innovative technique for locating gastric stromal tumors in gastroscopic-laparoscopic rendezvous: a case series.

Development of an innovative method of endoscopic laser-supported diaphanoscopy, for precise demonstration of the location of gastrointestinal stromal tumors (GISTs) at laparoscopy is described. The equipment consists of a light transmission cable with an anchoring system for the gastric mucosa, a connecting system for the light source, and the laser light source itself. During surgery, transillumination by laser is used to show the shape of the tumor. The resection margins are then marked by electric coagulation. Ten patients have been successfully treated using this technique in laparoscopic-endoscopic rendezvous procedures. Average time of surgery was 123 minutes. The time for marking the shape of the tumor averaged 16 minutes. Depending on tumor location and size, 4-7 marks were used, and resection margins were 4-15 mm. This new and effective technique facilitates precise locating of gastric GISTs leading to exact and tissue-sparing transmural laparoscopic resections.

The value of endoscopic diagnosis and the treatment of pancreas injuries following blunt abdominal trauma.

BACKGROUND: Injuries to the pancreas following blunt abdominal trauma are rare due to its protected retroperitoneal position. Many pancreatic lesions remain unnoticed at first and only become apparent when complications arise or during treatment of other injuries. The mortality rate is between 12 and 30%, and if treatment is delayed it is as high as 60%. METHODS: Using medical records over the past 5 years, we investigated when and in what circumstances endoscopic retrograde cholangiopancreaticography (ERCP) was used in the diagnosis and treatment of pancreas injuries after blunt abdominal trauma. Penetrating injuries were not taken into consideration. RESULTS: An ERCP was performed on a total of five patients with suspected injuries to the pancreas after blunt abdominal trauma. No duct participation could be determined in three of the patients with a first degree pancreatic lesion. A 44-year-old woman sustained severe internal and external injuries after a traffic accident. Because of the nature of her injuries, pancreatic left resection with splenectomy was necessary. After the operation, a pancreatic fistula diagnosed. The ductus pancreaticus (DP) was successfully treated by stenting with the use of endoscopic retrograde pancreaticography. A 24-year old woman was kicked in the epigastrium by a horse. On the day after the incident, she complained of increasing pain in the upper abdomen, and she had elevated amylase and lipase levels. Computed tomography scan showed free fluid. Less than 48 h after the accident, ERCP was performed and a leakage in the DP in the head-body region (fourth degree) was identified. We placed a stent, and during the subsequent laparoscopy the omental bursa was flushed out and a drainage laid. After 14 days, the patient was sent home. We removed the drainage 4 weeks after the accident, and the stent after 12 weeks. CONCLUSION: The major advantage of the prompt retrograde discription of the pancreatobiliary system after an accident in which pancreas involvement is suspected is the more precise assessment of the extent of the injuries. If a stent is placed in the same session, it is possible to carry out definitive and interventional treatment.

[Modern treatment of an appendiceal mass]. / Moderne Therapie perityphlitischer Abszesse.

BACKGROUND: The recommendations for the treatment of an appendiceal mass are still controversial. The need for staged appendectomy is still under discussion. PATIENTS AND METHODS: In a retrospective study all patients with the diagnosis appendiceal mass (ICD 10 K35.32) treated in the surgical clinic of the University Clinic in Greifswald between June 1999 and June 2011 were analyzed. RESULTS: A total of 38 patients were included in the study whereby 17 patients (9 male and 8 female) were treated with drainage and antibiotics (group A) and 21 (14 male and 7 female) were treated by immediate surgery (group B). Nonsurgical therapy with drainage of the abscess was found to be efficient. Immediate surgical treatment was also effective and should be performed when signs of peritonitis exist. Interval appendectomy is not indicated.

Absolute protein quantification of clinically relevant cytochrome P450 enzymes and UDP-glucuronosyltransferases by mass spectrometry-based targeted proteomics.

Cytochrome P450 (CYP) enzymes and UDP-glucuronosyltransferases (UGT) are major determinants in the pharmacokinetics of most drugs on the market. To investigate their impact on intestinal and hepatic drug metabolism, we developed and validated quantification methods for nine CYP (CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP2E1, CYP3A4 and CYP3A5) and four UGT enzymes (UGT1A1, UGT1A3, UGT2B7 and UGT2B15) that have been shown to be of clinical relevance in human drug metabolism. Protein quantification was performed by targeted proteomics using liquid chromatography with tandem mass spectrometry (LC-MS/MS)-based determination of enzyme specific peptides after tryptic digestion using in each case stable isotope labelled peptides as internal standard. The chromatography of the respective peptides was performed with gradient elution using a reversed phase (C18) column (Ascentis(®) Express Peptide ES-C18, 100mm×2.1mm, 2.7µm) and 0.1% formic acid (FA) as well as acetonitrile with 0.1% FA as mobile phases at a flow rate of 300µl/min. The MS/MS detection of all peptides was done simultaneously with a scheduled multiple reaction monitoring (MRM) method in the positive mode by monitoring in each case three mass transitions per proteospecific peptide and the internal standard. The assays were validated according to current bioanalytical guidelines with respect to specificity, linearity (0.25-50nM), within-day and between-day accuracy and precision, digestion efficiency as well as stability. Finally, the developed method was successfully applied to determine the CYP and UGT protein amount in human liver and intestinal microsomes. The method was shown to possess sufficient specificity, sensitivity, accuracy, precision and stability to quantify clinically relevant human CYP and UGT enzymes.

[Therapy of pancreatic pseudocysts: endoscopy versus surgery]. / Therapie von Pankreaspseudozysten : Endoskopie vs. Chirurgie.

Pancreatic pseudocysts are frequent complications following acute and chronic pancreatitis as well as abdominal trauma. They originate from enzymatic and/or necrotizing processes within the organ involving the surrounding tissues through inflammatory processes following pancreatic ductal lesion(s). Pseudocysts require definitive treatment if they become symptomatic, progressive, larger than 5 cm after a period of more than 6 weeks and/or have complications. Cystic neoplasms must be excluded before treatment. Endoscopic interventions are commonly accepted first line approaches. Should these fail or not be feasible surgical procedures have been well established and show comparable results. In summary, pancreatic pseudocysts require a reliable diagnostic approach with a multidisciplinary professional management involving gastroenterologists and surgeons.

In vivo investigation of the inflammatory response against allylamine plasma polymer coated titanium implants in a rat model.

Titanium (Ti) is an established biomaterial for bone replacement. However, facilitation of osteoblast attachment by surface modification with chemical groups could improve the implant performance. Therefore, this study aimed to evaluate the effect of a plasma polymerized allylamine (PPAAm) layer on the local inflammation in a rat model. Three series (RM76AB, RM78AB, RM77AB) of PPAAm-treated Ti plates were prepared using different plasma conditions. Twelve male LEW.1A rats received one plate of each series and one uncoated control plate implanted into the back musculature. After 7, 14 and 56 days, four rats were euthanized to remove the implants with surrounding tissue. Total monocytes/macrophages, tissue macrophages, T-cells and MHC-class-II-positive cells were morphometrically counted. On day 14, the macrophage/monocyte number was significantly higher for the controls than for the PPAAm samples. On day 56, the RM76AB and RM78AB samples had significantly lower numbers than RM77AB and the controls. The same was found for the tissue macrophages. No change over time and no differences between the implants were found for the T-cells. For the number of MHC-class-II-positive cells, a significant decrease was found only for the RM78AB implants between day 14 and day 56. Physico-chemical analysis of the PPAAm implants revealed that the RM77AB implants had the lowest water absorption, the highest nitrogen loss and the lowest oxygen uptake after sonication. These results demonstrate that the PPAAm samples and the controls were comparable regarding local inflammation, and that different plasma conditions lead to variations in the material properties which influence the tissue reaction.

[Gastric schwannoma: a "typical" clinical course?]. / Abdominelles Schwannom : Ein "klassischer" Fallbericht?

Intra-abdominal schwannoma is a rare tumor entity. Although often detected incidentally, its diagnosis and surgical planning are difficult-as with all intramural intra-abdominal tumors. Puncturing is often not satisfying due to the inhomogeneous proliferation rates of different regions of the tumor. We describe the procedure using the example of a gastric schwannoma that was found incidentally. The leading symptom was perforation of a peptic stomach ulcer.