A single application of cold atmospheric plasma (CAP) improves blood flow parameters in chronic wounds.

OBJECTIVE: To find out whether application of cold atmospheric plasma (CAP) affects microcirculation in chronic wounds. METHODS: We treated 20 patients with chronic wounds on the lower extremity with CAP. Blood flow parameters of wounds were assessed with combined Laser-Doppler-Flowmetry and spectrophotometry in tissue depth of 2 and 6-8 mm. Parameters were assessed under standardized conditions before and over the course of 30 min after application of CAP. RESULTS: Deep capillary blood flow increased significantly by up to 24.33% (percentage change) after treatment with CAP and remained significantly elevated until the end of measuring period at 30 min. Superficial oxygen tissue saturation was significantly elevated by 14.05% for the first 5 min after treatment. Postcapillary venous filling pressure was significantly elevated by 10.23% 19 min after CAP and stayed significantly elevated starting from minute 24 until the end of measuring. CONCLUSION: Cold atmospheric plasma increases microcirculation parameters in chronic wounds significantly. As CAP is known for its benefits in wound healing, the effects observed may explain the improved healing of chronic wounds after its use. Whether CAP-application can increase blood flow in chronic wounds for longer periods of time or boosts blood flow when applied more than once should be subject to further research.

Radiation-Free Thoracic Endovascular Aneurysm Repair with Fiberoptic and Electromagnetic Guidance: A Phantom Study.

PURPOSE: To evaluate the feasibility and accuracy of a radiation-free implantation of a thoracic aortic stent graft employing fiberoptic and electromagnetic tracking in an anthropomorphic phantom. MATERIALS AND METHODS: An anthropomorphic phantom was manufactured based on computed tomography (CT) angiography data from a patient. An aortic stent graft application system was equipped with a fiber Bragg gratings and 3 electromagnetic sensors. The stent graft was navigated in the phantom by 3 interventionalists using the tracking data generated by both technologies. One implantation procedure was performed. The technical success of the procedure was evaluated using digital subtraction angiography and CT angiography (before and after the intervention). Tracking accuracy was determined at various anatomical landmarks based on separately acquired fluoroscopic images. The mean/maximum errors were measured for the stent graft application system and the tip/end of the stent graft. RESULTS: The procedure resulted in technical success with a mean error below 3 mm for the entire application system and <2 mm for the position of the tip of the stent graft. Navigation/implantation and handling of the device were rated sufficiently accurate and on par with comparable, routinely used stent graft application systems. CONCLUSIONS: The study demonstrates successful stent graft implantation during a thoracic endovascular aortic repair procedure employing advanced guidance techniques and avoiding fluoroscopic imaging. This is an essential step in facilitating the implantation of stent grafts and reducing the health risks associated with ionizing radiation during endovascular procedures.

The repetitive application of cold atmospheric plasma (CAP) improves microcirculation parameters in chronic wounds.

BACKGROUND: Chronic wounds, such as venous leg ulcers, diabetic foot ulcers, and pressure ulcers, impose a significant burden on patients and health care systems worldwide. Cold atmospheric plasma (CAP) accelerates wound healing and decreases bacterial load in chronic wounds in both in vitro and in vivo experiments. For the first time, we examined the effects of a repetitive application of CAP on the microcirculation in chronic wounds. HYPOTHESIS: The repetitive application of cold atmospheric plasma application further improves microcirculation in chronic wounds. METHODS: Twenty patients with chronic wounds were treated repetitively with CAP. The repetitive application consisted of three CAP sessions, each lasting 90 s and separated by a 10-minute microcirculation measuring period. Microcirculation parameters were assessed with combined Laser-Doppler-Flowmetry and spectrophotometry in a tissue depth of 2 mm. RESULTS: Tissue oxygen saturation was significantly increased after the first CAP application. The effect amplitude and duration were further increased after the second and third CAP application with a maximum increase by 16,7% (percent change; p = 0,004 vs. baseline) after the third application. There was no significant increase in capillary blood flow until the third CAP application. After the third CAP application, an increase by 22,6% (p = 0,014) was observed. Postcapillary filling pressure was not significantly increased over the measuring period. The repetitive application of CAP further enhances the microcirculation in chronic wounds compared to a single application. CONCLUSION: The repetitive application of CAP boosts and prolongs tissue oxygen saturation and capillary blood flow in chronic wounds compared to a single application. This insight could provide an impetus for new treatment protocols.

Confocal laser microscopy as novel approach for real-time and in-vivo tissue examination during minimal-invasive surgery in colon cancer.

BACKGROUND: Histological analysis of surgical specimen is the gold standard for cancer classification. In particular, frozen histological diagnosis of vague peritoneal spots or uncertain excision of tumors plays a crucial role in the decision to proceed with or abandon an operation. Confocal laser microscopy (CLM) enables in-vivo and real-time high-resolution tissue analysis. This method has already been used during endoscopic assessments analyzing transformation of esophageal or colon mucosa. We examined whether a CLM device enables to distinguish between non-malignant and malignant tissue in vivo and real time and enables to assign peritoneal carcinomatosis spots to their primary tumor. In addition, we investigated whether the newly developed CLM camera device causes any tissue damage. METHODS: CC531 colon carcinoma cells were implanted on the serosa side of the colon and intraperitoneally in Wag/Rija rats via laparotomy. After 7 days of tumor growth, confocal laser microscopy in vivo was performed by re-laparotomy. Images of non-malignant and malignant tissue were characterized in terms of specific signal pattern. No fluorescent dye was used. Correlations to findings in conventional histology were systematically recorded and described. Potential tissue damage was examined by conventional histology. RESULTS: All animals survived the operative procedure and could be evaluated 7 days following surgery. No unexpected death occurred after surgery. Non-malignant colon is defined by small cycles of the microvilli of the colon. There is repetitive deregulated structure in colon carcinoma. Peritoneal carcinomatosis showed the same structural pattern as in primary colon carcinoma. In all examined cases, it was possible to differentiate between peritoneal carcinomatosis spots and non-malignant peritoneum. The CLM device did not cause any tissue damage. CONCLUSIONS: The CLM camera device reported here is feasible to identify peritoneal carcinomatosis spots, assign these spots to the primary tumor, as well as distinguish between non-malignant and malignant tissue in without using any fluorescent dye.

[Laparoscopic Treatment of Splenic Artery Aneurysm]. / Laparoskopisches Ausschalten eines Aneurysmas der A. lienalis.

OBJECTIVE: Visceral artery aneurysms are a rare but dangerous vascular pathology. The branches of the coeliac trunc are most frequently affected, especially the splenic artery. A visceral aneurysm is usually diagnosed only when a bleeding complication occurs due to rupture. It is therefore recommended to treat this pathology at an early stage after diagnosis. Endovascular elimination is the preferred procedure. However, if endovascular elimination is not suitable, the visceral aneurysm can be successfully treated by minimally invasive surgery. INDICATIONS: Splenic artery aneurysms are located at the splenic hilum, and are therefore considered to be at high risk of splenic ischemia and secondary complications following endovascular coiling. PROCEDURE: Laparoscopic treatment of splenic artery aneurysm. CONCLUSION: In the case of complex vascular pathologies unsuitable for an endovascular approach, laparoscopic treatment of splenic artery aneurysm is a safe and effective minimally invasive option and alternative.

Analysis of laparoscopic laser liver resection in standardized porcine model.

BACKGROUND: Hepatocellular carcinoma is a highly prevalent and lethal primary neoplasia of the liver and metastases of other malignancies affect most frequently the liver. Minimally invasive surgical approach for liver resections is advancing. Dissection of liver parenchyma by laparoscopic technique remains challenging and new technologies are in need. Therefore, we asked whether it is feasible to dissect liver tissue comparably in terms of speed and hemostasis with a non-contact 1.9-µm cw-laser device and whether there are differences in the postoperative healing process compared to a gold standard device (ultrasound aspirator) in an experimental model. METHODS: Laparoscopic laser and ultrasound aspirator standardized partial liver resections were performed in seven pigs. Resection time, hemostasis time, and blood loss were evaluated. After at least 10 days, representative specimen of the resection areas was collected via re-laparoscopy and biopsy and side effects like hematoma, abscess, or bilioma were noted. Histologically, coagulation necrosis margin, granulation tissue zone, tissue fibrosis, and giant cell count were analyzed. RESULTS: Laparoscopic laser liver resection was three times faster compared to the laparoscopic ultrasound aspirator. Blood loss was equal in both groups. No side effects like hematoma or bilioma occurred. Histologically, specimen showed the same expansion of coagulation necrosis zone and granulation tissue. Fibrotic scar could be determined in three cases in both groups, respectively. However, giant cell count was significant higher in the laser resection group. CONCLUSIONS: The 1.9-µm cw-laser device enables a safe and fast liver resection in an experimental pig model compared to a gold standard (ultrasound aspirator) laparoscopic liver resection method. Wound healing is not interfered by laser liver resection.

Laparoscopic Confocal Laser Microscopy Without Fluorescent Injection: A Pilot Ex Vivo Study in Colon Cancer.

Introduction Histological analysis of surgical specimen is the gold standard for cancer classification. In particular, frozen histological diagnosis of vague peritoneal spots or uncertain excision of tumors plays a crucial role for proceeding with or without change of the operation procedure. Confocal laser microscopy (CLM) enables in vivo and real-time high-resolution tissue analysis. To evaluate a novel technique of CLM without any fluorescent dye, this pilot ex vivo study demonstrates a CLM camera device for minimal invasive surgical approach. Methods In 5 cases, a laparoscopic CLM camera was used for examining colon and rectum specimen. Images of nonmalignant and malignant intestinal mucosa were characterized in terms of specific signal-patterns. No fluorescent dye was used. Correlations to findings in conventional histology were systematically recorded and described. Results Using this CLM camera device, it is possible to analyze colon specimen mucosa. Nonmalignant and malignant intestinal mucosa show specific signal patterns. Nonmalignant mucosa is defined by honeycomb structure. There is deregulated structure in colon and rectum carcinoma mucosa. The inside lumen is irregular. The radial border appears swollen with reduced contrast. Discussion This pilot study shows that the assessment of colon mucosa with a prototype of CLM camera for minimally invasive surgical approach without any fluorescent dye is feasible. It is possible to differentiate between benign and malignant mucosa in colon specimen by easy to evaluate and reproducible parameters. These first steps of this pioneering achievement to establish CLM in minimal invasive surgical procedures show a great potential for a more reliable intraoperative evaluation of suspect foci.

Ultrasound-based tumor movement compensation during navigated laparoscopic liver interventions.

BACKGROUND: Image-guided navigation aims to provide better orientation and accuracy in laparoscopic interventions. However, the ability of the navigation system to reflect anatomical changes and maintain high accuracy during the procedure is crucial. This is particularly challenging in soft organs such as the liver, where surgical manipulation causes significant tumor movements. We propose a fast approach to obtain an accurate estimation of the tumor position throughout the procedure. METHODS: Initially, a three-dimensional (3D) ultrasound image is reconstructed and the tumor is segmented. During surgery, the position of the tumor is updated based on newly acquired tracked ultrasound images. The initial segmentation of the tumor is used to automatically detect the tumor and update its position in the navigation system. Two experiments were conducted. First, a controlled phantom motion using a robot was performed to validate the tracking accuracy. Second, a needle navigation scenario based on pseudotumors injected into ex vivo porcine liver was studied. RESULT: In the robot-based evaluation, the approach estimated the target location with an accuracy of 0.4 ± 0.3 mm. The mean navigation error in the needle experiment was 1.2 ± 0.6 mm, and the algorithm compensated for tumor shifts up to 38 mm in an average time of 1 s. CONCLUSION: We demonstrated a navigation approach based on tracked laparoscopic ultrasound (LUS), and focused on the neighborhood of the tumor. Our experimental results indicate that this approach can be used to quickly and accurately compensate for tumor movements caused by surgical manipulation during laparoscopic interventions. The proposed approach has the advantage of being based on the routinely used LUS; however, it upgrades its functionality to estimate the tumor position in 3D. Hence, the approach is repeatable throughout surgery, and enables high navigation accuracy to be maintained.

Aneuploidy and elevated CEA indicate an increased risk for metachronous metastasis in colorectal cancer.

PURPOSE: Presently, no markers exist to predict metachronous metastasis at the time a primary colorectal cancer is diagnosed. While aneuploidy indicates poor survival prognosis and elevated carcinoembryonic antigen (CEA) levels the presence of recurrent disease, the predictive value of both markers regarding imminent metachronous metastases is unclear. METHODS: Sixty patients with distant recurrence throughout a 5-year follow-up (TM+) were randomly chosen and 60 patients without metastasis matched to this cohort (TM-). In addition, an enlarged collective (n = 217; n TM+ = 85, n TM- = 132) with median follow-up of 79.2 months was assessed by logistic regression regarding metachronous metastases. Univariate and stepwise regression analyses included clinicopathological characteristics, preoperative CEA levels and aneuploidy assessed by DNA image cytometry. RESULTS: The matched-pair collective showed aneuploidy in 71.1 % (TM-) and 85.0 % (TM+; p = 0.076), and elevated CEA in 24.5 % (TM-) and 52.2 % [TM+; odds ratio (OR), 3.414; p = 0.007]. The enlarged collective presented aneuploidy in 71.2 % (TM-) and 83.5 % (TM+; OR 2.050, p = 0.038), and elevated CEA in 28.6 % (TM-) and 48.9 % (TM+; OR 2.391, p = 0.020). Elevated CEA and aneuploidy did not show any association (p = 0.919). In contrast, logistic regression analyses demonstrated that besides increased T category (OR 1.745, p = 0.019), both elevated CEA level (OR 2.633, p = 0.015) and aneuploidy (OR 1.929, p = 0.058) were independent predictive markers for metachronous metastasis. CONCLUSIONS: Our data show that aneuploidy and elevated CEA levels besides increased T category could serve for individual risk assessment to predict metachronous metastases. The fact that still aneuploidy missed the significance level by a small margin emphasizes the need for larger validation studies.

Intrahepatic radiofrequency ablation versus electrochemical treatment ex vivo.

BACKGROUND: Radiofrequency ablation (RFA) and electrochemical treatment (ECT) are two methods of local liver tumor ablation. A reproducible perfusion model allowed us to compare these methods when applied in proximity to vascular structures. MATERIAL AND METHODS: In a porcine liver perfusion model, we used RFA (group A) and ECT (group B) to perform ablations under ultrasound guidance within 10 mm of a vessel and examined the induced necrosis macroscopically and histologically. RESULTS: We created 83 lesions (RFA: 59, ECT: 24) in 27 livers. In group A (mean liver weight: 2046 g), perfusion was macroscopically found to limit necrosis in 52.5% of the procedures. Histology demonstrated the destruction of only 30.4% of the vessel walls within the ablation areas. In group B (mean liver weight: 1885 g), we detected reproducible and sharply demarcated ablation areas both macroscopically and histologically. Necrosis was unaffected by nearby vessels. No viable cells were found perivascularly. Histology showed destruction of the vascular endothelium without any discontinuities. We measured pH values of 0.9 (range: 0.6-1.8) at the anode and 12.2 (range: 11.4-12.6) at the cathode. Treatment time was 100 min when a charge of 300 coulombs was delivered. CONCLUSIONS: Electrochemical treatment is a method of ablation that creates reproducible and predictable volumes of necrosis. It produces sharply demarcated areas of complete necrosis also in perivascular sites. ECT, however, requires much longer treatment times than RFA. In our model, the effects of RFA were considerably limited by perfusion, which caused incomplete areas of necrosis in proximity to vessels.

Metachronous metastasis- and survival-analysis show prognostic importance of lymphadenectomy for colon carcinomas.

BACKGROUND: Lymphadenectomy is performed to assess patient prognosis and to prevent metastasizing. Recently, it was questioned whether lymph node metastases were capable of metastasizing and therefore, if lymphadenectomy was still adequate. We evaluated whether the nodal status impacts on the occurrence of distant metastases by analyzing a highly selected cohort of colon cancer patients. METHODS: 1,395 patients underwent surgery exclusively for colon cancer at the University of Lübeck between 01/1993 and 12/2008. The following exclusion criteria were applied: synchronous metastasis, R1-resection, prior/synchronous second carcinoma, age < 50 years, positive family history, inflammatory bowel disease, FAP, HNPCC, and follow-up < 5 years. The remaining 421 patients were divided into groups with (TM+, n = 75) or without (TM-, n = 346) the occurrence of metastasis throughout a 5-year follow-up. RESULTS: Five-year survival rates for TM + and TM- were 21% and 73%, respectively (p < 0.0001). Survival rates differed significantly for N0 vs. N2, grading 2 vs. 3, UICC-I vs. -II and UICC-I vs. -III (p < 0.05). Regression analysis revealed higher age upon diagnosis, increasing N- and increasing T-category to significantly impact on recurrence free survival while increasing N-and T-category were significant parameters for the risk to develop metastases within 5-years after surgery (HR 1.97 and 1.78; p < 0.0001). CONCLUSIONS: Besides a higher T-category, a positive N-stage independently implies a higher probability to develop distant metastases and correlates with poor survival. Our data thus show a prognostic relevance of lymphadenectomy which should therefore be retained until conclusive studies suggest the unimportance of lmyphadenectomy.

Outcome analysis of elderly patients undergoing laparoscopic resection rectopexy for rectal prolapse.

PURPOSE: For treatment of rectal prolapse, abdominal approaches are generally offered to younger patients, whereas perineal, less invasive procedures are considered more beneficial in the elderly. The aim of this study was to analyze whether laparoscopic resection rectopexy (LRR) is suitable for older patients. PATIENTS/METHODS: Patients who received LRR for rectal prolapse were selected from a prospective laparoscopic colorectal surgery database. Perioperative and long-term outcome were compared between patients <75 years old (group A) and ≥75 years old (group B). RESULTS: Of 154 patients, 111 were in group A and 43 in group B. There was one conversion that occurred in group B. Overall mortality rate was 1.3% (n = 2). Both patients were in group B (group B, 4.7%; p = 0.079). Differences in major and minor complications between the groups were not significant. Rates of improvement for incontinence were 62.7% (group A) and 66.7% (group B; p = 0.716); for constipation, the rates were 78.9% (group A) and 73.3% (group B; p = 0.832). All recurrences occurred in group A (n = 10; overall, 10.3%; group A, 13%). After exclusion of patients who had previously received perineal prolapse surgery, recurrence rate was 3.3% overall (group A, 4.3%). CONCLUSIONS: This study supports the benefits of LRR for rectal prolapse in elderly patients. Age per se is not a contraindication for LRR. Elderly patients encounter complications slightly more frequently (although not statistically significant) than younger patients. Therefore, a very careful patient selection in the elderly is of paramount importance. However, the long-term outcome does not seem to differ between younger and elderly patients.

Targeting the MYC interaction network in B-cell lymphoma via histone deacetylase 6 inhibition.

Overexpression of MYC is a genuine cancer driver in lymphomas and related to poor prognosis. However, therapeutic targeting of the transcription factor MYC remains challenging. Here, we show that inhibition of the histone deacetylase 6 (HDAC6) using the HDAC6 inhibitor Marbostat-100 (M-100) reduces oncogenic MYC levels and prevents lymphomagenesis in a mouse model of MYC-induced aggressive B-cell lymphoma. M-100 specifically alters protein-protein interactions by switching the acetylation state of HDAC6 substrates, such as tubulin. Tubulin facilitates nuclear import of MYC, and MYC-dependent B-cell lymphoma cells rely on continuous import of MYC due to its high turn-over. Acetylation of tubulin impairs this mechanism and enables proteasomal degradation of MYC. M-100 targets almost exclusively B-cell lymphoma cells with high levels of MYC whereas non-tumor cells are not affected. M-100 induces massive apoptosis in human and murine MYC-overexpressing B-cell lymphoma cells. We identified the heat-shock protein DNAJA3 as an interactor of tubulin in an acetylation-dependent manner and overexpression of DNAJA3 resulted in a pronounced degradation of MYC. We propose a mechanism by which DNAJA3 associates with hyperacetylated tubulin in the cytoplasm to control MYC turnover. Taken together, our data demonstrate a beneficial role of HDAC6 inhibition in MYC-dependent B-cell lymphoma.

Confocal laser microscopy without fluorescent dye in minimal-invasive thoracic surgery: an ex-vivo pilot study in lung cancer.

Cancer will be the leading cause of death in a few decades. In line with minimal invasive lung cancer surgery, surgeons loose most of their tactile tissue information and need an additional tool of intraoperative tissue navigation during surgery. Confocal laser microscopy is a well-established method of tissue investigation. In this ex-vivo pilot study, we evaluated an endoscopic confocal laser microscope (eCLM) that does not need any fluorescent dye as a diagnostic tool in non-malignant and malignant pulmonary tissue and distal stapler resection margins, respectively. In seven cases, an eCLM was used for examining pulmonary tissue ex-vivo. Images of non-malignant and non-small cell lung cancer tissue and distal stapler resection margins were characterized in terms of specific signal-patterns. No fluorescent dye was used. Correlations to findings in conventional histology were systematically recorded and described. Healthy lung tissue showed hyperreflectoric alveolar walls with dark alveolar spaces. Hyperreflective nets indicated the tumor stroma; whereas the hyperreflective areas indicated the tumor cell clusters. Compared to adenocarcinoma tissue, tissue from squamous cell carcinoma showed more distinctive hyperreflective stroma nets. eCLM characteristics seen in non-malignant and malignant tissue were also visible in distal stapler resection margins and so therefore it was feasible to distinguish between healthy lung tissue and lung cancer. This pilot study shows that the assessment of pulmonary tissue with this eCLM for minimally invasive surgical approach without any fluorescent dye is feasible. It enables to differentiate between benign and malignant tissue in pulmonary specimen by easy to evaluate and reproducible parameters.

Clinical outcome of short-term compression after sclerotherapy for telangiectatic varicose veins.

BACKGROUND: Sclerotherapy is considered to be the method of choice for the treatment of telangiectatic varicose veins (C1 veins). Whereas the use of compression stockings after sclerotherapy is recommended, little is known about the impact of compression on the outcome of sclerotherapy. The aim of this study was to assess the influence of compression on the outcome of injection sclerotherapy of C1 varicose veins. METHODS: There were 100 legs of 50 consecutive patients with chronic venous insufficiency (C1) included. After randomization per patient, both legs were treated with sclerotherapy in a predefined area of the thigh (measuring 100 cm2), followed by eccentric compression for 24 hours. Group A received no further compression, whereas group B was additionally equipped with compression stockings of 18 to 20 mm Hg above the ankle and continued wearing these for 1 week. Photodocumentation was performed before, 1 week after, and 4 weeks after sclerotherapy, and the clinical outcome was assessed at these postprocedure follow-up dates. The photographs were reviewed by an internal unblinded rater and an independent blinded external rater. RESULTS: There was no discernible difference between the groups in terms of clinical outcome or side effects after 4 weeks. Whereas inter-rater reliability was high, there was no correlation between the raters and patients in terms of outcome. In 55% of the treated legs, the patients deemed the result of the treatment to be good; in 27% of the treated legs, fair; and in 18%, poor. Postprocedure hyperpigmentation occurred in 13% of patients and was comparable in both groups. Compression therapy was found to be comfortable by the majority (58%) of patients. CONCLUSIONS: One week of postinterventional compression therapy had no clinical benefit compared with no compression.

Accuracy evaluation of patient-specific 3D-printed aortic anatomy.

INTRODUCTION: 3D printing has a wide range of applications in medicine. In surgery, this technique can be used for preoperative planning of complex procedures, production of patient specific implants, as well as training. However, accuracy evaluations of 3D vascular models are rare. OBJECTIVES: Aim of this study was to investigate the accuracy of patient-specific 3D-printed aortic anatomies. METHODS: Patients suffering from aorto-iliac aneurysms and with indication for treatment were selected on the basis of different anatomy and localization of the aneurysm in the period from January 1st 2014 to May 27th 2016. Six patients with aorto-iliac aneurysms were selected out of the database for 3D-printing. Subsequently, computed tomography (CT) images of the printed 3D-models were compared with the original CT data sets. RESULTS: The mean deviation of the six 3D-vascular models ranged between -0.73 mm and 0.14 mm compared to the original CT-data. The relative deviation of the measured values showed no significant difference between the 3D-vascular and the original patient CT-data. CONCLUSION: Our results showed that 3D printing has the potential to produce patient-specific 3D vascular models with reliable accuracy. This enables the use of such models for the development of new endovascular procedures and devices.

Laparoscopic resection rectopexy for rectal prolapse: a single-center study during 16 years.

BACKGROUND: Many different techniques to treat rectal prolapse have been introduced. Laparoscopic resection rectopexy has been shown to entail benefits regarding both perioperative results and short-term outcome, whereas data for long-term outcome are scarce. METHODS: Between 1993 and 2008, all laparoscopic resection rectopexies for rectal prolapse II° or III° were selected from a prospective laparoscopic colorectal surgery database. We analyzed demographic, perioperative, and follow-up results. We defined two periods (1993-2000 and 2001-2008) for comparison of data. Long-term follow-up was obtained by sending questionnaires to all patients. Evaluation included constipation, incontinence, and recurrence of prolapse. RESULTS: Between January 1993 and November 2008, we performed 152 laparoscopic resection rectopexies for rectal prolapse. Median age was 64.1 years (± 14.6). Conversion rate was 0.7% (1), mean operation time was 204 (± 65.3) min, and was significantly shorter in the second period compared with the first (P < 0.0001). Mortality was 0.7% (n = 1). Complication rates were 4% (n = 6; major) and 19.2% (n = 29; minor), respectively. Mean length of hospital stay was 11.3 (± 6.4) days and was significantly shorter in the second period compared with the first period (P < 0.0001). Mean time of follow-up was 47.7 (± 41.6) months. Improvement or complete elimination of constipation was stated by 81.3% (65), and improvement or elimination of incontinence was stated by 67.3% (72). Overall recurrence rate was 11.1% (n = 10) with a rate of 5.6% (n = 5) for a 5-year period. Of those patients with previous perineal surgery for rectal prolapse, 53.8% (7/13) experienced recurrent prolapse after laparoscopic resection rectopexy in contrast to 3.9% (3/77) of patients without previous perineal prolapse surgery (P < 0.0001). CONCLUSIONS: Our data support the benefits of laparoscopic resection rectopexy for rectal prolapse regarding both perioperative results and long-term functional outcome. Preceding perineal or open abdominal operations have an impact on recurrence after laparoscopic resection rectopexy.

Feasibility of an endovascular training and research environment with exchangeable patient specific 3D printed vascular anatomy: Simulator with exchangeable patient-specific 3D-printed vascular anatomy for endovascular training and research.

PURPOSE: Endovascular interventions have become standard procedures for the therapy of abdominal aortic aneurysms. Therefore, endovascular surgeons need special skills which have to be learned and trained. Additionally, authentic simulators are needed for further development of new endovascular devices and procedures. The aim of this project was to develop an authentic and modular endovascular simulation environment with patient-specific vascular anatomy for training and research purposes. MATERIAL AND METHODS: We first designed a prototype with exchangeable 3D-printed patient-specific vascular anatomy. Then, the feasibility of the prototype was validated by a simulation of an EVAR procedure in a clinical setting. RESULTS: We developed an authentic endovascular simulator with an exchangeable patient-specific vascular anatomy and performed an EVAR procedure under realistic conditions. The evaluation of the accuracy of the vascular models showed little deviation when compared with the original CT data. CONCLUSION: Endovascular simulators based on patient-specific 3D-printed vascular models can realistically mimic endovascular procedures and have the potential to be used for further development of new devices and grafts as well as for training purposes. Furthermore, in our opinion they can reduce the use of animals during developmental processes.

Three-dimensional guidance including shape sensing of a stentgraft system for endovascular aneurysm repair.

PURPOSE: During endovascular aneurysm repair (EVAR) procedures, medical instruments are guided with two-dimensional (2D) fluoroscopy and conventional digital subtraction angiography. However, this requires X-ray exposure and contrast agent is used, and the depth information is missing. To overcome these drawbacks, a three-dimensional (3D) guidance approach based on tracking systems is introduced and evaluated. METHODS: A multicore fiber with fiber Bragg gratings for shape sensing and three electromagnetic (EM) sensors for locating the shape were integrated into a stentgraft system. A model for obtaining the located shape of the first 38 cm of the stentgraft system with two EM sensors is introduced and compared with a method based on three EM sensors. Both methods were evaluated with a vessel phantom containing a 3D-printed vessel made of silicone and agar-agar simulating the surrounding tissue. RESULTS: The evaluation of the guidance methods resulted in average errors from 1.35 to 2.43 mm and maximum errors from 3.04 to 6.30 mm using three EM sensors, and average errors from 1.57 to 2.64 mm and maximum errors from 2.79 to 6.27 mm using two EM sensors. Moreover, the videos made from the continuous measurements showed that a real-time guidance is possible with both approaches. CONCLUSION: The results showed that an accurate real-time guidance with two and three EM sensors is possible and that two EM sensors are already sufficient. Thus, the introduced 3D guidance method is promising to use it as navigation tool in EVAR procedures. Future work will focus on developing a method with less EM sensors and a detailed latency evaluation of the guidance method.

Crohn's disease-a chameleon during pregnancy.

BACKGROUND: In the past, women with Crohn's disease (CD) as a risk factor in pregnancy were discouraged from becoming pregnant. Today, by contrast, gestation is medically acceptable in these patients despite several severe complications. MATERIALS AND METHODS: We present the course of five female patients with CD requiring surgery during pregnancy and giving birth at our institution between 1998 and 2008. These cases as well as our treatment recommendations for patients wishing to have children and our approaches to the management of complications during pregnancy are discussed in the light of the literature. RESULTS AND CONCLUSION: Three of five women had a preterm delivery (26 to 31 weeks' gestation) with a decreased neonatal weight. Generally, the diagnosis of CD is often delayed and diagnostic errors (four of five women) are not uncommon. The symptoms vary widely and include those typical of pregnancy. Three patients had to have a cesarean and only two patients were able to deliver vaginally. Especially in pregnant patients, the course of the disease is highly variable and difficult to predict. Our experience suggests that patients should be advised to conceive during remission. Indications for surgery in pregnant patients are the same as for nonpregnant women and include perforation, obstruction, hemorrhage, and abscess. The advantages of endoscopic surgery also apply to pregnant patients with acute manifestations. A stoma is not a contraindication to vaginal delivery.