Collaborative Uncertainty Benefits Multi-Agent Multi-Modal Trajectory Forecasting

In multi-modal multi-agent trajectory forecasting, two major challenges have not been fully tackled: 1) how to measure the uncertainty brought by the interaction module that causes correlations among the predicted trajectories of multiple agents; 2) how to rank the multiple predictions and select the optimal predicted trajectory. In order to handle the aforementioned challenges, this work first proposes a novel concept, collaborative uncertainty (CU), which models the uncertainty resulting from interaction modules. Then we build a general CU-aware regression framework with an original permutation-equivariant uncertainty estimator to do both tasks of regression and uncertainty estimation. Furthermore, we apply the proposed framework to current SOTA multi-agent multi-modal forecasting systems as a plugin module, which enables the SOTA systems to: 1) estimate the uncertainty in the multi-agent multi-modal trajectory forecasting task; 2) rank the multiple predictions and select the optimal one based on the estimated uncertainty. We conduct extensive experiments on a synthetic dataset and two public large-scale multi-agent trajectory forecasting benchmarks. Experiments show that: 1) on the synthetic dataset, the CU-aware regression framework allows the model to appropriately approximate the ground-truth Laplace distribution; 2) on the multi-agent trajectory forecasting benchmarks, the CU-aware regression framework steadily helps SOTA systems improve their performances. Especially, the proposed framework helps VectorNet improve by 262 cm regarding the Final Displacement Error of the chosen optimal prediction on the nuScenes dataset; 3) in multi-agent multi-modal trajectory forecasting, prediction uncertainty is proportional to future stochasticity; 4) the estimated CU values are highly related to the interactive information among agents. The proposed framework can guide the development of more reliable and safer forecasting systems in the future.

Correlation Between Sarcopenia and Growth Rate of the Future Liver Remnant After Portal Vein Embolization in Patients with Colorectal Liver Metastases

PURPOSE

To investigate whether sarcopenia and myosteatosis correlate with the degree of hypertrophy (DH) and kinetic growth rate (KiGR) of the future liver remnant (FLR) in patients with colorectal liver metastases undergoing portal vein embolization (PVE) in preparation for right hepatectomy.

MATERIALS AND METHODS

Forty-two patients were included. Total liver volume and FLR volume were measured before and 2-4 weeks after PVE. KiGR of the FLR was calculated. Sarcopenia was assessed using the total psoas muscle volume (PMV), the psoas muscle cross-sectional area (PMCS) and the total skeletal muscle index (L3SMI) at the level of 3rd lumbar vertebra. Degree of myosteatosis was assessed by mean muscle attenuation at L3 (L3MA). Correlations between muscle indices and DH and KiGR were assessed using simple linear regression analyses.

RESULTS

Mean DH was 8.9 ± 5.7%, and mean KiGR was 3.6 ± 2.3. Mean PMV was 55.56 ± 14.19 cm3/m3, mean PMCS was 8.76 ± 2.3 cm2/m2, mean L3SMI was 45.6 ± 9.89 cm2/m2, and mean L3MA was 27.9 ± 18.6 HU. There was a strong positive correlation between PMV and DH (R = 0.503, p = 0.001) and PMV and KiGR (R = 0.545, p < 0.001). Furthermore, there was a moderate correlation between PMCS and KiGR (R = 0.389, p = 0.014). L3SMI and L3MA were neither associated with DH (p = 0.390 and p = 0.768, respectively) nor with KiGR (p = 0.188 and p = 0.929, respectively).

CONCLUSION

We identified a positive correlation between PMV and PMCS, as markers for sarcopenia, and the KiGR of the FLR after PVE. PMV and PMCS might therefore aid to identify patients who are poor candidates for FLR augmentation using PVE alone.

Long-term outcome and quality of life after initial and repeat resection of colorectal liver metastasis: A retrospective analysis

BACKGROUND

Repeat hepatectomy is a widely accepted treatment for patients with recurrent colorectal liver metastasis (CRLM). The aim of this study was to compare initial and repeat hepatic resection concerning overall survival, prognostic factors and postoperative quality of life.

METHODS

Data on patients who underwent initial or repeat hepatic resection for CRLM between 2010 and 2016 were prospectively collected and retrospectively evaluated. Follow-up data, EORTC QLQ-C30 and QLQ-LMC21 questionnaire results for quality of life (QoL) evaluation were analyzed.

RESULTS

160 patients at a median age of 62.8 ± 11.8 years were analyzed. 122 were initially resected and 38 underwent a repeat hepatic resection. Disease-free survival (DSF) was superior in the initial resection group (p < 0.001), while there was no difference in overall survival (OS) (p = 0.288). BMI >30 (p = 0.012), extrahepatic tumor manifestation (p = 0.037), >1 CRLM manifestation (p = 0.009), and perioperative chemotherapy (p = 0.006) in the initial resection group and primary left colon tumor (p = 0.001) in the repeat resection group were identified as prognostic factors in multivariate Cox regression analysis. EORTC QLQ-LMC-21 module symptom score displayed an increased occurrence of a dry mouth in the initial hepatectomy group (p = 0.003). EORTC QLQ-C30 general functioning and symptom scores showed no difference.

CONCLUSION

Repeat hepatic resection for CRLM is as effective as primary surgical treatment in terms of OS and QoL. Patients should be selected carefully concerning prognostic factors as DFS is decreased after repeat hepatic resection.

[Expert recommendations: Hepatitis C and transplantation]

With the approval of new direct acting antiviral agents (DAA), therapeutic options for patients with chronic hepatitis C virus (HCV) infection are now generally available before and after liver transplantation (LT). Interferon-free DAA regimens are highly effective therapies and provide a good safety profile. However, the body of clinical evidence in this patient population is limited and the best treatment strategies for patients on the waiting list with (de)compensated cirrhosis and after LT are not well defined. The following recommendations for antiviral therapy in the context of LT are based on the currently available literature and clinical experience of experts in the field, and have been discussed in an expert meeting. The aim of this article is to guide clinicians in the decision making when treating patients before and after LT with DAAs.

Experiences with multispecies polymerase chain reaction and specific oligonucleotide probes for the detection of Mycoplasma gallisepticum and Mycoplasma synoviae

Amplified fragments of the rDNA coding for 16S rRNA of Mycoplasma gallisepticum (MG) and Mycoplasma synoviae (MS) were blotted on nylon membranes, followed by dot-blot detection with two species-specific digoxigenin-(DIG)-labeled oligonucleotide probes. The sensitivity and specifity of the tests were determined in titration studies with purified homologous and heterologous DNA. With the detection protocol used, the MSYV8/31 probe showed 100% specifity for MS, while both MG and the related species Mycoplasma imitans were recognized by the MGAV8/31 probe. Both DIG-labeled oligonucleotides gave positive results in the colorimetric assay with 10 to 100 ng homologous non-amplified DNA and polymerase chain reaction (PCR) amplificates of 100 fg homologous template DNA. There was no reaction with heterologous strains when amplificates starting with a 106-fold amount of template DNA (100 ng) were tested in dot-blots. The suitability for field samples was demonstrated with tracheal swabs from turkeys and chickens, and the results were compared with mycoplasma growth in cultures of the same swabs. Both tests had an accuracy of over 95%, a high sensitivity and specificity, and high predictive values of positive or negative results. There was no significant difference between the results obtained by the two methods. PCR in combination with dot-blotting is a relatively simple method for the detection of mycoplasma infections, and a valuable extension of current diagnostic tools.

An accelerated dose escalation with a grass pollen allergoid is safe and well-tolerated: a randomized open label phase II trial

Background

The number of injections in the dose escalation of subcutaneous immunotherapy (SCIT) is small for some currently used hypoallergenic allergoids, but can still be inconvenient to patients and can impair compliance. The aim of this trial was to compare safety and tolerability of an accelerated to the conventional dose escalation scheme of a grass pollen allergoid.

Methods

In an open label phase II trial, 122 patients were 1:1 randomized for SCIT using a grass pollen allergoid with an accelerated dose escalation comprising only 4 weekly injections (Group I) or a conventional dose escalation including 7 weekly injections (Group II). Safety determination included the occurrence of local and systemic adverse events. Tolerability was assessed by patients and physicians.

Results

Treatment-related adverse events were observed in 22 (36.1 %) patients in Group I and 15 (24.6 %) in Group II. Local reactions were reported by 18 patients in Group I and 11 in Group II. Five Grade 1 systemic reactions (WAO classification) were observed in Group I and 2 in Group II. Grade 2 reactions occurred 3 times in Group I and 2 times in Group II. Tolerability was rated as “good” or “very good” by 53 (86.9 %) patients in Group I and 59 (100 %) in Group II by investigators. Forty-eight patients in Group I (80.0 %) and 54 in Group II (91.5 %) rated tolerability as “good” or “very good”.

Conclusions

The dose escalation of a grass pollen allergoid can be accelerated with safety and tolerability profiles comparable to the conventional dose escalation.

Doppler Ultrasound and Transient Elastography in Liver Transplant Patients for Noninvasive Evaluation of Liver Fibrosis in Comparison with Histology: A Prospective Observational Study

BACKGROUND AND AIM

Accurate quantification of progressive liver disease is essential for therapeutic decisions and follow-up for patients who underwent liver transplantation. To evaluate the quality of noninvasive assessment of liver fibrosis in these patients, we compared Doppler ultrasound of the hepatic blood vessels as well as transient elastography (TE, FibroScan(®)) with liver biopsy following transplantation.

METHODS

We performed Doppler ultrasound of the hepatic veins, hepatic artery, and portal vein as well as a TE in 48 patients who underwent liver transplantation 12 months ago. Hepatic venous flow was evaluated by determination of the resistance index (HVRI) of the right hepatic vein. Doppler and TE results were compared with histopathologic workup of a 12-month protocol liver biopsy after transplantation.

RESULTS

HVRI showed a high reliability in predicting liver fibrosis stage FII or higher (AUROC of 0.99 ± 0.001 for FII or higher, the HVRI < 1.05 with a sensitivity and specificity of 100 and 91.43 %) compared to histopathologic workup (Desmet's score) and was comparable to TE analysis. Both HVRI and TE differed significantly in no or minimal fibrosis versus FII or higher (p < 0.001). In contrast, portal vein and hepatic artery did not show significant changes in blood flow in our study population.

CONCLUSIONS

Hepatic vein flow resistance index is a valuable tool in noninvasive evaluation of liver fibrosis in liver transplantation follow-up predicting FII or higher and might help reducing the number of protocol biopsies needed.

Immunohistochemical demonstration of connexins in the developing feather follicle of the chicken

Based on immunohistochemistry, the study demonstrates the varying distribution and reaction intensity of connexins (Cx26 [chicken 31sim], 30 [chicken 31], 31, 32, 43, 45) in the developing feather follicle of the chicken (White Leghorn). The different embryonal stages were identified according to the normal table of Hamburger and Hamilton (1951). The development of the feather follicle complex is closely related to skin layer development, making use of the controlling function of connexins. This was evident during feather follicle differentiation, based on communication between ectomesodermal (fibroblasts) and ectodermal cells (developing epidermis), but also by the subsequent separation of the two cell line types related to their connexin-dependent differentiation degree. With the increase in mesenchymal cell numbers during feather placode development, the multiple connexins Cx26 [chicken 31sim] and 43, supported by Cx30 [chicken 31], 31 and 32, were increasingly activating the fibroblast concentrations as related to epidermal follicle buds, the specific follicle structure, the endothelial cells of capillaries and larger blood vessels, as well as the collagen fiber production and the growing feather musculature shortly before hatching; Cx45 could not be demonstrated. In conclusion, it seems that connexin expression is not only coupled to the origin of embryonic cells, but also connected with tissue formation before the follicle system can be formed.

Colonic wall changes in patients with diverticular disease - is there a predisposition for a complicated course?

BACKGROUND

The aim of this study was to evaluate colonic wall changes and enteric neuropathy in patients with either uncomplicated (UDD) or complicated diverticular disease (CDD). Furthermore, we evaluated the presence of an anatomic sphincter at the rectosigmoid junction (RSJ).

METHODS

Samples of colonic tissue from fifteen patients with UDD, fifteen patients with CDD and fifteen patients as control were collected. Collagen quotient I/III was measured with the Sirius-red test, expression of MMP-1, MMP-13, innervation (S100), proliferation (Ki67) and apoptosis (TUNEL) in the colonic wall were investigated by immunohistochemical studies. Furthermore, measurements of the different layers were performed to investigate the RSJ.

RESULTS

Patients with either UDD or CDD had lower collagen I/III quotients compared to the control group, significant for CDD (p = 0.007). For MMP-1 and MMP-13 only a slight increase for patients with CDD was found. The percentage of proliferating (Ki67) and apoptotic (TUNEL) cells was significantly higher for patients with CDD than in the control group (p = 0.016; p = 0.037). Upon investigating the S100-expression a significant reduce in glial cells density was found in the myenteric and mucosal plexus for both groups (UDD and CDD) compared to the control group. Measurements of the different colon layers oral, aboral and at the RSJ revealed equal values.

CONCLUSIONS

This study has shown that colonic wall changes and enteric neuropathy seem to play a role in the pathogenesis of colonic diverticulosis. None of our results suggest a predisposition for a complicated diverticular disease. Furthermore, the presence of an anatomic sphincter at the rectosigmoid junction could not be detected.

Scan-based volume animation driven by locally adaptive articulated registrations

This paper describes a complete system to create anatomically accurate example-based volume deformation and animation of articulated body regions, starting from multiple in vivo volume scans of a specific individual. In order to solve the correspondence problem across volume scans, a template volume is registered to each sample. The wide range of pose variations is first approximated by volume blend deformation (VBD), providing proper initialization of the articulated subject in different poses. A novel registration method is presented to efficiently reduce the computation cost while avoiding strong local minima inherent in complex articulated body volume registration. The algorithm highly constrains the degrees of freedom and search space involved in the nonlinear optimization, using hierarchical volume structures and locally constrained deformation based on the biharmonic clamped spline. Our registration step establishes a correspondence across scans, allowing a data-driven deformation approach in the volume domain. The results provide an occlusion-free person-specific 3D human body model, asymptotically accurate inner tissue deformations, and realistic volume animation of articulated movements driven by standard joint control estimated from the actual skeleton. Our approach also addresses the practical issues arising in using scans from living subjects. The robustness of our algorithms is tested by their applications on the hand, probably the most complex articulated region in the body, and the knee, a frequent subject area for medical imaging due to injuries.

[Conventional reparation of parastomal hernia]

The reparation of parastomal hernias and their recurrence remain problematic although the implementation of mesh techniques has lowered recurrences rates. Conventional surgical techniques include suture repair, relocation of the stoma as well as diverse hernia repair procedures with mesh implantation. Suture repair has been abandoned due to its high recurrence rate. Simple relocation is not recommended because of high rates of recurrent parastomal hernias. Conventional hernia repair using mesh implants is classified according to the mesh position into epifascial (onlay), retromuscular (sublay) and intraperitoneal (IPOM) techniques. Furthermore, a combination of relocation with additional mesh enforcement is also possible. The value of the different mesh techniques and of new biological mesh prostheses must be evaluated in randomized controlled studies.

External iliac artery ligation due to late postoperative rupture after radical lymphadenectomy for advanced ovarian cancer--two case reports

According to the present guidelines for advanced epithelial ovarian cancer (EOC), bulky lymph nodes should be removed as part of the routine surgical staging and the primary goal being removal of all macroscopic tumor residuals. Furthermore, EOC-patients with bulky lymph node relapse seem to benefit from lymphadenectomy in terms of recurrence and overall survival.We present two cases of severe postoperative hemorrhage due to external iliac artery rupture ten and 12 days after radical bulky lymph node removal in primary and recurrent EOC-patients. Both cases were successfully managed by ligation of the two arms of the external iliac artery achieving immediate hemostasis. No crossover bypass was required to maintain lower extremity perfusion. Late rupture of the iliac vessels is a rare complication of systematic lymphadenectomy in EOC. This complication can be managed by unilateral external iliac artery ligation without mandatory subsequent graft interposition or crossover bypass.

Results of liver resection in combination with radiofrequency ablation for hepatic malignancies

INTRODUCTION

Liver tumors should be surgically treated whenever possible. In the case of bilobar disease or coexisting liver cirrhosis, surgical options are limited. Radiofrequency ablation (RFA) has been successfully used for irresectable liver tumors. The combination of hepatic resection and RFA extends the feasibility of open surgical procedures in patients with liver metastases and hepatocellular carcinoma (HCC).

PATIENTS AND METHODS

RFA was performed with two different monopolar devices using ultrasound guidance. Intraoperative use of RFA for the treatment of liver metastases or HCC was limited to otherwise irresectable tumors during open surgical procedures including hepatic resections. Irresectability was considered if bilobar disease was treated, the functional hepatic reserve was impaired or appraised marginal for allowing further resection.

RESULTS

Ten patients with both liver metastases and HCC, and two patients with cholangiocellular carcinoma were treated. Complete initial tumor clearance was achieved in all patients. Two patients of the metastases group and five patients of the HCC group suffered from local recurrence after a median of 12 months (1-26) (local recurrence rate 32%). Five patients of the metastases group and six patients of the HCC group developed recurrent tumors in different areas of the ablation site after a median time of 4 months (2-18) (distant intrahepatic recurrence in 55%). Survival at 31 months was 36%.

CONCLUSION

RFA extends the scope of surgery in some candidates with intraoperatively found irresectability.

Do patients with recurrent ovarian cancer benefit from relative tumor reduction? Results from a prospective study

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Background: Primary cytoreduction is the cornerstone in the management of epithelial ovarian cancer (OC). However, the roles of salvage surgery and of tumor reduction are still discussed controversially. The present study was conducted to assess the impact of secondary tumor reduction surgery on progression-free survival and on overall survival. Methods: Between September 2000 and April 2006, 177 consecutive patients (pts) with a first relapse of OC underwent secondary tumor reduction surgery at our department. The achieved tumor reduction was categorized as 1/5 (20% tumor debulked), 2/5 (40%), 3/5 (60%), 4/5 (80%), or 5/5 (macroscopic tumor-free) and the maximal tumor diameter was also denoted (tumor free, < 1cm, ≥ 1cm). Results: The median age was 56 years (95% CI: 23–83), median follow-up was 10.8 months (95% CI: 1–65). In 79 pts (44.6%) complete macroscopic tumor resection was achieved (median overall survival (OAS) 60.6 months, 21.3–99.8 and median progression-free survival (PFS) 14.9 months, 11.7–18, p < 0.001). In 56 pts (31.6%) 4/5 of the tumor was removed (OAS 15.6 months, 10.3–20.8 and PFS 9 months, 7.2–10.7, p < 0.001), in 13 (7.3%) 3/5 (OAS 21.7 months, no interval and PFS 12 months, 0.0–24.5, p < 0.001) and in 7 (4%) each 2/5 tumor reduction (OAS was 14.2 months, 4.1–24.2 and PFS 11 months, 5.9–16, p < 0.001) and if 1/5 tumor reduction was achieved OAS was 11.1 months, 2–20.1 and PFS 7 months, 2.5–11.4, p < 0.001. Fifteen pts (8.5%) had a bulky unresected disease (OAS 4.7 months, 1.0–8.3 and PFS of 3.7 months, 0–7.6, p < 0.001). From these 98 (55.4%) pts without complete macroscopic tumor resection, 46 were left with <1cm tumor diameter (OAS 17.2 months, 13–21.4 and PFS 9 months, 7.4–10.6 p < 0.001) and 52 with ≥1cm tumor diameter (OAS 8.7 months, 4.2–13.2 and PFS 7 months, 5.8–8.2 p < 0.001). All in all, the median postoperative survival for pts with tumor residuals and any tumor reduction (4/5, 3/5, 2/5. and 1/5 tumor reduction) were better when compared to pts with no tumor reduction (24.8 months vs. 4.7, p < 0.001). Conclusions: Our data demonstrate a significant benefit for salvage surgery if a macroscopic complete tumor resection can be achieved. We could not see any effect of relative tumor reduction on PFS or OAS.

No significant financial relationships to disclose.

Comparative analysis of the sialic acid binding activity and the tropism for the respiratory epithelium of four different strains of avian infectious bronchitis virus

Avian infectious bronchitis virus (IBV) is a major pathogen in commercial poultry flocks. We recently demonstrated that sialic acid serves as a receptor determinant for IBV on the tracheal epithelium. Here we compared the IBV strains Beaudette, 4/91, Italy02, and QX for their sialic acid-binding properties. We demonstrate that sialic acid binding is important for the infection of primary chicken kidney cells and the tracheal epithelium by all four strains. There were only slight differences between the four strains, indicating the universal usage of sialic acids as receptor determinants by IBV. In addition, we analysed the primary target cells in the respiratory epithelium of the four different strains and found that all of them infected ciliated cells and goblet cells.

Evaluation of bone strength, keel bone deformity and egg quality of laying hens housed in small group housing systems and furnished cages in comparison to an aviary housing system

Abstract. The objective of the study was to assess bone breaking strength, keel bone status and egg quality parameters of Lohmann Silver (LS) and Lohmann Tradition (LT) layers housed in small group systems (SG) and furnished cages (FC) in comparison to an aviary system. At the end of the 3rd, 6th, 9th and 11th laying month, approximately 40 hens were randomly chosen from each housing system and slaughtered (478 hens in total). Humerus and tibia strengths were analysed using a three-point-bending machine. Keel bone status was evaluated on a scale from 1 (severe) to 4 (no deformity). Shell breaking strength was measured every four weeks, totalling 4,887 eggs. Statistical analyses were performed using the MIXED procedure of SAS. Humerus and tibia strengths of LS layers housed in SG were significantly higher compared to LS hens kept in FC. Bone breaking strengths of humerus and tibia in LS and LT layers were highest in the aviary system and the differences to the other housing systems were significant. No significant differences in tibia and humerus bone breaking strengths were found between SG and FC for LT hens. Keel bone status was not significantly influenced by housing system or laying strain. For both hybrids, shell breaking strength was significantly lower in SG compared to FC and aviary system. The results showed that SG systems can significantly enhance bone breaking strength for LS layers in comparison to hens kept in FC. The lower shell breaking strength of eggs in SG might slightly impair economic aspects.

[New approaches to early detection, estimation of prognosis and therapy for malignant tumours of the gastrointestinal tract]

Tumours of the gastrointestinal tract are the single largest group of malignant tumours of humans accounting for approximately 2 million new cases and over 1.2 million deaths annually. They are most commonly a disease of the elderly, and their relative and absolute frequency will rise continuously due to an ageing population. This explains why the prevalence of gastric cancer increases in spite of a decreasing incidence. Gastrointestinal tumours will remain a major clinical and health economical challenge. The prognosis is often dismal. Most of these cancers are diagnosed in an advanced stage, which prohibits curative treatment and limits treatment options. In order to circumvent these problems, we need to develop strategies that allow identification of at-risk patients and tumours at an early stage, and raise the compliance in the general population for screening programmes. There is a great need in clinics for prognostic and predictive biomarkers that are able to tailor patient treatment at different stages of the disease.

Reproducibility of swollen sinuses in broilers by experimental infection with avian metapneumovirus subtypes A and B of turkey origin and their comparative pathogenesis

Swollen head syndrome (SHS) associated with avian metapneumovirus (aMPV) subtype A or subtype B in broilers and broiler breeders has been reported worldwide. Data about pathogenesis of aMPV subtypes A and B in broilers are scarce. It has been difficult to reproduce swollen sinuses in chickens with aMPV under experimental conditions. In the field, SHS in broilers is suspected to be induced by combined infections with different respiratory pathogens. The objectives of the present study were to compare the pathogenesis of subtypes A and B aMPV in commercial broilers and to investigate the reproducibility of clinical disease. In two repeat experiments, commercial broilers free of aMPV maternal antibodies were inoculated with aMPV subtypes A and B of turkey origin. The clinical signs such as depression, coughing, nasal exudates, and frothy eyes appeared at 4 days post inoculation, followed by swelling of periorbital sinuses at 5 days post inoculation. Higher numbers of broilers showed clinical signs in subtype-B-inoculated compared with subtype-A-inoculated groups. Seroconversion to aMPV was detectable from 10 to 11 days post inoculation. The appearance of serum aMPV enzyme-linked immunosorbent assay antibodies and the clearance of the aMPV genome coincided. Subtype B aMPV showed a broader tissue distribution and longer persistence than subtype A. Histopathological changes were observed in the respiratory tract tissues of aMPV-inoculated broilers, and also in paraocular glands, such as the Harderian and lachrymal glands. Overall, our study shows that representative strains of both aMPV turkey isolates induced lesions in the respiratory tract, accompanied by swelling of infraorbital sinuses, indicating the role of aMPV as a primary pathogen for broilers.

[Composting of poultry carcasses as an alternative method for disposal in case of an outbreak of an epizootic disease: first results]

Composting of poultry carcasses represents an alternative method for disposal in case of an outbreak of an epizootic disease. Two composting experiments, each with a different construction of the compost pile, were carried out in a stable. In the first experiment two layers of turkey carcasses were formed. This compost pile covered with straw was directly built on the ground. In the second experiment no layers of carcasses were formed, and it was assembled on straw bales covered with plastic foil. One part of this compost pile was covered with straw, the other one was additionally covered with plastic foil. In the first experiment in the upper layers of the compost pile temperatures of up to 54.9 degrees C were reached and the decomposition of carcasses was very advanced with no soft tissues remaining after 30 days. In contrast temperatures of only 45.2 degrees C were reached in the lower layers and decomposition was far less advanced. This difference in decomposition was most likely caused by the temperature difference observed. In the second experiment the near complete decomposition seen in the upper layers of the compost pile at the first trial, was not achieved. Decomposition was more advanced in the straw covered part of this compost pile than in the part covered with straw and plastic foil. On the other hand, higher temperatures of up to 48.4 degrees C were measured in the lower layers of this compost pile most likely as a result of the increased heat insulation in particular to the ground.

Creating an animatable 3D volume hand model from in vivo MRI

Volume graphics has obvious benefits to medical visualization, since it represents the complete 3D information of both surface appearance and the underlying anatomical structures. This study presents an approach to rapidly creating an animatable 3D volume from in vivo human hand MRI scans. The result is a fully articulated hand volume driven by intuitive joint control that respects rigid deformation of the bone structures and produces smooth deformations of both the skin surface and the interior soft tissue regions. While the method can potentially be applied to any articulated body region, the human hand is chosen to illustrate the process, both due to its intrinsic interest in medical applications and because of the large number of degrees of freedom and challenging anatomy of the hand.

Surgical techniques for resectable pancreatic cancer

Pancreatic cancer is a highly aggressive cancer with a rising incidence in most European countries. Due to both the aggressive biology of the disease and the late diagnosis in many cases, pancreatic duct carcinoma is still a disease with a poor prognosis. Today, surgical resection of localized tumor remains the only potentially curative option available for these patients. Advances in surgical techniques and perioperative care has improved significantly in the last 20 years, causing an extension of indications for surgical intervention. However, despite new diagnostic techniques, the surgical exploration still plays the key role for the finally assessment of resectability. For evaluation of local resectability, laparoscopy alone cannot generally be recommended today and explorative laparotomy is required. Contraindications for pancreatic resection are liver metastasis, peritoneal metastasis, and tumor infiltration of visceral arteries. The surgical management of pancreatic cancer consists of two phases: first, assessment of tumor resectability and second, if resectability is given, the pancreaticoduodenectomy with consecutive reconstruction. Standard surgical strategies are the classic pancreaticoduodenectomy including a distal gastrectomy and the pylorus-preserving pancreaticoduodenectomy (PPPD) preserving antral and pyloric function, respectively. Both surgical procedures are equally effective for the treatment of pancreatic carcinoma. Delicate lymphadenectomy during pancreaticoduodenectomy is important for radical oncological enforcement. An extended lymphadenectomy showed no benefit in several trials. Despite the encouraging advances in surgical treatment, actuarial 5-year survival rates after pancreatic resection are only at about 20%.

Liver resection for metastases from renal cell carcinoma

BACKGROUND

This study was conducted to evaluate the safety and efficacy of liver resection in patients with hepatic metastases from renal cell carcinoma and to identify selection criteria for patients suitable for resection.

METHODS

Between January 1988 and March 2006, 31 patients underwent liver resection for metastases from renal cell carcinoma. Patients were identified from a prospective database and retrospectively reviewed. Patient, tumor, and operative parameters were analyzed for their influence on long-term survival.

RESULTS

The overall 1-, 3- and 5-year survival rates were 82.2%, 54.3%, and 38.9%, respectively. One patient was deceased and 4 developed complications during the postoperative course. In the univariate analysis, site of the primary tumor (P = 0.013), disease-free interval (P = 0.012), and resection margins (P = 0.008) showed significant influence on long-term survival. In the multivariate analysis, only the resection margins were identified as an independent prognostic factor after liver resection.

CONCLUSIONS

Liver resection is effective and safe in the treatment of patients with hepatic metastases from renal cell carcinoma and offers the chance of long-term survival and cure. Achieving a margin-negative resection is the most important criterion in the selection of suitable patients for liver resection. However, the number of patients in the present study was small, and investigations of larger series may provide further prognostic parameters in these patients.

Extended resections of liver metastases from colorectal cancer

BACKGROUND

Indications for resection of liver metastases from colorectal cancer and surgical strategies are still under debate.

METHODS

We have retrospectively reviewed the outcome of 660 patients after 685 liver resections for metastases of colorectal cancer in our institution from 1988 to 2004. All surviving patients have a minimum follow-up period of 1 year. The longest follow-up in these patients is 16 years. Three different time periods of 5 to 6 years each were analyzed.

RESULTS

The 30- and 60-day mortality rates were 1.5% (n = 10) and 2.2 % (n = 15), respectively. The rate of formally curative (R0) resections was 84%. Five-year survival rates in all patients and in patients after R0 resection were 37% and 42%, respectively. If only resections from 1999 to 2004 were considered, 5-year survival in patients after R0 resection was 50%. In a multivariate analysis, surgical radicality, ligamental lymph node involvement, number of liver metastases, and time period, in which the liver resection had been performed, were independent prognostic parameters.

CONCLUSIONS

Outcome after liver resection for metastases from colorectal cancer has constantly improved. A formally curative resection is the most relevant prognostic parameter. Number of liver metastases and, in the few patients concerned, lymph node infiltration of the hepatoduodenal ligament, were further prognostic parameters.

Role of multivisceral cytoreductive surgery in patients (pts) with recurrent ovarian cancer (ROC): Who will not benefit from radical tumor debulking?

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Background: Despite improvement in surgery and adjuvant chemotherapy most pts with ovarian cancer (OC) experience a relapse within 2 years after first diagnosis. For primary OC a standard concensus on optimal staging and surgical guidelines is established. The role of radical tumor debulking surgery in ROC is not clearly defined. Aim of this study was to analyze clinical parameters for prediction of operability and impact on overall survival in ROC. Methods: Within the framework of the international project “Tumor bank Ovarian Cancer“ (TOC) a systematic prospective surgical and histomorphological tumor documentation for ROC was performed. Results: Between september 2000 and december 2006, 307 multivisceral operations on 254 pts with ROC were performed consecutively in our department. Median age was 55 years (19–83), median follow-up 15 months (1–75). 34.8% of pts experienced first relapse of OC. Overall, 96.3% of pts received a platinum-based first-line chemotherapy, whereas 73.4% were platinum sensitive. In 55% of pts first relapse surgery was performed. In 41.4% of pts complete macroscopic tumor resection was achieved, associated with a significantly better recurrence-free (median 20.6 vs 13.2, p=0.001) and overall survival (median 42 vs 12 months, p<0.001) compared to pts with any postoperative residual tumor. In multivariate analysis, complete tumor resection was associated with the absence of tumor burden in the upper abdomen (p=0.001) and absence of ascites (p=0.05). Prognostic factors for postoperative survival were: tumor resection (0 cm vs > 0 cm, p<0.001), intraoperative volume of ascites (0 ml vs > 0 ml, p=0.006) and response to platinum-based first-line therapy (platinum sensitive vs platinum-resistant, p=0.006). Conclusions: Radical tumor debulking in patients with ROC is associated with a low postoperative morbidity and mortality. Complete mascroscopic tumor resection is correlated with a significant better long-term prognosis and influenced by tumor spread and presence of ascites. Pts with ROC will not benefit from multivisceral cytoreductive surgery in case of platinum resistance to first-line chemotherapy, presence of intraoperative ascites and postoperative residual tumor.

No significant financial relationships to disclose.

Repeat liver resection for recurrent liver metastases from colorectal cancer

AIMS

Numerous patients suffer from recurrence after resection of liver metastases from colorectal cancer. Recurrence is frequently restricted to the liver and repeat liver resection may offer a curative option in these patients. This study was conducted to clarify safety and effectiveness of this treatment and to identify prognostic factors of a favourable outcome after repeat hepatectomy.

METHODS

Between January 1988 and March 2006 in our institution 811 patients underwent 841 liver resections for metastases from colorectal cancer. Among these, 94 patients underwent a repeat hepatectomy. Patients were identified from a prospective database and retrospectively reviewed. Results of different time periods were assessed and prognostic factors for a favourable outcome were determined.

RESULTS

The perioperative morbidity and mortality was 24% (23 of 94) and 3% (3 of 94), respectively. The one-, three-, five- and ten-year survival for all patients in this series was 89%, 55%, 38% and 23%, respectively. In the univariate analysis, pT-stage of the primary, diameter of the largest metastases, surgical radicality, period of resection and distribution of metastases showed statistically significant influence on survival. The multivariate analysis revealed only pT-stage of the primary tumour, surgical radicality and period of resection as independent prognostic factors.

CONCLUSIONS

Repeat hepatectomy is a safe and effective treatment for recurrent liver metastases from colorectal cancer. Perioperative risk and long-term survival were similar when compared to the results obtained during the initial resection. Achieving a curative resection is the most relevant prognostic factor for a favourable prognosis after repeat liver resection.

Die laparoskopische Appendektomie in der Schwangerschaft

BACKGROUND

Acute appendicitis is the most common cause of an acute abdomen in pregnancy. However, due to the potential fetal risk associated with the CO2-pneumoperitoneum and various operative technical reasons there is still controversy about the role of laparoscopic appendectomy in pregnant women.

PATIENTS AND METHODS

Between January 2000 and November 2005, 283 women between 17 and 45 years with suspected appendicitis underwent laparoscopic appendectomy at our institution. Fifteen of these patients (5.3 %) were pregnant at the time of surgery (mean age, 28 years; range, 18-40 years; mean gestational age, 21.9 weeks; range, 14-34 weeks). Perioperative obstetric monitoring included fetal ultrasound, including Doppler sonography and cardiotocography. Clinical data were collected prospectively. Complete follow-up data were available in 14 patients.

RESULTS

All 15 patients underwent successful laparoscopic appendectomy. Mean operation time was 53 minutes (range, 30-100 minutes). The histologic appendicitis / appendectomy ratio was 73 %. One patient showed a postoperative pyelonephritis, another a cystitis. Average length of hospital stay was 5.5 days (range, 3-10 days). All fourteen pregnancies with complete follow-up resulted in delivery of healthy infants. The mean gestational age at delivery was 39.6 weeks (range, 35-42 weeks). Two patients (14.3 %) had a preterm delivery at 35 weeks with uncomplicated outcome. One patient underwent caesarean section at 41 weeks after chorioamnionitis.

CONCLUSIONS

Laparoscopic appendectomy is a safe and effective method to treat acute appendicitis in pregnant women regardless of the trimester. For the best outcome the operation should be performed in a center where surgeons, perinatologist, obstetricians and anesthesiologists work together as a part of an interdisciplinary team.