Image quality and safety of automated carbon dioxide digital subtraction angiography in femoropopliteal lesions: Results from a randomized single-center study.

PURPOSE: To evaluate the image quality and the safety of automated carbon dioxide (CO2) digital subtraction angiography (DSA). MATERIALS AND METHODS: Fifty patients receiving DSA for femoropopliteal peripheral arterial disease (PAD) were enrolled in this single-center prospective study. All patients received iodinated contrast media (ICM) and CO2 as a contrast agent in the same target lesion. As a primary endpoint, four raters independently evaluated the angiography images based on overall image quality, visibility of collaterals, and assessment of stenoses/occlusions. Inter-rater agreement was assessed using the intraclass correlation coefficient (ICC) and differences between the raters were evaluated using Friedmann's test. Secondary endpoints were procedure safety and patient pain assessment. RESULTS: Inter-rater agreement between CO2-DSA and ICM-DSA images was fair to excellent for overall image quality (ICC: 0.399-0.748), fair to excellent for the visibility of collaterals (ICC: 0.513-0.691), and poor to excellent for the assessment of stenoses/occlusions (ICC: -0.065-0.762). There were no significant differences between the raters. Two patients had a hematoma, one reported pain related to puncture, one became nauseous, and one vomited. No other adverse events were observed. Reported pain scores were significantly higher for CO2-DSA vs. ICM-DSA (1.25 vs. 0625; p < 0.028). CONCLUSION: CO2-DSA using automated injection system in combination with proprietary post-processing software is safe and comparable diagnostic test compared to ICM-DSA.

[Intraoperative completion diagnostics in open vascular surgery]. / Intraoperative Diagnostik in der offenen Gefäßchirurgie.

Intraoperative imaging diagnostics during open vascular surgical procedures aim to enhance diagnostic certainty during the operation, ensure quality control documentation and reduce avoidable complications; however, the evidence for the various diagnostic imaging procedures with respect to improvement of perioperative outcome is not confirmed for carotid endarterectomy or for infrainguinal bypass surgery. Nevertheless, an intraoperative diagnostic control is principally recommended. The advantage of intraoperative imaging is confirmed and essential for the surgical reconstruction of bypass occlusions and acute thromboembolic occlusions.

[Benign liver tumors : Diagnostics and treatment]. / Benigne Lebertumoren : Diagnostik und Behandlung.

Benign liver tumors are often detected during routine ultrasound examinations or as an incidental finding in radiological imaging. Only very few benign liver tumors are at risk of becoming malignant. In the majority of cases the differentiation from malignant tumors is currently carried out using imaging procedures. In a few cases of diagnostic uncertainty, a transcutaneous liver biopsy can lead to clarification. If the suspicion of malignancy is substantiated or this cannot be excluded with absolute certainty, the tumor should be removed by partial liver resection.

[Prerehabilitation in frail patients : Frailty as a risk factor]. / Prärehabilitation gebrechlicher Patienten : "Frailty" als Risikofaktor.

The German population is aging in accordance with the worldwide trend; however, in comparison to most other industrial countries the number of disease-free years of life gained by patients is significantly lower in Germany. Subsequently, the number of hospitalizations and necessary surgical treatment for older and especially frail patients is significantly increasing. Several frailty scoring systems have been published with the aim of improving the assessment of the perioperative risk for these patients; however, these systems for risk assessment have not yet become clinical routine in surgery and therefore this group of frail patients remains underdiagnosed in the field of surgery. Frail patients in particular often need individualized treatment or the adaptation of standard of perioperative care. It has already been clearly shown that frail patients have a markedly higher incidence for certain risk factors (e.g. postoperative delirium, hypovolemia, pharmacological side effects and drug interactions). Additionally, malnutrition is common at the time of hospital admission in up to 70% of this patient group. If not recognized and treated accordingly all these risk factors lead to a compromised rehabilitation, higher complication rates, a prolonged length of hospital stay and a higher mortality. Special preoperative risk assessment scores, which highlight physical, psychological and social evaluation should be widely implemented in surgical departments. A standardized risk assessment embedded in evidence-based prerehabilitation programs and implemented in geriatric surgery centers can help to improve the outcome in this group of fragile patients.

[Benign liver tumors : Diagnostics and treatment]. / Benigne Lebertumoren : Diagnostik und Behandlung.

Benign liver tumors are often detected during routine ultrasound examinations or as an incidental finding in radiological imaging. Only very few benign liver tumors are at risk of becoming malignant. In the majority of cases the differentiation from malignant tumors is currently carried out using imaging procedures. In a few cases of diagnostic uncertainty, a transcutaneous liver biopsy can lead to clarification. If the suspicion of malignancy is substantiated or this cannot be excluded with absolute certainty, the tumor should be removed by partial liver resection.

[Surgical treatment of peritoneal metastases of colorectal cancer]. / Chirurgische Therapie der Peritonealkarzinose kolorektaler Karzinome.

Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) may significantly improve overall survival in selected patients with peritoneal metastases of colorectal cancer. For good oncological results complete macroscopic cytoreduction is crucial; furthermore, a linear correlation between peritoneal tumor load, as determined by the peritoneal cancer index (PCI) and overall survival has been demonstrated; therefore, surgical treatment should be initiated as early as possible. Synchronous resection of up to three liver metastases may be performed safely and with good results and no influence on the morbidity. With respect to intraperitoneal chemotherapy, mitomycin C and oxaliplatin are most commonly used and may be regarded as equal; however, for perioperative chemotherapy study results are so far inconclusive with some trials hinting at decreased overall survival following neoadjuvant chemotherapy. Adjuvant therapy is likely to improve overall survival if at least 6 cycles are applied. Early detection of peritoneal metastases is difficult at present but might be facilitated in the future by the use of liquid biopsies, which may detect circulating free tumor-specific DNA or RNA. In the meantime, planned second-look laparotomy should be considered for patients at high risk of peritoneal recurrence. In addition, several international studies are currently evaluating the concept of adjuvant or prophylactic HIPEC. The CRS and HIPEC may be repeated in cases of recurrence and should be considered in suitable patients, applying the same criteria as for primary CRS and HIPEC. A recurrence-free interval of >2 years is associated with a significantly better prognosis.

[Liver Transplantation as Treatment for Rare Diseases in Adults]. / Lebertransplantation als Therapie von seltenen Erkrankungen beim Erwachsenen.

In addition to the main indications pertaining to 95 % of all patients receiving liver transplantation in Germany, there are numerous other diseases that may become clinically evident in the adult age and may lead to the decision for liver transplantation. These may be metabolic diseases with their main defect located in the liver, malformations of liver cells, hepatic vascular diseases and rare tumours of the liver. Standard exceptions for the listing are in place only for a limited number of diseases. Exact diagnostics and the point in time for transplantation are crucial for the prognosis.

Which factors affect the long-term survival of patients with hepatocellular carcinoma UICC stage IV?

AIM: In the 7th edition of the TNM classification, not only HCC with distant metastases but also those with regional lymph node metastases are classified as stage IV. MATERIALS AND METHODS, RESULTS: From our prospectively recorded tumor registry, 138 patients (17 %) with HCC were in stage IV. Among those were 68 and 70, respectively, in stage IVA (regional lymph node metastases) and IVB (distant metastases). The tumors were less frequently treated with resection or local ablative treatment (chemoembolization, RFA, SIRT, percutaneous radiation) than patients in stage I-III. Ten HCCs were resected. Five of the resected patients were in stage IVA and five in stage IVB. After tumor resection, patients lived longer than those who underwent local or systemic treatment only (p = 0.003 or p = 0.001, respectively). In the univariate survival analysis, the stage IV patients' long-term survival was decreased statistically significantly through elevated bilirubin, low albumin, Okuda stage III and BCLC stage D. Patients' age and sex, pre-treatment AFP level, Child stage and the presence of venous invasion did not influence survival. In the multivariate analysis (Cox regression), tumor resection and BCLC stage were independent prognostic factors. CONCLUSION: Patients with HCC in TNM stage IV have a very poor prognosis. Only few patients are eligible for resection because of the extent of tumor growth, comorbidities and general condition. These, however, benefit markedly from tumor resection with lymph node dissection and possibly resection of distant metastases.

Acute mesenteric ischemia following cardiovascular surgery--A nested case-control study.

INTRODUCTION: Acute mesenteric ischemia is a rare but often fatal complication following cardiovascular surgery. Early suspicion may reduce overall mortality. This retrospective study aims to identify predictors and risk factors that may determine the onset and evolution of acute mesenteric ischemia. METHODS: In a retrospective case-control study, we compared co-morbidities and peri-operative risk factors of patients with or without mesenteric ischemia following cardiac surgery using univariate and logistic regression analyses. RESULTS: Of 9385 patients, 108 (1.15%) were diagnosed with acute mesenteric ischemia within two weeks after cardiac surgery. In-hospital mortality was 68% for this group. Patients with ischemia and controls were matched in regard to patient's age and type of surgical intervention and showed similar pre-operative parameters. Only liver cirrhosis (OR 13.3, CI95% 3.6-49.3), and emergency operation (OR 2.6, CI95% 1.3-5.2) remained independent pre-operative predictors for acute mesenteric ischemia in multivariate analysis. In contrast, early postoperative parameters revealed a higher correlation with the occurrence of mesenteric ischemia including the use of norepinephrine (OR 3.5 CI95% 1.6-7.8), epinephrine (OR 2.0, CI95% 1.1-3.7), and serum lactate levels >3 mmol/L (OR 2.9, CI95% 1.5-5.6). A set of key markers of regression analysis was evaluated in a ROC curve analysis. The area under curve was 0.835, which indicates moderate to good prognostic accuracy. CONCLUSION: Early identification of pre- and post-operative predictors including liver cirrhosis, emergency operation, serum lactate >3 mmol/L, and the use of norepinephrine and epinephrine may help facilitate early diagnosis of acute mesenteric ischemia following cardiac surgery, and thus may allow immediate adequate treatment, leading to a reduction in mortality rates.

[Aneurysms of the thoracic and thoracoabdominal aorta]. / Aneurysmen der thorakalen und thorakoabdominalen Aorta.

The incidence and operations of thoracic and thoracoabdominal aortic aneurysms have significantly increased. The indications for repair are considered to be a diameter of 6 cm or more and 5.5 cm for patient groups with increased risk of rupture. Complex open surgical repair is associated with significant mortality and complication rates. Total or hybrid endovascular repair seems to reduce early postoperative complications and mortality. The endovascular approach has evolved to be a good and predominant alternative to open repair of these aneurysms for older and high-risk patients as well as for aneurysms with optimal morphological suitability. Notwithstanding, at present a complete paradigm shift from open to endovascular repair for all patients, especially those with complex aneurysms, cannot yet be established.

[Liver transplantation with living donor : current aspects, perspectives and significance in Germany]. / Lebertransplantation mit Lebendspende : Aktuelles, Perspektiven und Stellenwert in Deutschland.

More than 20 years ago living donor liver transplantation was introduced into clinical practice. Specifics of this method were developed initially for children and later on for adults particularly in regions where a liver transplantation program using deceased donors was not readily available. The most sensitive aspect of living donation, namely the danger to a healthy relative in order to perform the transplantation is immanent in the system and, thus, it is definitively a secondary option as compared to deceased organ donation. Following worldwide initial euphoria the numbers have markedly decreased in the western world since the start of the new millennium. In Asian countries in particular, much work has been done to optimize the procedure so that the donor safety and the outcome quality for the recipient have been impressively demonstrated in large patient populations. There is still a severe donor organ shortage and the option to allocate an optimal (partial) organ on an individual basis by living donation has given new impact to the discussion about a further rise in the profile of living donations here as well. The new version of the German transplantation legislation implemented in summer 2012 requires a number of conditions with respect to insurance for living donors. The current state and perspectives are presented here.

[Vascular grafts as access for hemodialysis]. / Prothetische Gefässzugänge für die Hämodialyse.

Prosthetic arteriovenous grafts have an inferior patency rate and greater morbidity than those with autogenous vessels and are therefore considered as secondary or tertiary vascular access for hemodialysis in patients with fatigued or unsuitable superficial arm veins. Prior access planning in accordance of patient characteristics, careful operative procedure and appropriate revision of complications can ensure long-term functioning of a vascular access using a large variety of possible prosthetic conduits. Arteriovenous grafts remain essential in vascular access surgery and their role may be increasing with higher comorbidities of patients and should be preferred to tunnelled cuffed catheters. This article reviews the indications, alternative configurations and characteristics of arteriovenous grafts.

Downsizing a tumor thrombus of advanced renal cell carcinoma with neoadjuvant systemic therapy and resulting histopathological effects.

BACKGROUND: We report a treatment option in surgical therapy of locally advanced renal cell carcinoma (RCC). METHOD: A 63-year-old patient with locally advanced RCC including an atrial thrombus underwent 2 cycles of neoadjuvant therapy (Sutent 50 mg daily for 4 weeks followed by 2 weeks off) and then tumor surgery. Primary surgical therapy had to be delayed because of suspected bronchial carcinoma and additional diagnostics. After neoadjuvant therapy to downsize the tumor thrombus and exclusion of any additional malignant tumors, operation was done via abdominal access; no sternotomy was necessary. RESULTS: Histopathological examinations of the primary tumor after tyrosine kinase inhibitor therapy were evaluated and compared to tumor biopsy material taken before therapy. CONCLUSION: Neoadjuvant therapy with Sutent may represent a favorable treatment option in cases of locally advanced clear-cell RCC with extended tumor thrombus.

[Endovascular treatment of aneurysms after implantation of an aortic-femoral homograft bypass]. / Endovaskuläre Aneurysmaausschaltung nach aortofemoraler Homograftimplantation.

CASE REPORT: We report on two rare endovascular procedures concerning aneurysmatic complications of arterial homografts. In both cases infected aortobifemoral grafts were explanted und replaced by cryopreserved aortofemoral homografts on the left side. The revascularisations on the right side were performed with the deep femoral vein in one case, and by desobliteration of the iliac artery in the other case. After 4 and 10 months, respectively, we found aneurysmatic enlargements of the aortic anastomoses. In both cases we excluded a false aortic aneurysm by uniiliac stentgrafts in combination with a femoro-femoral cross-over bypass for the contralateral leg. Both operations were carried out successfully. However, one patient developed an infection of the stent graft. We explanted the stent graft und performed an aortobifemoral bypass procedure with arterial cryopreserved homograft once again. CONCLUSIONS: Both aneurysmatic complications after aortofemoral homograft implantation could be treated successfully by an endovascular approach. Possible late complications caused by the implantation of homografts or by endovascular procedures can be only detected in due time by a follow-up at short intervals.

Comparison of Two Different Arteriovenous Anastomotic Forms By Numerical 3D Simulation of Blood Flow.

Anastomotic intimal hyperplasia caused by unphysiological hemodynamics is generally accepted as a reason for dialysis access graft occlusion. Optimizing the venous anastomosis can improve the patency rate of arteriovenous grafts. The purpose of this study was to examine, evaluate and characterize the local hemodynamics, and in particular, wall shear stresses in conventional venous end-to-side anastomosis and in patch form anastomosis (Venaflotrade mark) by Computational Fluid Dynamics (CFD). The flow simulations were carried out as three-dimensional to extend results of our previous 2D studies. The numerical simulation was done with a finite volume-based algorithm. The anastomotic forms were constructed with usual size and fixed walls. Subdividing the flow domain into multiple control volumes solved the fundamental equations. The boundary conditions were constant for both forms. The velocity profile of the patch form is better than for the conventional form. The region of high static pressure caused on flow stagnation is reduced on the vein floor. The anastomotic wall shear stress is decreased. The results of this study strongly support patch form use to reduce the incidence of intimal hyperplasia and venous anastomotic stenoses.

Effect of intravenous iloprost and alprostadil (PGE1) on peripheral resistance during femoro-distal reconstructions.

BACKGROUND: A prospective, randomised study was undertaken to investigate the effect of intravenous infusion of either iloprost, the stable prostacyclin (PGI2) analogue, or alprostadil (prostaglandin E1) on peripheral resistance (PR) during femoro-distal reconstruction. METHODS: A prospective randomised study was performed with 35 patients. The PR Measurement of peripheral resistance involved a silicon tube temporarily inserted between the donor and recipient vessel. A flowmeter probe and a pressure transducer were inserted into the tube. The peripheral resistance was calculated as a quotient of pressure and flow under approximate physiological conditions. Patients received either alprostadil (4.4 ng/min/kg) or iloprost (2 ng/min/kg) intravenously over ten minutes. After the end of the infusion, the measurements were taken for five minutes. RESULTS: Baseline peripheral resistance was similar for both groups (iloprost 0.76+/-0.54 mmHg/ml/min, alprostadil 0.72+/-0.35 mmHg/ml/min, p>0.05). Following the measurement procedure, the final peripheral resistance in the iloprost group was reduced (0.57+/-0.33 mmHg/ml/min), but the difference to the alprostadil group (0.70+/-0.36 mmHg/ml/min) was not significant (p>0.05). The different decrease of ratio peripheral resistance (quotient between final and baseline resistance times one hundred) was highly significant (iloprost: 79.4+/-13.4% vs alprostadil: 97.0+/-15.6%, p<0.01). CONCLUSIONS: Intravenous application of prostanoids, infused with usual doses over ten minutes during femoro-distal reconstructions, produces significant differences in decrease of peripheral resistance. Alprostadil only causes a slight drop of resistance, whereas iloprost causes a significant higher reduction of peripheral resistance.

K-ras mutations in stools and tissue samples from patients with malignant and nonmalignant pancreatic diseases.

Mutant-enriched PCR and reverse dot blot hybridization in microplates were applied for examining K-ras status in stools and tissue samples from patients with pancreatic tumors and chronic pancreatitis. In tissue samples, K-ras mutations were found in 32 of 35 cases of ductal adenocarcinoma, in 5 of 7 periampullary cancers, in 1 cystadenocarcinoma, and in 3 of 5 patients with chronic pancreatitis. In stools, mutated K-ras was seen in 10 of 25 cases of ductal adenocarcinoma, in 1 case of cystadenocarcinoma, and in 2 of 6 cases of chronic pancreatitis. These data indicate that the K-ras status of stool samples may help identify pancreatic carcinoma and persons at risk for cancer development; however, it does not allow discrimination of malignant from nonmalignant diseases.

A microplate assay for K-ras genotyping.

The paper presents a microplate hybridisation assay for the detection of codon 12 mutations of the K-ras protooncogene. Single-stranded target DNA, obtained from amplifying sample DNA with 5'-biotin and 5'-digoxigenin-labelled primers and subsequent strand separation, is hybridised with solid phase-fixed capture probes complementary to wild-type and mutated forms of K-ras. After stringent washing the duplex DNA is detected by an ELISA-like protocol incorporating photometric, fluorometric or luminometric detection. Application examples are shown in which the K-ras status was examined in peripheral blood cells, cell cultures, fresh and paraffin-embedded tumour tissue and in stool samples.

[Cystic tumors of the pancreas]. / Cystische Tumoren des Pankreas.

Cystic neoplasms of the pancreas are rare but in the last years more frequently detected. Within a 10-year-period we treated 30 patients, including 8 serous cystadenomas, 6 mucinous cystadenomas, 12 mucinous cystadenocarcinomas, 2 cystic neuro-endocrine tumors and 1 papillary cystic tumor respectively acinar cell cyst-adenocarcinoma. 80% of the patients had symptoms, experienced abdominal pain, weight loss, weakness or abdominal mass. In eight patients the tumors had been misdiagnosed as a pancreatic pseudocyst. The correct type of cystic tumor was diagnosed by preoperative investigations only a few cases. All patients with serous or mucinous cystadenomas are well and without evident recurrence after resection of the tumor. However the survival time of malignant cystic tumors varied strongly. The curative resection of these tumors give patients the chance of long-term survival.

[Current therapy of bile duct cysts. II. Intrahepatic cysts (Caroli syndrome)]. / Aktuelle Therapie der Gallengangscysten. II. Intrahepatische Cysten (Caroli-Syndrom)

17 patients with a Caroli's syndrome are reviewed with emphasis on clinical features and late results (follow-up: 2-10 years). The group consists of 9 women and 8 men ranging in age from 17 to 80 years (mean of 42.6). 14 patients had a diffuse form, 5 of whom had periportal fibrosis with secondary biliary cirrhosis, which in 3 cases resulted in a portal hypertension with hepatic failure. In only 3 cases the dilatation was limited to the left lobe of the liver. 9 of the patients had previously undergone surgery in the form of cholecystectomy and choledocholithotomy elsewhere. The disease was complicated by lithiasis (14 intrahepatic, 9 extrahepatic). Curative treatment was only possible in the 3 patients with unilobar Caroli's syndrome (partial liver resection). In 5 patients we performed a cholecystectomy and choledocholithotomy combined in 2 cases with a transduodenal sphincterotomy. There was no operative death. Endoscopic treatment consisted in removal of stones and decompression of the biliary tree by sphincterotomy in 9 cases and endoscopic retrograde biliary drainage (endoprosthesis) in 5 cases. Excepting the 3 curative operated patients who are asymptomatic respectively 2, 4 and 5 years after surgery, the remaining cases had repeated bouts of acute pains accompanied by recurrent episodes of cholangitis. A late mortality of 23.5% (4 patients) is proof of the poor prognosis of this disease.