Preoperative risk assessment for postoperative pancreatic fistula (POPF): Image-based calculation of duct-to-parenchyma (D/P) ratio and an Alignment of Duct and Mucosa (ADAM) anastomosis may lead to a low POPF rate-results from 386 patients.

Background: Postoperative pancreatic fistula (POPF) is the most critical complication after pancreatoduodenectomy (PD). Preoperative identification of high-risk patients and optimal pancreatic reconstruction technique can be a way to reduce postoperative complications. Methods: A series of 386 patients underwent PD over a 10-year period (2009-2019). On routinely performed preoperative computed tomography (CT) images, the ventro-dorsal diameters of duct (D) and parenchyma (P) were measured in the cutting plane at the superior mesenteric vein. Then, the ratio of both values was calculated (D/P ratio) Double-layer pancreatojejunostomy with alignment of duct and mucosa (ADAM) by two monofilament threads (MFT) was performed in 359 patients and pancreatogastrostomy (PG) in 27 patients. The incidence of POPF was diagnosed according to the International Study Group for Pancreatic Fistula criteria. Results: The overall rate of POPF was 21% (n = 80), and the rate of clinically relevant type B/C fistulas 6.5% (n = 25). A D/P ratio of <0.2 was significantly associated with type B/C fistula (11%, p < 0.01). In low-risk patients (D/P ratio >0.2), type B/C fistula occurred only in 2%, and in high-risk patients (D/P ratio <0.2) in 9%. ADAM anastomosis was performed safely by two different surgeons. A PG anastomosis had double-digit POPF rates in all groups. Conclusion: Preoperative CT imaging with D/P measurement may predict the risk of POPF development. A cut off D/P ratio of <0.2 was significantly associated with clinical relevant POPF. ADAM anastomosis may be an option for pancreatojejunostomy. However, preoperative knowledge of the D/P ratio could guide decision-making for primary pancreatectomy when pancreatic reconstruction is critical.

Combined effects of moderate exercise and short-term fasting on markers of immune function in healthy human subjects.

This study aimed to investigate the effects of a short-term (36 h) fasting period combined with an acute bout of exercise on markers of immune function and inflammation in healthy human subjects. Fourteen moderately trained male subjects (aged 19-39 yr) participated in a 36-h fasting trial (FA-T), followed by an acute bout of moderate exercise (60% V̇o2max). After 1 wk, the same subjects, as their own control, participated in a nonfasting trial (NFA-T) in which they performed an exercise trial of the same duration and intensity. Blood samples were taken before, immediately after, and 1 h after each exercise bout and analyzed for several immunological and metabolic markers. At baseline, fasting subjects showed lower levels of T cell apoptosis, lymphocyte-proliferative responses, IL-6, monocyte chemoattractant protein-1 (MCP-1), insulin, and leptin (P < 0.05) as well as higher levels of neutrophil oxidative burst and thiobarbituric acid reactive substances (TBARS) than those in the NFA-T (P < 0.05). After the exercise protocol, fasted subjects revealed higher T cell apoptosis, neutrophil oxidative burst, TBARS, TNFα, and MCP-1 levels as well as lower levels of lymphocyte-proliferative response, IL-6, insulin, and leptin than those in the NFA-T (P < 0.05). Short-term fasting aggravates perturbations in markers of immune function, and inflammation was induced by an acute moderate-intensity exercise protocol.

Novel Dynamic Hepatic Magnetic Resonance Imaging Strategy Using Advanced Parallel Acquisition, Rhythmic Breath-Hold Technique, and Gadoxetate Disodium Enhancement.

OBJECTIVE: The aim of the study was to evaluate image quality of a dynamic hepatic magnetic resonance (MR) imaging strategy based on advanced parallel acquisition combined with rhythmic breath-hold and gadoxetate disodium enhancement. MATERIALS AND METHODS: Twenty-seven patients (21 male/6 female; mean age, 57.3 years) were enrolled in this institutional review board-approved study and underwent MR imaging at 3 T. The sequence (T1 3-dimensional gradient-recalled echo; acceleration factor, 4; reconstruction mode; controlled aliasing in parallel imaging resulting in higher acceleration factors; acquisition time, 10.4 seconds) was repeated at 8 fixed time points within the 3 minutes after contrast agent injection. Image quality was evaluated on a 5-point scale (1, excellent; 5, nondiagnostic). Dynamic sequences were classified according to perfusion phases and contrast characteristics. Artifacts and position of the liver in the z axis were recorded and analyzed. RESULTS: Overall image quality was found to be 1.44 (95% confidence interval, 1.18-1.71). Contrast was scored as excellent in 25 of 27 patients for central vessels and 22 of 27 patients for peripheral vessels. Adequate-quality arterial-phase images were obtained in all 27 patients. Double arterial and single arterial phases were acquired in 13 of 27 and 14 of 27 patients (n = 6 arterial dominant, n = 8 early arterial phases), respectively. In 1 (3.7%) of 27 patients, severe respiratory artifacts were seen during an early arterial phase. Artifacts were observed in 21 of 27 patients and rated as mild in 19 of these. Compromised quality was related to receiver coils (17 of 29), parallel imaging (6 of 29), breathing (3 of 29), and other causes (3 of 29). The position of the liver throughout the dynamic phases was highly constant, with a greatest mean shift of +2.9 mm throughout the first dynamic acquisition. CONCLUSIONS: Advanced parallel acquisition with rhythmic breath-hold and gadoxetate injection allows arterial phase imaging without breathing artifacts; a decelerated yet normal breathing pattern results in very robust breath-hold depth.

High impact running improves learning.

Regular physical exercise improves cognitive functions and lowers the risk for age-related cognitive decline. Since little is known about the nature and the timing of the underlying mechanisms, we probed whether exercise also has immediate beneficial effects on cognition. Learning performance was assessed directly after high impact anaerobic sprints, low impact aerobic running, or a period of rest in 27 healthy subjects in a randomized cross-over design. Dependent variables comprised learning speed as well as immediate (1 week) and long-term (>8 months) overall success in acquiring a novel vocabulary. Peripheral levels of brain-derived neurotrophic factor (BDNF) and catecholamines (dopamine, epinephrine, norepinephrine) were assessed prior to and after the interventions as well as after learning. We found that vocabulary learning was 20 percent faster after intense physical exercise as compared to the other two conditions. This condition also elicited the strongest increases in BDNF and catecholamine levels. More sustained BDNF levels during learning after intense exercise were related to better short-term learning success, whereas absolute dopamine and epinephrine levels were related to better intermediate (dopamine) and long-term (epinephrine) retentions of the novel vocabulary. Thus, BDNF and two of the catecholamines seem to be mediators by which physical exercise improves learning.

Endovascular gamma irradiation for the prevention restenosis after angioplasty of femoropopliteal de novo stenoses.

The purpose of this study was to investigate the effectiveness and detect side effects of centered, overlapped endovascular gamma irradiation after angioplasty of de novo femoropopliteal stenoses. Thirty patients (age 65.3+/-9.2 years) with arterial occlusive disease were prospectively enrolled to receive endovascular gamma irradiation (192-iridium, 14 Gy centered at 2 mm vessel wall) immediately after percutaneous transluminal angioplasty (PTA) of femoropopliteal stenoses. Irradiation overlapped dilatation by 1-2 cm at each end. Follow-up involved angiography after 12 months; duplex sonography; and interviews before and after PTA and at 1, 6, and 12 months follow-up. PTA and centered endovascular irradiation were performed successfully in all patients. Three thromboembolic complications occurred during irradiation. Angiographic and clinical follow-up was possible in 28 patients. The angiographic degree of stenosis was 73.8%+/-16.3% before and 3.6%+/-23.5% after PTA and was 3.5%+/-43.7% at the 1-year follow-up. Restenosis (>50%) of the target lesion developed in three patients (10.7%) and edge stenoses (>30%) in nine patients (32.1%). An aneurysm of the irradiated segment in one patient was treated by stenting. The rate of retreatment was 17.9%. The vessel diameter after endovascular gamma irradiation and PTA of femoropopliteal stenoses remained stable. Restenosis, induction of edge stenoses, and aneurysm were reasons for reinterventions.

Postcatheterization pseudoaneurysm: results of US-guided percutaneous thrombin injection in 240 patients.

PURPOSE: To prospectively evaluate ultrasonographically (US) guided percutaneous thrombin injection for treatment of femoral artery and brachial artery pseudoaneurysms. MATERIALS AND METHODS: The university institutional review board approved the study. Informed consent was obtained from all patients. Two hundred forty patients with postcatheterization femoral artery (n = 132) or brachial artery (n = 8) pseudoaneurysms were treated with US-guided bovine thrombin (1.000 IU/mL) injection. At diagnosis, 107 (44.6%) patients received anticoagulation therapy; 159 (66.2%), antiplatelet therapy; and 76 (31.7%), both therapies. Pseudoaneurysm size, length and width of pseudoaneurysm neck, thrombin dose, therapy outcome, and complications were documented. The peak blood flow in peripheral arteries was determined before and after thrombin injection. Follow-up duplex US was performed 12-24 hours, 5-7 days, and 21-25 days after treatment. A nonpaired t test was used to compare differences in age between the male and female patients. Two-way analysis of covariance was performed to analyze the influences of factors that may have been related to the amount of thrombin used. RESULTS: Mean pseudoaneurysm volume was 4.69 cm3 +/- 5.49 (standard deviation). Simple and complex pseudoaneurysms were treated in 165 and 75 patients, respectively. A total of 260 thrombin injections were performed: 1.04 injections per patient with a simple pseudoaneurysm and 1.17 injections per patient with a complex pseudoaneurysm. The mean injected thrombin dose was 425.31 IU +/- 341.75 for all pseudoaneurysms, 382.12 IU +/- 281.00 for simple pseudoaneurysms only, and 520.33 IU +/- 434.64 for complex pseudoaneurysms only. There was only a computational correlation between pseudoaneurysm size and thrombin dose (r2 = 0.07). The primary success rate was 93.8% overall, 95.8% for simple pseudoaneurysms, and 89% for complex pseudoaneurysms. The secondary success rate was 99.6% overall, 100% for simple pseudoaneurysms, and 99% for complex pseudoaneurysms. Early (at < or =24 hours) reperfusion occurred in one simple and five complex pseudoaneurysms. Four late reperfusions-two in simple and two in complex pseudoaneurysms-were detected at 1-week follow-up; no late reperfusions were detected at 3 weeks. Thromboembolic complications occurred in two patients and resolved spontaneously. One mild allergic reaction and no infections occurred. CONCLUSION: US-guided percutaneous thrombin injection enables successful, safe management of postcatheterization pseudoaneurysms.

Percutaneous treatment of a splenic artery pseudoaneurysm by thrombin injection.

Pseudoaneurysms in the visceral arteries are rare complications of pancreatitis. In the reported case, a 42-year-old man with a splenic pseudoaneurysm was successfully treated by computed tomography (CT)-guided direct thrombin injection into the pseudoaneurysm lumen. Selective catheterization of the splenic artery had proven technically impossible. During the procedure, contrast medium was injected via a pigtail catheter into the aorta for planning, correct positioning of the needle tip, and control imaging after injection. CT examinations 1 day, 3 weeks, and 6 months after treatment demonstrated complete occlusion shrinkage of the pseudoaneurysm, and the patient was symptom-free.

How thrombus model impacts the in vitro study of interventional thrombectomy procedures.

RATIONALE AND OBJECTIVES: Numerous experimental models are used to investigate the effectiveness of thrombectomy devices. We aimed to study the systematic effects of different in vitro thrombus models on the results of experimental thrombectomy and examined how thrombi formed in vitro and ex vivo differ. METHODS: Three variables involved in human in vitro thrombogenesis were investigated: spontaneous or thrombin-induced clotting, age (1 or 5 days old), and storage temperature (4 degrees C or 21 degrees C). The fibrin content of in vitro and fresh or old ex vivo thrombi was measured by histologic studies. Ten experiments were performed with each of 8 different in vitro thrombus types using (1) ultrasound thrombolysis, (2) Oasis thrombectomy, (3) Amplatz thrombectomy, and (4) Straub-Rotarex catheters. Thrombus weight was measured after standardized treatment. RESULTS: The fibrin content was markedly lower in all in vitro than in fresh and old ex vivo thrombi. In vitro thrombus type had no impact on the effectiveness of ultrasound thrombolysis and Amplatz thrombectomy. Thrombogenesis type affected Oasis and Straub-Rotarex catheter use. Storage temperature had a systematic impact on the outcome of Oasis thrombectomies. CONCLUSION: The fibrin content of in vitro thrombi differs substantially from that of fresh and old ex vivo human thrombi. Experimental conditions may systematically impact experimental evaluation of thrombectomy procedures. In vitro thrombi with thrombin-induced thrombogenesis should be favored for use in thrombectomy experiments.

Centered endovascular irradiation to prevent postangioplasty restenosis of arteriovenous fistula in hemodialysis patients; Results of a feasibility study.

PURPOSE: To report follow-up results of a prospective trial on centered endovascular gamma-irradiation (CEGI) after percutaneous transluminal angioplasty (PTA) for stenosis of arteriovenous fistula in hemodialysis patients. METHODS AND MATERIALS: Eight patients receiving PTA for recurrent (n = 4) or de novo arteriovenous fistula stenoses were treated with CEGI with iridium-192 (14 Gy). Angiography was performed after 6 and 12 months or if problems reoccurred during hemodialysis. Parameters of hemodialysis and duplex sonography were determined the day before and after PTA and after 1, 3, 6, 9, and 12 months. RESULTS: CEGI was performed successfully and without complications in seven patients. In six patients, restenosis occurred 6-52 weeks (mean 20.8 +/- 17.9 weeks) after PTA and required PTA. Parameters of hemodialysis and duplex sonography deteriorated during follow-up. CONCLUSIONS: Centered endovascular gamma-irradiation with iridium 192 immediately after PTA of fistula stenoses was a safe and feasible method but did not prevent restenosis.

De novo femoropopliteal stenoses: endovascular gamma irradiation following angioplasty--angiographic and clinical follow-up in a prospective randomized controlled trial.

PURPOSE: To assess and report the follow-up results of a randomized controlled trial on centered endovascular gamma irradiation performed after percutaneous transluminal angioplasty (PTA) for de novo femoropopliteal stenoses. MATERIALS AND METHODS: Thirty patients who underwent PTA for de novo femoropopliteal stenoses were randomly assigned to undergo 14-Gy centered endovascular irradiation (irradiation group, n = 15) or no irradiation (control group, n = 15). Intraarterial angiography was performed 6, 12, and 24 months after treatment; duplex ultrasonography (US), the day before and after PTA and 1, 3, 6, 9, 12, 18, and 24 months later. Treadmill tests and interviews were performed the day before PTA and 1, 3, 6, 9, 12, 18, and 24 months later. Results of angiography, duplex US, treadmill tests, and interviews were evaluated with the nonpaired t or the Fisher exact test. RESULTS: Baseline characteristics did not differ significantly between the two groups. Mean absolute individual changes in degree of stenosis, compared with the degrees of stenosis shortly after PTA, in the irradiation group versus in the control group were -10.6% +/- 22.3 versus 39.6% +/- 24.6 (P <.001) at 6 months, -2.0% +/- 34.2 versus 40.6% +/- 32.6 (P =.002) at 12 months, and 7.4% +/- 43.2 versus 37.7% +/- 34.5 (P =.043) at 24 months. The rates of target lesion restenosis at 6 (P =.006) and 12 (P =.042) months were significantly lower in the irradiation group. The numbers of target lesion re-treatments were similar between the groups, but target vessel re-treatments were more frequent in the irradiation group. There were no significant differences in interview or treadmill test results between the two groups at t test analysis. CONCLUSION: The degree of stenosis was significantly reduced 6, 12, and 24 months after angioplasty of de novo femoropopliteal stenoses in the patients who underwent endovascular irradiation.

Endovascular gamma-irradiation to prevent recurrent femoral in-stent restenosis. A case report.

We report about a patient with twice recurrence of femoral in-stent restenoses. Centered endoluminal gamma-irradiation with 192 iridium was performed immediately after the second stent recanalization. The irradiation dose was 14 Gy calculated at 2-mm depth of vessel wall. One-year follow-up demonstrates neither clinical nor angiographic evidence of restenosis.

Protocol of a thromboembolic stroke model in the rat: review of the experimental procedure and comparison of models.

RATIONALE AND OBJECTIVE: Different models to study the pathophysiology of cerebral ischemia and to evaluate therapeutic strategies exist. Described is the detailed procedure of a thromboembolic stroke model in the rat most closely resembling human embolic stroke and compare the model to other equivalent rodent models. MATERIALS AND METHODS: An evaluation of a new thromboembolic stroke model was performed on 35 male Wistar rats. After preparation of the carotid artery, a catheter was introduced into the external carotid artery. During injection of autologous, fibrin-rich emboli into the internal carotid artery the common carotid artery was temporarily occluded. Regional cerebral blood flow (rCBF) and lesion size were determined. RESULTS: Twelve fibrin-rich blood clots of 1.5 mm in length were necessary in order reliably to occlude the origin of the middle cerebral artery. A stable decrease of rCBF and lesion size was confirmed by autoradiography, diffusion, and perfusion MRI, TTC-staining, biochemical imaging, and histology. CONCLUSION: In this animal model, the situation of human cerebral ischemia is simulated closely. The model is suitable for investigations of the pathophysiology of stroke and facilitates studies on the effects of thrombolytic therapy.

Endovascular gamma irradiation of femoropopliteal de novo stenoses immediately after PTA: interim results of prospective randomized controlled trial.

PURPOSE: To report an interim analysis of whether centered endovascular irradiation with the iridium 192 ((192)Ir) source immediately after percutaneous transluminal angioplasty (PTA) of de novo femoropopliteal stenoses lowers the restenosis rate. MATERIALS AND METHODS: Thirty patients undergoing PTA to treat femoropopliteal stenoses were randomized for prophylaxis against restenosis with centered endovascular irradiation with a (192)Ir source (a dose of 14 Gy 2 mm deep to the vessel wall, irradiation group) or no irradiation (control group). Angiographic follow-up was available for 22 patients at 6 months (irradiation group, n = 10) and 12 patients at 12 months (irradiation group, n = 6). Duplex sonography, treadmill testing, and interviews were performed the day before and the day after PTA and after 1, 3, 6, 9, and 12 months. Results of angiography, duplex sonography, treadmill testing, and interviews were evaluated with a t test and multivariate analysis of variance (clinical characteristics, chi(2) test). RESULTS: Baseline characteristics were comparable in the two groups. Interim analysis of the 6-month follow-up data revealed a trend toward a significantly lower restenosis rate in the irradiation group. The change in the degree of stenosis compared with that after PTA was -14.7% +/- 20.8 (mean +/- SD) in the irradiation group versus 37.7% +/- 27.3 in the control group (P =.001) and became even more marked at 12 months (-9.5% +/- 34.5 vs 45.5% +/- 40.7 [P =.03], respectively). The follow-up results of treadmill testing and interviews showed a nonsignificant benefit for the irradiation group. One thromboembolic complication occurred during irradiation. No side effects were observed during follow-up. CONCLUSION: Endovascular irradiation with a centered (192)Ir source immediately after PTA of de novo femoropopliteal stenoses reduces the restenosis rate.

Aneurysmal re-rupture during selective cerebral angiography.

Two cases of aneurysmal re-rupture during intracranial angiography are presented. This event is accompanied by disastrous consequences with regard to the clinical condition of the patient, as is evident from the cases presented as well as from the literature. Acute alterations of intraluminal pressure as well as a time interval of less than 6 h seems to increase the risk of re-bleeding during angiography. The introduction of and the growing experience with CT and MR angiography may in the near future provide sufficient diagnostic information for surgical planning and thus help to overcome the risk of aneurysmal re-rupture during intra-arterial angiography.