Memory-friendly fixed-point iteration method for nonlinear surface mode oscillations of acoustically driven bubbles: from the perspective of high-performance GPU programming.

A fixed-point iteration technique is presented to handle the implicit nature of the governing equations of nonlinear surface mode oscillations of acoustically excited microbubbles. The model is adopted from the theoretical work of Shaw [1], where the dynamics of the mean bubble radius and the surface modes are bi-directionally coupled via nonlinear terms. The model comprises a set of second-order ordinary differential equations. It extends the classic Keller-Miksis equation and the linearized dynamical equations for each surface mode. Only the implicit parts (containing the second derivatives) are reevaluated during the iteration process. The performance of the technique is tested at various parameter combinations. The majority of the test cases needs only a single reevaluation to achieve 10-9 error. Although the arithmetic operation count is higher than the Gauss elimination, due to its memory-friendly matrix-free nature, it is a viable alternative for high-performance GPU computations of massive parameter studies.

The Impact of Diabetes Mellitus and Admission Hyperglycemia on Clinical Outcomes after Recanalization Therapies for Acute Ischemic Stroke: STAY ALIVE National Prospective Registry.

It was previously reported that diabetes mellitus (DM) and admission hyperglycemia (aHG) were associated with poor clinical outcomes in patients with acute ischemic stroke (AIS) who were treated with intravenous thrombolysis (IVT) or mechanical thrombectomy (MT). Our study aimed to assess the prognostic effect of DM and aHG (≥7.8 mmol/L) on clinical outcomes in patients treated with recanalization therapies (IVT and MT). Our multicentric study was based on data from the prospective STAY ALIVE stroke registry between November 2017 and January 2020. We compared the demographic data, clinical parameters and time metrics between recanalized DM and non-DM groups, and we analyzed the impact of DM and aHG on 90-day functional outcome, 90-day mortality, symptomatic intracranial hemorrhage (sICH), and successful recanalization. Statistical analyses were also performed in two subgroups: (1) patients treated with IVT alone and (2) patients treated with MT. Altogether, we included 695 patients from the three participating stroke centers in Hungary. Regarding the overall population, patients with diabetes were older (72 vs. 67 years, p < 0.001) and comorbidities were more frequent. There were significant differences in the 90-day good functional outcome (48.9% vs. 66.7%, p < 0.001), 90-day mortality (21.9% vs. 11.6%, p < 0.001) and the rate of symptomatic intracranial hemorrhaging (sICH) (7.8% vs. 2.2%, p < 0.001) between the groups. Diabetes and aHG were independently associated with a poor clinical outcome (OR 2.02, 95% CI 1.31−3.11, p = 0.001; OR 2.09, 95% CI 1.39−3.14, p < 0.001) and mortality at 3 months (OR 2.45, 95% CI 1.35−4.47, p = 0.003; OR 2.42, 95% CI 1.37−4.28, p = 0.002) and sICH (OR 4.32, 95% CI 1.54−12.09, p = 0.005; OR 4.61, 95% CI 1.58−13.39, p = 0.005) in the overall population. However, the presence of DM and aHG was not correlated with successful reperfusion (OR 0.39, 95% CI 0.09−1.67, p = 0.205; OR 0.42, 95% CI 0.09−1.97, p = 0.274) after MT. Our study revealed that diabetes and hyperglycemia on admission were correlated with poor clinical outcomes at 3 months in patients with acute stroke regardless of the recanalization method. In addition, the variables were also associated with sICH after recanalization therapies. However, successful recanalization was not associated with DM and aHG in patients who underwent MT.

Optimization of Large Vessel Occlusion Detection in Acute Ischemic Stroke Using Machine Learning Methods.

The early detection of large-vessel occlusion (LVO) strokes is increasingly important as these patients are potential candidates for endovascular therapy, the availability of which is limited. Prehospital LVO detection scales mainly contain symptom variables only; however, recent studies revealed that other types of variables could be useful as well. Our aim was to comprehensively assess the predictive ability of several clinical variables for LVO prediction and to develop an optimal combination of them using machine learning tools. We have retrospectively analysed data from a prospectively collected multi-centre stroke registry. Data on 41 variables were collected and divided into four groups (baseline vital parameters/demographic data, medical history, laboratory values, and symptoms). Following the univariate analysis, the LASSO method was used for feature selection to select an optimal combination of variables, and various machine learning methods (random forest (RF), logistic regression (LR), elastic net method (ENM), and simple neural network (SNN)) were applied to optimize the performance of the model. A total of 526 patients were included. Several neurological symptoms were more common and more severe in the group of LVO patients. Atrial fibrillation (AF) was more common, and serum white blood cell (WBC) counts were higher in the LVO group, while systolic blood pressure (SBP) was lower among LVO patients. Using the LASSO method, nine variables were selected for modelling (six symptom variables, AF, chronic heart failure, and WBC count). When applying machine learning methods and 10-fold cross validation using the selected variables, all models proved to have an AUC between 0.736 (RF) and 0.775 (LR), similar to the performance of National Institutes of Health Stroke Scale (AUC: 0.790). Our study highlights that, although certain neurological symptoms have the best ability to predict an LVO, other variables (such as AF and CHF in medical history and white blood cell counts) should also be included in multivariate models to optimize their efficiency.

Comparing Endovascular Treatment Methods in Acute Ischemic Stroke Due to Tandem Occlusion Focusing on Clinical Aspects.

INTRODUCTION: Acute ischemic strokes (AIS) due to tandem occlusion (TO) of intracranial anterior large vessel and concomitant extracranial internal carotid artery (EICA) are represent in 15-20% of all ischemic strokes. The endovascular treatment (EVT) strategy for those patients is still unclear. Although the intracranial mechanical thrombectomy (MT) is considered as a standard treatment approach, the EICA lesion stent necessity remains a matter of debate. We sought to assess the efficacy and safety of EVT in tandem lesions, particularly the EICA stenting management. METHODS: We retrospectively analyzed all patients with anterior circulation stroke associated with EICA lesion and receiving EVT in the three participated stroke centers between November 2017 and December 2020. Patients' data were collected from our prospective stroke registry (STAY ALIVE). Patients enrolled in our study were divided into two groups depending on whether acute carotid stenting (ACS) or balloon angioplasty only (BAO) technique was used. Our primary outcome was the 90-day functional outcome assessed by modified Rankin scale (mRS). Mortality at 90 days and symptomatic intracranial hemorrhage (sICH) were considered as secondary outcomes. RESULTS: A total of 101 patients (age: 67 ± 10 years, 38.6% female) were enrolled in our study, including 29 (28.3%) BAO cases, and 72 (71.3%) patients treated with ACS. Patients in the BAO group were slightly older (70 ± 9 years vs. 66 ± 10 years, p = 0.054), and had higher prevalence of comorbidities such as hypertension (100.0% vs. 59.4%, p < 0.001). There was no significant difference in favorable outcomes (51.7% vs. 54.4%, p = 0.808) between the groups. However, we observed a trend towards higher rates of sICH (8.3% vs. 3.4%, p = 0.382) and 90-day mortality (23.5% vs. 13.8%, p = 0.278) with significantly higher frequency of distal embolization (39.1% vs. 17.9%, p = 0.043) in patients with ACS. In the overall population age (p = 0.013), atrial fibrillation (AF) (p = 0.008), National Institutes of Health Stroke Scale (NIHSS) baseline (p = 0.029), and successful recanalization (p = 0.023) were associated with favorable outcome. CONCLUSION: Endovascular approach of EICA in addition to MT was safe and effective in tandem occlusion of anterior circulation. Furthermore, our results suggest that balloon angioplasty technique without acute stenting shows a comparable favorable outcome rate to ACS with moderately less hemorrhagic events and mortality rates.

Robotic Peripheral Vascular Intervention With Drug-Coated Balloons is Feasible and Reduces Operator Radiation Exposure: Results of the Robotic-Assisted Peripheral Intervention for Peripheral Artery Disease (RAPID) Study II.

BACKGROUND: A robotic-assisted platform (CorPath System; Corindus Vascular Robotics) is feasible for peripheral vascular intervention (PVI) for the treatment of femoropopliteal lesions. OBJECTIVES: This study was designed to determine the feasibility and safety of robotic PVI for treating femoropopliteal lesions with drug-coated balloon (DCB), and to evaluate the effect of robotic PVI on operator radiation exposure during robotic PVI. METHODS: This prospective, single-arm trial enrolled patients with symptomatic peripheral arterial disease affecting the femoropopliteal artery. The primary outcome measure was clinical success, defined as <50% residual stenosis and the absence of periprocedural device-related serious adverse events. Operator radiation exposure was compared between the robotic cockpit vs the tableside. RESULTS: This study enrolled 20 patients (age, 65.5 ± 9.9 years; 60% men), with the majority (75%) Rutherford category 3-4. A total of 24 lesions (lesion length, 49.8 ± 37.5 mm) were treated with DCB and 91.7% were located in the superficial femoral artery. Clinical success was 100% and provisional stenting was required in 1 lesion. Fluoroscopy time was 7.3 ± 3.3 minutes and operator radiation exposure was 1.9 ± 2.9 µSv, which was reduced by 96.9 ± 5.0% when compared with the table-side (control) dosimeter (P<.001). There were no adverse events associated with the use of the robotic system. CONCLUSIONS: These data demonstrate the safety and feasibility of using a robotic-assisted platform for treating femoropopliteal lesions with rapid-exchange interventional devices, and show 96.9% reduction in radiation exposure for the primary operator.

Feasibility and Safety of Robotic Peripheral Vascular Interventions: Results of the RAPID Trial.

OBJECTIVES: The goal of this study was to evaluate the feasibility and safety of a robotic-assisted platform (CorPath 200, Corindus Vascular Robotics, Waltham, Massachusetts) for treating peripheral artery disease. BACKGROUND: A robotic-assisted platform for percutaneous coronary intervention is available for treating coronary artery disease. METHODS: In this prospective single-arm trial, patients with symptomatic peripheral artery disease (Rutherford class 2 to 5) affecting the femoropoplital artery were enrolled. Endpoints evaluated were: 1) device technical success, defined as successful cannulation of the target vessel with the robotic system; 2) device safety, defined as absence of device related serious adverse event (hospitalization, prolonged hospitalization, life threatening, or resulted in death); and 3) clinical procedural success, defined as <50% residual stenosis without an unplanned switch to manual assistance or device-related serious adverse event in the periprocedural period. RESULTS: The study enrolled 20 subjects (65.5 ± 9.3 years of age; 70% male) with primarily Rutherford class 2 to 3 (90%) symptoms. A total of 29 lesions (lesion length: 33.1 ± 15.5 mm) were treated with the majority (89.7%) being located in the superficial femoral artery. Device technical success, safety and clinical procedural success were all 100% with provisional stenting required in 34.5% of lesions. Fluoroscopy time (7.1 ± 3.2 min) and contrast use (73.3 ± 9.2 ml) compared favorably with studies in similar patient cohorts. There were no adverse events associated with the use of the robotic system. CONCLUSIONS: These data demonstrate the feasibility and safety of using a robotic-assisted platform for performing peripheral arterial revascularization.

Gadolinium-free MR in coarctation-can contrast-enhanced MR angiography be replaced?

OBJECTIVE: To determine the difference in vessel measurements, signal-to-noise ratio (SNR), and voxel size between contrast-enhanced and noncontrast magnetic resonance techniques in patients with coarctation of the aorta (CoA). MATERIALS AND METHODS: In 39 patients, vessel size, SNR, and voxel size were compared in cine magnetic resonance imaging (MRI), gadolinium-free magnetic resonance angiography (Gd-free MRA), and contrast-enhanced MRA (ce-MRA). RESULTS: There was no significant difference in measurement and SNR, but there was a significant difference in voxel size (P<.001). CONCLUSIONS: Our results show that, in CoA patients, monitoring of vessel size using cine MRI and Gd-free MRA is equivalent to ce-MRA while being less invasive.

European Guidelines for AP/PA chest X-rays: routinely satisfiable in a paediatric radiology division?

OBJECTIVES: Accurate collimation helps to reduce unnecessary irradiation and improves radiographic image quality, which is especially important in the radiosensitive paediatric population. For AP/PA chest radiographs in children, a minimal field size (MinFS) from "just above the lung apices" to "T12/L1" with age-dependent tolerance is suggested by the 1996 European Commission (EC) guidelines, which were examined qualitatively and quantitatively at a paediatric radiology division. METHODS: Five hundred ninety-eight unprocessed chest X-rays (45% boys, 55% girls; mean age 3.9 years, range 0-18 years) were analysed with a self-developed tool. Qualitative standards were assessed based on the EC guidelines, as well as the overexposed field size and needlessly irradiated tissue compared to the MinFS. RESULTS: While qualitative guideline recommendations were satisfied, mean overexposure of +45.1 ± 18.9% (range +10.2% to +107.9%) and tissue overexposure of +33.3 ± 13.3% were found. Only 4% (26/598) of the examined X-rays completely fulfilled the EC guidelines. CONCLUSIONS: This study presents a new chest radiography quality control tool which allows assessment of field sizes, distances, overexposures and quality parameters based on the EC guidelines. Utilising this tool, we detected inadequate field sizes, inspiration depths, and patient positioning. Furthermore, some debatable EC guideline aspects were revealed. KEY POINTS: • European Guidelines on X-ray quality recommend exposed field sizes for common examinations. • The major failing in paediatric radiographic imaging techniques is inappropriate field size. • Optimal handling of radiographic units can reduce radiation exposure to paediatric patients. • Constant quality control helps ensure optimal chest radiographic image acquisition in children.

Is Embolization an Effective Treatment for Recurrent Hemorrhage After Hip or Knee Arthroplasty?

BACKGROUND: Spontaneous recurrent hemorrhage after arthroplasty of the hip or knee is a rare condition. In patients who do not have coagulopathy, the likeliest etiology for hemarthrosis is hypertrophic vascular synovium. Treatments include arthroscopic or open synovectomy, or angiography with embolization; however, because the condition is rare, seldom reported, and debilitating, small case series characterizing the efficacy of any approach are important to allow a collective experience with this condition to emerge. QUESTIONS/PURPOSES: We attempted to (1) determine whether angiography with embolization can prevent recurrent hemarthrosis after hip or knee arthroplasty in a small series of patients with or without coagulopathy, and (2) evaluate complications associated with this intervention. METHODS: Between 2005 and 2014, seven patients presented with spontaneous, recurrent hemarthroses. One patient had polycythemia vera and factor XIII deficiency as underlying illnesses. All patients were treated with selective transarterial embolization, and all had followup at a minimum of 12 months (range, 12-102 months; median, 74 months). Other treatments during this time included hematoma removals and flap operations in one patient, and indications for transarterial embolization included recurrent hemarthrosis. The patients included six men and one woman with a median age of 72 years (range, 61-78 years). Five patients underwent one or more reoperations before transarterial embolization. A diagnostic workup for coagulopathy was performed in all patients; one patient was identified to have polycythemia ruba vera and factor XIII deficiency, however the patient still was treated with transarterial embolization because it was perceived to be the least invasive of available options. No other patients had a diagnosis of coagulopathy. Angiography showed hypervascularity in all patients and a contrast agent showed extravasation in two. Selective transarterial embolization of branches of the internal iliac artery, common femoral artery, deep femoral artery, or the popliteal artery was performed with polyvinyl alcohol particles, microspheres, and/or coils. Patients were followed clinically during 12 to 102 months (median, 74 months) to determine whether the hemorrhages recurred. RESULTS: Technical success was achieved in all patients. No procedure-related complications were reported. On followup, recurrent hemorrhage was reported in one patient who had a diagnosis of coagulopathy before the procedure. He underwent three reinterventions and five reoperations. Three months after initial embolization, a flap procedure was performed. CONCLUSIONS: In a small series of patients with a minimum followup of 1 year, we found selective transarterial embolization to be effective in patients without underlying coagulopathy in preventing recurrences of spontaneous recurrent hematoma or hemarthrosis of the hip and the knee. This condition is rare, therefore comparative trials are unlikely to be done. Because transarterial embolization is relatively low risk and generally well tolerated, we consider it to be a reasonable approach for consideration with other options such as arthroscopic or open synovectomy and revision arthroplasty. LEVEL OF EVIDENCE: Level IV, therapeutic study.

Co-occurrence of carbohydrate malabsorption and primary epiploic appendagitis.

Unspecific abdominal complaints including bloating and irregular bowel movements may be caused by carbohydrate malabsorption syndromes, e.g., lactose and fructose malabsorption. These symptoms were investigated with hydrogen (H2) breath tests and correlated to carbohydrate malabsorption. During performing these H2-breath tests the patient presented with an acute, localized, non-migratory pain in the left lower abdominal quadrant. Primary epiploic appendagitis is a rare cause of abdominal acute or subacute complaints and diagnosis of primary epiploic appendagitis (PEA) is made when computed tomography reveals a characteristic lesion. We report on a patient with co-occurrence of lactose and fructose malabsorption, which was treated successfully with a diet free of culprit carbohydrates, with PEA recovering without medication or surgical treatment within few days. Since the abdominal unspecific symptoms had been present for months, they appeared not to be correlated to the acute localized abdominal pain, therefore we speculate on a random co-occurrence of combined carbohydrate malabsorption and PEA.

The eternal tale of dialysis access vessels and restenosis: are drug-eluting balloons the solution?

In dialysis access fistulas and grafts, percutaneous transluminal angioplasty (PTA) is frequently followed by restenosis development, which results in repeated periodical re-interventions. The technique of drug-eluting balloon (DEB) angioplasty has shown promising results in the treatment of femoropopliteal arteriosclerotic lesions. In contrast to arteriosclerotic arteries, dialysis access vessels host unfavorable hemodynamics due to the direct conduction of high-pressure fluid into a low-pressure system. Hence, the beneficial effect of DEB angioplasty may be limited in this system. However, a first prospective randomized trial on 40 patients with arteriovenous fistula or graft stenoses exhibited a significantly higher 6-month primary patency of the treated lesions after DEB angioplasty than after uncoated balloon angioplasty. Despite such a positive reference, general recommendations regarding the value of DEBs in dialysis access vessels cannot be considered as serious unless large randomized controlled trials have been performed.

The impact of iterative reconstruction on image quality and radiation dose in thoracic and abdominal CT.

PURPOSE: To compare the image quality and radiation dose between iterative reconstruction (IR) and standard filtered back projection (FBP) in CT of the chest and abdomen. MATERIALS AND METHODS: Thoracic CT was performed in 50 patients (38 male, 12 female; mean age, 51 ± 23 yrs; range, 7-85 yrs) and abdominal CT was performed in 50 patients (36 male, 14 female; mean age, 62 ± 13 yrs; range, 20-85 yrs), using IR as well as FBP for image reconstruction. Image noise was quantitatively assessed measuring standard deviation of Hounsfield Units (HU) in defined regions of interest in subcutaneous tissue. Scan length and Computed Tomography Dose Index (CTDI) were documented. Scan length, image noise, and CTDI of both reconstruction techniques were compared by using paired tests according to the nature of variables (McNemar test or Student t test). Overall subjective image quality and subjective image noise were compared. RESULTS: There was no significant difference between the protocols in terms of mean scan length (p>0.05). Image noise was statistically significantly higher with IR, although the difference was clinically insignificant (13.3 ± 3.0 HU and 13.6 ± 3.0 HU for thoracic CT and 11.5 ± 3.1 HU and 11.7 ± 3.0 HU for abdominal CT, p<0.05). There was no significant difference in overall subjective image quality and subjective image noise. The radiation dose was significantly lower with IR. Volume-weighted CTDI decreased by 64% (6.2 ± 2.5 mGy versus 17.1 ± 9.5 mGy, p<0.001) for thoracic CT and by 58% (7.8 ± 4.6 mGy versus 18.5 ± 8.6 mGy, p<0.001) for abdominal CT. CONCLUSIONS: Our study shows that in thoracic and abdominal CT with IR, there is no clinically significant impact on image quality, yet a significant radiation dose reduction compared to FBP.

Placement of hemoparin-coated stents in the iliac arteries: early experience and midterm results in 28 patients.

PURPOSE: Aim was to determine immediate results and mid-term outcome of the hemoparin-coated (HC) stainless-steel stent (camouflage coating) in the treatment of occlusive lesions of the iliac arteries. MATERIALS AND METHODS: Twenty-eight patients were prospectively treated with the use of a HC stent between January 2007 and March 2010. Clinical examination and color-doppler ultrasound were performed at 1, 3, 6 and 12 months, CT angiography (CTA) or MR angiography (MRA) at 12 months. Indication for treatment was a high-grade stenosis of the common iliac and/or external iliac artery. RESULTS: Successful placement was achieved in all patients. Significant decrease in translesional pressure gradient (>10 mm Hg) was measured in 27 patients (96%). In one patient, proximal dissection occurred without flow limitation. A minor complication (small access site hematoma) occurred in one patient (4%). Two patients (7%) were lost to follow-up. After 12 months, stent patency in CTA, MRA and ultrasound was 100%. 20 patients (77%) experienced an initial improvement of at least one clinical stage. In one patient (4%), mild intimal hyperplasia without significant stenosis was observed. In three patients (12%), proximal or distal stenosis occurred. A non-significant increase of mean ankle-brachial index (ABI) after treatment was measured (0.85 ± 0.27 vs. 0.75 ± 0.22, respectively; p=0.328). CONCLUSIONS: The use of HC stents in patients with iliac artery occlusive disease may lead to a lower rate of intimal hyperplasia and thus to increased patency rates even in heavily calcified vessels. However, large-scale prospective trials have to be performed to evaluate the long-term patency rates of the HC coated stents.

Large, segmental, circular vascular malformation of the small intestine (in a female toddler with hematochezia): unusual presentation in a child.

BACKGROUND: Failure to thrive and hematochezia in children may be alarm signs warranting endoscopy. In contrast, vascular malformations of the small intestine are uncommon in this age group. We report on a female toddler in whom various imaging techniques revealed an unusually large segmental vascular malformation of the ileum as the cause of the child's main clinical symptoms. CASE PRESENTATION: A 19 months old girl presented with severe anemia (Hb 3 mmol/l), failure to thrive and chronic diarrhea. Diagnostics for intestinal blood loss and pathogens were negative. The child had duodenoscopy, also for histological diagnosis of celiac disease, with negative results. A dietary protocol was suggestive for inadequate iron intake and she was supplemented. After symptomless four-months the child presented again, now with mild abdominal pain and, for the first time, hematochezia. An orienting abdominal ultrasound (US) study showed a suspicious tumorous bowel condition. A subsequent detailed abdominal US supplemented by a saline enema during investigation (i.e., "hydrocolon", to improve outlining of the formation's localization) revealed a large circumferential cystiform vascular mass of the ileum causing segmental ileal obstruction.Complementing preoperative abdominal hydro-MRI, planned based on the findings of the US study, confirmed the suspected vascular malformation of the ileum and exquisitely outlined the extent, location and anatomy.The patient was successfully operated laparoscopically, the affected ileum segment with the mass was completely removed as proven by histology, and the child recovered well. CONCLUSIONS: The huge segmental vascular malformation of the distal ileum described here is an extreme rarity in young children. Although the reported child's presenting symptoms malabsorption and malnutrition could have been responsible for its severe anemia, this was obviously caused by blood losses from the ileal vascular malformation. It was due to incipient abdominal pain rather than hematochezia that abdominal US was performed and proved crucial for correctly diagnosing this rare malformation. Even in this extensive case detailed imaging work-up including adapted MRI added all information necessary for minimal invasive laparoscopic en bloc resection.

Gd-EOB-DTPA enhanced MRI of the liver: correlation of relative hepatic enhancement, relative renal enhancement, and liver to kidneys enhancement ratio with serum hepatic enzyme levels and eGFR.

OBJECTIVES: To assess the correlation of relative hepatic enhancement (RHE), relative renal enhancement (RRE) and liver to kidneys enhancement ratio (LKR) with serum hepatic enzyme levels and eGFR in Gd-EOB-DTPA enhanced MRI of the liver and to assess threshold levels for predicting enhancement of the liver parenchyma. METHODS: Data of 75 patients who underwent Gd-EOB-DTPA enhanced MRI of the liver were collected. Images were obtained before contrast injection, during the early arterial phase, late arterial phase, venous phase, delayed phase, and hepatobiliary phase which was 20 min after Gd-EOB-DTPA administration. Signal intensity of the liver and the kidneys in all phases was defined using region-of-interest measurements for relative enhancement calculation. Serum hepatic enzyme levels and eGFR were available in all patients. Spearman correlation test was used to test the correlation of RHE, RRE and LKR with serum hepatic enzyme levels and eGFR. RESULTS: In the hepatobiliary phase all serum hepatic enzymes were significantly correlated with RHE; total bilirubin (TBIL) and cholin esterase (CHE) showed strongest correlations. TBIL and CHE were significantly correlated with RRE in the arterial phases. TBIL and CHE were significantly correlated with LKR in the arterial phase and hepatobiliary phase. eGFR showed no correlation. CONCLUSIONS: In Gd-EOB-DTPA enhanced MRI, TBIL and CHE levels may predict RHE, RRE and LKR.

Secondary aortic dissection after endoluminal treatment of an intramural hematoma of the thoracoabdominal aorta: endovascular extension with two stent grafts and scarce distal landing.

Secondary dissection in the descending aorta after endovascular therapy may demand subsequent interventional procedures. This can set a particularly significant challenge for the endovascular specialist. When implanting an aortic prosthesis, a sufficient contact between the covered segment and the healthy vessel wall is advisable. However, our case shows that, in individual cases, it is indeed efficient to place an aortic stent graft on top of the distal end of the dissection. This is proven by a three-year follow-up CT-angiography.

Renal transplant from very old donors: how far can we go?

BACKGROUND: The organ shortage has led many transplant centers to accept kidneys from old, suboptimal deceased donors, and make increasing use of old-for-old allocation systems. We report the experience of an Italian transplant center in the utilization of "ultra-old" (>75 years old) donors. METHODS: Sixty grafts from donors aged 75 years or older (mean age 79.1 years, range 75-90 years) were used for 38 patients: 16 as single and 22 as double transplants. RESULTS: The actuarial graft survival rate was 73.7% for year 1, 69.8% for year 2, and 64.0% for year 3. The patient survival rate was 81.2% and remained stable for years 1, 2, and 3. The delayed graft function rate was 57.9%. Acute rejection and chronic allograft nephropathy rates were comparable with our other expanded criteria donors. The majority of the patients had stable creatinine levels, between 2 and 3 mg/mL after the second month, with sufficient creatinine clearance. CONCLUSIONS: Our results seems encouraging with patient and graft survival rates, complication rates, and renal function parameters being slightly worse than in expanded criteria donors, but still generally acceptable. The use of old kidneys in old recipients, bearing in mind their usual life expectancy, gives them a properly functioning kidney and improved quality of life.

Activation of fibrinolysis in the pericardial cavity after cardiopulmonary bypass.

Aprotinin is frequently administered systemically in patients undergoing cardiopulmonary bypass to preserve platelet function and ameliorate excessive activation of fibrinolysis. More recently, aprotinin topically applied in the pericardial cavity was also found to improve postoperative blood loss. However, platelet activation was not reduced locally during surgery. Hence, we investigated in the present prospective, in a randomized double-blind trial, the intra- and early postoperative state of systemic and local fibrinolytic activity, and whether topically administered aprotinin acts as an antifibrinolytic and therefore improves local hemostasis. Patients undergoing elective coronary artery bypass grafting were divided in two groups containing 22 patients each. Both, group I and II patients received high-dose aprotinin (6.0 x 10(6) kallikrein inhibitor units (KIU)) systemically. Before resuming extracorporeal circulation (ECC), either 1.0 x 10(6) KIU aprotinin (group I) or vehicle solution (group II) was applied into the pericardial cavity. Plasminogen, 2 alpha(2)-antiplasmin, plasmin-alpha(2)-antiplasmin complex, plasminogen-activator-inhibitor type-1 and D-dimers were measured in the pericardial cavity and systemic circulation immediately before resuming extracorporeal circulation (ECC), and at 1 h and 4 h postoperatively. The local fibrinolytic activity was found to significantly exceed that measured in the systemic circulation over time, whether ot not they received aprotinin into the thoracic wound surface. Furthermore, evidence was provided that topically applied aprotinin reduces not only the local fibrinolytic activity but also the postoperative blood loss significantly by 33% which demonstrates the clinical relevance. The local activation of fibrinolysis seems to play an important role in blood loss after cardiopulmonary bypass. Therefore in fibrinolysis and blood coagulation the surgeon should not only consider what happens in the systemic circulation but also on a local level.