Nurse Preceptors' Experiences of an Online Strength-Based Nursing Course in Clinical Teaching.

Background: Online educational programs for nurse preceptors have been created based on various theoretical frameworks; however, no programs using a Strengths-Based Nursing (SBN) approach could be located. Purpose: This qualitative descriptive study explored the nurse preceptors' experiences in using a SBN approach to provide clinical teaching to nursing students after completing an online SBN clinical teaching course. Methods: Semi-structured interviews were conducted with six nurses. Data was thematically analyzed. Findings: Although their levels of familiarity with SBN varied, all preceptors acknowledged that using a SBN approach in clinical teaching benefits both students and educators. They reported that it empowered students and that it allowed them to discover their strengths. Getting to know their students helped the preceptors provide tailored learning experiences and feedback. Using the SBN approach simultaneously enhanced the preceptors' self-confidence and created opportunities for shared learning. Conclusion: Using a strengths' approach offers nurse preceptors a powerful tool to facilitate student learning and skills development in clinical practice.

Endovascular renal sympathetic denervation to improve heart failure with reduced ejection fraction: the IMPROVE-HF-I study.

INTRODUCTION: The aim of the present study was to assess the safety and efficacy of renal sympathetic denervation (RDN) in patients with heart failure with reduced ejection fraction (HFrEF). METHODS: We randomly assigned 50 patients with a left ventricular ejection fraction (LVEF) ≤ 35% and NYHA class ≥ II, in a 1:1 ratio, to either RDN and optimal medical therapy (OMT) or OMT alone. The primary safety endpoint was the occurrence of a combined endpoint of cardiovascular death, rehospitalisation for heart failure, and acute kidney injury at 6 months. The primary efficacy endpoint was the change in iodine-123 meta-iodobenzylguanidine (123I­MIBG) heart-to-mediastinum ratio (HMR) at 6 months. RESULTS: Mean age was 60 ± 9 years, 86% was male and mean LVEF was 33 ± 8%. At 6 months, the primary safety endpoint occurred in 8.3% vs 8.0% in the RDN and OMT groups, respectively (p = 0.97). At 6 months, the mean change in late HMR was -0.02 (95% CI: -0.08 to 0.12) in the RDN group, versus -0.02 (95% CI: -0.09 to 0.12) in the OMT group (p = 0.95) whereas the mean change in washout rate was 2.34 (95% CI: -6.35 to 1.67) in the RDN group versus -2.59 (95% CI: -1.61 to 6.79) in the OMT group (p-value 0.09). CONCLUSION: RDN with the Vessix system in patients with HFrEF was safe, but did not result in significant changes in cardiac sympathetic nerve activity at 6 months as measured using 123I­MIBG.

Listing criteria for heart transplantation in the Netherlands.

The updated listing criteria for heart transplantation are presented on behalf of the three heart transplant centres in the Netherlands. Given the shortage of donor hearts, selection of those patients who may expect to have the greatest benefit from a scarce societal resource in terms of life expectancy and quality of life is inevitable. The indication for heart transplantation includes end-stage heart disease not remediable by more conservative measures, accompanied by severe physical limitation while on optimal medical therapy, including ICD/CRT­D. Assessment of this condition requires cardiopulmonary stress testing, prognostic stratification and invasive haemodynamic measurements. Timely referral to a tertiary centre is essential for an optimal outcome. Chronic mechanical circulatory support is being used more and more as an alternative to heart transplantation and to bridge the progressively longer waiting time for heart transplantation and, thus, has become an important treatment option for patients with advanced heart failure.

Sex-specific temporal evolution of circulating biomarkers in patients with chronic heart failure with reduced ejection fraction.

BACKGROUND: We aimed to assess differences in clinical characteristics, prognosis, and the temporal evolution of circulating biomarkers in male and female patients with HFrEF. METHODS: We included 250 patients (66 women) with chronic heart failure (CHF) between 2011 and 2013 and performed trimonthly blood sampling during a median follow-up of 2.2 years [median (IQR) of 8 (5-10) urine and 9 (5-10) plasma samples per patient]. After completion of follow-up we measured 8 biomarkers. The primary endpoint (PE) was the composite of cardiac death, cardiac transplantation, left ventricular assist device implantation, and hospitalization due to acute or worsened CHF. Joint models were used to determine whether there were differences in the temporal patterns of the biomarkers between men and women as the PE approached. RESULTS: A total of 66 patients reached the PE of which 52 (78.8%) were male and 14 (21.2%) were female. The temporal patterns of all studied biomarkers were associated with the PE, and overall showed disadvantageous changes as the PE approached. For NT-proBNP, HsTnT, and CRP, women showed higher levels over the entire follow-up duration and concomitant numerically higher hazard ratios [NT-proBNP: women: HR(95%CI) 7.57 (3.17-21.93), men: HR(95%CI) 3.14 (2.09-4.79), p for interaction = 0.104, HsTnT: women: HR(95%CI) 6.38 (2.18-22.46), men: HR(95%CI) 4.91 (2.58-9.39), p for interaction = 0.704, CRP: women: HR(95%CI) 7.48 (3.43-19.53), men: HR(95%CI) 3.29 [2.27-5.44], p for interaction = 0.106). In contrast, temporal patterns of glomerular and tubular renal markers showed similar associations with the PE in men and women. CONCLUSION: Although interaction terms are not statistically significant, the associations of temporal patterns of NT-proBNP, HsTnT, and CRP appear more outspoken in women than in men with HFrEF, whereas associations seem similar for temporal patterns of creatinine, eGFR, Cystatin C, KIM-1 and NAG. Larger studies are needed to confirm these potential sex differences.

In search of an efficient strategy to monitor disease status of chronic heart failure outpatients: added value of blood biomarkers to clinical assessment.

INTRODUCTION: Blood biomarkers have the potential to monitor the severity of chronic heart failure (CHF). Studies correlating repeated measurements of blood biomarkers with repeatedly assessed New York Heart Association (NYHA) class over a prolonged follow-up period, and concomitantly investigating their associations with clinical endpoints, have not yet been performed. METHODS: Between 2011-2013, 263 CHF patients were included. At inclusion and subsequently every 3 months, we measured N­terminal pro-B-type natriuretic (NT-proBNP), high-sensitivity troponin T (Hs-TnT) and C­reactive protein (CRP), and assessed NYHA class. The primary endpoint comprised heart failure hospitalisation, cardiovascular mortality, cardiac transplantation or left ventricular assist device implantation. Time-dependent Cox models were used. RESULTS: Mean age was 67 ± 13 years, 72% were men and 27% were in NYHA class III-IV. We obtained 886 repeated measures (median 3 [IQR 2-5] per patient). The primary endpoint was reached in 41 patients during a median follow-up of 1.0 [0.6-1.4] year. Repeatedly measured NT-proBNP and Hs-TnT were significantly associated with repeatedly assessed NYHA class, whereas CRP was not (NT-proBNP: ß [95% CI]: 1.56 [1.17-2.06]ln(ng/l) increase per point increase in NYHA class, p = 0.002; HsTNT: ß [95% CI]: 1.58 [1.21-2.07]). Serially measured NT-proBNP (HR [95% CI]:2.86 [1.73-4.73]), CRP (1.69 [1.21-2.34]) and NYHA class (2.33 [1.51-3.62]) were positively and independently associated with the primary endpoint, whereas Hs-TnT lost statistical significance after multivariable adjustment. A model containing serially measured NYHA class and NT-proBNP displayed a C-index of 0.84, while serially measured NYHA class and CRP showed a C-index of 0.82. CONCLUSION: Temporal NT-proBNP, CRP and NYHA class patterns are independently associated with adverse clinical outcome. Serially measured NT-proBNP and NYHA class are best suited for monitoring CHF outpatients.

Cardiac allograft vasculopathy in Dutch heart transplant recipients.

BACKGROUND: Cardiac allograft vasculopathy (CAV) is a multifactorial disease and a major cause of graft failure after heart transplantation. However, the impact of CAV may vary according to the definition and the regional differences in transplantation settings. OBJECTIVES: We sought to assess CAV prevalence, predictors and prognosis in Dutch heart transplant recipients based on coronary angiography, following the 2010 standard nomenclature of the International Society for Heart and Lung Transplantation. METHODS: Patients ≥18 years who underwent heart transplantation at our centre with at least one coronary angiography during follow-up were included in the analysis. Clinical variables were collected prospectively. RESULTS: Among 495 analysed recipients, there were 238 (48 %) with CAV. The prevalence of CAV was 18, 47 and 70 % at 4, 12 and 20 years, respectively. In the multivariable proportional hazards regression analysis, only male donor gender and increasing donor age were significantly associated with the risk of CAV. The long-term prognosis of the patients with CAV at fourth-year angiography was significantly worse as compared with that of CAV-free patients, independently of the severity of CAV (p < 0.001). CONCLUSION: The prevalence of CAV increased gradually over time, with a similar trend as in other registries. Post-transplant survival is decreased in patients with any degree of early CAV, indicating that management strategies should start with donor selection and preventive measures immediately after transplantation.

Fatigue of Metallic Stents: From Clinical Evidence to Computational Analysis.

The great success of stents in treating cardiovascular disease is actually undermined by their long-term fatigue failure. The high variability of stent failure incidence suggests that it is due to several correlated aspects, such as loading conditions, material properties, component design, surgical procedure, and patient functional anatomy. Numerical and experimental non-clinical assessments are included in the recommendations and requirements of several regulatory bodies and they are thus exploited in the analysis of stent fatigue performance. Optimization-based simulation methodologies have been developed as well, to improve the fatigue endurance of novel designs. This paper presents a review on the fatigue issue in metallic stents, starting from a description of clinical evidence about stent fracture up to the analysis of computational approaches available from the literature. The reported discussion on both the experimental and numerical framework aims at providing a general insight into stent lifetime prediction as well as at understanding the factors which affect stent fatigue performance for the design of novel components.

Haemolysis as a first sign of thromboembolic event and acute pump thrombosis in patients with the continuous-flow left ventricular assist device HeartMate II.

BACKGROUND: Despite advances in pump technology, thromboembolic events/acute pump thrombosis remain potentially life-threatening complications in patients with continuous-flow left ventricular assist devices (CF-LVAD). We sought to determine early signs of thromboembolic event/pump thrombosis in patients with CF-LVAD, which could lead to earlier intervention. METHODS: We analysed all HeartMate II recipients (n = 40) in our centre between December 2006 and July 2013. Thromboembolic event/pump thrombosis was defined as a transient ischaemic attack (TIA), ischaemic cerebrovascular accident (CVA), or pump thrombosis. RESULTS: During median LVAD support of 336 days [IQR: 182-808], 8 (20 %) patients developed a thromboembolic event/pump thrombosis (six TIA/CVA, two pump thromboses). At the time of the thromboembolic event/pump thrombosis, significantly higher pump power was seen compared with the no-thrombosis group (8.2 ± 3.0 vs. 6.4 ± 1.4 W, p = 0.02), as well as a trend towards a lower pulse index (4.1 ± 1.5 vs. 5.0 ± 1.0, p = 0.05) and a trend towards higher pump flow (5.7 ± 1.0 vs. 4.9 ± 1.9 L m, p = 0.06). The thrombosis group had a more than fourfold higher lactate dehydrogenase (LDH) median 1548 [IQR: 754-2379] vs. 363 [IQR: 325-443] U/L, p = 0.0001). Bacterial (n = 4) or viral (n = 1) infection was present in 5 out of 8 patients. LDH > 735 U/L predicted thromboembolic events/pump thrombosis with a positive predictive value of 88 %. CONCLUSIONS: In patients with a CF-LVAD (HeartMate II), thromboembolic events and/or pump thrombosis are associated with symptoms and signs of acute haemolysis as manifested by a high LDH, elevated pump power and decreased pulse index, especially in the context of an infection.

The effect of levodopa-carbidopa intestinal gel infusion long-term therapy on motor complications in advanced Parkinson's disease: a multicenter Romanian experience.

Chronic treatment with oral levodopa is associated with an increased frequency of motor complications in the late stages of Parkinson's disease (PD). Continuous administration of levodopa-carbidopa intestinal gel (LCIG-Duodopa(®), Abbott Laboratories), which has been available in Romania since 2009, represents an option for treating patients with advanced PD. Our primary objective was to report changes in motor complications after initiation of LCIG therapy. The secondary objectives were as follows: to determine the impact of LCIG therapy on the daily levodopa dose variation before/and after LCIG, to collect patient self-assessments of quality of life (QoL), and to study the overall tolerability and safety of LCIG administration. A retrospective analysis (2009-2013) of LCIG therapy and the experience in nine neurology centers in Romania was performed. The impact of LCIG therapy was evaluated by analyzing changes in motor fluctuations, dyskinesia and the patients' QoL after initiating therapy. The safety of LCIG therapy was estimated by noting agent-related adverse events (AEs) and medical device-related AEs. In the 113 patients included, we observed a significant improvement in PD symptoms after initiation of LCIG therapy. The "on" period increased, with a mean value of 6.14 h, and the dyskinesia period was reduced, with a mean value of 29.4 %. The quantified non-motor symptoms subsided. The patients exhibited significant improvements in QoL scores. There were few AEs and few cases of LCIG therapy discontinuation. LCIG is an important and available therapeutic option for managing patients with advanced PD.

Diabetes mellitus and renal involvement in chronic viral liver disease.

HYPOTHESIS: Chronic viral liver disease is often associated with other conditions. Diabetes mellitus (DM) is frequently reported in this context and may play a role in the progression of the liver disease to hepatocellular carcinoma (HCC). Renal disease is also an important extrahepatic manifestation of hepatitis viral infection and its presence is associated with poor prognosis and management issues. OBJECTIVES: Our study had multiple purposes: to determine the frequency of the association between chronic viral liver disease and diabetes mellitus, evaluate the potential of diabetes mellitus as a risk factor for HCC and assess an eventual renal involvement. METHODS AND RESULTS: We included in our study a number of 246 patients with chronic liver disease, from whom 136 were diagnosed with chronic viral hepatitis and 110 with viral liver cirrhosis. These patients were assessed by using a clinical examination and a series of tests, including serum transaminase levels, serum bilirubin, serum albumin, markers of cholestasis, fasting plasma glucose levels, serum creatinine, urea, albuminuria, Addis-Hamburger test, electrophoresis of urinary proteins, abdominal ultrasound and, in some cases, CT examination. We obtained the following results: diabetes mellitus is often associated with chronic liver disease of viral etiology, having been identified in 18.29% of the patients in our study. Age above 60 in patients with chronic hepatitis (p=0.013<0.05) and presence of hepatitis C virus were particularly correlated with the presence of diabetes mellitus. Renal disease was present in 13.4% of the patients with chronic liver disease and it was especially associated with liver cirrhosis and hepatitis C virus. The most common form of renal injury was glomerulonephritis. Acute kidney injury was diagnosed only in cirrhotic patients as hepatorenal syndrome, occurring in 7.27% of the subjects, while chronic kidney disease was identified only in two cases of chronic viral hepatitis. Four patients in our study were diagnosed with HCC and none of them presented diabetes mellitus. DISCUSSION: Our study revealed that there is a significant association between diabetes mellitus and chronic viral liver disease induced by hepatitis C virus. Glomerulonephritis was the most common type of renal disease in both hepatitis patients and in those with cirrhosis. Glomerular injury was strongly correlated with the presence of hepatitis C virus than with hepatitis B virus. A connection between diabetes mellitus and hepatocellular carcinoma could not be established.

Clinical evolutional aspects of chronic subdural haematomas - literature review.

Apparently trivial, one of the most frequent pathologies in neurosurgical practice, chronic subdural haematoma, continues to be a challenge for the neurosurgeons both from the therapeutic and postoperatory complications point of view, taking into account that it is frequently met in elders, who usually present a complex pathology. The fact that, by definition, there is a latent period between the moment the brain injury, usually minor, occurs and the appearance of clinical symptomatology, frequently makes the trauma be ignored, this complicating the diagnosis and most of the times delaying the application of the adequate treatment. Developing slowly in time, in weeks or months, the aspect that chronic subdural haematoma usually occurs in elders should not be neglected, its clinical symptomatology often debuting with memory and attention disorders, so that the patient is usually referred to psychiatrists or neurologists, only a paraclinical investigation (CT scan or MRI) being able to establish the diagnosis. Even the appearance of the lateral signs is subjected to many diagnosis confusions because patients deny the existence of a trauma in over 50% of the cases.

Wireless Capsule Endoscopy in Correlation with Software Application in Gastrointestinal Diseases.

Wireless capsule endoscopy is one of the most recent investigation techniques of gastrointestinal pathology. Unlike conventional upper and lower endoscopy, it has the advantages of being a noninvasive and painless procedure. One of the capsule endoscopy disadvantages is represented by the necessary time to analyze the video frames obtained. Software applications proposed in this purpose could offer support in the images evaluation. Different algorithms have been described in the literature, but further research is needed to establish the practical value of computer vision tools in gastroenterology.

Particularities of Renal Manifestations in Chronic Viral Hepatitis.

INTRODUCTION: Chronic viral hepatitis represent major health problems worldwide, with an evolution that is sometimes marked by a series of extrahepatic manifestations. Among these, kidney disease may occur, either as glomerulonephritis, and/or renal dysfunction. MATERIAL AND METHODS: The purpose of this study was to achieve a complete assessment of the liver and kidney function in a series of patients diagnosed with chronic viral hepatitis, in order to identify a possible kidney disease in this context. 104 patients with chronic viral hepatitis B and C, aged between 25 and 80, were included in the study. These patients were assessed by a series of tests that allowed us to perform a complete evaluation of both liver and kidney function: liver cytolysis enzymes, serum bilirubin, markers of cholestasis, markers of viral infection, urinalysis, albuminuria, electrophoresis of urinary proteins, urea, creatinine, and abdominal ultrasound. RESULTS: Glomerular injury was a rare finding in patients with chronic hepatitis. Patients with chronic hepatitis B had glomerular disease in 5,88 % of cases, while 10 % of the patients with hepatitis C presented this type of renal disease. Acute kidney injury was not identified in our patient group. None of the patients in the hepatitis B study group presented chronic kidney disease. CKD was present in two patients with chronic hepatitis C that had no other associated conditions.

A comparison of the health status and psychological distress of partners of patients with a left ventricular assist device versus an implantable cardioverter defibrillator: a preliminary study.

OBJECTIVE: To examine if the caregiving for patients with a left ventricular assist device (LVAD) is related to a poorer health status and more distress compared to patients with an implantable cardioverter defibrillator (ICD). BACKGROUND: Partners distress may influence patient outcomes and is therefore an important aspect in the care of LVAD and ICD patients. METHODS: Multi-center prospective observational study with 6 months follow-up of 33 LVAD partners (27% men; mean age = 54 ± 10 years) and 414 ICD partners (22% men; mean age = 60 ± 12 years). RESULTS: LVAD partners reported better physical (F = 10.71, p = .001) but poorer mental health status (F = 14.82, p < .001) and higher depression scores compared to ICD partners (F = 3.68, p = .05) at 6 months follow-up, also in adjusted analyses. There was no significant difference between groups on anxiety. CONCLUSION: Caregivers of LVAD patients show higher distress levels compared to caregivers of ICD patients. LVAD partners may have a need for support beyond what is offered currently in clinical practice.

Preventing LVAD implantation by early short-term mechanical support and prolonged inodilator therapy : A case series with acute refractory cardiogenic shock treated with veno-arterial extracorporeal membrane oxygenation and optimised medical strategy.

Cardiogenic shock continues to be a life-threatening condition carrying a high mortality and morbidity, where the prognosis remains poor despite intensive modern treatment modalities. In recent years, mainly technical improvements have led to a more widespread use of short- and long-term mechanical circulatory support, such as veno-arterial extracorporeal membrane oxygenation (VA-ECMO) and left ventricular assist devices (LVADs). Currently, LVADs are indispensable as 'bridge' to cardiac recovery, heart transplantation (HTX), and/or as destination therapy Importantly, both LVADs and HTX put a vast burden on financial resources, besides significant short- and long-term risks of morbidity and mortality. These considerations underscore the importance of optimal timing and appropriate patient selection for LVAD therapy, avoiding as much as possible an unfortunate and costly clinical path. In this report, we present a series of three cases with acute refractory cardiogenic shock ('crash and burn', INTERMACS profile 1) successfully treated by ECMO and early optimal medical therapy preventing a certain path towards LVAD and/or HTX, for which they were initially referred. This conservative approach in INTERMACS profile one patients warrants very early introduction of adequate medical heart failure therapy under the umbrella of a combination of short-term mechanical circulatory and inotropic support by phosphodiesterase inhibitors. Therefore, this novel combined medical-mechanical approach could have important clinical implications for this extremely challenging patient category, as it may avoid an unnecessary and costly clinical path towards LVAD and/or heart transplantation.

Early assessment of glucose abnormalities during continuous glucose monitoring associated with lung function impairment in cystic fibrosis patients.

BACKGROUND: Cystic fibrosis-related diabetes (CFRD) is correlated with a decline in lung function. Under certain circumstances, oral glucose tolerance test (OGTT) screening, used to diagnose CFRD, fails to reveal early glucose tolerance abnormalities. In this situation, continuous glucose monitoring (CGM) could be a useful tool for evaluating early abnormalities of glucose tolerance in CF patients. We aimed to study the CGM glucose profile in CF patients with normal OGTT screening results and to evaluate lung function and nutritional status according to the CGM glucose profile. METHODS: We assessed glycemic control, the CGM glucose profile, nutritional status, lung function antibiotic courses and colonization (P. aeruginosa and S. aureus) in CF patients, aged 10 years and over, with normal screening OGTT results (blood glucose at T120 min < 7.8 mmol/l). Two groups were identified according to the max CGM glucose value: Group 1<11 mmol/l and Group 2 ≥ 11 mmol/l. RESULTS: Among the 38 patients with normal OGTT, 12 (31.6%) were in Group 2. Compared to Group 1, Group 2 patients exhibited a significant impairment in lung function: FEV1, 68.2 ± 25.6% vs. 87.3 ± 17%, p = 0.01 and FVC, 86.1% ± 19.4% vs. 99.3% ± 13.4%, p=0.021, as well as a higher rate of colonization by P. aeruginosa: 83.3% vs. 44%, p=0.024. Nevertheless, there were no differences in nutritional status (BMI standard deviation score: p = 0.079; prealbumin: p = 0.364). CONCLUSIONS: CGM reveals early abnormalities of glucose tolerance that remain undiagnosed by OGTT screening and are associated with worse lung function and a higher prevalence of P. aeruginosa colonization in patients with CF. CLINICAL TRIAL REGISTRATION NUMBER: NCT00476281.

Commissioning of an integrated platform for time-resolved treatment delivery in scanned ion beam therapy by means of optical motion monitoring.

The integrated use of optical technologies for patient monitoring is addressed in the framework of time-resolved treatment delivery for scanned ion beam therapy. A software application has been designed to provide the therapy control system (TCS) with a continuous geometrical feedback by processing the external surrogates tridimensional data, detected in real-time via optical tracking. Conventional procedures for phase-based respiratory phase detection were implemented, as well as the interface to patient specific correlation models, in order to estimate internal tumor motion from surface markers. In this paper, particular attention is dedicated to the quantification of time delays resulting from system integration and its compensation by means of polynomial interpolation in the time domain. Dedicated tests to assess the separate delay contributions due to optical signal processing, digital data transfer to the TCS and passive beam energy modulation actuation have been performed. We report the system technological commissioning activities reporting dose distribution errors in a phantom study, where the treatment of a lung lesion was simulated, with both lateral and range beam position compensation. The zero-delay systems integration with a specific active scanning delivery machine was achieved by tuning the amount of time prediction applied to lateral (14.61 ± 0.98 ms) and depth (34.1 ± 6.29 ms) beam position correction signals, featuring sub-millimeter accuracy in forward estimation. Direct optical target observation and motion phase (MPh) based tumor motion discretization strategies were tested, resulting in 20.3(2.3)% and 21.2(9.3)% median (IQR) percentual relative dose difference with respect to static irradiation, respectively. Results confirm the technical feasibility of the implemented strategy towards 4D treatment delivery, with negligible percentual dose deviations with respect to static irradiation.

Living donor liver transplantation with dual grafts -- a case report.

BACKGROUND: Living donor liver transplantation (LDLT) exposes to risks both the donor, due to a potential small residual liver volume, and the recipient, who faces the risk of small-for-size graft syndrome. In order to overcome these drawbacks, liver grafts from two different donors can be used. This paper presents a case of dual graft LDLT using a right hemiliver and a left lateral section from related donors. CASE PRESENTATION: A 14-year old female diagnosed with chronic hepatic failure due to Wilson's disease with Model-for-End- Stage-Liver-Disease score of 25, underwent a dual graft LDLT, receiving a right hemiliver with a reconstructed middle hepatic vein from her sister, and a left lateral section from her mother. None of the grafts complied with a satisfactory graft-to-recipient weight ratio (GRWR), if they would have been independently transplanted. The combined GRWR was 1.10. The donors and the recipient have been followed-up for over 1 year. RESULTS: The donors had no postoperative complications. The donors and the recipient were discharged 8 and 19 days after surgery, respectively. After 12-month follow-up, both donors and the recipient were alive, with normal graft function. CONCLUSION: Dual graft LDLT can be a feasible solution to overcome the risk of small-for-size graft syndrome. ABBREVIATIONS: BSA = body surface area, GRWR = graft-to-recipient weight ratio, GV SLV = recipient standard liver volume, HA = hepatic artery, HD = hepatic duct, HV = hepatic vein, LDLT = Living donor liver transplantation, LL = left lobe, LLS = left lateral section, MELD = Model for End-Stage Liver Disease, POD = postoperative day, PV = portal vein, RL = right lobe, SFS = small-for-size graft, SLV = standard liver volume, WD = Wilson's disease.

Tumor tracking based on correlation models in scanned ion beam therapy: an experimental study.

Accurate dose delivery to extra-cranial lesions requires tumor motion compensation. An effective compensation can be achieved by real-time tracking of the target position, either measured in fluoroscopy or estimated through correlation models as a function of external surrogate motion. In this work, we integrated two internal/external correlation models (a state space model and an artificial neural network-based model) into a custom infra-red optical tracking system (OTS). Dedicated experiments were designed and conducted at GSI (Helmholtzzentrum für Schwerionenforschung). A robotic breathing phantom was used to reproduce regular and irregular internal target motion as well as external thorax motion. The position of a set of markers placed on the phantom thorax was measured with the OTS and used by the correlation models to infer the internal target position in real-time. Finally, the estimated target position was provided as input for the dynamic steering of a carbon ion beam. Geometric results showed that the correlation models transversal (2D) targeting error was always lower than 1.3 mm (root mean square). A significant decrease of the dosimetric error with respect to the uncompensated irradiation was achieved in four out of six experiments, demonstrating that phase shifts are the most critical irregularity for external/internal correlation models.