Sarcopenia of kidney transplant recipients as a predictive marker for reduced graft function and graft survival after kidney transplantation.

PURPOSE: The association between sarcopenia of kidney transplant recipients and outcome after kidney transplantation (KT) has not yet been fully understood and is still considered controversial. The aim of our study was to analyze the impact of pre-transplant sarcopenia on graft function, postoperative complication rates, and survival of the patients after renal transplantation. METHODS: In this retrospective single-center study, all patients who underwent KT (01/2013-12/2017) were included. Demographic data, rejection rates, delayed graft function, and graft and patient survival rates were analyzed. Sarcopenia was measured in computed tomography images by the sex-adjusted Hounsfield unit average calculation (HUAC). RESULTS: During the study period, 111 single KTs (38 women and 73 men) were performed. Living donor kidney transplants were performed in 48.6%. In total, 32.4% patients had sarcopenia. Sarcopenic patients were significantly older (59.6 years vs. 49.8 years; p < 0.001), had a higher body mass index (BMI = 27.6 kg/m2 vs. 25.0 kg/m2; p = 0.002), and were more likely to receive deceased donor kidneys (72.2% vs. 41.3%; p = 0.002). Interestingly, 3 years after KT, the creatinine serum levels were significantly higher (2.0 mg/dl vs. 1.5 mg/dl; p = 0.001), whereas eGFR (39.9 ml/min vs. 53.4 ml/min; p = 0.001) and graft survival were significantly lower (p = 0.004) in sarcopenic transplant recipients. Sarcopenic patients stayed in hospital significantly longer postoperatively than those who were non-sarcopenic. CONCLUSIONS: At the time of kidney transplantation, sarcopenia was found to predict reduced long-term graft function and diminished graft survival after KT. The early identification of sarcopenic patients can not only enable an optimized selection of recipients, but also the initiation of pre-habilitation programs during the waiting period.

Effect of synthetic bone replacement material of different size on shear stress resistance within impacted native and thermodisinfected cancellous bone: an in vitro femoral impaction bone grafting model.

Antibiotic carrier particles of variable size might influence mechanic properties within impacted thermodisinfected and native cancellous bone different. Herafill®G containing calciumsulfate and calciumcarbonate provides high local concentrations of gentamicin being important for revision surgery in infected joint replacements. Native and thermodisinfected cancellous bone derived from 6 to 7 months old piglets was used for in vitro impaction bone grafting and supplemented each with Herafill®G granules of two different sizes. Micromovement of implants related to shear force was measured in 29 specimens distributed in 6 groups. Thermodisinfected cancellous bone revealed a significant higher shear force resistance than native bone with a mean difference of 423.8 mdeg/Nm (p < 0.001) ranging within 95% confidence interval from 181.5 to 666.0 mdeg/Nm. Adding small granules to thermodisinfected bone did not reduce shear force resistance significantly since adding large granules to native bone improved it by 344.0 mdeg/Nm (p < 0.003). Shear force resistance was found higher at the distal region of the implant compared to a proximal point of measurement throughout all specimens. Less impaction impulses were necessary for thermodisinfected bone. Thermodisinfected cancellous bone might achieve a higher degree of impaction compared with native bone resulting in increased resistance against shear force since impaction was found increased distally. Supplementation of thermodisinfected bone with small granules of Herafill®G might be considered for application of local antibiotics. Large granules appeared more beneficial for supplementation of native bone. Heterogeneity of bone graft and technical aspects of the impaction procedure have to be considered regarding the reproducibility of femoral impaction bone grafting.

Influence of antibiotic pellets on pore size and shear stress resistance of impacted native and thermodisinfected cancellous bone: An in vitro femoral impaction bone grafting model.

INTRODUCTION: Morphology and mechanic properties of impacted cancellous bone are affected by carrier substances which provide high local concentrations of antibiotics. METHODS: Bone chips were taken from the femoral head of 6-7 months old piglets. One half was thermodisinfected and the other remained native. Ten specimens each were mixed with Herafill® antibiotic pellets and a control group of each 10 specimens respectively was examined. The cancellous bone was impacted according to Exeter technique and the implants were cemented. The distribution of the particles and the pores were defined with three dimensional computertomographic scan and shear force resistance was measured until failure. RESULTS: Shear force resistance was not measured significantly less for thermodisinfected (2.7 Nm) compared with native bone (3.5 Nm) and addition of antibiotic pellets reduced shear force resistance in both groups since this was significant for the native group. The average pore volume of the native bone specimens appeared significant smaller compared to the thermodisinfected group (p = 0.011) and the pore volume showed a negative correlation with shear force resistance (p = 0.044). Pore volume around the pellets was found significantly increased and it appeared smaller for native bone. The number of pellets located next to the implant showed a negative correlation with shear force resistance (p = 0.034) and the negative correlation increased for pellets below the tip of the shaft model (p = 0.024). CONCLUSION: Adding antibiotic pellets to native and thermodisinfected impacted cancellous bone increased pore volume since the area around the pellets showed increased porosity which correlated with reduced shear force resistance. Computertomographic three dimensional measurement of porosity might predict shear force resistance of impacted cancellous bone and improve impaction of bone grafting intraoperatively.

Correlation of native T1 mapping with right ventricular function and pulmonary haemodynamics in patients with chronic thromboembolic pulmonary hypertension before and after balloon pulmonary angioplasty.

OBJECTIVES: The aim of this study was to assess native T1 mapping in patients with inoperable chronic thromboembolic pulmonary hypertension (CTEPH) before and 6 months after balloon pulmonary angioplasty (BPA) and compare the results with right heart function and pulmonary haemodynamics. METHODS: Magnetic resonance imaging at 1.5 T and right heart catheterisation were performed in 21 consecutive inoperable CTEPH patients before and 6 months after BPA. T1 values were measured within the septal myocardium, the upper and lower right ventricular insertion points, and the lateral wall at the basal short-axis section. In addition, the area-adjusted septal native T1 time (AA-T1) was calculated and compared with right ventricular function (RVEF), mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR). RESULTS: The mean AA-T1 value decreased significantly after BPA (1,045.8 ± 44.3 ms to 1,012.5 ± 50.4 ms; p < 0.001). Before BPA, native T1 values showed a moderate negative correlation with RVEF (r = -0.61; p = 0.0036) and moderate positive correlations with mPAP (r = 0.59; p < 0.01) and PVR (r = 0.53; p < 0.05); after BPA correlation trends were present (r = -0.21, r = 0.30 and r = 0.35, respectively). CONCLUSIONS: Native T1 values in patients with inoperable CTEPH were significantly lower after BPA and showed significant correlations with RVEF and pulmonary haemodynamics before BPA. Native T1 mapping seems to be indicative of reverse myocardial tissue remodelling after BPA and might therefore have good potential for pre-procedural patient selection, non-invasive therapy monitoring and establishing a prognosis. KEY POINTS: • BPA is a promising treatment option for patients with inoperable CTEPH • Native septal T1 values significantly decrease after BPA and show good correlations with right ventricular function and haemodynamics before BPA • Prognosis and non-invasive therapy monitoring might be supported in the future by native T1 mapping.

Multimodality imaging evaluation before transcatheter aortic valve implantation: incidence of contrast medium-induced acute kidney injury, risk factors and prognosis.

AIM: To evaluate the incidence, risk factors, and prognostic implications of contrast medium-induced acute kidney injury (CI-AKI) in patients undergoing transcatheter aortic valve implantation (TAVI) evaluation. MATERIALS AND METHODS: Datasets from 98 out of 207 consecutive patients referred for multidetector computed tomography (MDCT) for TAVI evaluation were eligible for evaluation and were analysed retrospectively. The incidence of CI-AKI was correlated to outcome and to potential risk factors: kidney function (estimated glomerular filtration rate [eGFR]), heart failure, diabetes, amount of contrast medium, and duration of examination period. RESULTS: CI-AKI occurred in 67 patients (68.4%) and mainly correlated with eGFR (p=0.01) and the amount of contrast medium as a function of eGFR (p=0.04). CI-AKI occurred before TAVI in 36 (53.7%) patients of which 13 (19.4%) did not undergo TAVI. In-hospital all-cause mortality was 21.4%, and of those 21 patients, 18 (85.7%) had CI-AKI and nine (42.9%) did not undergo TAVI. One-year all-cause mortality was 39.8%, and of those 39 patients who died within 1 year, 31 (79.5%) had CI-AKI. CONCLUSION: CI-AKI mostly occurs already before TAVI as a consequence of pre-procedural imaging, which therefore represents the main contributor for CI-AKI in relation to TAVI. Regarding the observation that some patients will ultimately have no benefit because TAVI is not performed and the poor prognosis linked to CI-AKI should encourage improvement in patient selection when referring to pre-procedural imaging.

[Influence of thermodisinfection on impaction of cancellous bone : An in vitro model of femoral impaction bone grafting]. / Einfluss der Thermodesinfektion auf die Impaktion spongiöser Knochen : Ein In-vitro-Modell für das femorale Impaction-Bone-Grafting.

BACKGROUND: The reconstruction of bony defects during endoprosthesis revision surgery using "impaction bone grafting" leads to the possibility of a longstanding osseous integration to achieve good clinical results. Native allogeneic cancellous bone is often used for the procedure. This study examines the influence of thermodisinfection on the impaction behaviour of cancellous bone of different geometries and on the cement distribution. METHODS: The cancellous bone was obtained from the femoral heads of 7­month old pigs. One half of the head was thermodisinfected while the other remained native. Bone chips with sizes of 3-5, 5-8 and 8-10 mm were produced. The impaction was performed in a cylinder model with an internal diameter of 30 mm and with standardized impaction force using an impactor with a weight of 1450 g. The best particle combination was used for the subsequent computer tomography examination of the cement distribution and the contact surface to the bone in different parts of the shaft in seven investigations. For statistic measurements two-dimensional variance analysis including repetitions of measurement and Bonferroni correction, the LSD post-hoc-zest and the Mann Whitney U Test were used. The error probability was set at α = 5%. The SPSS® for Windows software was used for the statistical analysis. RESULTS: The distribution of the cancellous and compacted bone also along the shaft revealed no significant difference between thermodisinfected and native cancellous bone at different levels (p > 0.05). Impacted native cancellous bone showed less inclusion of air, which resulted in a better distribution of density compared with thermodisinfected bone overall (p < 0.001). In the distal shaft area the cement volume was significantly larger in conjunction with the native bone. The overall area of cement penetration appeared to be significantly larger for native cancellous bone (p < 0.001). CONCLUSIONS: The impaction of thermodisinfected and native cancellous bone showed greater deformation of the processed bone without any significant difference in the maximum density reached at different levels. Cement volume and cement penetration were pronounced proximally in native and processed cancellous bone. The cement distribution was significantly more distal for the native bone. Distally, the stabilization of the shaft appears to be increasingly dependent on the density of the impacted spongiosa, while proximally, the penetration of the cement into cancellous bone seems to correlate with porosity.

[Mesenchymal abdominal tumors in children]. / Mesenchymale Tumoren des Abdomens bei Kindern.

Mesenchymal tumors in childhood comprise benign and malign entities and differ regarding typical sites of manifestation, age peak and clinical symptoms. In some cases biopsy is mandatory. If nephroblastoma is a possible diagnosis, biopsy must be avoided by all means in order to avoid biopsy tract metastasis. Imaging is used to narrow the differential diagnosis, describe the exact extent of the lesion and deliver complete staging. In pediatric patients sonography and MRI are the most important imaging modalities. Low-dose CT of the thorax serves for assessment of possible pulmonary metastases.

[Pulmonary embolism]. / Lungenembolie.

Pulmonary embolism is a potentially fatal disorder and frequently seen in critical care and emergency medicine. Due to a high mortality rate within the first few hours, the accurate initiation of rational diagnostic pathways in patients with suspected pulmonary embolism and timely consecutive treatment is essential. In this review, the current European guidelines on the diagnosis and therapy of acute pulmonary embolism are presented. Special focus is put on a structured patient management based on the individual risk of early mortality. In particular risk assessment and new risk-adjusted treatment recommendations are presented and discussed in this article.

[Diseases of connective tissue in IgG4-associated autoimmune diseases]. / Erkrankungen des Bindegewebes bei IgG4-assoziierten Autoimmunerkrankungen.

The IgG4-associated diseases of connective tissue are caused by allergen-mediated autoimmune processes. The retroperitoneum, mesentery and mediastinum as well as other less common localizations, such as the neck, orbit and periarticular connective tissue can be affected. Inflammatory fibrosis is initially dominated by a lymphocytic and plasma cell-rich infiltrate and later by cell-poor storiform fibrosis. Stenosis and occlusion of vessels, ureters and intestines can cause severe complications. Computed tomography (CT) and magnetic resonance imaging (MRI) can be implemented in the diagnostic algorithm to narrow the differential diagnosis, delineate the distribution of fibrosis and reveal complications.

[Imaging signs in chest diagnostics]. / Bildzeichen in der Thoraxdiagnostik.

Signs in chest imaging are defined as typical findings which can be easily recognized on x­ray photographs or computed tomography (CT) scans of the chest. They are caused by different typical pathophysiological processes. Due to the association of a certain pathophysiological cause with a given sign, knowledge and use of these signs can allow the possible differential diagnoses to be narrowed down. If other imaging findings and clinical data are additionally taken into account, the diagnosis can be made with a high degree of confidence in many cases.

Nano-Computed Tomography: Technique and Applications.

UNLABELLED: Nano-computed tomography (nano-CT) is an emerging, high-resolution cross-sectional imaging technique and represents a technical advancement of the established micro-CT technology. Based on the application of a transmission target X-ray tube, the focal spot size can be decreased down to diameters less than 400 nanometers (nm). Together with specific detectors and examination protocols, a superior spatial resolution up to 400 nm (10 % MTF) can be achieved, thereby exceeding the resolution capacity of typical micro-CT systems. The technical concept of nano-CT imaging as well as the basics of specimen preparation are demonstrated exemplarily. Characteristics of atherosclerotic plaques (intraplaque hemorrhage and calcifications) in a murine model of atherosclerosis (ApoE (-/-)/LDLR(-/-) double knockout mouse) are demonstrated in the context of superior spatial resolution in comparison to micro-CT. Furthermore, this article presents the application of nano-CT for imaging cerebral microcirculation (murine), lung structures (porcine), and trabecular microstructure (ovine) in contrast to micro-CT imaging. This review shows the potential of nano-CT as a radiological method in biomedical basic research and discusses the application of experimental, high resolution CT techniques in consideration of other high resolution cross-sectional imaging techniques. KEY POINTS: Nano-computed tomography is a high resolution CT-technology for 3D imaging at sub-micrometer resolution. The technical concept bases on a further development of the established ex-vivo-micro-CT technology. By improvement of the spatial resolution, structures at a cellular level become visible (e.g. osteocyte lacunae).

Changes in Dynamic Pelvic Floor Magnet Resonance Imaging and Patient Satisfaction after Resection Rectopexy for Obstructed Defecation Syndrome.

PURPOSE: Resection rectopexy (RR) provides good functional results and low recurrence rates for the treatment of obstructed defecation syndrome based on rectal prolapse and cul-de-sac syndrome, whereas little is known about changes in pelvic floor dynamics and patient satisfaction after surgery. MATERIALS AND METHODS: Within three years 26 consecutive female patients were prospectively included. Indications for RR (22 laparoscopic, 3 primary open and 1 converted-to-open) were rectal prolapse III° in 11 patients and cul-de-sac syndrome in 15 patients. Patients' quality of life (QOL), fecal behavior and defecation-associated pain were investigated before and after surgical treatment using anamnesis and clinical examination, Rand 36-idem health survey (SF-36), Cleveland-Clinic Incontinence Score (CCIS) and the visual analog scale for defecation-associated pain (VAS). Dynamic pelvic floor magnet resonance imaging (dPF-MRI) was used for the investigation of changes in pelvic floor anatomy and function before and after surgery. RESULTS: RR improved the rate of fecal incontinence (p < 0.01) and CCIS (p = 0.01). The use of laxatives (p = 0.01), the need for self-digitation (p = 0.02) and VAS (p < 0.01) were decreased, leading to improvements in QOL (overall p < 0.01). RR led to shortening of the H-line but not of the M-line under rest (p < 0.01) and during defecation (p = 0.04). A rectocele was co-incident in all patients in dPF-MRI before surgery. RR led to a reduction (p < 0.01) and declined protrusion (p = 0.03) of the rectocele. This results in a decreased rate of cul-de-sac (p < 0.01) and increased rate of complete defecation (p < 0.01) after surgery. At the 36-month follow-up no recurrence was observed. CONCLUSION: RR promises high rates of patient satisfaction and improvement in pelvic floor anatomy in select patients. KEY POINTS: • RR improves the pelvic floor anatomy of patients suffering from ODS. • RR improves the QOL of patients suffering from ODS. • An improvement in pelvic floor anatomy led to an improved QOL. • RR is an adequate treatment for select patients suffering from ODS.

[Pulmonary embolism]. / Lungenembolie.

Pulmonary embolism is a potentially fatal disorder and frequently seen in critical care and emergency medicine. Due to a high mortality rate within the first few hours, the accurate initiation of rational diagnostic pathways in patients with suspected pulmonary embolism and timely consecutive treatment is essential. In this review, the current European guidelines on the diagnosis and therapy of acute pulmonary embolism are presented. Special focus is put on a structured patient management based on the individual risk of early mortality. In particular risk assessment and new risk-adjusted treatment recommendations are presented and discussed in this article.

Development and Suggestion of a Cardiac CTA Scoring System for the Prediction of Revascularization Success in Chronic Total Occlusions (CTO) of the Coronary Arteries.

OBJECTIVE: Analyzing occluded segments with computed tomography angiography (CTA) prior to percutaneous coronary intervention (PCI) increased revascularization success in chronic total occlusions (CTO). The aim of our study was to develop a scoring system for the prediction of PCI success in CTO. MATERIALS AND METHODS: 41 consecutive CTO patients (30 male; 63.1 years +/- 8.3 standard deviation) underwent CTA prior to PCI. All CTOs were categorized by two radiologists in consensus regarding the presence of special features and without knowledge of PCI outcome. All outcome criteria were evaluated. Afterwards one point was assigned for each unequally distributed outcome criteria per CTO and all points were added up to a single score. RESULTS: Severe calcifications (failure group 68.8 % vs. success group 28.0 %; p < 0.02) and intraluminal calcifications (68.8 %; 40.0 %), tortuosity (25.0 %; 0 %; p < 0.02), linear intrathrombus enhancement (37.5 %; 60.0 %) and distal vessel disease (68.8 %; 44.0 %) were unequally distributed. By adopting a threshold of 4 points or higher (maximum 5 points), the results were: sensitivity 31.3 %, specificity 100 %, negative predictive value (NPV) 69.4 % and positive predictive value (PPV) 100 %. The PCI complication rate was 9.8 % and the mean contrast media amount was 234.4 ml. CONCLUSION: With the suggested scoring system, based on five CTA criteria, PCI failure could be predicted with high PPV and specificity in our group of patients, but the NPV and sensitivity are low. However, 5 unsuccessful PCIs (13.2 %) could have been avoided and none would have been wrongly omitted. Regarding the complication rate during PCI and the high amounts of contrast media needed, a prediction system appears to be desirable and should be the object of large-scale trials. KEY POINTS: Single predictors of revascularization success in CTO have been identified. Success rates are improved by analyzing CTA data sets prior to revascularization approaches. Prediction of revascularization success via a scoring system based on five CTA criteria seems promising. Patient selection for the right treatment options might be improved in the future due to application of the scoring system. Also risks, complications, contrast media amounts and radiation doses might be reduced.

MRI technique for the preoperative evaluation of deep infiltrating endometriosis: current status and protocol recommendation.

Endometriosis is a common cause of chronic pelvic pain and infertility. It is defined as the occurrence of endometrial tissue outside the uterine cavity and can manifest as a peritoneal, ovarian or infiltrating form, the latter being referred to as deep infiltrating endometriosis (DIE). Surgery is essential in the treatment of DIE and depending on the severity of the disease, surgery can be difficult and extensive. Beside clinical examination and ultrasound, magnetic resonance imaging (MRI) has proven its value to provide useful information for planning surgery in patients with suspected DIE. To optimise the quality of MRI examinations, radiologists have to be familiar with the capabilities and also the limitations of this technique with respect to the assessment of DIE. MRI yields morphological information by using mainly T1- and T2-weighted sequences, but can also provide functional information by means of intravenous gadolinium, diffusion-weighted imaging or cine-MRI. In this article, these techniques and also adequate measures of patient preparation, which are indispensable for successful MRI imaging for the preoperative evaluation of DIE, are reviewed and a comprehensive protocol recommendation is provided.

The impact of early surgical intervention in free intestinal perforation: a time-to-intervention pilot study.

PURPOSES: An abdominal inflammatory focus is the second most often source of sepsis with a high risk of death in surgical intensive care units. By establishing evidence-based bundled strategies the surviving sepsis campaign provided an optimized rapid and continuous treatment of these emergency patients. Hereby the hospital mortality decreased from 35 to 30 %. Sepsis treatment is based on three major therapeutic elements: surgical treatment (source control), antiinfective treatment, and supportive care. The international guidelines of the surviving sepsis campaign were updated recently and recommend rapid diagnosis of the infection and source control within the first 12 h after the diagnosis (grade 1c). Interestingly this recommendation is mainly based on studies on soft tissue infections. METHODS: In this retrospective analysis 76 septic patients with an intraabdominal inflammatory focus were included. All patients underwent surgery at different time-points after diagnosis. RESULTS: With 80 % patients of the early intervention group had an improved overall survival (vs. 73 % in the late intervention group). CONCLUSIONS: Literature on the time dependency of early source control is rare and in part contradicting. Results of this pilot study reveal that immediate surgical intervention might be of advantage for septic emergency patients. Further multi-center approaches will be necessary to evaluate, whether the TTI has any impact on the outcome of septic patients with intestinal perforation.

T1, T2 Mapping and Extracellular Volume Fraction (ECV): Application, Value and Further Perspectives in Myocardial Inflammation and Cardiomyopathies.

UNLABELLED: Cardiac magnetic resonance imaging (CMRI) is a versatile diagnostic tool. One of its main advantages is the possibility of tissue characterization. T1-weighted images for scar and T2-weighted images for edema visualization are key methods for tissue characterization. Otherwise these sequences are strongly limited for the detection of diffuse myocardial pathologies. Recently, rapid technical innovations have generated new techniques. T1, T2 mapping and evaluation of the extracellular volume fraction (ECV) allow quantification of diffuse myocardial pathologies and showed great potential in the visualization of fibrosis, edema, amyloid, iron overload and lipid. In the future these techniques might enable the detection of early cardiac involvement, even act as a prognosticator. Moreover, therapy monitoring and follow-up might be possible due to versatile parameter quantification with these new techniques. KEY POINTS: CMR allows for tissue characterization via T1- and T2-weighted sequences. In cases of diffuse, global myocardial pathologies, correct image interpretation with traditional CMR sequences might be difficult. T1, T2 mapping and ECV can quantify diffuse, global myocardial pathologies. Alterations of myocardial T1 and T2 relaxation times occur in various myocardial diseases (e.g. acute myocarditis). In the future mapping might act as a prognosticator or therapy monitoring tool.