RESUMEN
In computed tomography, coronary artery calcium (CAC) scores are influenced by image reconstruction. The effect of a newly introduced deep learning-based reconstruction (DLR) on CAC scoring in relation to other algorithms is unknown. The aim of this study was to evaluate the effect of four generations of image reconstruction techniques (filtered back projection (FBP), hybrid iterative reconstruction (HIR), model-based iterative reconstruction (MBIR), and DLR) on CAC detectability, quantification, and risk classification. First, CAC detectability was assessed with a dedicated static phantom containing 100 small calcifications varying in size and density. Second, CAC quantification was assessed with a dynamic coronary phantom with velocities equivalent to heart rates of 60-75 bpm. Both phantoms were scanned and reconstructed with four techniques. Last, scans of fifty patients were included and the Agatston calcium score was calculated for all four reconstruction techniques. FBP was used as a reference. In the phantom studies, all reconstruction techniques resulted in less detected small calcifications, up to 22%. No clinically relevant quantification changes occurred with different reconstruction techniques (less than 10%). In the patient study, the cardiovascular risk classification resulted, for all reconstruction techniques, in excellent agreement with the reference (κ = 0.96-0.97). However, MBIR resulted in significantly higher Agatston scores (61 (5.5-435.0) vs. 81.5 (9.25-435.0); p < 0.001) and 6% reclassification rate. In conclusion, HIR and DLR reconstructed scans resulted in similar Agatston scores with excellent agreement and low-risk reclassification rate compared with routine reconstructed scans (FBP). However, caution should be taken with low Agatston scores, as based on phantom study, detectability of small calcifications varies with the used reconstruction algorithm, especially with MBIR and DLR.
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Calcinosis , Enfermedad de la Arteria Coronaria , Humanos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Calcio , Valor Predictivo de las Pruebas , Tomografía Computarizada por Rayos X/métodos , Calcinosis/diagnóstico por imagen , Fantasmas de Imagen , Algoritmos , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/métodosRESUMEN
BACKGROUND: Pseudoprogression (PsP) or radiation necrosis (RN) may frequently occur after cranial radiotherapy and show a similar imaging pattern compared with progressive disease (PD). We aimed to evaluate the diagnostic accuracy of magnetic resonance imaging-based contrast clearance analysis (CCA) in this clinical setting. PATIENTS AND METHODS: Patients with equivocal imaging findings after cranial radiotherapy were consecutively included into this monocentric prospective study. CCA was carried out by software-based automated subtraction of imaging features in late versus early T1-weighted sequences after contrast agent application. Two experienced neuroradiologists evaluated CCA with respect to PsP/RN and PD being blinded for histological findings. The radiological assessment was compared with the histopathological results, and its accuracy was calculated statistically. RESULTS: A total of 33 patients were included; 16 (48.5%) were treated because of a primary brain tumor (BT), and 17 (51.1%) because of a secondary BT. In one patient, CCA was technically infeasible. The accuracy of CCA in predicting the histological result was 0.84 [95% confidence interval (CI) 0.67-0.95; one-sided P = 0.051; n = 32]. Sensitivity and specificity of CCA were 0.93 (95% CI 0.66-1.00) and 0.78 (95% CI 0.52-0.94), respectively. The accuracy in patients with secondary BTs was 0.94 (95% CI 0.71-1.00) and nonsignificantly higher compared with patients with primary BT with an accuracy of 0.73 (95% CI 0.45-0.92), P = 0.16. CONCLUSIONS: In this study, CCA was a highly accurate, easy, and helpful method for distinguishing PsP or RN from PD after cranial radiotherapy, especially in patients with secondary tumors after radiosurgical treatment.
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Neoplasias Encefálicas , Traumatismos por Radiación , Radiocirugia , Neoplasias Encefálicas/radioterapia , Medios de Contraste , Humanos , Imagen por Resonancia Magnética/efectos adversos , Imagen por Resonancia Magnética/métodos , Necrosis/etiología , Necrosis/cirugía , Estudios Prospectivos , Traumatismos por Radiación/diagnóstico por imagen , Traumatismos por Radiación/etiología , Traumatismos por Radiación/patologíaRESUMEN
The new Medical Licensing Regulations 2025 (Ärztliche Approbationsordnung, ÄApprO) will soon be passed by the Federal Council (Bundesrat) and will be implemented step by step by the individual faculties in the coming months. The further development of medical studies essentially involves an orientation from fact-based to competence-based learning and focuses on practical, longitudinal and interdisciplinary training. Radiation oncology and radiation therapy are important components of therapeutic oncology and are of great importance for public health, both clinically and epidemiologically, and therefore should be given appropriate attention in medical education. This report is based on a recent survey on the current state of radiation therapy teaching at university hospitals in Germany as well as the contents of the National Competence Based Learning Objectives Catalogue for Medicine 2.0 (Nationaler Kompetenzbasierter Lernzielkatalog Medizin 2.0, NKLM) and the closely related Subject Catalogue (Gegenstandskatalog, GK) of the Institute for Medical and Pharmaceutical Examination Questions (Institut für Medizinische und Pharmazeutische Prüfungsfragen, IMPP). The current recommendations of the German Society for Radiation Oncology (Deutsche Gesellschaft für Radioonkologie, DEGRO) regarding topics, scope and rationale for the establishment of radiation oncology teaching at the respective faculties are also included.
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Docentes Médicos , Oncología por Radiación , Competencia Clínica , Curriculum , Alemania , Humanos , Oncología por Radiación/educaciónRESUMEN
BACKGROUND: In radical radiochemotherapy (RCT) of inoperable non-small-cell lung cancer (NSCLC) typical prognostic factors include T- and N-stage, while there are still conflicting data on the prognostic relevance of gross tumor volume (GTV) and particularly its changes during RCT. The NCT03055715 study of the Young DEGRO working group of the German Society of Radiation Oncology (DEGRO) evaluated the prognostic impact of GTV and its changes during RCT. METHODS: A total of 21 university centers for radiation oncology from five different European countries (Germany, Switzerland, Spain, Belgium, and Austria) participated in the study which evaluated nâ¯= 347 patients with confirmed (biopsy) inoperable NSCLC in UICC stage III A/B who received radical curative-intent RCT between 2010 and 2013. Patient and disease data were collected anonymously via electronic case report forms and entered into the multi-institutional RadPlanBio platform for central data analysis. GTV before RCT (initial planning CT, GTV1) and at 40-50â¯Gy (re-planning CT for radiation boost, GTV2) was delineated. Absolute GTV before/during RCT and relative GTV changes were correlated with overall survival as the primary endpoint. Hazard ratios (HR) of survival analysis were estimated by means of adjusted Cox regression models. RESULTS: GTV1 was found to have a mean of 154.4â¯ml (95%CI: 1.5-877) and GTV2 of 106.2â¯ml (95% CI: 0.5-589.5), resulting in an estimated reduction of 48.2â¯ml (pâ¯< 0.001). Median overall survival (OS) was 18.8 months with a median of 22.1, 20.9, and 12.6 months for patients with high, intermediate, and low GTV before RT. Considering all patients, in one survival model of overall mortality, GTV2 (2.75 (1.12-6.75, pâ¯= 0.03) was found to be a stronger survival predictor than GTV1 (1.34 (0.9-2, pâ¯> 0.05). In patients with available data on both GTV1 and GTV2, absolute GTV1 before RT was not significantly associated with survival (HR 0-69, 0.32-1.49, pâ¯> 0.05) but GTV2 significantly predicted OS in a model adjusted for age, T stage, and chemotherapy, with an HR of 3.7 (1.01-13.53, pâ¯= 0.04) per 300â¯ml. The absolute decrease from GTV1 to GTV2 was correlated to survival, where every decrease by 50â¯ml reduced the HR by 0.8 (CI 0.64-0.99, pâ¯= 0.04). There was no evidence for a survival effect of the relative change between GTV1 and GTV2. CONCLUSION: Our results indicate that independently of T stage, the re-planning GTV during RCT is a significant and superior survival predictor compared to baseline GTV before RT. Patients with a high absolute (rather than relative) change in GTV during RT show a superior survival outcome after RCT.
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Carcinoma de Pulmón de Células no Pequeñas/terapia , Quimioradioterapia , Neoplasias Pulmonares/terapia , Carga Tumoral , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Pulmón de Células no Pequeñas/patología , Estudios de Cohortes , Europa (Continente) , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Neoplasias Pulmonares/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Dosificación Radioterapéutica , Estudios Retrospectivos , Resultado del Tratamiento , Carga Tumoral/efectos de la radiaciónRESUMEN
PURPOSE: Medical students' knowledge of radiation oncology (RO) is of increasing importance with a rising prevalence of malignancies. However, RO teaching in medical schools is heterogeneous and has not been analyzed at a federal level yet. Therefore, the following survey aims to provide a national overview of RO teaching in Germany. METHODS: A questionnaire containing multiple-choice and free-text questions covering the extent and topics of RO teaching was sent to RO departments of all university hospitals in Germany and was answered by the heads of department/main lecturers. RESULTS: 24/35 (68.6%) RO departments returned completed forms. Most faculties employ lectures (91.7%), seminars (87.5%), and practical/bedside training (75.0%), whereas training in radiation biology and medical physics are rare (25% and 33.3%, respectively). Main topics covered are general RO (100%), radiation biology (91.7%), and side effects (87.5%). Regarding RO techniques and concepts, image-guided and intensity-modulated radiotherapy are taught at all faculties, followed by palliative and stereotactic techniques (87.5% each). Notably, all departments offered at least a partial rotation in RO in conjunction with radiology and/or nuclear medicine departments in the last year of medical school, while only 70.8% provided a complete rotation in RO. In addition, 57.1% of the departments have taken measures concerning the upcoming National Competence-Based Learning Objectives Catalogue (NKLM) for medical education. CONCLUSION: RO plays an integral but underrepresented role in clinical medical education in Germany, but faces new challenges in the development of practical and competence-based education, which will require further innovative and interdisciplinary concepts.
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Oncología por Radiación/educación , Encuestas y Cuestionarios , Curriculum , Docentes Médicos , Alemania , Hospitales Universitarios , Humanos , Revisión por Expertos de la Atención de Salud , Sociedades Médicas , EnseñanzaRESUMEN
PURPOSE: Chronic kidney disease (CKD) is prevalent in transcatheter aortic valve replacement (TAVR) candidates, leading to concerns regarding contrast medium (CM) safety. We evaluated (a) the impact of low-CM imaging on pre-TAVR measurements and (b) postcontrast acute kidney injury (PC-AKI) prevalence after dual-source computed tomography (DSCT) in TAVR candidates. METHODS: All TAVR candidates with CKD (SCr≥1.5 mg/dL) who underwent weight-based low-CM, low-pitch helical 3rd-generation DSCT in a one-year period were included, and matched to standard-CM, non-CKD controls (N = 50). Image quality (IQ) and pre-TAVR measurement interobserver variability were evaluated. Renal function change and PC-AKI were studied in the entire TAVR cohort, irrespective of scan mode (N = 153). RESULTS: Low-CM in CKD (N = 25) was performed with median 68 mL CM [52-87], 90 kV [80-90] and SCr 1.6 mg/dL [1.5-1.9], and standard-CM without CKD with median 116 mL CM [96-134], 100 kV [90-110] and SCr 1.0 mg/dL [0.9-1.1](P < 0.00). Low-CM IQ was good, though lower compared with standard-CM (P < 0.02). Interobserver measurement reliability was excellent (ICCs>0.85). Interobserver-agreement was lower in low-CM, causing prosthesis size disagreement in 5/25 (kappa-0.73) versus 0/25 with standard-CM (kappa-1.00), and transfemoral eligibility disagreement in 4/25 (kappa-0.68) versus 2/25 (kappa-0.84), respectively. Mean 1-month SCr-change in the low-CM TAVR cohort (N = 35) was -1 % [-12 to +7 %] and in standard-CM (N = 118) 0 % [-8 to +10 %](P > 0.3). PC-AKI occurred in none. CONCLUSION: Low-CM third-generation-DSCT achieves good IQ in TAVR candidates with CKD, and seems safe, with no apparent renal function deterioration or prevalence of PC-AKI. However, standard-CM protocols in non-CKD patients provide higher measurement reproducibility. Low-CM protocols should therefore be reserved for patients at high risk for PC-AKI.
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Válvula Aórtica/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Medios de Contraste , Intensificación de Imagen Radiográfica/métodos , Reemplazo de la Válvula Aórtica Transcatéter/instrumentación , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Anciano de 80 o más Años , Válvula Aórtica/cirugía , Femenino , Humanos , Masculino , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados , Estudios RetrospectivosRESUMEN
BACKGROUND AND PURPOSE: Radiation necrosis is a possible adverse event after cranial radiation therapy and can cause severe symptoms, such as an increased intracranial pressure or neurological deterioration. The vascular endothelial growth factor (VEGF) inhibitor bevacizumab (BEV) has been shown to be a feasible therapeutic option for symptomatic radiation necrosis, either when traditional antiedematous steroid treatment fails, or as an alternative to steroid treatment. However, to the best of our knowledge, only one randomized study with a rather small cohort exists to prove a beneficial effect in this setting. Therefore, further real-life data are needed. This retrospective monocentric case study evaluates patients who received BEV due to radiation necrosis, with a specific focus on the respective clinical course. METHODS: Using the internal database for pharmaceutical products, all patients who received BEV in our department were identified. Only patients who received BEV as symptomatic treatment for radiation necrosis were included. Patient characteristics, symptoms before, during, and after treatment, and the use of dexamethasone were evaluated using medical reports and systematic internal documentation. The symptoms were graded using CTCAE version 5.0 for general neurological symptoms. Symptoms were graded directly before each cycle and after the treatment (approximately 6 weeks). Additionally, the daily steroid dose was collected at these timepoints. Patients who either improved in symptoms, received less dexamethasone after treatment, or both were considered to have a benefit from the treatment. RESULTS: Twenty-one patients who received BEV due to radiation necrosis were identified. For 10 patients (47.6%) symptoms improved and 11 patients (52.4%) remained clinically stable during the treatment. In 14 patients (66.7%) the dexamethasone dose could be reduced during therapy, 5 patients (23.8%) received the same dose of dexamethasone before and after the treatment, and 2 patients (9.5%) received a higher dose at the end of the treatment. According to this analysis, overall, 19 patients (90.5%) benefited from the treatment with BEV. No severe adverse effects were reported. CONCLUSION: BEV might be an effective and safe therapeutic option for patients with radiation necrosis as a complication after cranial radiation therapy. Patients seem to benefit from this treatment by improving symptomatically or through reduction of dexamethasone.
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Bevacizumab/uso terapéutico , Encéfalo/efectos de la radiación , Irradiación Craneana/efectos adversos , Traumatismos por Radiación/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Estudios de Cohortes , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Necrosis , Tomografía Computarizada por Tomografía de Emisión de Positrones , Traumatismos por Radiación/diagnóstico por imagen , Estudios RetrospectivosRESUMEN
BACKGROUND: The 18-kDa translocator protein (TSPO) is overexpressed in brain tumours and represents an interesting target for glioma imaging. 18F-GE-180, a novel TSPO ligand, has shown improved binding affinity and a high target-to-background contrast in patients with glioblastoma. However, the association of uptake characteristics on TSPO PET using 18F-GE-180 with the histological WHO grade and molecular genetic features so far remains unknown and was evaluated in the current study. METHODS: Fifty-eight patients with histologically validated glioma at initial diagnosis or recurrence were included. All patients underwent 18F-GE-180 PET, and the maximal and mean tumour-to-background ratios (TBRmax, TBRmean) as well as the PET volume were assessed. On MRI, presence/absence of contrast enhancement was evaluated. Imaging characteristics were correlated with neuropathological parameters (i.e. WHO grade, isocitrate dehydrogenase (IDH) mutation, O-6-methylguanine-DNA methyltransferase (MGMT) promoter methylation and telomerase reverse transcriptase (TERT) promoter mutation). RESULTS: Six of 58 patients presented with WHO grade II, 16/58 grade III and 36/58 grade IV gliomas. An (IDH) mutation was found in 19/58 cases, and 39/58 were classified as IDH-wild type. High 18F-GE-180-uptake was observed in all but 4 cases (being WHO grade II glioma, IDH-mutant). A high association of 18F-GE-180-uptake and WHO grades was seen: WHO grade IV gliomas showed the highest uptake intensity compared with grades III and II gliomas (median TBRmax 5.15 (2.59-8.95) vs. 3.63 (1.85-7.64) vs. 1.63 (1.50-3.43), p < 0.001); this association with WHO grades persisted within the IDH-wild-type and IDH-mutant subgroup analyses (p < 0.05). Uptake intensity was also associated with the IDH mutational status with a trend towards higher 18F-GE-180-uptake in IDH-wild-type gliomas in the overall group (median TBRmax 4.67 (1.56-8.95) vs. 3.60 (1.50-7.64), p = 0.083); however, within each WHO grade, no differences were found (e.g. median TBRmax in WHO grade III glioma 4.05 (1.85-5.39) vs. 3.36 (2.32-7.64), p = 1.000). No association was found between uptake intensity and MGMT or TERT (p > 0.05 each). CONCLUSION: Uptake characteristics on 18F-GE-180 PET are highly associated with the histological WHO grades, with the highest 18F-GE-180 uptake in WHO grade IV glioblastomas and a PET-positive rate of 100% among the investigated high-grade gliomas. Conversely, all TSPO-negative cases were WHO grade II gliomas. The observed association of 18F-GE-180 uptake and the IDH mutational status seems to be related to the high inter-correlation of the IDH mutational status and the WHO grades.
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Neoplasias Encefálicas , Glioma , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Carbazoles , Glioma/diagnóstico por imagen , Glioma/genética , Humanos , Biología Molecular , Mutación , Clasificación del Tumor , Recurrencia Local de Neoplasia , Tomografía de Emisión de Positrones , Receptores de GABARESUMEN
BACKGROUND: PET represents a valuable tool for glioma imaging. In addition to amino acid tracers such as 18F-FET, PET targeting the 18-kDa mitochondrial translocator-protein (TSPO) is of high interest for high-grade glioma (HGG) imaging due to its upregulation in HGG cells. 18F-GE-180, a novel TSPO ligand, has shown a high target-to-background contrast in HGG. Therefore, we intra-individually compared its uptake characteristics to dynamic 18F-FET PET and contrast-enhanced MRI in patients with HGG. METHODS: Twenty HGG patients (nine IDH-wildtype, 11 IDH-mutant) at initial diagnosis (n = 8) or recurrence (n = 12) were consecutively included and underwent 18F-GE-180 PET, dynamic 18F-FET PET, and MRI. The maximal tumour-to-background ratios (TBRmax) and biological tumour volumes (BTV) were evaluated in 18F-GE-180 and 18F-FET PET. Dynamic 18F-FET PET analysis included the evaluation of minimal time-to-peak (TTPmin). In MRI, the volume of contrast-enhancement was delineated (VOLCE). Volumes were spatially correlated using the Sørensen-Dice coefficient. RESULTS: The median TBRmax tended to be higher in 18F-GE-180 PET compared to 18F-FET PET [4.58 (2.33-8.95) vs 3.89 (1.56-7.15); p = 0.062] in the overall group. In subgroup analyses, IDH-wildtype gliomas showed a significantly higher median TBRmax in 18F-GE-180 PET compared to 18F-FET PET [5.45 (2.56-8.95) vs 4.06 (1.56-4.48); p = 0.008]; by contrast, no significant difference was observed in IDH-mutant gliomas [3.97 (2.33-6.81) vs 3.79 (2.01-7.15) p = 1.000]. Only 5/20 cases showed higher TBRmax in 18F-FET PET compared to 18F-GE-180 PET, all of them being IDH-mutant gliomas. No parameter in 18F-GE-180 PET correlated with TTPmin (p > 0.05 each). There was a tendency towards higher median BTVGE-180 [32.1 (0.4-236.0) ml] compared to BTVFET [19.3 (0.7-150.2) ml; p = 0.062] with a moderate spatial overlap [median Sørensen-Dice coefficient 0.55 (0.07-0.85)]. In MRI, median VOLCE [9.7 (0.1-72.5) ml] was significantly smaller than both BTVFET and BTVGE180 (p < 0.001 each), leading to a poor spatial correlation with BTVGE-180 [0.29 (0.01-0.48)] and BTVFET [0.38 (0.01-0.68)]. CONCLUSION: PET with 18F-GE-180 and 18F-FET provides differing imaging information in HGG dependent on the IDH-mutational status, with diverging spatial overlap and vast exceedance of contrast-enhancement in MRI. Combined PET imaging might reveal new insights regarding non-invasive characterization of tumour heterogeneity and might influence patients' management.
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Carbazoles , Glioma/diagnóstico por imagen , Glioma/patología , Tomografía de Emisión de Positrones/métodos , Tirosina/análogos & derivados , Adulto , Anciano , Transporte Biológico , Neoplasias Encefálicas/diagnóstico por imagen , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Carbazoles/metabolismo , Femenino , Glioma/genética , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Clasificación del Tumor , Proyectos Piloto , Polimorfismo Genético , Trazadores Radiactivos , Receptores de GABA/genética , Carga Tumoral , Tirosina/metabolismoRESUMEN
OBJECTIVE: The 18-kDa mitochondrial translocator protein (TSPO) was reported to be upregulated in gliomas. 18F-GE-180 is a novel 3rd generation TSPO receptor ligand with improved target-to-background contrast compared to previous tracers. In this pilot study, we compared PET imaging with 18F-GE-180 and MRI of patients with untreated and recurrent pretreated glioblastoma. METHODS: Eleven patients with histologically confirmed IDH wildtype gliomas (10 glioblastomas, 1 anaplastic astrocytoma) underwent 18F-GE-180 PET at initial diagnosis or recurrence. The PET parameters mean background uptake (SUVBG), maximal tumour-to-background ratio (TBRmax) and PET volume using different thresholds (SUVBG × 1.6, 1.8 and 2.0) were evaluated in the 60-80 min p.i. summation images. The different PET volumes were compared to the contrast-enhancing tumour volume on MRI. RESULTS: All gliomas were positive on 18F-GE-180 PET and were depicted with extraordinarily high tumour-to-background contrast (median SUVBG 0.47 (0.37-0.93), TBRmax 6.61 (3.88-9.07)). 18F-GE-180 uptake could be found even in areas without contrast enhancement on MRI, leading to significantly larger PET volumes than MRI-based volumes (median 90.5, 74.5, and 63.8 mL vs. 31.0 mL; p = 0.003, 0.004, 0.013). In percentage difference, the PET volumes were on average 179%, 135%, and 90% larger than the respective MRI volumes. The median spatial volumetric correlation (Sørensen-Dice coefficient) of PET volumes and MRI volumes prior to radiotherapy was 0.48, 0.54, and 0.58. CONCLUSION: 18F-GE-180 PET provides a remarkably high tumour-to-background contrast in untreated and pretreated glioblastoma and shows tracer uptake even beyond contrast enhancement on MRI. To what extent 18F-GE-180 uptake reflects the tumour extent of human gliomas and inflammatory cells remains to be evaluated in future prospective studies with guided stereotactic biopsies and correlation of histopathological results.
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Carbazoles , Glioblastoma/diagnóstico por imagen , Glioblastoma/metabolismo , Tomografía de Emisión de Positrones , Receptores de GABA/metabolismo , Femenino , Humanos , Ligandos , Masculino , Persona de Mediana Edad , Proyectos Piloto , RecurrenciaRESUMEN
Several social mammals, including elephants and some primates, whales and bats, live in multilevel societies that form temporary subgroups. Despite these fission-fusion dynamics, group members often maintain long-term bonds. However, it is unclear whether such individual links and the resulting stable social subunits continue to exist after a complete reorganisation of a society, e.g. following a population crash. Here, we employed a weighted network analysis on 7,109 individual roosting records collected over 4 years in a wild Bechstein's bat colony. We show that, in response to a strong population decline, the colony's two stable social subunits fused into a non-modular social network. Nevertheless, in the first year after the crash, long-term bonds were still detectable, suggesting that the bats remembered previous individual relationships. Our findings are important for understanding the flexibility of animal societies in the face of dramatic changes and for the conservation of social mammals with declining populations.
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Conducta Animal , Quirópteros/fisiología , Conducta Social , Animales , Femenino , Masculino , Dinámica PoblacionalRESUMEN
The purpose was to evaluate the accuracy of multidetector CT angiography (MD-CTA) in the morphologic assessment of peripheral arterial occlusive disease (PAOD) compared to digital subtraction angiography (DSA). Fifty consecutive patients referred for DSA of the peripheral arteries due to PAOD were prospectively included in this study and underwent 16-row MD-CTA prior to DSA. Maximum intensity projections and multipath curved planar reformations were created with a semi-automated toolbox. Twenty-one vascular segments were defined in each leg and compared to DSA findings with regard to gradation, length, and number of lesions. Mean sensitivity and specificity in the detection of significant stenoses (over 70%) were 100% and 99.5% in the iliac arteries, 97.4% and 99.0% in the femoro-popliteal arteries, and 98.3% and 99.8% in the infrapopliteal arteries, respectively. High kappa values for exact stenoses gradation (0.74-1), lesion length (0.74-1), and number of lesions (0.71-1) were reached by MD-CTA, indicating high agreement with DSA. Non-invasive MD-CTA is an accurate tool for the assessment of all treatment-relevant morphologic information of PAOD (gradation, length, and number of stenoses) compared to DSA.
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Angiografía/métodos , Arteriopatías Oclusivas/diagnóstico por imagen , Pierna/irrigación sanguínea , Enfermedades Vasculares Periféricas/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto , Anciano , Anciano de 80 o más Años , Angiografía de Substracción Digital , Arteriopatías Oclusivas/patología , Medios de Contraste , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedades Vasculares Periféricas/patología , Interpretación de Imagen Radiográfica Asistida por Computador , Sensibilidad y Especificidad , Índice de Severidad de la EnfermedadRESUMEN
Personality dimensions of participants who suffer from visual stress were compared with those of normal participants using the Eysenck Personality Inventory. Extraversion-Introversion scores showed no significant differences between the participants who suffered visual stress and those who were classified as normal. By contrast, significant differences were found between the normal participants and those with visual stress in respect of Neuroticism-Stability. These differences accord with Eysenck's personality theory which states that those who score highly on the neuroticism scale do so because they have a neurological system with a low threshold such that their neurological system is easily activated by external stimuli. The findings also relate directly to the theory of visual stress proposed by Wilkins which postulates that visual stress results from an excess of neural activity. The data may indicate that the excess activity is likely to be localised at particular neurological regions or neural processes.
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Distorsión de la Percepción/fisiología , Determinación de la Personalidad , Personalidad , Trastornos de la Visión/psicología , Percepción Visual/fisiología , Adolescente , Adulto , Color , Extraversión Psicológica , Femenino , Fusión de Flicker , Humanos , Introversión Psicológica , Masculino , Modelos Psicológicos , Lectura , Valores de Referencia , Auxiliares Sensoriales , Índice de Severidad de la Enfermedad , Estadística como AsuntoRESUMEN
PURPOSE: To determine the primary success and short-term patency of stent application as a primary treatment modality for high-grade lesions of the infrapopliteal arteries compared with treatment with percutaneous transluminal angioplasty (PTA) in critical limb ischemia in a randomized prospective study. METHODS: Endovascular therapy was performed on 95 lesions in 51 patients (mean age 72.0 years, range 47-80 years) who presented clinically with Fontaine stages III and IV. One patient underwent treatment in both limbs. After angiographic lesion identification, patients were randomized for treatment by PTA (53 lesions in 27 patients) or stent application (42 lesions in 24 patients). Follow-up by clinical investigation and conventional angiography or spiral CT angiography was performed in 37 patients (57 lesions) 6 to 12 months after the procedure, or when clinically indicated. Evaluation was performed by two observers, double-blinded, with thresholds for lesion restenosis of 50% and 70%. Statistical evaluation was performed on a lesion basis by Kaplan-Meier estimated probability rates, and log-rank and Wilcoxon tests. The primary endpoint was the angiographic patency rate of treated lesions. RESULTS: The inter-reader agreement was high (kappa = 0.82). For the stent group the cumulative primary patency at 6 months was 83.7% at the 70% restenosis threshold, and 79.7% at the 50% restenosis threshold. For PTA, the primary patency at 6 months was 61.1% at the 70% restenosis threshold and 45.6% at the 50% restenosis threshold. Both results were statistically significant (p < 0.05). CONCLUSION: Infrapopliteal stent application is an effective treatment modality for high-grade lesions in chronic critical limb ischemia. Compared with PTA, higher patency rates can be expected after 6 months.
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Angioplastia de Balón , Isquemia/cirugía , Pierna/irrigación sanguínea , Arteria Poplítea/cirugía , Stents , Anciano , Anciano de 80 o más Años , Carbono , Materiales Biocompatibles Revestidos , Método Doble Ciego , Femenino , Humanos , Isquemia/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Proyectos Piloto , Arteria Poplítea/diagnóstico por imagen , Estudios Prospectivos , Radiografía , Estadísticas no Paramétricas , Análisis de Supervivencia , Resultado del Tratamiento , Grado de Desobstrucción VascularRESUMEN
The aim of this study was to analyze pulmonary embolism (PE) occurrence and retrospective clinical outcome in patients with clinically suspected acute PE and a negative spiral CT angiography (SCTA) of the pulmonary arteries. Within a 35-month period, 485 consecutive patients with clinical symptoms of acute PE underwent SCTA of the pulmonary arteries. Patients with a negative SCTA and without anticoagulation treatment were followed-up and formed the study group. Patient outcome and recurrence of PE was evaluated retrospectively during a period of 6 months after the initial SCTA, and included a review of computerized patient records, and interviews with physicians and patients. Patients were asked to fill out a questionnaire concerning all relevant questions about their medical history and clinical course during the follow-up period. Special attention was focused on symptoms indicating recurrent PE, as well as later confirmation and therapy of PE. Of the 485 patients, 325 patients (67%) had a negative scan, 134 (27.6%) had radiological signs of PE, and 26 (5.4%) had an indeterminant result. Of 325 patients with a negative scan, 269 (83%) were available for follow-up. The main reasons for loss to follow-up were change of address, name, or phone number, or non-resident patients who left abroad. Of 269 patients available for follow-up, 49 patients (18.2% of 269) received anticoagulant treatment because of prior or recent deep venous thrombosis (32.6%) or a history of PE (34.7%), cardiovascular disease (18.4%), high clinical probability (8.2%), positive ventilation-perfusion scan (4.2%), and elevated D-dimer test (2%). The remaining 220 patients, who did not receive anticoagulant medication, formed the study group. Of this study group, 1 patient died from myocardial infarction 6 weeks after the initial SCTA, and the postmortem examination also detected multiple peripheral emboli in both lungs ( p=0.45%; 0.01-2.5, 95% confidence interval). The PE did not occur in any other patient. In patients with suspected PE and negative SCTA without anticoagulant therapy, the risk of recurrent PE in this study was less than 1% and similar to that in patients after a negative pulmonary angiogram. Therefore, we conclude that patients can be managed safely without anticoagulation therapy; however, this approach may not be appropriate for critically ill patients and those with persistent high clinical suspicion of acute PE.
Asunto(s)
Embolia Pulmonar/diagnóstico por imagen , Embolia Pulmonar/epidemiología , Tomografía Computarizada Espiral/métodos , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Intervalos de Confianza , Reacciones Falso Negativas , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Probabilidad , Estudios Retrospectivos , Medición de Riesgo , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Distribución por Sexo , Tasa de SupervivenciaRESUMEN
Acute myocardial infarction following blunt chest trauma is a well reported but rare finding. Especially in severely injured patients the optimal therapy of the myocardial infarction is not well established, since anticoagulants, platelet aggregation inhibitors or thrombolytics are frequently contraindicated under these conditions. We report a case of a 41-year-old man, who presented with an acute myocardial infarction in combination with a severe polytrauma (multiple rib fractures, hematothorax, pelvic bone fractures, multiple injuries of intestinal organs) after a motorcycle accident with a blunt chest and abdominal trauma. After surgical treatment of the injuries of the bones and the intestinal organs a coronary angiography was immediately performed. The left anterior descending and the circumflex coronary artery were occluded in the mid-portion of the vessels. Coronary recanalization by PTCA and the implantation of coronary stents were successful in both vessels. Despite of a non-optimal blood flow after recanalization and stenting in one vessel (LAD TIMI II flow after recanalization), and a non-optimal accompanying medical therapy, during and after intervention (intravenous heparin starting 8 hours after the coronary intervention and platelet inhibitors starting 4 days after the intervention) the coronary angiogram after 2 months documented both vessels patent without a reocclusion or a restenosis. The case report documents, that in traumatic myocardial infarctions the treating of both, the attending injuries and the myocardial ischemia, is feasible. Early coronary angiography and coronary interventions, with or without stent-implantation, are indicated, even in cases in which an adequate accompanying medical therapy with heparin and platelet inhibitors is contraindicated.
Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Traumatismo Múltiple/terapia , Infarto del Miocardio/etiología , Infarto del Miocardio/terapia , Heridas no Penetrantes/complicaciones , Accidentes de Tránsito , Adulto , Angiografía Coronaria , Vasos Coronarios/cirugía , Electrocardiografía , Humanos , Masculino , Motocicletas , Infarto del Miocardio/diagnóstico , Esterilización ReproductivaRESUMEN
Computed tomography angiography (CTA) is today a well-established diagnostic technique for non-invasive vascular imaging and has replaced diagnostic intra-arterial angiography. Especially since the implementation of multi detector-row computed tomography (MDCT) the acquisition of isotropic data sets is possible, thus widening the spectrum of clinical application of multi detector-row computed tomography. Compared to intra-arterial angiography computed tomography angiography is less invasive and cheaper.
Asunto(s)
Angiografía/instrumentación , Procesamiento de Imagen Asistido por Computador/instrumentación , Imagenología Tridimensional/instrumentación , Tomografía Computarizada por Rayos X/instrumentación , Enfermedades Vasculares/diagnóstico , Arterias/patología , Medios de Contraste/administración & dosificación , Diseño de Equipo , Humanos , Sensibilidad y Especificidad , Tomografía Computarizada Espiral/instrumentaciónRESUMEN
The aim of this study was to investigate equipment availability and current diagnostic strategies for suspected pulmonary embolism (PE) in Austrian hospitals. A questionnaire was sent to the medical directors of all Austrian hospitals with emergency and/or surgical, orthopedic, and medical departments. The questionnaire contained questions regarding the available equipment suitable for the imaging diagnosis of PE, the first-line and second-line imaging tests for patients with suspected PE, and additional lower extremity venous imaging and laboratory tests that complement the diagnostic armamentarium. The return rate for questionnaires was 81% (127 of 157 hospitals). There were 97% of hospitals that had the equipment to perform sonography, 59% could perform pulmonary angiography, 54% spiral CT, 19% ventilation/perfusion (V/P) scintigraphy, and 4% perfusion scintigraphy alone. Spiral-CT angiography (SCTA) was the first-line imaging study for suspected PE in 56% of hospitals, followed by echocardiography and V/P scintigraphy. Lower extremity venous imaging (47%) and, interestingly, V/P scintigraphy (43%), served as second-line imaging tests. D-dimer tests were included in the diagnostic strategy in 74% of hospitals. Spiral-CT angiography is the most commonly used primary method for suspected PE in Austrian hospitals. The V/P scintigraphy is available only in a minority of hospitals to investigate patients with suspected PE. When V/P scintigraphy is available, however, it is employed in a large number of patients per annum.