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1.
Neuroimage Clin ; 23: 101846, 2019.
Article in English | MEDLINE | ID: mdl-31077984

ABSTRACT

BACKGROUND: amyloid-PET reading has been classically implemented as a binary assessment, although the clinical experience has shown that the number of borderline cases is non negligible not only in epidemiological studies of asymptomatic subjects but also in naturalistic groups of symptomatic patients attending memory clinics. In this work we develop a model to compare and integrate visual reading with two independent semi-quantification methods in order to obtain a tracer-independent multi-parametric evaluation. METHODS: We retrospectively enrolled three cohorts of cognitively impaired patients submitted to 18F-florbetaben (53 subjects), 18F-flutemetamol (62 subjects), 18F-florbetapir (60 subjects) PET/CT respectively, in 6 European centres belonging to the EADC. The 175 scans were visually classified as positive/negative following approved criteria and further classified with a 5-step grading as negative, mild negative, borderline, mild positive, positive by 5 independent readers, blind to clinical data. Scan quality was also visually assessed and recorded. Semi-quantification was based on two quantifiers: the standardized uptake value (SUVr) and the ELBA method. We used a sigmoid model to relate the grading with the quantifiers. We measured the readers accord and inconsistencies in the visual assessment as well as the relationship between discrepancies on the grading and semi-quantifications. CONCLUSION: It is possible to construct a map between different tracers and different quantification methods without resorting to ad-hoc acquired cases. We used a 5-level visual scale which, together with a mathematical model, delivered cut-offs and transition regions on tracers that are (largely) independent from the population. All fluorinated tracers appeared to have the same contrast and discrimination ability with respect to the negative-to-positive grading. We validated the integration of both visual reading and different quantifiers in a more robust framework thus bridging the gap between a binary and a user-independent continuous scale.


Subject(s)
Alzheimer Disease/diagnostic imaging , Brain/diagnostic imaging , Plaque, Amyloid/diagnostic imaging , Positron-Emission Tomography/methods , Adult , Aged , Aged, 80 and over , Alzheimer Disease/epidemiology , Alzheimer Disease/metabolism , Brain/metabolism , Cohort Studies , Europe/epidemiology , Female , Fluorine Radioisotopes/metabolism , Humans , Male , Middle Aged , Plaque, Amyloid/metabolism , Positron-Emission Tomography/trends , Retrospective Studies
2.
Radiologe ; 58(3): 226-232, 2018 Mar.
Article in German | MEDLINE | ID: mdl-29344704

ABSTRACT

Prostate-specific membrane antigen (PSMA) positron emission tomography-computed tomography (PET-CT) imaging for the localization of prostate cancer is increasingly available in Germany. The advances and limitations in different disease stages are reviewed. As the clinical relevance of oligometastatic disease in primary cancer detected by PSMA PET-CT imaging is not yet completely understood, it should only be used in clinical trials. In recurrent prostate cancer after therapy with curative intent, PSMA PET-CT shows encouraging potential for the planning of salvage therapy. In metastatic castration-resistant prostate cancer evidence for its use is not available.


Subject(s)
Positron Emission Tomography Computed Tomography , Prostatic Neoplasms , Germany , Humans , Male , Neoplasm Recurrence, Local , Prostate-Specific Antigen , Prostatic Neoplasms/diagnostic imaging
3.
Urologe A ; 56(11): 1410-1416, 2017 Nov.
Article in German | MEDLINE | ID: mdl-28980045

ABSTRACT

Prostate-specific membrane antigen (PSMA) positron emission tomography-computed tomography (PET-CT) imaging for the localization of prostate cancer is increasingly available in Germany. The advances and limitations in different disease stages are reviewed. As the clinical relevance of oligometastatic disease in primary cancer detected by PSMA PET-CT imaging is not yet completely understood, it should only be used in clinical trials. In recurrent prostate cancer after therapy with curative intent, PSMA PET-CT shows encouraging potential for the planning of salvage therapy. In metastatic castration-resistant prostate cancer evidence for its use is not available.


Subject(s)
Antigens, Surface/analysis , Glutamate Carboxypeptidase II/analysis , Positron Emission Tomography Computed Tomography/methods , Prostatic Neoplasms/diagnostic imaging , Prostatic Neoplasms/pathology , Disease Progression , Humans , Male , Neoplasm Invasiveness , Neoplasm Recurrence, Local/diagnostic imaging , Neoplasm Recurrence, Local/pathology , Neoplasm Recurrence, Local/therapy , Neoplasm Staging , Prognosis , Prostatic Neoplasms/therapy , Prostatic Neoplasms, Castration-Resistant/diagnostic imaging , Prostatic Neoplasms, Castration-Resistant/pathology , Prostatic Neoplasms, Castration-Resistant/therapy , Salvage Therapy
4.
Radiologe ; 53(1): 75-82; quiz 83-4, 2013 Jan.
Article in German | MEDLINE | ID: mdl-23338250

ABSTRACT

In spite of a growing number of radiological scans in pregnant women there is still a high level of uncertainty concerning radiation exposure to the fetus. At the same time, the risk of fetal radiation injury is frequently overestimated. This entails an avoidable fear in the pregnant patient and may delay urgently required imaging and thus lead to an increased risk for maternal and fetal health. As a consequence, radiological scans in pregnant patients do not only require a thorough medical check but also a careful estimate of the specific radiation exposure to the fetus. The previous first part of the article described the legal requirements in Germany, the technical exposure and pharmacological risks for the pregnant woman and the fetus. The current second article focuses on the risk analysis for examinations with ionizing radiation and will provide recommendations for typical indications for maternal and fetal imaging.


Subject(s)
Diagnostic Imaging/methods , Pregnancy Complications/diagnostic imaging , Prenatal Exposure Delayed Effects/prevention & control , Radiation Injuries/prevention & control , Radiation Protection/methods , Radiometry/methods , Diagnostic Imaging/adverse effects , Female , Humans , Pregnancy , Prenatal Exposure Delayed Effects/etiology , Radiation Dosage , Radiation Injuries/etiology , Radiography
5.
Radiologe ; 52(1): 81-90; quiz 91-2, 2012 Jan.
Article in German | MEDLINE | ID: mdl-22249705

ABSTRACT

In a radiology department there are frequently asked questions associated with pregnant and breast feeding women. These are related to either pregnant patients or staff members or the questions are centered on the fetus as a patient. For pregnant patients the potential exposure to the mother and the fetus related to the imaging modality selected as well as the effects of the necessary contrast media must be taken into account. Even for methods without ionizing radiation possible limitations in the use for pregnant women must be discussed. Finally, this medical check defines the imaging modality and the necessary protocol and contrast media. The present article describes the legal requirements in Germany, the technical exposure and pharmacological risks for the pregnant woman and the fetus regarding imaging modalities with and without ionizing radiation. The forthcoming second article will address the risk analysis for examinations with ionizing radiation and will present recommendations for typical clinical imaging problems.


Subject(s)
Prenatal Diagnosis/adverse effects , Prenatal Exposure Delayed Effects/etiology , Prenatal Exposure Delayed Effects/prevention & control , Radiation Injuries/prevention & control , Radiation Protection/methods , Radiography/adverse effects , Female , Humans , Pregnancy , Radiation Injuries/etiology
6.
Eur J Radiol ; 81(5): 1076-82, 2012 May.
Article in English | MEDLINE | ID: mdl-21458944

ABSTRACT

INTRODUCTION: The lung-to-head ratio (LHR), measured by ultrasound, and the fetal lung volume (FLV), measured by MRI, are both used to predict survival and need for extra corporeal membrane oxygenation (ECMO) in infants with congenital diaphragmatic hernia (CDH). The aim of this study is to determine whether MRI measurements of the FLV, in addition to standard ultrasound measurements of the LHR, give better prediction of chronic lung disease, mortality by day 28 and need for ECMO. MATERIALS AND METHODS: Patients with unilateral isolated CDH born between January 2002 and December 2008 were eligible for inclusion. LHR and FLV were expressed as observed-to-expected values (O/E LHR and O/E FLV). Univariate and multivariate analyses were performed. Receiver operating characteristic curves were constructed and areas under the curve (AUC) were calculated to determine predictive values. RESULTS: 90 patients were included in the analysis. Combined measurement of the O/E LHR and O/E FLV gave a slightly better prediction of chronic lung disease (AUC=0.83 and AUC=0.87) and need for ECMO therapy (AUC=0.77 and AUC=0.81) than standard ultrasound measurements of the O/E LHR alone. Combined measurement of the O/E LHR and O/E FLV did not improve prediction of early mortality (AUC=0.90) compared to measurement of the O/E LHR alone (AUC=0.89). An intrathoracal position of the liver was independently associated with a higher risk of early mortality (p<0.001), chronic lung disease (p=0.007) and need for ECMO therapy (p=0.001). DISCUSSION: Chronic lung disease and need for ECMO therapy are slightly better predicted by combined measurement of the O/E LHR and the O/E FLV. Early mortality is very well predicted by measurement of the O/E LHR alone. CONCLUSION: Clinical relevance of additional MRI measurements may be debated.


Subject(s)
Extracorporeal Membrane Oxygenation/mortality , Hernias, Diaphragmatic, Congenital , Lung Injury/mortality , Lung Injury/therapy , Prenatal Diagnosis/statistics & numerical data , Comorbidity , Germany/epidemiology , Hernia, Diaphragmatic/mortality , Hernia, Diaphragmatic/therapy , Humans , Infant, Newborn , Lung Injury/congenital , Lung Injury/diagnosis , Prevalence , Prognosis , Reproducibility of Results , Risk Assessment , Risk Factors , Sensitivity and Specificity , Survival Analysis , Survival Rate , Treatment Outcome
7.
Klin Padiatr ; 221(5): 295-301, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19707992

ABSTRACT

BACKGROUND: Despite the ultrasound (US) based lung-to-head ratio (LHR) and first results of fetal lung volume (FLV) determination in magnetic resonance imaging (MRI), there is no reliable prenatal parameter for the clinical course and outcome of fetuses with congenital diaphragmatic hernia (CDH), in particular for the need of extracorporeal membrane oxygenation (ECMO). PATIENTS AND METHOD: MR FLV measurement was evaluated in 36 fetuses with CDH using T2-weighted half-Fourier acquisition single-shot turbo spin echo (HASTE) imaging. FLV and liver herniation, respectively, were correlated with survival and the need for ECMO therapy. A total of 18 healthy fetuses served as controls. MR FLV measurement was applied to predict survival and the need for neonatal ECMO therapy and to assess liver herniation as a prognostic parameter. RESULTS: On MRI there was a highly significant correlation of the FLV and patients' survival (p=0.0001) and ECMO requirement, respectively (p=0.0029). Compared to normal controls mean FLV in infants who died was 10% (9.4+/-5.8 ml) and 32% in surviving infants (25+/-9.7 ml). Liver herniation significantly decreased lung volume and negatively impacted clinical outcome (p<0.0005). CONCLUSION: The MR FLV is a strong predictor of survival in CDH patients. MR FLV measurements are also valuable to identify patients who may benefit from ECMO therapy. Upward liver herniation is the most important additional prognostic parameter.


Subject(s)
Hernia, Diaphragmatic/diagnosis , Hernias, Diaphragmatic, Congenital , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Lung Volume Measurements/methods , Lung/abnormalities , Magnetic Resonance Imaging/methods , Prenatal Diagnosis/methods , Abnormalities, Multiple/diagnosis , Extracorporeal Membrane Oxygenation , Female , Fourier Analysis , Hernia, Diaphragmatic/mortality , Hernia, Diaphragmatic/therapy , Humans , Infant , Infant, Newborn , Liver/embryology , Lung/pathology , Male , Organ Size/physiology , Oxygen/blood , Pregnancy , Pregnancy Trimester, Third , Prognosis , Reference Values , Risk Factors , Sensitivity and Specificity , Statistics as Topic , Survival Rate , Ultrasonography, Prenatal
8.
Orthopade ; 38(8): 752-4, 2009 Aug.
Article in German | MEDLINE | ID: mdl-19533085

ABSTRACT

Joint pain is one of the major symptoms in early leukemia. We report on a 16-year-old girl who presented with groin pain and an osteolytic bone lesion. Acute lymphoblastic leukemia was diagnosed, but the laboratory workup and radiologic imaging revealed atypical results. Particularly in early precursor B-cell acute lymphoblastic leukemia, comparable initial symptoms and signs have been reported in adolescents; therefore, we recommend performing a bone marrow aspiration early on in cases of suspected osteolytic bone lesions.


Subject(s)
Hypercalcemia/complications , Hypercalcemia/diagnosis , Osteolysis/complications , Osteolysis/diagnosis , Precursor Cell Lymphoblastic Leukemia-Lymphoma/complications , Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Adolescent , Blast Crisis/complications , Blast Crisis/diagnosis , Diagnosis, Differential , Female , Humans
9.
Sportverletz Sportschaden ; 22(3): 146-52, 2008 Sep.
Article in German | MEDLINE | ID: mdl-18814056

ABSTRACT

INTRODUCTION: The goal of this work was to assess the accuracy of the MR-Arthrografie in the evaluation of over head athletes injuries in comparison with athroscopy. MATERIAL AND METHODS: In 29 patients (middle age: 30 years, 21 male, 8 female, age 16 - 53 years) with persistent pain after conservative therapy an Arthro-MRI with intraarticular application of gadolinum was performed prior to arthroscopic surgery. The MRI was retrospectivly analysed of three examiners independently from one another. The result were compared to the results of the Arthroscopy. Interrater Reliability was calculated by using of Cohens Kappa. RESULTS: The MR-Arthrography could demonstrate 8 of 9 (88.9 %) partial tears of he rotator cuff. All SLAP (Superiores Labrum from Anterior to Posterior) Lesions as well as all bankart type Lesions were recognized through the MR-Arthrography. However, dependent upon the experience of the examiner in a span between 33.3 % (fellow radiologist) and 93.3 % (consultant radiologist). We found a high agreement between consultant radiologist and shoulder surgeon with Kappa of 0.79 for rotator cuff tear-, 0.86 for Bankart- and 0.82 for SLAP-Läsionen.


Subject(s)
Arthrography/methods , Arthroscopy/methods , Athletic Injuries/diagnosis , Magnetic Resonance Imaging/methods , Shoulder Dislocation/diagnosis , Shoulder Injuries , Shoulder Joint/pathology , Adolescent , Adult , Female , Humans , Male , Middle Aged , Reproducibility of Results , Sensitivity and Specificity
10.
Radiologe ; 46(2): 128-32, 2006 Feb.
Article in German | MEDLINE | ID: mdl-16362378

ABSTRACT

Ultrasonography is the primary imaging modality for the evaluation of fetal or maternal anomalies. This method is safe, relatively inexpensive, easily accessible, and allows real-time imaging. Continuous technical improvements in ultrasonography in the last 10-15 years have led to improved diagnostic accuracy for fetal malformations. In cases of complex anomalies magnetic resonance imaging (MRI) can provide additional information. MRI has evolved as a valuable diagnostic method for evaluating fetal pathology. Particularly with regard to similarity of liver and lung parenchyma in ultrasonography, diagnosis of congenital diaphragmatic hernia (CDH) can be difficult. Beside morphological aspects, e.g., herniation of abdominal contents into the chest, small amounts of compressed lung can be visualized on MRI. The feasibility of using volumetric measurement on MRI may be helpful to predict high-risk fetuses and facilitate decisions to assure adequate prenatal and postnatal management to improve postnatal outcome.


Subject(s)
Hernia, Diaphragmatic/diagnosis , Hernias, Diaphragmatic, Congenital , Image Enhancement/methods , Imaging, Three-Dimensional/methods , Magnetic Resonance Imaging/methods , Prenatal Diagnosis/methods , Humans , Practice Guidelines as Topic , Practice Patterns, Physicians'
11.
Radiologe ; 46(2): 133-8, 2006 Feb.
Article in German | MEDLINE | ID: mdl-16369825

ABSTRACT

Despite advancing therapeutic strategies, congenital cystadenomatoid malformation of the fetal lung is still a potentially life-threatening anomaly. Antenatally, the development of hydrops as well as the natural history of the malformation is of particular therapeutic and prognostic importance. Postnatally, respiratory distress due to pulmonary hypoplasia counts as a crucial limiting factor. Owing to its feasibility and practicability, as well as a high sensitivity, antenatal ultrasound is still the screening method of choice for the detection of fetal thoracic malformations. However, particularly in cases of indistinguishable sonographic findings, fetal MRI is the modality of choice for proving the diagnosis and preliminary appraisal of intensive care therapy and extracorporal membrane oxygenation postnatally. Furthermore, fetal MRI often facilitates assessment and planning of intrauterine surgical procedures. These two features frequently require a close transfer to an expert neonatal centre.


Subject(s)
Cystic Adenomatoid Malformation of Lung, Congenital/diagnosis , Image Enhancement/methods , Magnetic Resonance Imaging/methods , Prenatal Diagnosis/methods , Humans , Practice Guidelines as Topic , Practice Patterns, Physicians' , Prognosis
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