Clinical MR in the year 2010

This article tries to look into the future of magnetic resonance imaging. Deducing from six rules, it pinpoints the most likely developments of this imaging techniqu

MR perfusion imaging: correlation with PET and quantitative angiography

4. Conclusions: The presented MR approach reliably identifies patients with anatomically and hemodynamically signiticant coronary artery stenoses. This is due to the fact, that the pulse sequence used produces a substantial change in signal intensity in the perfused versus poorly perfused myocardial regions. Analysis of upslope in this setting rather than of other parameters provides a very sensitive and specific measure of myocardial ischemia. As upslope is a semiquantitative measure of absolute perfusion, even patients with triple vessel disease may be evaluated using this method. This is not the case when using conventional nuclear techniques. Furthermore, the spatial resolution of the MR images permits one to resolve the subendocardial layers of the myocardium, which thus can be evaluated separately from the entire wall. Again, this is not possible using nuclear cardiology perfusion imaging. The robustness of this MR perfusion imaging approach and the fact, that most of the heart can be covered may qualify for its clinical application in the management of coronary artery diseas

Integrating imaging modalities: what makes sense from a workflow perspective?

Purpose: From a workflow/cost perspective integrated imaging is not an obvious solution. An analysis of scanning costs as a function of system cost and relevant imaging times is presented. This analysis ignores potential clinical advantages of integrated imaging. Methods: An analysis comparing separate vs integrated imaging costs was performed by deriving pertinent equations and using reasonable cost numbers for imaging devices and systems, room and other variable costs. Integrated systems were divided into those sequentially and simultaneously. Sequential scanning can be done with two devices placed in a single or in two different scanning rooms. Graphs were derived which represent the cost difference between integrated imaging system options and their separate counterparts vs scanning time on one of the devices and cost ratio of an integrated system and its counterpart of separate devices. Results: Integrated systems are favoured by the fact that patients have to be up- and downloaded only once. If imaging times become longer than patient changing times, imaging on separate devices is advantageous. An integrated imaging cost advantage is achieved if the integrated systems typically and overall cost three fourths or less of the separate systems. If PET imaging takes 15 min or less, PET/CT imaging costs less than separate PET and CT imaging, while this time is below 5min for SPECT/CT. A two-room integrated system has the added advantage that patient download time is not cost relevant, when imaging times on the two devices differ by more than the patient download time. Conclusion: PET/CT scanning is a cost-effective implementation of an integrated system unlike most current SPECT/CT systems. Integration of two devices in two rooms by a shuttle seems the way how to make PET/MR cost-effective and may well also be a design option for SPECT/CT system

A look ahead: PET/MR versus PET/CT

Introduction: Integration of positron emission tomography (PET) and magnetic resonance (MR) has become a topic of increasing interest to the imaging community over the past two years. Objectives: In this text, the authors attempt to distinguish facts from fiction concerning such integrated systems. Analysis of existing information of combined imaging on existing brain PET/MR systems and imaging experience with PET-computed tomography (CT) is reviewed. Various types of system integration of PET and MR are discussed with completely independent systems on one hand and completely integrated systems with the possibility of simultaneous data acquisition on the other hand. Furthermore, it is discussed, what simultaneous data acquisition with nuclear imaging systems combined with MR or CT really means, as technical simultaneity may not be relevant in light of the pharmacokinetics of the nuclear tracers used. Discussion: The authors conclude that combining PET/MR is an interesting research endeavor with uncertain outcome. They argue that, while completely simultaneous brain applications are of research interest immediately, clinical applications do not currently warrant the construction of fully integrated systems. Systems adjacent to each other, where imaging tables are linked with a patient "shuttle” thereby requiring only patient translation but no repositioning, may be a good start to assess the value of integrated PET/M

Iatrogenic FDG foci in the lungs: a pitfall of PET image interpretation

Abstract.: 2-[F-18]-fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) has become an important staging modality for many tumors, including bronchial carcinoma; however it is important to know that there are several pitfalls in PET image interpretation. In this report we demonstrate three cases in which focal intrapulmonary FDG uptake could possibly represent iatrogenic microembolism. These FDG accumulations would have been interpreted as malignant tumor mass in the lung if no anatomic correlation would have been performed. For this reason, we further present an integrated PET/CT scanner, which recently has been introduced. This correlation of molecular and morphological information enables the specification of the FDG-PET finding

Schreibaby – warum, wieso, weshalb? : Prä-, peri- und postnatale Einflussfaktoren des exzessiven Säuglingsschreiens

Darstellung des Themas: Ein exzessiv schreiender Säugling kann die Eltern-Kind-Beziehung massiv belasten und in gewissen Fällen zu Kindsmisshandlungen führen. Einflussfaktoren auf das Phänomen „Schreibaby“ werden kontrovers diskutiert und Präventionsmassnahmen selten erläutert. Ziel: Es werden Einflussfaktoren des exzessiven Schreiens anhand aktueller Studien aufgezeigt. Anknüpfend daran werden Präventionsmassnahmen zur Vermeidung der Schreibabyproblematik abgeleitet. Hebammen sollen ihre Klientinnen während der Schwangerschaft, unter der Geburt und bis sechs Monate nach der Geburt zur Prävention des exzessiven Schreiens aufklären können, um die gesunde Entwicklung der Eltern-Kind-Beziehung zu fördern. Methode: Auf fünf Datenbanken werden mit definierten Keywords und festgelegten Ein- und Ausschlusskriterien fünf Studien recherchiert, welche anschliessend nach Katja Stahl (2008) beurteilt werden. Relevante Ergebnisse: Anhand der in dieser Bachelorarbeit beurteilten Studien beeinflussen psychische Belastungen, ein tiefer Vitamin B12-Blutwert in der Frühschwangerschaft, der Arbeitswiedereinstieg direkt nach dem bezahlten Mutterschaftsurlaub und die Nationalität das kindliche Schreiverhalten negativ. Schlussfolgerung: Die Einflussfaktoren auf das exzessive kindliche Schreien sind vielschichtig miteinander verbunden. Eltern mit Risikofaktoren sollen frühzeitig identifiziert und im Alltag präventiv unterstützt werden. Für die Sicherung einiger Ergebnisse ist weitere Forschung zu dieser Thematik und eine einheitliche Definition des Begriffs „Schreibaby“ notwendig