Presented is a novel MR imaging protocol to comprehensively assess vessel lumen and hemodynamics of the cerebrospinal veins. The 3 station exam is designed to cover middle cerebral, jugular, and azygous veins in order to investigate the CCSVI hypothesis for the association of insufficient venous return with multiple sclerosis.
Background
Recently, Zamboni et al. have postulated that chronic cerebrospinal venous insufficiency (CCSVI) with reflux to the level of the deep cerebrospinal veins precipitates increased iron deposition and a neuroinflammatory cascade of events that ultimately result in Multiple Sclerosis (MS) (1). He proposed 5 ultrasound (US) based criteria of diameter changes and impaired flow in the cerebrospinal veins to diagnose MS (2), some of which are hard to assess because they require special US hardware and technologist training and US measures are known to be user-dependent. Here we describe our initial experience with a 4D MR Flow approach, PC-VIPR (3), to overcome these problems with a user-independent, non-invasive technique that provides whole vessel coverage.
Anzeige
Methods
To investigate vessel anatomy and hemodynamics, 7 healthy volunteers were imaged on a clinical 3T system (750 Discovery, GE Healthcare). PC-VIPR of the cerebral, internal jugular (IJV), and azygous veins were performed in a three station exam with a neurovascular phased array and a cardiac coil. Sample imaging parameters for cerebral veins are: Dual Echo, FOV: 24 x 24 x 16 cm, Res: 0.6 x 0.6 x 0.6 mm, 9000 Projections (36x), TR=15.9, BW = 31.25, VENC = 40 cm/s, 7:30 min scan time. Acquisitions were modified to allow for retrospective cardiac gating, with additional modifications being investigated for retrospective double-gated cardiac and respiratory reconstruction to address phasic changes in venous flow due to respiration. A single injection of gadofosveset trisodium (Ablavar, Lantheus Medical Imaging, 0.03-0.05 mmol/kg at 3 ml/s) was used for a first pass perfusion scan, contrast-enhanced MRA, and the PC-VIPR scans.
Results
Figure 1 shows representative results in the cerebral veins. PC-VIPR allows whole head coverage with high isotropic spatial resolution and visualization of flow characteristics can be collected with retrospective selection of vessels of interest in an arbitrary orientation. Example flow visualizations from the three PC-VIPR sequences are shown in Figure 2. Measurement planes are placed orthogonally to the IJV, from which reflux over the cardiac cycle can be easily detected and quantified.
×
×
Conclusions
This feasibility study demonstrates the potential for 4D MR flow acquisitions to noninvasively measure and visualize vessel anatomy and velocity fields in the cerebrospinal veins. The use of PC VIPR provides hemodynamic information over a large vascular territory, thereby greatly simplifying scan prescription and providing more complete information along vessel paths as compared to multiple 2D PC acquisitions.
This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Extreme Arbeitsverdichtung und kaum Supervision: Dr. Andrea Martini, Sprecherin des Bündnisses Junge Ärztinnen und Ärzte (BJÄ) über den Frust des ärztlichen Nachwuchses und die Vorteile des Rucksack-Modells.
Darauf haben viele Praxen gewartet: Das Zi hat eine Liste von Praxisverwaltungssystemen veröffentlicht, die von Nutzern positiv bewertet werden. Eine gute Grundlage für wechselwillige Ärztinnen und Psychotherapeuten.
Akuter Schwindel stellt oft eine diagnostische Herausforderung dar. Wie nützlich dabei eine MRT ist, hat eine Studie aus Finnland untersucht. Immerhin einer von sechs Patienten wurde mit akutem ischämischem Schlaganfall diagnostiziert.
Routinemäßige Mammografien helfen, Brustkrebs frühzeitig zu erkennen. Anhand der Röntgenuntersuchung lassen sich aber auch kardiovaskuläre Risikopatientinnen identifizieren. Als zuverlässiger Anhaltspunkt gilt die Verkalkung der Brustarterien.
Update Radiologie
Bestellen Sie unseren Fach-Newsletterund bleiben Sie gut informiert.