Neurovascular imaging

As there are numerous different MDCT-systems on the market, a multitude of optimized scanning protocols are available for neurovascular imaging depending on the respective systems. Sample protocols for NECT are provided in Table 10.1, while sample protocols for CTA are shown in Table 10.2 (Ertl-Wagner et al. 2004). 

Keywords Vasogenic edema Neurovascular unit teinases Aquaporins Blood-brain barrier Imaging... 

The story of MRI CAs began with X-ray CAs. DTPA (diethyltriaminepentaacetic acid) was widely used as a chelate for the detoxification and solubilization of bismuth, which is a metal ion in X-ray CAs [3], DTPA attracted the attention of scientist, who developed Gd-DTPA as the first paramagnetic complex in MRI clinical studies [4], It was initially applied to image the central nervous system (CNS). However, owing to its superior anatomical contrast enhancement, it was later applied to the imaging of cardiovascular and neurovascular systems, and in oncology [5],... 

The simplest contrast-timing strategy is the fixed delay from the time of contrast injection to imaging. With a 16-slice scanner, a fixed delay of 25 s usually yields adequate opacification of the neurovascular tree. However, patients with atrial fibrillation or other causes of decreased cardiac output require a longer delay (35-40 s). 

Fig. 13.6 The Solitaire device (ev3 Neurovascular, Inc), (a) Baseline angiogram demonstrates complete occlusion of the right MCA black arrow) and ACA white arrow), (b) Native images demonstrate the Solitaire device distal white arrow) and proximal black arrow) markers as well as the microcatheter tip arrowhead), (c) Angiogram performed with the Solitaire device in place demonstrates immediate partial reperfusion black arrow), (d) Roadmap angiogram obtained during retrieval of the...

Clinical Applications of Neurovascular MDCT 126 10.3.1 Comprehensive Stroke Imaging 126... 

In addition to the fast-paced innovations of new scanners, new developments in post processing with semi-automatic quantifications of stenoses or bone-removal techniques had a pronounced influence on current clinical routine (Anderson et al. 1999 Chappell et al. 2003). Modern neurovascular CTA as a non-invasive imaging modality is more and more replacing conventional diagnostic DSA (Fell et al. 2006 Tomandl et al. 2006 Hoh et al. 2004). 

There are numerous applications and indications for neurovascular MDCT. These include comprehensive stroke imaging, evaluation of the extra- and intracranial vasculature of head and neck, as well as preoperative therapy planning. In this chapter we wiU focus on the most commonly used and on more specialized, but highly relevant neurovascular MDCT applications. 

The lirst rib is probably the rib most commonly involved in somatic dysfunction of all the ribs. It is affected by trauma, stress, and posture as well as by dysfunction ofthe C7-T1 complex. The patient may report "shoulder" pain, stiff neck, upper back or neck pain, and an inability to turn the head while driving. The first rib can impinge the neurovascular bundle as it passes between it and the clavicle through the costoclavicular space. The anterior and middle scalene muscles, which raise the first rib, may likewise compress the brachial plexus when they are in spasm and result in thoracic outlet syndrome symptoms. The patient s symptoms are then described as pain, numbness, or paresthesias ofthe arm or hand on the involved side. The physician needs to be aware that this may cause confusion should the patient demonstrate a herniated cervical disc on magnetic resonance imaging [MRO. The symptoms may be caused by the rib dysfunction rather than the herniated disc, so evaluation ofthe rib for normal motion and treatment of any dysfunction should be performed in these cases. Osteopathic manipulation may save the patient unnecessary surgery. 

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