LOCALITE - A Frameless Neuronavigation System for Interventional Magnetic Resonance Imaging Systems

. LOCALITE is a frameless neuronavigation system that particularly addresses a problem with currentinterventional magnetic resonance imaging #iMRI# systems: non-interactive response time in the interactive scan mode and poor image quality with fast scanning sequences. LOCALITE calculates image planes selected via a handheld localizer from pre- or intra-operativevolume data sets. This approach provides a really interactive localizer device with high quality images. The volume data are generated after the patient has been broughtinto the operating room and #xed within the iMRI. Images are part of an enhanced reality scenario containing only the salient visual information for the intra-operative task rather than letting the surgeon drown in lots of images. First studies show that LOCALITE enables the surgeon to use the iMRI system intuitively and much faster. 1 Introduction With minimally invasiveinterventions, the surgeon's direct view is often extremely restricted. Recent ..

Inhalation of nitric oxide prevents ischemic brain damage in experimental stroke by selective dilatation of collateral arterioles

RATIONALE: Stroke is the third most common cause of death in industrialized countries. The main therapeutic target is the ischemic penumbra, potentially salvageable brain tissue that dies within the first few hours after blood flow cessation. Hence, strategies to keep the penumbra alive until reperfusion occurs are needed. OBJECTIVE:: To study the effect of inhaled nitric oxide on cerebral vessels and cerebral perfusion under physiological conditions and in different models of cerebral ischemia. METHODS AND RESULTS:: This experimental study demonstrates that inhaled nitric oxide (applied in 30% oxygen/70% air mixture) leads to the formation of nitric oxide carriers in blood that distribute throughout the body. This was ascertained by in vivo microscopy in adult mice. Although under normal conditions inhaled nitric oxide does not affect cerebral blood flow, after experimental cerebral ischemia induced by transient middle cerebral artery occlusion it selectively dilates arterioles in the ischemic penumbra, thereby increasing collateral blood flow and significantly reducing ischemic brain damage. This translates into significantly improved neurological outcome. These findings were validated in independent laboratories using two different mouse models of cerebral ischemia and in a clinically relevant large animal model of stroke. CONCLUSIONS:: Inhaled nitric oxide thus may provide a completely novel strategy to improve penumbral blood flow and neuronal survival in stroke or other ischemic conditions