Intravascular Inflammation Triggers Intracerebral Activated Microglia and Contributes to Secondary Brain Injury After Experimental Subarachnoid Hemorrhage (eSAH).

Activation of innate immunity contributes to secondary brain injury after experimental subarachnoid hemorrhage (eSAH). Microglia accumulation and activation within the brain has recently been shown to induce neuronal cell death after eSAH. In isolated mouse brain capillaries after eSAH, we show a significantly increased gene expression for intercellular adhesion molecule-1 (ICAM-1) and P-selectin.

Microglia inflict delayed brain injury after subarachnoid hemorrhage.

Inflammatory changes have been postulated to contribute to secondary brain injury after aneurysmal subarachnoid hemorrhage (SAH). In human specimens after SAH as well as in experimental SAH using mice, we show an intracerebral accumulation of inflammatory cells between days 4 and 28 after the bleeding. Using bone marrow chimeric mice allowing tracing of all peripherally derived immune cells, we confirm a truly CNS-intrinsic, microglial origin of these immune cells, exhibiting an inflammatory state, and rule out invasion of myeloid cells from the periphery into the brain.

Mouse cerebral magnetic resonance imaging fails to visualize brain volume changes after experimental subarachnoid hemorrhage.

Background: Brain atrophy after subarachnoid hemorrhage (SAH) has been detected in humans and might serve as a functional read-out parameter for neuropsychological deficits. To determine whether serial magnetic resonance imaging (MRI) can provide information on brain atrophy in animals as well, mice that had undergone experimental SAH were scanned repeatedly after the bleeding.

Methods: Using a 7-T rodent MRI, six mice were evaluated for total hemispheric, cerebrospinal fluid (CSF) and hippocampal volumes on days 1, 2, 4, 21, 28, 42 and 60 after experimental SAH or sham operation, respectively.

Catheter placement for lysis of spontaneous intracerebral hematomas: is a navigated stylet better than pointer-guided frameless stereotaxy for intrahematomal catheter positioning?

The optimal management of spontaneous intracerebral hemorrhage (ICH), especially if deep-seated, remains a matter of discussion. Lysis of the blood clot applying recombinant tissue-type plasminogen activator (rtPA) by an intrahematomal catheter is a minimally invasive treatment option, currently being under investigation in a randomized trial. The center position of the catheter in the hematoma is believed to be crucial for an optimal clot lysis.