In this study of patients suffering an aneurysmal subarachnoid hemorrhage (SAH) we would like to investigate the pathophysiological mechanisms that lead to the phenomenon delayed cerebral ischemia (DCI).~We will accomplish this through analyzing the profile of microRNA expression in the cerebrospinal fluid of SAH patients treated with extraventricular drainage.~At first we wish to compare the expression of 376 specific microRNA between 12 patients developing DCI (group 1) and 12 patients without DCI (group 2) in cerebrospinal fluid drawn on day 5 after ictus.~Secondly specific microRNAs of interest in which the expression differs between group 1 and 2 are analyzed daily to investigate the dynamic changes in expression and compared to the clinical course.~Should we find no differently expressed specific microRNAs we will compare the expression of microRNA in group 1+2 with group 3.~In addition, some of the patients as part of another clinical trial (NCT01447095~) will have established invasive neuromonitoring including microdialysis. It is our intention to develop a method for analyzing microRNA in this microdialysate.~DCI as defined by Vergouwen et al in Stroke 2010;41(10):2391-2395:~The occurrence of focal neurological impairment (such as hemiparesis, aphasia, apraxia, hemianopia, or neglect), or a decrease of at least 2 points on the Glasgow Coma Scale (either on the total score or on one of its individual components [eye, motor on either side, verbal]). This should last for at least 1 hour, is not apparent immediately after aneurysm occlusion, and cannot be attributed to other causes by means of clinical assessment, CT or MRI scanning of the brain, and appropriate laboratory studies.
The purpose of this study is to compare the profile of microRNA in cerebrospinal fluid from patients suffering subarachnoid hemorrhage with and without delayed cerebral ischemia.