The salvageable brain in acute ischemic stroke. The concept of a reverse mismatch: a mini-review.
Karaszewski Bartosz,Jabłoński Bartosz,Żukowicz Wioletta
Metabolic brain disease
Recent studies have opened a new era in treatment of acute ischemic stroke, enabling thrombolysis or thrombectomy far beyond the standard therapeutic "time windows". These therapeutic protocols are built on various combinations of perfusion parameters, lesion volume, and neurological assessment. However, on top of the brain perfusion, there are other multiple factors that might modify the probability of neuronal apoptosis and necrosis following focal cerebral ischemia. We hypothesize that a diagnostic approach with measurements of selected biochemical parameters in the brain, in addition to those based solely on perfusion or MR diffusion, might allow for more personalized management protocols. Moreover, some local processes in the brain, triggered by acute ischemia or its consequences other than hypoperfusion directly, like, for example, excitotoxicity, might lead to apoptosis of the cells in the brain localized also beyond the area of hypoperfusion. This phenomenon might be responsible for the expansion of the brain damage much beyond the initial perfusion deficit or beyond the initial diffusion (DWI) restriction area, reported for example in T2W or FLAIR MRI in some stroke patients who have no other reasons to deteriorate (a reverse DWI - T2W / FLAIR, a reverse perfusion - DWI, or a reverse DWI - DWI mismatch).
Neurovascular Unit as a Source of Ischemic Stroke Biomarkers-Limitations of Experimental Studies and Perspectives for Clinical Application.
Steliga Aleksandra,Kowiański Przemysław,Czuba Ewelina,Waśkow Monika,Moryś Janusz,Lietzau Grażyna
Translational stroke research
Cerebral stroke, which is one of the most frequent causes of mortality and leading cause of disability in developed countries, often leads to devastating and irreversible brain damage. Neurological and neuroradiological diagnosis of stroke, especially in its acute phase, is frequently uncertain or inconclusive. This results in difficulties in identification of patients with poor prognosis or being at high risk for complications. It also makes difficult identification of these stroke patients who could benefit from more aggressive therapies. In contrary to the cardiovascular disease, no single biomarker is available for the ischemic stroke, addressing the abovementioned issues. This justifies the need for identifying of effective diagnostic measures characterized by high specificity and sensitivity. One of the promising avenues in this area is studies on the panels of biomarkers characteristic for processes which occur in different types and phases of ischemic stroke and represent all morphological constituents of the brains' neurovascular unit (NVU). In this review, we present the current state of knowledge concerning already-used or potentially applicable biomarkers of the ischemic stroke. We also discuss the perspectives for identification of biomarkers representative for different types and phases of the ischemic stroke, as well as for different constituents of NVU, which concentration levels correlate with extent of brain damage and patients' neurological status. Finally, a critical analysis of perspectives on further improvement of the ischemic stroke diagnosis is presented.