Platelet glycoprotein IIb/IIIa inhibitors in acute ischemic stroke.

Acute ischemic stroke (AIS) is a common cause of morbidity and mortality worldwide. Thrombolytic therapy with tissue plasminogen activator, the only approved treatment for AIS, is received by less than 2% of patients. Moreover, there is a slight increase in hemorrhagic complications with thrombolysis. Therefore, there is a need for newer therapeutic modalities in AIS, which could be used in window periods beyond 3-6 h after stroke onset with fewer hemorrhagic complications. Glycoprotein IIb/IIIa inhibitors (GPI), after their initial success in patients with acute coronary syndromes, promised much in patients with AIS over the past decade or so. However, their exact role in patients with AIS, including the window periods and type of strokes, and the risk of symptomatic or asymptomatic hemorrhage are unclear at the moment. The current review focuses on the literature concerning the use of GPI in AIS and looks at the available evidence regarding their use. Abciximab thought to be safe and effective in initial case series and early trials, has not been shown to improve outcomes in AIS, and is associated with higher rates of hemorrhage. Tirofiban appears to be safe and effective in initial trials and there is a need to conduct further trials to establish its role in AIS.

Positron emission tomography in neurological diseases.

Positron emission tomography (PET) is the study of human physiology by electronic detection of positron-emitting radiopharmaceuticals. It is one of the noninvasive technologies that can measure the metabolic and functional activity of living tissue. Positron emission tomography finds its clinical applications in broadly three specialties--oncology, cardiology, and neurology. The current review focuses on its indications in neurological diseases. Recently published literature on the use of PET in neurology has been thoroughly analyzed. Several reports regarding the usage of PET in epilepsy, stroke, dementia, and movement disorders are available. Positron emission tomography does not appear to be useful as a primary or sole imaging technique in these conditions. On the other hand, it is useful in very specific situations, which have been elaborated in the review. It is also noteworthy that PET is complementary to the computed tomography/magnetic resonance imaging findings and data obtained from combining these modalities can be valuable in situations such as localization of the epileptogenic focus in cases of refractory epilepsy or for prediction of the outcome after thrombolysis in acute ischemic stroke. The major handicaps in widespread use of PET appear to be its lack of availability and its relatively high cost. Nevertheless, a review such as this would be helpful in judiciously selecting those patients who would benefit from undergoing a PET scan, at a time when PET imaging facility is likely to be available soon in the Indian private sector.