Background.- The aim of the study was to see whether the serum neuron specific enolase (NSE) levels, as a noninvasive technique could be utilized to determine the morbidity at early stage after acute ischemic stroke.Design.- In the present study, 40 patients with acute ischemic stroke and 20 ages and gender matched volunteer were investigated. Serum NSE levels at 48th hours, fifth days, and tenth days were analyzed and simultaneous clinical status according to Scandinavian stroke scale was examined and infarct volumes at 48th hours were measured.Results and Conclusion.- There was a statistically significant difference in serum NSE values at 48th hours and fifth days of whole patient group (22,51±7.05 ng/ml, 13,1±4,76 ng/ml, respectively) compared to those of control group (8.54±2,58 ng/ml), ( p<0.001, p<0.01, respectively). However there was no statistically significant difference between the patients and controls at 10 days (p<0.01). So, it was thought that NSE had 94% sensitivity and 80% specifity for acute ischemic stroke. There were positive correlation among NSE levels and infarct volumes, and negative correlation among NSE levels and clinical status.     Nöron-spesifik enolaz (NSE), beyin için özgül proteinlerden biri olup, gilikolitik yolda 2- fosfogliseratın fosfoenolpurivata dönüşümünü katalize eden enolaz enziminin bir izoenzimidir. NSE nöronlar ve nöroendokrin hücrelerde yüksek oranlarda mevcut olup beynin total çözülebilir proteininin %0.4-4’ünü oluşturur.1,2 İskemik stroklu hastalarda serebral nöronal hasarın ilk haftalarında serum NSE düzeylerinde artış olduğu gösterilmiş ve iskemik serebrovasküler hastalıklarda iskemik hasarın kantitatif bir belirleyicisi olarak kullanılabileceği iddia edilmiştir. 3-8 Bu çalışmanın amacı; akut iskemik stroklu hastalarda serum NSE düzeyi ile infarkt volümü ve klinik durum arasındaki korelasyonun gösterilmesi ve NSE’nin iskemik stroklu hastalarda erken bir prognostik belirleyici olup olamayacağının tartışılmasıdır.* Anahtar Kelimeler: İskemik strok, NSE, infarkt volümü, strok skalası* Key Words: Ischemic stroke, NSE, infarction volume, stroke scale