The Assessment of Early Stage Computed Tomography Findings in Acute Ischemic Stroke

Öz

The imaging techniques have become important tools during diagnostic stage of acute ischemic stroke during the last 30 years. The improvement in these techniques further increased the clinical areas that these tools could be used. As computerized brain tomography (CT) is a rapid, cheap, non-invasive and highly available imaging tool in most hospitals, it remains to be the primary scanning method for all acute patients. The aim of this study was to evaluate the early stage CT findings in the ischemic stroke patients which have been scanned in the first 8 to 12 hours after the incidence. Sixty four cases (26 male, 38 female) who had clinical symptoms of ischemic stroke have been included in this study. CT scan was performed twice to these patients; first in the first 8 to 12 hours, and second in between 24 hours and 48 hours after the stroke. The middle cerebral artery perfused area was the most common arterial area affected among cases who had CT findings in early scans. Hypodense lesions were most common lesions encountered in CT findings. Hyperdense middle cerebral artery sign in early CT findings could be an indicator of ischemia due to arterial occlusion. We determined that the CT images obtained at the beginning of developing stroke appeared to show the lesions smaller than what they really were. There were significant differences between the emergency room evaluation and detailed clinical evaluation of CT scans. More findings have been observed in late CT scans performed between 24 hours and 48 hours than the ones performed in the first 8 hours and 12 hours. There was no correlation between the presence of CT findings in early scans and severity of clinical features of ischemia. CT appears to be an important tool in diagnosing ischemic strokes even at early stages. Developments in diagnostic precision of CT tools will further increase our understanding of ischemic strokes and their clinical progress.

Anahtar Kelimeler

• Ischemic Stroke, Computed Brain Tomography, Early Stage

Akut İskemik Strokta Beyin Tomografisi Erken Bulgularının Değerlendirilmesi

Öz

Son 30 yılda gelişen görüntüleme yöntemleri akut iskemik strokta sadece tanı sürecini değil, uygulanacak tıbbi ve girişimsel müdahaleleri de yönlendirmektedir. Strok sonrası ilk 24 saatte beyin tomografisi (BT) halen daha hızlı, daha ucuz, non invaziv ve tüm hastalar için kolay ulaşılabilir olması nedeniyle primer tarama yöntemi olmayı sürdürmektedir. Bu çalışmada Nöroloji kliniğine başvuran iskemik strok olgularının erken evre BT bulgularının saptanması ve bu bulgular ile çeşitli klinik ve demografik veriler arasındaki ilişkinin araştırılması amaçlanmıştır. Bu çalışmaya iskemik strok tanısı almış 26' sı erkek, 38' i kadın toplam 64 olgu dahil edilmiştir. Olguların strok sonrası ilk 8-12 saatte ve 24-48. saatler arasında olmak üzere toplam iki BT incelemesi yapılmıştır. Çalışma sonucunda erken BT bulgusu veren olgularda, orta serebral arter alan tutulumunun daha çok görüldüğü saptanmıştır. Erken BT bulguları arasında görülen orta serebral arter hiperdansitesinin arteriyel oklüzyona uyan iskeminin bir habercisi olabileceği düşünülmüştür. Başlangıçta saptanan anormal BT bulgularının, ilerlemekte olan infarktın büyüklüğünü olduğundan daha az gösterdiği belirlenmiştir. Ayrıca erken BT bulgularının acil şartlarda değerlendirilmesi ile ayrıntılı değerlendirilmesi arasında belirgin bir farklılık mevcuttur. İskeminin erken BT bulguları, iskemik strokun ilk saatlerinde bile görülebilir. Erken BT bulgularının tanımlanması düzenli eğitim ve gelişen BT teknolojisi izlenerek geliştirilmelidir.

Anahtar Kelimeler

• İskemik Strok, Beyin Tomografisi, Erken Evre

Kaynakça

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