Nebehat TAŞDEMİR, Yusuf TAMAM, Veysi TABAK, Andaç DEDEOĞLU

Akut iskemik strokta beyin tomografisi erken bulgularının değerlendirilmesi

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.

The assessment of early stage computed tomography findings in acute ıschemic stroke

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.

PDF

___

1. Stegmayr B, Asplund K, Kuulasmaa K, et all. Stroke incidence and mortality correlated to stroke risk factors in WHO MONICA Project: an ecological study of 18 populations. Stroke, 1997; 28:1367-1374
2. The national institute of Neurological Disordes and stroke, rt. PA stroke study group. Tissue plasminogen activator for acute stroke. N Eng J Med 1995;335:1581-1587
3. Şener U, Kus N.S, Zorlu Y, Önal N, ALTINEL O. Akut İskemik İnmelerde Erken Evre Bilgisayarlı Beyin Tomografi Bulguları. Türk Serebrovasküler Hastalıklar Dergisi 2004 10:3; 111-116,
4. Moulin T, Cattin F, Craepin-Leblond T, et all. Early CT signs in acute middle cerebral artery infarction: predictive value for subsequent infarct locations and outcome. Neurology. 1996;47:366-375.
5. Marks MP, Holmgren EB, Fox AJ, et all. Evaluation of early computed tomographic findings in acute ischemic stroke. Stroke. 1999;30:389-392.
6. Büttner T, Uffmann M, Güneş N, Köster O. Early CCT signs of supratentorial brain infarction: clinico-radiological correlations. Acta Neurol. Scand. 1997;96:317-323.
7. Von Kummer R, Meyding-Lamade U, Forsting M, et all. Sensitivity and prognostic value of early Computed tomography in middle cerebral artery trunk occlusion. AJNR Am J Neuroradiol 1994:15: 9-15.
8. Von Kummer R, BozzaL, Marelf. Early CT diagnosis of hemispheric brain infarction. Berlin: Springer, 1995.
9. Betz AL, Iannotti F, Hoff JT. Brain edema: a classification based on blood-brain barrier integrity. Cerebrovasc Brain Metab Rev. 1989;1:133-154.
10. Wall SD, Brant-Zawatzki M, Jeffrey RB, Bornes B. High freguency CT findings within 24 hours ofter cerebral infarction. AJR Am J Neuroradiol 1982; 138: 307-311.
11. Inoue Y, Yakomoto K, Miyamoto T, et all. Sequential Computed tomography scans in acute cerebral infarction. Radiology 1980; 135: 655-662.
12. Gacs G, Fox AJ, Barnett HJM, Vinuela F. CT visualization of intrakranial arterial tromboembolism. Stroke 1983; 14: 756-762.
13. Schuierer G, Huk W. The unilateral hipodense middle cerebral artery, an early CT- sign of embolism on thrombosis. Neuroradiology 1998; 30: 120-122
14. Granstrom P. CT visualization of thrombus in cerebral artery. J Comput Asist Tomography. 1986; 10: 541-542.
15. Lounes J, Ketonen 1. Dense middle cerebral artery sign: an indicator of poor outcome in middle cerebral artery infarction. J Neurol Neurosurg Psychiatry 1987:50:1550- 1552.
16. Tomsick TA, Brott TG, Chambers AA, et al. Hyperdense midle cerebral artery sign on CT: efficacy in detecting middle cerebral artery thrombosis. AJNR Am J Neuroradiol 1990;11: 473-477.
17. Brott T, Marlor JR, Olinger CP, et al. Measurements of acute cerebral infarction: lesion size by computed tomography. Stroke 1989; 20: 871-875.
18. Tomsick T, Brott T, Borsen W, et all. Thrombus localization with emergency cerebral CT. AJNR Am J Neuroradiol 1992;13:257-263.
19. Rietb KG, Fujiwana K, Di Chiro G, et al. Serial measunements of CT attenuation and specific gravity in experimental cerebral edema Radiology 1980; 135: 343-348.
20. Tomsick TA. Sensitivity and prognostic value of early CT in occlusion of the middle cerebral artery trunk (Commentary) AJNR Am J Neuroradiol 1994; 15: 16-18.
21. Shriger DL, Kalafut M, Storkman S, et al. Cranial Computed tomography interpretation in acute stroke, physician accuracy in determining eligibility for thrombolytic therapy JAMA 1993; 279: 1293- 1297.
22. Brott T, Marler JR, Olinger CP, et al. Measurements of acute cerebral infarction: lesion size by computed tomography. Stroke 1989; 20: 871-875.
23. Tomsick T, Brott T, Barsan W, et all. Prognostic value of the hyperdense middle cerebral artery sign and stroke scale score before ultra early thrombolytic therapy. AJNR Am J Neuroradiol. 1996; 17: 79-85.
24. Van Swieten JC, Koudstaal PJ, Visser MC. Schauten HJA, van Gijn J. Interobserver agreement for the assessment of handicap in Stroke patients. Stroke 1998: 19: 604-607.