The goals of imaging in a patient with acute strokes are to exclude hemorrhage, differentiate between irreversibly affected brain tissue and reversibly impaired tissue and identify stenosis or occlusion of major extra and intracranial arteries. In this way we can select patients who are candidates for thrombolytic therapy. Assessment of early infarction signs is now included in some guidelines and approval documents for thrombolysis. Thrombolysis is not widely implemented for treatment of acute ischemic stroke and uncertainty about the interpretation of early infarction signs on...

Brain CT findings of 192 patients examined for clinical symptoms of acute brain stroke were retrospectively studied. All patients underwent an initial brain CT on the time of presenting to our Hospital and second CT 48 hours later. Presence or absence of the following early signs was documented: hypoattenuating brain tissue, obscuration of lentiform nucleus, dense middle cerebral artery (MCA), “insular ribbon” sign, loss of sulcal effacement. Importantly, hypoattenuation on CT is highly specific for irreversible ischemic brain damage, if detected within first 6 hours....

CT scans were analyzed for the following: • Hypoattenuating brain tissue in 82 patients (Fig.1) • Obscuration of lentiform nucleus in 16 patients (Fig.2) • Dense middle cerebral artery in 27 patients(Fig.3) • ‘Insular ribbon’ sign in 35 patients (Fig.4) • Loss of sulcal effacement in 32 patients (Fig.5)

CT has the advantage of being available 24 hours a day and is the gold standard for hemorrhage. On CT 60% of infarcts are seen within 3-6 hrs and virtually all are seen in 24 hours. The overall sensitivity of CT in diagnosing stroke is 64% and the specificity is 85%. The sensitivity and specificity of early infarction signs on CT scans are generally not good. It would appear, however, that the sensitivity of early infarction signs on CT scans is poorer than the specificity....

1. Joanna M. Wardlaw and Orell Mielke. Early Signs of Brain Infarction at CT: Observer Reliability and Outcome after Thrombolytic Treatment—Systematic Review. Radiology May 2005 235:444-453. 2. Diederik M. Somford, Paul J. Nederkoorn, Dirk R. Rutgers, L. Jaap Kappelle, Willem P. T. M. Mali, Jeroen van der Grond. Proximal and Distal Hyperattenuating Middle Cerebral Artery Signs at CT: Different Prognostic Implications. Radiology June 2002 223:667-671. 3. Enrique Marco de Lucas,Elena Sánchez, Agustín Gutiérrez, Andrés González Mandly, Eva Ruiz, Alejandro Fernández Flórez, et al. CT Protocol...

I. Georgiou, MD Radiology Department, “St. Savvas” Oncologic Hospital, Athens, Greece E. Tsokou, MD Radiology Department, “Alexandra” General Hospital, Athens, Greece