Serial CT and MRI of ischaemic cerebral infarcts: frequency and clinical impact of haemorrhagic transformation

The frequency, predisposing factors and clinical consequences of haemorrhag ic infarcts and damaged blood-brain barrier as shown by contrast enhancemen t (CE) in ischaemic cerebral infarcts are controversial. We prospectively c ompared the sensitivity of CT and MRI to haemorrhagic transformation (HT) a nd CE. We also wished to investigate the clinical significance of HT and fa ctors possibly associated with it. We studied 36 patients with acute ischae mic infarcts in the middle cerebral artery territory during the first 2 wee ks after the ictus. After CT and rating of the neurological deficit on admi ssion, serial examinations with clinical neuromonitoring, contrast-enhanced CT and MRI were done on the same day. The occurrence and severity of HT we re correlated with CE, stroke mechanism, infarct size, development of neuro logical deficits and antithrombotic treatment. The frequency of HT detected by MRI was 80%. CE usually preceded HT or was seen simultaneously. MRI had a higher sensitivity than CT to HT and CE. Severity of HT was positively c orrelated with infarct size (P < 0.01). HT had no influence on patient's ne urological status. Neither the type of antithrombotic treatment nor the str oke mechanism was associated with the severity of HT. No parenchymal haemor rhage occurred.