Multifocal low-signal brain lesions on T2*-weighted gradient-echo imaging

Multifocal small low-signal lesions on T2*-weighted gradient-echo (GE) MRI are reported to be common in the brain of hypertensive patients. We examine d factors associated with these lesions. For one year, we routinely obtaine d T2*-weighted GE images (TR 1000 TE 30 ms, flip angle = 20 degrees) in all adult patients (314) who underwent brain MRI in our hospital, using a 1.5 T superconducting magnet. Patients with multifocal small low-signal lesions with a known or presumed pathogenesis or any condition which may cause int racerebral haemorrhage, such as brain tumours, were excluded from further a nalysis. Thus, 191 cases remained (104 men and 87 women; age, 62.8 +/- 11.0 years, range, 30-89 years). The overall prevalence of multifocal small low -signal lesions on the GE images was 15.2 % (29/191); they were commonly in the cerebral white matter and basal ganglia. They were detected in 12 (52. 2 %) of the 23 patients with prior symptomatic brain hemorrhage, 12 (20.7 % ) of the 58 with prior symptomatic infarcts, and only five (4.5 %) of 110 w ithout a prior stroke. Logistic regression analysis indicated that multifoc al small low-signal lesions were significantly correlated with a symptomati c acute brain haemorrhage (odds ratio, 13.17), chronic hypertension (4.00) and a symptomatic acute infarct (3.71). The association with symptomatic ac ute brain haemorrhage suggests that this finding may represent subclinical microhaemorrhage. The diagnostic potential of this finding to identify indi viduals at risk of symptomatic intracerebral haemorrhage may require furthe r investigation.