Table 1

Characteristics of included studies

StudyStudy designPatient number (% men)Mean age (years)Initial stroke severity (NIHSS)T2*-GRE MRI parametersCMBs prevalence (95% CI)Differences
CMBs(+) versus CMBs (−) groups
Thrombolysis (see online supplementary table S3)FU time (days)Symptomatic ICH definitionOther risk factors for thrombolysis-related ICH accounted for
Field strength (Tesla) Echo time (ms)Section thickness (mm)
Fiehler 2007Prospective, multicentre (13)570 (–)69 (59–77)*13 (IQR:8–17)14–495–715.1% (9.1 to 19.7%)No differences in: sex and NIHSS score. Median age (IQR): 72 (65–79) versus 69 (58–77); (p=0.001)IV tPA within 6 h10ICH with worsening of ≥4 points on NIHSS
Kim 2006Retrospective, single centre65 (57)6730515.7% (8.1 to 26.4%)Hypertension and age associated with CMBs (p<0.05)IV tPA within 3 h (n=12); IA UK within 6 h (n=53)1–3Symptomatic haemorrhage: any neurological deterioration within the first 48 h that could be attributed to the presence haemorrhage on follow-up MRIAge, hypertension, diabetes, atrial fibrillation, stroke history, smocking, NIHSS score
Kakuda 2005Prospective, multicentre (3)70 (44.3)70.511±9.2/13±9.8 CMB (+)/(−) (mean/SD)1.514–47538.5% (26.7 to 51.4%)No differences in age, time to treatment, blood pressure, NIHSS, hypertension. Diabetes, dyslipidaemia, smokingIV tPA within 6 h30ICH with worsening of ≥2 points on NIHSS
Derex 2004Retrospective, single centre44 (–)63.2+/−14.114±5.8 (mean/SD)1.526518.2% (8.2 to 32.7%)IV tPA at two different doses within 7 h7ICH with worsening of ≥4 points on NIHSS or ≥1 point on NIHSS consciousness levelDelay to treatment; tPA dose
Kidwell 2002Retrospective, single centre41 (–)1.515712.2% (4.1 to 26.2%)No differences in age, hypertension, diabetes, hypercholesterolaemia, smoking, and severity of pretreatment neurological deficit.IV/IA tPA within 3 h; IA UK or tPA mechanical clot disruption during IA thrombolysis7ICH with worsening of ≥4 points on NIHSS or ≥1 point on NIHSS consciousness levelThrombolysis regimen
  • CMB, cerebral microbleeds; FU, follow-up; GRE, gradient-recalled echo; IA: intra-arterial; ICH, intracerebral haemorrhage; IQR, interquartile range; IV, intravenous; NIHSS, National Institute of Health Stroke Scale; SD, standard deviation; tPA, tissue plasminogen activator.

  • *Median age (interquartile range)