Acute ischaemic brain lesions in intracerebral haemorrhage: multicentre cross-sectional magnetic resonance imaging study

Abstract

Subclinical acute ischaemic lesions on brain magnetic resonance imaging have recently been described in spontaneous intracerebral haemorrhage, and may be important to understand pathophysiology and guide treatment. The underlying mechanisms are uncertain. We tested the hypothesis that ischaemic lesions are related to magnetic resonance imaging markers of the severity and type of small-vessel disease (hypertensive arteriopathy or cerebral amyloid angiopathy) in a multicentre, cross-sectional study. We studied consecutive patients with intracerebral haemorrhage from four specialist stroke centres, and age-matched stroke service referrals without intracerebral haemorrhage. Acute ischaemic lesions were assessed on magnetic resonance imaging (<3 months after intracerebral haemorrhage) using diffusion-weighted imaging. White matter changes and cerebral microbleeds were rated with validated scales. We investigated associations between diffusion-weighted imaging lesions, clinical and radiological characteristics. We included 114 patients with intracerebral haemorrhage (39 with clinically probable cerebral amyloid angiopathy) and 47 age-matched controls. The prevalence of diffusion-weighted imaging lesions was 9/39 (23%) in probable cerebral amyloid angiopathy-related intracerebral haemorrhage versus 6/75 (8%) in the remaining patients with intracerebral haemorrhage (P = 0.024); no diffusion-weighted imaging lesions were found in controls. Diffusion-weighted imaging lesions were mainly cortical and were associated with mean white matter change score (odds ratio 1.14 per unit increase, 95% confidence interval 1.02-1.28, P = 0.024) and the presence of strictly lobar cerebral microbleeds (odds ratio 3.85, 95% confidence interval 1.15-12.93, P = 0.029). Acute, subclinical ischaemic brain lesions are frequent but previously underestimated after intracerebral haemorrhage, and are three times more common in cerebral amyloid angiopathy-related intracerebral haemorrhage than in other intracerebral haemorrhage types. Ischaemic brain lesions are associated with white matter changes and cerebral microbleeds, suggesting that they result from an occlusive small-vessel arteriopathy. Diffusion-weighted imaging lesions contribute to the overall burden of vascular-related brain damage in intracerebral haemorrhage, and may be a useful surrogate marker of ongoing ischaemic injury from small-vessel damage.

Ischemic lesions, blood pressure dysregulation, and poor outcomes in intracerebral hemorrhage

“…[5][6][7][8][9][10] Over the last several years, a growing number of studies have characterized the presence and frequency of ischemic lesions remote from the acute hematoma visualized on diffusion-weighted imaging (DWI) in patients with primary ICH undergoing MRI. [11][12][13][14][15][16][17][18][19] Across these series, remote DWI lesions are visualized in 11%-41% of patients. There have been conflicting reports of an association between DWI lesions and large fluctuations in BP in the acute hospital setting.…”

“…However, the median hematoma volume in our study (9.1 mL) is comparable to the majority of prior MRI-based reports. [12][13][14][15] Of note, the median hematoma volume in the INTERACT II study was 11 mL. 7 MRIs were not all acquired at routine timepoints or with identical magnet strengths and sequence parameters.…”

Ischemic brain injury in cerebral amyloid angiopathy

“…54 However, the cytotoxic edema that occurs in the acute phase of the infarct (first 1 to 2 weeks), can be visible on MRI as hyperintense foci of restricted diffusion on diffusion-weighted imaging (DWI). Focal DWI lesions have shown to be more common in patients with CAA-related ICH (15% to 23%) than in patients with Alzheimer's disease and controls 59,60 and continue to occur in high frequency beyond the post-ICH period. 61 Importantly, DWI lesions have been found to be associated with other imaging markers of CAA (i.e., WMH volume and lobar microbleeds), but not with traditional vascular risk factors such as hypertension.…”

Prevalence and mechanisms of cortical superficial siderosis in cerebral amyloid angiopathy

“…17 and white matter hyperintensities (leukoaraiosis) 18 were recorded according to predefined standardized criteria. CMBs were evaluated on T2*-GRE images.…”