New Cerebral Microbleeds After Mechanical Thrombectomy for Large-Vessel Occlusion Strokes

Number of cerebral microbleeds after intracranial/extracranial stenting and dual antiplatelet therapy

BACKGROUND

Cerebral microbleeds (CMBs) are small (<1 cm) perivascular hemosiderin depositions. They may be visible in T2* or susceptibility-weighted magnetic resonance imaging (MRI) sequences. CMBs may indicate an increased risk of intracerebral hemorrhage (ICH) or vascular disease. Cerebral white matter changes indicate small vessel disease (SVD), which is also related to CMBs. In cerebral vascular treatment, dual antiplatelet therapy (DAPT) is routinely used after stenting. We surveyed our cerebral stenting case series for changes in the number of CMBs.

METHODS

Patients receiving extracranial or intracranial stenting between 2018 and 2020 were included. All patients received DAPT after stenting. Changes in CMBs, SVD degree, and other findings from pretreatment to follow-up MRI were recorded. Differences between stented artery supplying territory and other territories were compared.

RESULTS

The average age of the 75 enrolled patients was 65.37 years ± 11.53 (50 male and 25 female patients); 84 extracranial or intracranial stentings were performed. The average Fazekas scale score was 1.32 ± 0.77. Significantly more CMBs developed in the initial ≥6 CMB group than in the initial 0 and 1-5 CMB groups (7 ± 3.6 vs 0.56 ± 1.06, 1.45 ± 3.32, p < 0.001). No significant difference in increased CMBs was observed between the initial 0 and 1-5 CMB groups. Significantly more CMBs developed in the stented artery supplying territory than elsewhere (0.6 ± 0.13 vs 0.44 ± 0.17, p < 0.05). No ICH was noted in our case series.

CONCLUSION

Preexisting CMB was a risk factor for the onset of new CMBs after stenting and DAPT. Poststenting and DAPT statistically increased CMBs in stented artery supplying territories at short-term follow-up.

Factors associated with the new appearance of cerebral microbleeds after endovascular treatment for unruptured intracranial aneurysms

PURPOSE

Endovascular treatment of unruptured intracranial aneurysms may increase cerebral microbleeds (CMBs) in postprocedural T2*-weighted MRIs, which may be a risk for future intracerebral hemorrhage. This study examined the characteristics of postprocedural CMBs and the factors that cause their increase.

METHODS

The patients who underwent endovascular treatment for unruptured intracranial aneurysms from April 2016 to February 2018 were retrospectively analyzed. Treatment techniques for endovascular treatment included simple coiling, balloon-assisted coiling, stent-assisted coiling, or flow diverter placement. To evaluate the increase in CMBs, a head MRI including diffusion-weighted imaging and T2*-weighted MRIs was performed on the preprocedural day; the first postprocedural day; and at 1, 3, and 6 months after the procedure.

RESULTS

Among the 101 aneurysms that were analyzed, 38 (37.6%) showed the appearance of new CMBs. In the multivariate analysis examining the causes of the CMB increases, chronic kidney disease, a higher number of preprocedural CMBs, and a higher number of diffusion-weighted imaging-positive lesions on the first postprocedural day were independent risk factors. Furthermore, a greater portion of the increased CMBs was found in cortical and subcortical lesions of the treated vascular perfusion area within 1 month after the procedure.

CONCLUSION

In endovascular treatment for unruptured intracranial aneurysms, CMBs tended to increase in patients with small vessel disease before the procedure, and it was also implicated in hemorrhagic changes after periprocedural microinfarction.

A Follow-up Study of Cerebral Microbleeds in Patients Who Received Stents for Symptomatic Cerebral Artery Stenosis

BACKGROUND

The aims of this study were to explore (i) the dynamic changes in cerebral microbleeds (CMBs) in patients with symptomatic cerebral artery stenosis who received endovascular stent-assisted angioplasty and (ii) the risk factors associated with the new incidence of CMBs as well as whether CMBs increased the risk of vascular events in these patients.

METHODS

Clinical information and magnetic resonance images were collected on admission and 3 months after endovascular stent-assisted angioplasty. Based on susceptibility-weighted imaging, the patients were divided into groups with or without newly developed CMBs, and between-group differences in risk factors were compared. We also compared whether CMBs increased the risk of vascular events among those patients.

RESULTS

Seventy-three patients completed the relevant follow-up examinations. After an average follow-up period of 109 days, 7 (9.6%) patients showed new CMBs. A univariate analysis showed that the number of lacunar infarcts and the increase in systolic blood pressure were higher in patients with new CMBs than in those without new CMBs, and these differences were significant (P = 0.034, P = 0.001). Increased systolic blood pressure was an independent risk factor for developing new CMBs (P = 0.017).

CONCLUSIONS

CMBs may be a continuously progressing cerebral small-vessel disease. The newly developed CMBs in patients with intracranial and/or extracranial stents were associated with increased systolic blood pressure but not with the number of baseline CMBs.

Cerebral White Matter Hyperintensities and Microbleeds in Acute Ischemic Stroke: Impact on Recanalization Therapies. A Review of the Literature

Cerebral white matter hyperintensities (WMH) and cerebral microbleeds (CMBs) are frequently seen on brain imaging acquired for acute ischemic stroke. Given the raising use of recanalization therapies - both intravenous and endovascular - the interest on the impact of WMH and CMBs on the risk of intracerebral hemorrhage and on functional outcome is growing. In this review, we will discuss the relevance of WMH and CMBs among patients with an acute ischemic stroke, focusing on the implications for recanalization therapies.