Background: Recent studies suggest that superficially located cerebellar ICH and microbleeds might point towards sporadic cerebral amyloid angiopathy (CAA).

Aims: We investigated the proportion of cerebellar ICH and asymptomatic macro- and microbleeds in Dutch-type hereditary CAA (D-CAA), a severe and essentially pure form of CAA.

Methods: Symptomatic patients with D-CAA (defined as ≥1 symptomatic ICH) and presymptomatic D-CAA mutation-carriers were included. We assessed MRI scans for symptomatic (cerebellar) ICH and asymptomatic cerebellar macro- and microbleeds according to the STRIVE-criteria. Location was assessed as superficial-cerebellar (cortex, vermis or juxta-cortical) or deep-cerebellar (white matter, pedunculi cerebelli and grey nuclei).

Results: We included 63 participants (mean age 58 years, 60% women, 42 symptomatic). In total, the 42 symptomatic patients with D-CAA had 107 symptomatic ICH (range 1-7). None of these ICH were located in the cerebellum. Six of 42 (14%, 95%CI 4-25%) symptomatic patients and none of the 21 (0%, 95%CI 0-0%) presymptomatic carriers had ≥ 1 asymptomatic cerebellar macrobleed(s). All macrobleeds were superficially located. Cerebellar microbleeds were found in 40 of 63 (64%, 95%CI 52-76) participants (median 1.0, range 0-159), 81% in symptomatic patients and 29% in presymptomatic carriers. All microbleeds were strictly or predominantly superficially (ratio superficial versus deep 15:1) located.

Conclusions: Superficially located asymptomatic cerebellar macrobleeds and microbleeds are common in D-CAA. Cerebellar microbleeds are already present in the presymptomatic stage. Despite the high frequency of cerebellar micro and macrobleeds, CAA pathology did not result in symptomatic cerebellar ICH in patients with D-CAA.

背景：最近的研究表明，位于浅表的小脑 ICH 和微出血可能表明散发性脑淀粉样血管病 (CAA)。

目的：我们调查了荷兰型遗传性 CAA（D-CAA）（一种严重且本质上纯粹的 CAA 形式）中小脑 ICH 以及无症状大出血和微出血的比例。

方法：纳入有症状的 D-CAA 患者（定义为≥1 次有症状的 ICH）和症状前的 D-CAA 突变携带者。我们根据 STRIVE 标准评估 MRI 扫描是否有症状（小脑）ICH 和无症状小脑大出血和微出血。位置被评估为小脑浅层（皮质、蚓部或近皮质）或小脑深部（白质、小脑脚和灰核）。

结果：我们纳入了 63 名参与者（平均年龄 58 岁，60% 为女性，42 名有症状）。总共，42 名有症状的 D-CAA 患者有 107 名有症状的 ICH（范围 1-7）。这些 ICH 均不位于小脑。 42 名（14%，95%CI 4-25%）有症状患者中，有 6 名（14%，95%CI 4-25%）有症状，而 21 名（0%，95%CI 0-0%）症状前携带者中没有一人有≥1 次无症状小脑大出血。所有大出血均在表面定位。 63 名参与者中，有 40 名（64%，95%CI 52-76）（中位数 1.0，范围 0-159）发现小脑微出血，其中 81% 为有症状患者，29% 为症状前携带者。所有微出血均严格或主要位于浅表（浅表与深部的比例为 15:1）。

结论：浅表无症状小脑大出血和微出血在 D-CAA 中很常见。小脑微出血在症状前阶段就已经存在。尽管小脑微出血和大出血的发生率很高，但 CAA 病理学并未导致 D-CAA 患者出现症状性小脑 ICH。