Department of Radiology, Division of Neuroradiology, University of Pennsylvania, Philadelphia, PA, USA; Department of Neurology, Medical University of Silesia, Katowice, Poland.
Department of Diagnostic Radiology & Nuclear Medicine, University of Maryland Medical Center, Baltimore, MD, USA; King Khalid University, Abha, The Kingdom of Saudi Arabia.
Adv Med Sci. 2014 Mar;59(1):108-13. doi: 10.1016/j.advms.2013.09.001. Epub 2014 Mar 27.
Children with sickle cell anemia (SCA), who have mean blood flow velocities <170 cm/s in the terminal internal carotid (tICA) or middle cerebral (MCA) arteries on transcranial Doppler ultrasonography (TCD), are considered to be at low risk of stroke. The prevalence of intracranial stenosis, which raises the risk of stroke, is not known in these children. Here, we estimated the prevalence of stenosis and explored its association with silent cerebral infarcts determined based on Magnetic Resonance (MR) scans.
PATIENTS/METHODS: We studied prospectively a cohort of 67 children with SCA without prior clinically overt stroke or TIA (median age 8.8 years; range limits 2.3-13.1 years; 33 females) and with TCD mean velocity <170 cm/s. They underwent MR imaging of the brain and MR angiography of intracranial arteries.
In 7 children (10.5%, 95% CI: 4.9-20.3%) we found 10 stenoses, including 4 with isolated left tICA stenosis and 3 with multiple stenoses. We found silent infarcts in 26 children (37.7%, 95% CI: 27.2-49.5%). The median number of infarcts in an affected child was 2 (range limits: 1-9), median volume of infarcts was 171 mm(3) (range limits: 7-1060 mm(3)), and median infarct volume in relation to total brain volume was 0.020% (range limits: 0.001-0.101%). The number and volume of infarcts were significantly higher in children with arterial stenosis (both p=0.023).
The prevalence of intracranial arterial stenosis in children with SCA classified as at low risk of stroke by TCD mean velocity <170 cm/s is high. Children with stenosis are at higher risk of brain parenchymal injury as they have more silent cerebral infarcts.
患有镰状细胞贫血（SCA）的儿童，经颅多普勒超声（TCD）检查发现终末颈内动脉（tICA）或大脑中动脉（MCA）的血流速度<170cm/s，被认为中风风险较低。但目前尚不清楚这些儿童中颅内狭窄的患病率，而颅内狭窄会增加中风风险。在此，我们评估了狭窄的患病率，并探讨了其与基于磁共振（MR）扫描确定的无症状性脑梗死之间的关联。
患者/方法：我们前瞻性研究了一组无先前临床显性中风或 TIA 的 67 名 SCA 儿童（中位年龄 8.8 岁；范围限制 2.3-13.1 岁；33 名女性），且 TCD 平均速度<170cm/s。他们接受了脑部磁共振成像和颅内动脉磁共振血管造影检查。
在 7 名儿童（10.5%，95%CI：4.9-20.3%）中发现 10 处狭窄，包括 4 例单纯左侧 tICA 狭窄和 3 例多处狭窄。我们在 26 名儿童（37.7%，95%CI：27.2-49.5%）中发现了无症状性梗死。受影响儿童的中位数梗死数量为 2 个（范围限制：1-9 个），中位数梗死体积为 171mm³（范围限制：7-1060mm³），中位数梗死体积与全脑体积的比值为 0.020%（范围限制：0.001-0.101%）。在 TCD 平均血流速度<170cm/s 被归类为中风低危的儿童中，动脉狭窄者的梗死数量和体积均显著更高（两者均 p=0.023）。
在 TCD 平均血流速度<170cm/s 被归类为中风低危的 SCA 儿童中，颅内动脉狭窄的患病率较高。有狭窄的儿童发生脑实质损伤的风险更高，因为他们有更多的无症状性脑梗死。
