Postert T, Federlein J, Weber S, Przuntek H, Büttner T
Department of Neurology, Ruhr University Bochum, Berlin, Germany.
Stroke. 1999 Aug;30(8):1702-6. doi: 10.1161/01.str.30.8.1702.
Second harmonic imaging (SHI) is a new ultrasound technique that is able to detect microbubbles in the tissue vascular space. The aim of this pilot study was to prove that this technique may detect focal abnormalities of cerebral echo-contrast enhancement in acute hemispheric stroke.
Two male patients (aged 72 and 64 years) were included who presented with acute onset of severe hemiparesis and no established demarcation of the ischemic area in CT scans. After bolus application of galactose-based microbubbles, axial SHI examinations in a diencephalic plane of sections were performed using the transtemporal approach. Ultrasound investigations were recorded and evaluated offline. In both individuals demarcated focal abnormalities of cerebral contrast enhancement were detectable: in patient 1 the region of the lentiform nucleus and the adjacent parts of the temporoparietal lobe was affected, and in patient 2 a large region including the lentiform nucleus and cortical white matter was involved for at least 24 hours. Follow-up CT scans demonstrated a striatocapsular infarct in patient 1 and complete MCA infarction in patient 2, correlating with the presumed ischemic area in acute ultrasound examinations. The patient with complete MCA infarction showed missing contrast enhancement in the entire hemisphere of the affected side in follow-up SHI examinations. He died of malignant space-occupying brain edema. In the patient with the striatocapsular infarction, reappearance of echo-contrast enhancement in the ischemic area was assessable after 1 week.
SHI may identify focal abnormalities of cerebral echo-contrast enhancement in acute hemispheric stroke. Furthermore, this technique helps to determine size, localization, and prognosis of the ischemic region and could be useful for bedside assessment of echo-contrast agent distribution related to brain tissue perfusion.
二次谐波成像（SHI）是一种新型超声技术，能够检测组织血管间隙中的微泡。本初步研究的目的是证明该技术可检测急性半球性卒中时脑回声对比增强的局灶性异常。
纳入两名男性患者（年龄分别为72岁和64岁），他们均急性起病，出现严重偏瘫，且CT扫描未明确显示缺血区域的界限。在静脉推注基于半乳糖的微泡后，采用经颞部途径在中脑平面进行轴向SHI检查。超声检查记录后离线评估。在两名患者中均检测到脑对比增强的局灶性异常：患者1的豆状核区域及颞顶叶相邻部分受累，患者2的一个包括豆状核和皮质白质的大区域至少24小时受累。随访CT扫描显示患者1为纹状体内囊梗死，患者2为大脑中动脉完全梗死，与急性超声检查推测的缺血区域相关。大脑中动脉完全梗死的患者在随访SHI检查中患侧整个半球对比增强缺失。他死于恶性占位性脑水肿。在纹状体内囊梗死的患者中，1周后可评估缺血区域回声对比增强再次出现。
SHI可识别急性半球性卒中时脑回声对比增强的局灶性异常。此外，该技术有助于确定缺血区域的大小、位置和预后，并且可能有助于床边评估与脑组织灌注相关的对比剂分布情况。
