Mannel Robert K, Sandhu Sukwinder J, Silliman Scott L
Department of Neurology, College of Medicine-Jacksonville, University of Florida, Jacksonville, FL, USA.
Division of Neuroradiology, Department of Radiology, College of Medicine-Jacksonville, University of Florida, Jacksonville, FL, USA.
SAGE Open Med Case Rep. 2017 Dec 19;5:2050313X17748864. doi: 10.1177/2050313X17748864. eCollection 2017.
While non-contrast head computed tomography is effective in detecting blood, it is not sensitive in diagnosing hyperacute ischemic stroke. One neuroradiologic marker for early thromboembolic occlusion of the distal middle cerebral artery is the middle cerebral artery "dot" sign. The "dot" seen on the typical axial plane represents a hyperdensity of the middle cerebral artery in the Sylvian fissure. A review of medical literature was conducted via PubMed utilizing search phrases "MCA," "dot," and "sign." The review was limited to the intravenous tissue-type plasminogen activator era, 1996 and on. Articles were analyzed to determine the use of the sagittal plane of non-contrast head computed tomography to locate the middle cerebral artery "dot" sign. The search terms yielded 11 results which revealed that computed tomography reconstruction and sagittal planes were not used for detection of the middle cerebral artery "dot" signs. Our patient had no known past medical history. The initial non-contrast head computed tomography was read as having a hypodensity in the right insular region and a middle cerebral artery "dot" sign. Multiplanar reconstruction of the computed tomography demonstrated a hyperdense sagittal string-like appearance of the middle cerebral artery along the Sylvian fissure. Computed tomography angiography confirmed the M2 occlusion. This is the first report of using the head computed tomography sagittal plane for diagnosis of the middle cerebral artery "dot" sign. Incorporating multiplanar reconstruction and producing the sagittal plane may lead to a higher sensitivity of the middle cerebral artery "dot" sign. Further studies incorporating a patient cohort will be needed to determine how much the sagittal plane view augments predictive value of the middle cerebral artery "dot" sign.
虽然非增强头部计算机断层扫描在检测出血方面有效，但在诊断超急性缺血性卒中时并不敏感。大脑中动脉远端早期血栓栓塞性闭塞的一个神经放射学标志物是大脑中动脉“点”征。在典型轴位平面上看到的“点”代表外侧裂内大脑中动脉的高密度影。通过PubMed使用搜索词“MCA”、“点”和“征”对医学文献进行了综述。该综述仅限于1996年及以后的静脉注射组织型纤溶酶原激活剂时代。对文章进行分析以确定非增强头部计算机断层扫描矢状面用于定位大脑中动脉“点”征的情况。搜索词产生了11条结果，显示计算机断层扫描重建和矢状面未用于检测大脑中动脉“点”征。我们的患者无已知既往病史。最初的非增强头部计算机断层扫描显示右侧岛叶区域低密度影及大脑中动脉“点”征。计算机断层扫描的多平面重建显示大脑中动脉沿外侧裂呈高密度矢状条索样外观。计算机断层扫描血管造影证实了M2段闭塞。这是首次使用头部计算机断层扫描矢状面诊断大脑中动脉“点”征的报告。纳入多平面重建并生成矢状面可能会提高大脑中动脉“点”征的敏感性。需要进一步纳入患者队列的研究来确定矢状面视图能在多大程度上增强大脑中动脉“点”征的预测价值。
