Hudgins P A
Department of Radiology, Emory University School of Medicine, Atlanta, Georgia.
Neuroimaging Clin N Am. 1994 Feb;4(1):101-15.
Iodinated intravenous contrast material for CT of the extracranial head and neck is extremely useful in almost all clinical settings. Contrast material facilitates visualization of the carotid artery and jugular vein; helps delineate the full extent of neoplastic and inflammatory lesions, and in limited circumstances can suggest a precise diagnosis based on a particular pattern of enhancement. The role of gadolinium is not as clear. Gadolinium chelates are not routinely needed to opacify vessels, and with operator-dependent changes in pulse sequence parameters, contrast between a lesion and normal structures can be maximized. A number of studies, however, have shown that gadolinium can improve detection of perineural or intracranial spread of disease; confirm necrosis within lymph nodes, abscesses, or tumors; and more accurately show the full extent of disease into surrounding soft tissues. It is impossible to predict before imaging which patients will benefit from the addition of MR contrast agents, and for that reason enhanced images are often routinely acquired.
用于颅外头颈部CT检查的碘化静脉造影剂在几乎所有临床情况下都极为有用。造影剂有助于显示颈动脉和颈静脉；有助于勾勒肿瘤性和炎性病变的全貌，在有限的情况下，可根据特定的强化模式做出精确诊断。钆的作用尚不清楚。钆螯合物通常不需要用于使血管显影，并且随着脉冲序列参数的操作者依赖性变化，病变与正常结构之间的对比度可最大化。然而，一些研究表明，钆可以改善对疾病神经周围或颅内扩散的检测；确认淋巴结、脓肿或肿瘤内的坏死；并更准确地显示疾病向周围软组织的全貌。在成像前无法预测哪些患者会从添加磁共振造影剂中获益，因此通常会常规采集增强图像。
