Baron R L, Lee J K, Sagel S S, Peterson R R
Radiology. 1982 Jan;142(1):121-5. doi: 10.1148/radiology.142.1.7053521.
Recognition of variations in size, shape, and density of the normal thymus on computed tomographic (CT) scans is of paramount importance, lest it be misinterpreted as an abnormal mediastinal mass. Studying patients subsequently proved free of active chest disease, we analyzed 154 CT scans of the mediastinum, performed on a fourth-generation scanner, to determine the incidence of visualization and appearance of the normal thymus. The thymus was seen in 100% of patients under age 30, 73% of patients between 30 and 49 years, and in 17% of patients over 49 years of age. The thickness of the thymus showed a definite decrease in size with increasing age; although the width showed a similar general tendency, a wide variation was noted within each age group. In younger patients, the density of the thymus was similar to that of muscle; the attenuation values progressively decreased in older patients, finally approaching that of fat.
在计算机断层扫描（CT）上识别正常胸腺的大小、形状和密度变化至关重要，以免将其误诊为异常纵隔肿块。我们对随后被证明无活动性胸部疾病的患者进行研究，分析了在第四代扫描仪上进行的154例纵隔CT扫描，以确定正常胸腺的显影率和外观。在30岁以下的患者中，胸腺显影率为100%；在30至49岁的患者中，胸腺显影率为73%；在49岁以上的患者中，胸腺显影率为17%。胸腺厚度随年龄增长呈明显减小趋势；尽管宽度也呈现类似的总体趋势，但各年龄组内宽度变化较大。在年轻患者中，胸腺密度与肌肉相似；在老年患者中，衰减值逐渐降低，最终接近脂肪的衰减值。
