背景:间质性肺异常(ILA)与疾病的进一步进展有关,死亡风险增加,老年人的肺功能下降,这值得足够的关注。
目的:本研究的目的是使用低剂量CT(LDCT)量化中国非吸烟无症状城市队列中间质性肺异常(ILA)的程度,并分析与年龄相关的病理变化。
方法:我们回顾性分析了733名受试者的临床数据和胸部LDCT图像,这些受试者根据年龄分为3组:18-39岁、40-59岁和≥60岁。此外,我们选择了40例肺大泡切除术后存档的蜡包埋肺组织块,并对相同年龄组进行了分类。ILA的四个代表性CT征象,包括小叶间隔增厚(ILST),小叶内间质增厚(ILIT),毛玻璃不透明度(GGO),和网状阴影(RS),根据受影响面积的百分比进行半量化。比较不同性别和年龄组ILA4种CT征象的评分和分布。分析与年龄相关的病理改变。
结果:ILA发现主要在下叶和胸膜下区域。所有40岁以下受试者的四种CT征象的半定量评分均为0.然而,在40岁以上的受试者中,分数随着年龄的增长而逐渐增加,尽管他们中的大多数仍然很低。肺泡的大小增加,肺泡数量减少,肺泡隔膜变薄,ATII细胞的数量随着年龄的增长而增加。不同年龄组间差异有统计学意义(χ2=50.624,P=0.033;χ2=80.000,P=0.043;χ2=33.833,P=0.000;χ2=13.525,P=0.031)。肺泡隔巨噬细胞数量和胶原纤维百分比增加,而弹性纤维的百分比随着年龄的增长而下降。不同年龄组间差异无统计学意义(χ2=19.817,P=0.506;χ2=52.419,P=0。682;χ2=54.868,P=0.518)。
结论:当上述四个CT征象位于中央上部区域时,分数有中等或高分,确定潜在的病理原因至关重要。ILA可能是慢性肺损伤的结果。
BACKGROUND: Interstitial lung abnormalities (ILA) are associated with further disease progression, increased mortality risk, and decline in lung function in the elderly, which deserves enough attention.
OBJECTIVE: The objective of this study was to quantify the extent of interstitial lung abnormalities (ILA) in a non-smoking asymptomatic urban cohort in China using low-dose CT (LDCT) and to analyze the age-related pathological changes.
METHODS: We retrospectively analyzed clinical data and chest LDCT images from a cohort of 733 subjects who were categorized into 3 groups: 18-39, 40-59, and ≥60 years old according to age. Furthermore, we selected 40 cases of wax-embedded lung tissue blocks archived after pulmonary bullectomy and the same age groups were categorized. Four representative CT signs of ILA, including interlobular septal thickening (ILST), intralobular interstitial thickening (ILIT), ground-glass opacity (GGO), and reticular shadow (RS), were semi-quantified based on the percentage of the affected area. The scores and distribution of four CT signs of ILA were compared between different sex and age groups. The age-related pathological changes were analyzed.
RESULTS: The ILA findings were found predominantly in the lower lobes and the subpleural region. The semi-quantitative scores of four CT signs in all subjects under 40 were 0. However, in subjects over 40 years old, the scores gradually increased with age, although most of them remained low. The size of the alveoli increased, the number of alveoli decreased, the alveolar septum became thinner, and the number of ATII cells increased with age. A statistically significant difference was observed among the different age groups (χ2=50.624, P=0.033; χ2=80.000, P=0.043; χ2=33.833, P=0.000; χ2=13.525, P=0.031). The macrophage population and the percentage of collagen fibers in the alveolar septum increased, while the percentage of elastic fibers decreased with age. There was no significant difference among the different age groups (χ2=19.817, P=0.506; χ2=52.419, P=0. 682; χ2=54.868, P=0.518).
CONCLUSIONS: When the four CT signs mentioned above are in the upper central area, and the score has a medium or high score, it is crucial to determine the underlying pathological causes. ILA may be the result of chronic lung injury.