Fibrous foci are not pulmonary nodules. The two types of lesions are different and have different causes.
Fibrotic foci are old lesions that are scarred after inflammation of lung parenchyma cells, i.e., fibrous striated lesions in the lungs, while pulmonary nodules are high-density shadows of the lungs less than 3 cm in size, which appear rounded or rounded, and belong to the high-density lesions in the lungs. The two types of lesions are not the same and can be effectively differentiated by chest CT.
The causes of fibrotic foci and lung nodules are also different. Fibrotic foci are old foci, such as tuberculosis, pneumonia and other diseases, and if the scar produced by the above mentioned diseases can not be completely absorbed, fibrotic foci may appear; whereas lung nodules may be old foci, and they may also be caused by other diseases, such as pneumoconiosis, tuberculosis, benign tumors and other diseases, or even serious diseases, such as lung cancer or metastatic carcinoma of the lungs.
In short, fibrous foci differ from pulmonary nodules not only in their morphology, but also in their cause.