Small nodular foci in the lower lobe of the lung are most often seen as old lesions caused by chronic lung infections. The presence of small nodular foci requires further evaluation of the size and nature of the small nodular foci. If the small nodular foci show ground glass, partially solid nodules and solid nodular changes, it is more important to know the nature of the 3 conditions specifically. If the ground glass nodule is smaller than 5 mm it is mostly benign, and if it is larger than 8 mm with lobulated, short burrs, the small nodule is mostly malignant. If some of the solid nodules are larger than 8 mm, the possibility of early lung cancer should also be highly suspected. Small nodules in the lower lobe of the lung are also seen in tuberculosis with chronic lung infections, as well as in people who work in long-term smoking and dusty jobs, such as masons and coal mines, who are also prone to small nodular changes in the lower lobe of the lung. Once a small nodular foci in the lower lobe of the lung are present, further chest enhancement CT examinations are needed to further evaluate whether the nodules are benign, malignant occupancies or tumors.