• Based on Size <3cms

  • Single or Multiple
  • Macronodules
  • Micronodules

• Based on Shape

  • Round
  • Stellate or Spiculated

• Based on Position

  • Centrilobular

  • 

• Based on Character

  1. Solid
  2. Subsolid
  3. Ground Glass 
  4. Calcified

Lung nodules, by definition are less than 3 centimeters in diameter and are quite common. Lung nodules can be categorized based on their appearance, size, and other characteristics. The most common types of lung nodules seen on CT scans include:

Solitary pulmonary nodule (SPN): This refers to a single lung nodule that appears as a well-defined round or oval lesion in the lung tissue.

Solid pulmonary nodule: These nodules appear as well-defined, dense lesions with a uniform density throughout. They can be benign or malignant.

Multiple pulmonary nodules: Sometimes, more than one nodule can be present in the lungs. These can be caused by various conditions such as metastases from cancer or infectious diseases.

Ground-glass opacity (GGO): GGO appears as hazy, increased lung density that does not obscure the underlying bronchial structures. It can be a sign of various conditions, including early-stage lung cancer or inflammation.

1. Ground Glass Opacity and Adenocarcinoma with Lepidic Growth

The Ground Glass Opacity (GGO) in this case  is  caused by partial filling of the alveolus with malignant cells                                                                                                                                                        Ground glass opacification may be caused by partial filling of the alveolus with cellular material resulting in  partial replacement of air with solid material.  The net density is gray rather than white in the situation where the  alveolus is fully replaced with cells or fluid. There is blending of the black of the subtending airways and  the white of the vessels  with the gray density of the cellular infiltrate and hence the normal vessels are not visualized in ground glass opacities.

Part-solid nodule: Part-solid nodules have both solid and ground-glass components. These can also be associated with lung cancer, particularly adenocarcinoma.

 

Calcified nodules:

Some lung nodules may contain calcium deposits, causing them to appear as dense spots on the CT scan. These are often benign and can result from previous infections or scarring.

 

Cavitating Nodule

Pseudocavitation