http://v.youku.com/v_show/id_XMTQwNzgxNTM4NA==.html?from=y1.7-1.2 Case Interpretation Video “Expert Consensus on Imaging Management of Pulmonary Subsolid Nodules” (2015) Key Points With the improvement of CT resolution, reduction of radiation dose, popularity of lung cancer screening and people’s health care awareness With the improvement of CT resolution, the decrease of radiation dose, the popularization of lung cancer screening and the increase of people’s health care awareness, more and more asymptomatic intra-pulmonary nodules are detected with smaller and lighter density. These nodules often lack characteristics and are difficult to diagnose, but they often lead to patient anxiety and clinical management is diverse, randomized and irregular. Zhang Keyun, Department of Radiology, Wuxi Eighth People’s Hospital I. Definition
Ground glass shadow (GGO) refers to a well-defined or indistinct intra-pulmonary hyperdense shadow on CT, but the lesion is not dense enough to obscure the traveling blood vessels and bronchial shadow therein. If the lesion is limited, it is called a focal ground glass shadow (fGGO); if the lesion is well-defined, round or round-like, and appears nodular, it is called a ground glass nodule (GGN). gGOs are divided into two categories based on internal density: if the lesion contains no solid components, it is called a pure ground glass shadow (pGGO); if it contains solid components, it is called a mixed ground glass shadow (mGGO). The corresponding GGN is also divided into pure GGN (pGGN) and mixed GGN (mGGN) according to the presence or absence of solid components, and the latter is also called partially solid nodules. All pulmonary nodules containing ground glass density (pGGN, mGGN) are called subsolid pulmonary nodules.
Imaging methods 1. X-ray: X-ray plain films are of limited value for detecting and showing GGN. 2. 2. CT: CT is the preferred method to show GGN. 3. MRI: MRI is not currently recommended for GGN. 4. PET-CT: PET-CT has limited diagnostic value for GGN lesions. (1) pGGN, PET-CT is not recommended. (2) mGGN with solid component <5mm, PET-CT is not recommended. For >5mm, PET-CT examination may be recommended if characterization is difficult. (4) For mGGN lesions with a high suspicion of malignancy and a solid component >5mm, a whole-body PET-CT examination for preoperative staging may be recommended. (5) PET-CT is recommended for patients with GGN accompanied by other solid nodules in the lung or with a history of extra-pulmonary malignancy. III. Differentiation of benign and malignant GGN (This consensus was published in the Chinese Journal of Radiology, Vol. 4, 2015. For a full and detailed understanding, please see the full article)