What does ill-defined mean on a ct scan?

"Ill-defined" on a CT scan refers to a lesion or abnormality that lacks clear, distinct borders, making it difficult to determine its exact size, shape, or extent. This characteristic can indicate a more aggressive or infiltrative process, such as certain types of tumors or infections, as opposed to well-defined lesions, which are often more benign. The ill-defined nature may raise concerns for differential diagnoses and typically warrants further investigation or follow-up imaging.