Khadjidja,
I am not a doctor, but here is what i found for you:
"A lung lesion is abnormal tissue found on or in a person’s lung. It can be the result of an infection or illness, which may clear up without causing the patient long-term problems. For example, some lung lesions develop because of tuberculosis or pneumonia infections."
If you have any lung disease (such as tuberculosis), the lesions (small cracks) are visible at the chest x-ray. If you were healed, they will be called inactive lesions, and if the disease is present, they will be active.
The doctor should know if there is anything wrong with your lungs and tell you so. If there is nothing wrong, the paper should read no lung lesions present.
Maybe you should see another doctor who would be able to understand the terms?