<unk>  as a clinico-pathological entity can be defined in two ways. Morphologically, it is a pathologic collection of blood within the pleural cavity, between the lung surface and inner chest wall.  Clinically ,<unk>  is defined as a pleural fluid with a hematocrit ranging from at least 25–50% of peripheral blood. In cases of long standing<unk>  due to haemodilution,<unk>  can appear with lower levels of hematocrit. massive<unk>  is defined as the drainage of more than 1500 cc of blood upon chest tube insertion.
Hemothorax
Urinothorax
Chylothorax
Pulmonary hematoma
Hydropneumothorax
Hemopneumothorax
Pneumothorax
Round pneumonia