Recent advances in the conservative treatment of the giant cavity.

A giant cavity is a huge excavation which involves the greater part of a lobe or a whole lobe. When it occupies more than one lobe, we do not speak of giant cavity but of lung emptying, “Vaciamento pulmonar.” There are two types of giant cavities; and their differentiation is important since the treatment varies with the type. The first is the inflated, hypertensive giant cavity with a check-valve mechanism whose volume depends on the function of this valve. The second is the giant cavity following the progressive destruction of the surrounding tissue. The Inflated cavity is not necessarily surrounded by infected lung tissue but can develop in almost healthy tissue, while the destructive cavity is necessarily surrounded by diseased tissue subjected to a more or less rapid process of destruction. While the differentiation between an Inflated and a destructive cavity is sometimes easy, it is frequently difficult. Radiologically, we can say that a cavity is valvular when it appears in tissue little affected by condensation and/or caseation. The volume quickly surpasses that of the Initial lesion; Its contour is spherical or oval with thin walls. The destructive cavity is also round until it reaches a certain size when It loses this characteristic and is molded by the thoracic wall, the fibrous tissue formation or other hard surrounding tissues. This type of cavity is surrounded by densely condensed tissue, partly diseased and partly compressed, which casts a heavy shadow. Usually this cavity has a slow progress, or it may progress rapidly in caseopneumonic process. It is seldom isolated and seldom corresponds to unilateral disease. On the contrary bilateral Involvement Is the rule. Clinical observations offer different data: The Inflated cavity is usually silent. The destructive cavity, surrounded by solid conductive tissue gives the typical cavity syndrome, with expiratory cavernous breathing, coarse rales associated with sibilant rales. However, sibilant rales may occasionally be found in inflated cavities. Radiologically we may observe the expansion of the cavity under