fibrosn), pleura (pleural effusion), heart (congestive cardiac failure), chest wall (kyphcsis).

abdominal cavity (ascites) are common diseases known for their ability t0 reduce VC Utility of the VC measurement VC is often of prognostic value (ii) it gives also an idea about the progress of a chronic disease Thus, in a case of emphysema, gross, reduction of VC isof unfavourable prognosis Or, in the same case of emphysema, over a few years, if the VC shows prgressive detenoration, the physician understands that the taease is steadily progressing (iii) In assessment of physical fitness. VC is of some help Thus in highly physically fit perrsons (sportsmen) VC is high, and vice versa Timed vital capaciy In early stages of many chronic diseases, e. o emphysema. the volume of VC may remain withim normal limits but the Timed vital capacity may show