The signs of cavity in the lung, both on physical and roentgenologic examination, have always been a matter of interest and inquiry. The present paper aims to give added information on the subject, based, partly, on the examination and observation of a large number of cases in a tuberculosis hospital.
Some years ago my attention was drawn to shadows in roentgenograms suggesting cavities, although no physical signs of cavity formation were present, and for a considerable length of time the failure to substantiate by roentgenologic means cavity signs obtained on physical examination has been noted.
This inquiry covers cases with definite cavity formation and its classical signs, cases giving fair clinical evidence of cavity but not proven by roentgenologic methods, and cases giving certain roentgenologic images ranging from true cavity formation to simple pleural thickening, without clinical evidence.
Obviously, the reason for the more frequent occurrence of cavity formation