Whereas unilateral spontaneous pneumothorax is not infrequently encountered, a bilateral one is rarely encountered. However, one other case besides the one reported in this paper has been observed.* The case reported here was mentioned at a previous meeting of this society in a discussion of a paper by Graham, in 1923, relative to the experimental production of bilateral pneumothorax in dogs. It is remarkable that in these two human cases of bilateral pneumothorax, prompt recovery has resulted in spite of the collapse of both lungs (Fig. 1, A and B).
In spontaneous pneumothorax, either unilateral or bilateral, it is not safe to infer that complete expansion of one or both lungs will result. In two cases observed by me the lung failed to expand in each case. One case was observed for about a period of a year and the other case for a period of more than six years