Q: How you define Bulla(e) and Giant bulla(e) in lung?

Answer:

Bulla(e): Larger than 2 cm in distended state

Giant bulla(e):  Bulla larger than one third of the hemithorax size and compression of adjacent lung parenchyma

Reference:


Waseem M, Jones J, Brutus S, et al. Giant bulla mimicking pneumothorax. J Emerg Med 2005;29:155-158.