Gradual expansion of a lung bulla is common and may be associated with
debilitating pulmonary symptoms. The aetiology of bulla expansion is
unclear. Spontaneous regression, on the other hand, is rarely observed
. The case is presented of a man in whom near complete spontaneous res
olution of a giant pulmonary bulla occurred, This event was associated
with dramatic improvement in the radiographic picture and pulmonary f
unction.