CLINICAL HISTORY.—Figure 1 is a chest roentgenogram of an asymptomatic 6 8/12-year-old white girl who was seen because of asymmetry of the chest. Physical examination showed the absence of the left pectoralis major muscle. No abnormalities of the upper extremities were noted by inspection or roentgenograms. Chest roentgenograms were obtained to evaluate the bony thorax for associated abnormalities.
Figure 2 is a chest roentgenogram of a 7-month-old asymptomatic white boy. He was seen for evaluation of asymmetry of the chest and absence of the breast on the right side. Physical examination showed the absence of the right pectoralis major muscle and the right breast. No abnormalities of the upper extremities were noted by inspection or roentgenograms. Chest roentgenograms were obtained to evaluate the bony thorax for associated abnormalities.
Denouement and Discussion
Absence of Pectoralis Major MuscleUnilateral hyperlucent lung in children may be caused by a number of processes. The