An unusual cause of dyspnea in a 77-year-old man.

Vital signs were normal except for an increased respiratory rate of 24 breaths/min. An examination of the lungs revealed reduced breath sounds over the right lower zone. Close observation of the breathing pattern revealed neither paradoxical abdominal wall movement nor obvious decreased expansion of the right side of the chest in the supine position. A neurologic examination revealed muscle weakness in the right upper extremity, atrophy of the intrinsic right hand muscles, and paresthesias in a C6 distribution (ie, paresthesia on the lateral aspect of the forearm from the elbow crease to the thumb, as well as the thumb, the index finger, and one half of the middle finger). The findings of examinations of the cardiac and other systems were normal. Laboratory Findings