Crippled lung: variations on a theme by Macleod.

We have studied nine male patients (age 18 to 68 years) with radiographic and physiologic evidence of an abnormally small lung on one side (three right and six left). All had had a childhood pneumonia or bronchiolitis and eight had chronic or recurrent bronchitis and exertional dyspnea. Radiography showed two of the small lungs to be hypolucent while seven were hyperlucent. Bronchography revealed evidence of bilateral chronic bronchitis in all with saccular bronchiectasis in three. Angiography showed strikingly diminished vascularity to the smaller lung. Spirometry revealed airway obstruction in seven of the patients. All had pulmonary arterial hypertension. Radiospirometry showed that the small lung had on the average 30% of the total ventilation but only 15% of the perfusion. Washout of 133 Xe was extremely slow in radiolucent regions. We suggest the name "crippled lung" syndrome for this entity because it is purely descriptive and encompasses several clinical variants. It also avoids the pitfalls of etiologic implication (acquired-congenital). Clinical or subclinical bronchitis seems to be common in these patients and the prime goal in therapy must be to combat the tendency towards airway infection.