Chronic hypercapnia and radiological changes in the pituitary fossa.

A consecutive series of ten patients with chronic bronchitis and hypercapnia were studied. All seven patients with chronic hypercapnia and one patient with intermittent hypercapnia showed evidence on skull radiographs of raised intracranial pressure. In five male and three female chronic bronchitics matched for age and ventilatory impairment, but without hypercapnia, no such radiological abnormalities were shown. The clinical significance and pathophysiology of this hitherto unreported finding is discussed. It would appear that in some cases the chronicity of hypercapnia may be diagnosed from a radiograph of the pituitary fossa.