Correlations of Microradiographic and Histological Findings in the Pulmonary Vascular Bed

Abstract

Obstruction within pulmonary arteries is a well-known cause of pulmonary hypertension in patients with congenital heart disease, but dilatation of the pulmonary vessels is less well understood. The present report has shown that the technique of microradiography is well suited to the study of dilation of the pulmonary microcirculation because (1) vessels as small as capillaries are resolved, (2) whole capillary networks are seen in relation to the arteries feeding them and to the alveoli, and (3) the radiographed tissue may [See Figure in the PDF File] then be sectioned and stained for direct comparison of the histological and microradiographic aspects. The present study demonstrated the technique in a case of normal lungs, one of pulmonary hypertension and a high pulmonary blood flow, and in one of pulmonary hypertension and high pulmonary vascular resistance. Dilated capillaries were demonstrated in both patients with pulmonary hypertension. Greater distortion of the microvascular pattern was seen in the patient with high vascular resistance. Correlation of radiographic and histological examination provides an additional tool for study of the normal and abnormal pulmonary circulation.