Figure 5d. PCH in a 22-year-old woman. (a) Posteroanterior chest radiograph shows a prominent central pulmonary artery (arrow) and faint nodular opacities, best seen in the lung bases. (b) Radiograph collimated to the right lower lobe reveals widespread, poorly circumscribed nodular opacities (arrowheads). (c) Axial CT image (lung window level) collimated to the right lower lobe shows well-circumscribed ground-glass nodules (arrowheads) and no septal lines. (d) Photograph of the visceral pleural surface reveals multiple petechial-appearing nodules (arrow), just visible beneath the pleura, that actually represent the angiomatous lesions of PCH. (e) Low-power photomicrograph (original magnification, x1; hematoxylineosin [H-E] stain) shows multiple discrete parenchymal nodules (arrowheads). (f) Low-power photomicrograph (original magnification, x4; H-E stain) shows a discrete parenchymal nodule (arrowheads) abutting the visceral pleura.