Parenchymal band

Fig. 7.10. Prone thin-section computed tomography of an asbestos-exposed individual showing multiple parenchymal bands (arrows) arising from an area of pleural thickening...

Fig. 7.15. Thin-section computed tomography showing multiple parenchymal bands arising from a single point of thickened pleura likened to crow s feef (arrows)...

Fig. 8.15a,b. Computed tomography scan of the chest photographed in mediastinal (a) and pulmonary (b) window settings shows a small amount of remnant fluid within the right pleural cavity in a patient who had a benign asbestos pleurisy. Note the presence of bilateral calcified pleural plaques, and parenchymal bands and rounded atelectasis in the right lower lobe... 

With the recent extensive use of CT in asbestos-exposed workers, attention has been paid to lung involvement associated with pleural thickening in the form of parenchymal bands and rounded atelectasis that reflect the fibrosis of the visceral pleura (Solomon 1989 Cohen et al. 1993 Gevenois et al. 1998). These associated findings help us to distinguish visceral pleural fibrosis from parietal pleural plaques and have revealed that visceral pleural fibrosis can be focal. 

Fig.8.16. Postero-anterior chest radiograph shows bilateral diffuse pleural thickening with non-interrupted pleural density extending over at least one-fourth of the chest wall (large arrows), with parenchymal bands, particularly well visible on the right side (thin arrows), and bilateral costophrenic-angle obliteration...

Fig. 8.18. Lateral radiograph shows a posterior rounded atelectasis large arrow) associated with parenchymal bands thin arrows)...

Parenchymal bands consist of linear densities 2-5 cm in length, usually contacting the pleural surface and distinguishable from pulmonary blood vessels in that they are thicker, do not taper peripherally, and are often oriented in a direction incompatible with normal vessels (Fig. 8.21) (Aberle et al. 1988). 

Fig. 8.21. Computed tomography scan of the chest shows bilateral parenchymal bands associated with bilateral diffuse pleural thickenings...

In the subacute phase, arterial vascular enhancement peaks at 1-3 days. Large infarcts will also demonstrate meningeal enhancement that may represent reactive hyperemia, which peaks at 2-6 days. Both arterial and meningeal enhancement typically resolve by 1 week [11]. Parenchymal enhancement also occurs during this phase gray matter enhancement can appear band-like or gyriform (Fig. 6.5). This is secondary to disruption of the BBB and restored tissue perfusion from a recanalized occlusion or collateral flow. 

---