Fig. 8From: Pulmonary alveolar proteinosis in a catScanning electron microscopic image of the alveolar content. a Negative backscattered electron image obtained with the scanning electron microscope in an area of proteinosis shows dark particles within the respiratory size range, ie less than 5 nm (magnification × 2400). b At higher magnification (x4000) the black particles appear angulated and fragmentedBack to article page