Fig. 2.11.

Aspiration pneumonia, TBBx. (a) Intermediate magnification photomicrograph showing BOOP with granulomatous inflammation (hematoxylin and eosin, original magnification ×200). Multinucleated giant cells are engulfing aspirated exogenous substances. The amorphous pale-staining material within the upper giant cell (arrow) is partially digested foodstuff while the birefringent, cracked, crystalline material in the lower giant cell (asterisk) is microcrystalline cellulose, a common inorganic filler utilized in oral medications. (b) Polarized light microscopy can be helpful in identifying and/or confirming polarizable substances in suspected cases of aspiration (hematoxylin and eosin, original magnification ×600). Certain crystalline fillers, such as microcrystalline cellulose (as seen here) are strongly polarizable. Plant cell walls from aspirated foods vary greatly in their strength of polarization