Stereoscanning electron microscopy of argon laser excised laryngeal papilloma.

Laryngeal papillomas were removed from two patients with the argon laser and examined by transmission electron microscopy (TEM), scanning electron microscopy (SEM), and stereoscanning electron microscopy (SSEM). Two techniques, lipid-carbohydrate retention for TEM specimens and sonication for SEM, were applied in studying the papillomas. Lipid-carbohydrate retention results were in agreement with previous work in papilloma ultrastructure. The char interface was observed with the sonication technique. Peripheral to the laser impact site, four zones were observed: 1. coagulation necrosis, 2. contracted epithelial cells, 3. minimally damaged epithelial cells, and 4. morphologically undamaged epithelial cells. In Zone 2, cells were violently popped-off as heat was conducted through the epithelium. The potential for spread of papillomas is discussed and suction of the vapor plume recommended when removing laryngeal papillomas with the argon laser.