Abnormal "hair-like" filaments in chronic maxillary sinusitis . A scanning electron microscopic investigation.

Scanning electron microscopic investigations were performed on the maxillary sinus mucosa of five healthy persons and seven patients with chronic maxillary sinusitis. The occurrence of previously undescribed hair-like filaments in one case of chronic maxillary sinusitis is presented. These abnormal filaments are much longer (about 50--60 micron) and thinner (about 0.08 micron) than normal kinocilia (about 0.2 micron thick and 5--7 micron long), thus exhibiting a hair-like appearance. As the microvilli (cytofila) in maxillary sinus mucosa have the same thickness (about 0.08 micron), these hair-like filaments could be regarded as abnormally long microvilli. The possible significance of these abnormal filaments is discussed.