Upper airway obstruction in infants and small children. Improved radiographic diagnosis by combining filtration, high kilovoltage, and magnification.

Selective filtration, high kilovoltage, and fine focal spot magnification produce detailed radiographs of the airway of infants and small children. This technique has been applied to the study of upper airway obstruction in the glottic, subglottic, and supraglottic areas. Its great diagnostic yield is accompanied by a reduction in radiation dose compared to that of a nonfilter technique. The physical factors dictating choice of filter and film-screen combination are discussed.