Is glass visible on plain radiographs? A cadaver study.

Eighteen randomly selected pieces of nonleaded glass from a collection of 30 pieces from broken bottles of four known color types found on the streets of Houston were sorted into four sets with one control. The purpose of this study was to determine if regular glass is visible on plain radiographs and whether color, location, or volume of these fragments had any effect on the detection of nonleaded glass. These sets were then placed into a fresh-frozen cadaver foot and ankle with a history of insulin-dependent diabetes and peripheral vascular disease. This foot was radiographed utilizing four standard foot projections. Five examiners read these five sets of radiographs twice and recorded the number seen. Overall sensitivity for all of the examiners was 90% with an overall false-positive rate of 10%. Intraobserver and interobserver Pearson's correlation coefficients showed that there was reliability between the first and second readings and between observers. The authors concluded that regular nonleaded glass is radiographically visible and that factors such as color and location of the glass have no effect on its detection, while a volume of less than 15 mm3 may have an effect on the detection of glass.