Scanning multiple slit assembly: a practical and efficient device to reduce scatter.

A scanning multiple slit assembly consisting of an array of long narrow beam-defining slits coupled with scatter-eliminating slots beneath the patient is a feasible, practical, and efficient method of reducing scatter and increasing contrast and image quality in diagnostic radiology. Measurements of the ratio of scattered-to-primary radiation transmitted by a scanning multiple slit assembly and a conventional high ratio grid under similar conditions showed the relative intensity of scatter transmitted by the slit assembly to be only one-third that of the grid. A noticeable improvement in contrast was obtained using the slit assembly, without increase in patient exposure. The design, construction, and clinical implications of such a scatter-eliminating technique are discussed.