Stereozonography in Mediastinum and Pulmonary Hilum using A Compensating Filter and Computed Radiography

In the case of chest tomography, particularly the mediastinum and the pulmonary hilar tomography are difficult to the matter without exposure time factor. For the reason, these region are much used rectilinear tomography for the shortening of exposure time. But, as for the visuability of the morphology, it is advisable for these region to use in multi-directional tomography. However, it is in need of long exposure time. Therefore, authours experimented with stereozonography of short exposure time by circular movemant using a compensating filter and computed radiography. Shifting distance of Xray tube for stereofraphy was 10% of distance between focus and object. The exposure time and exposure angle were 0.6 sec, 2θ=3° respectively. As a result, this stereozonography was excellent in the visuabilities of mediastinal region, including bronchovascular shadows, and could examine in details is on images of these region. My using the compensating filter, the improved image guality of mediastinal region was obstained. On addition, using computed radiographic system, even if artifact araised from disagreement between from of the computed radiographic system, even if artifact araised from disagreement metween form of rhe compensating filter and mediastinal region, authors could easily restored non-diagnostic image by orverall density manipulation and unsharp mask piltering.

Stereozonography

Mediastinum and Pulmonary hilum

Compensating filter

Computed radiography