Digital image composition in long-leg radiography with a flat-panel detector: first clinical experiences.

RATIONALE AND OBJECTIVES

The purpose of this study was to evaluate the image quality of composed long-leg examinations with a large-area, flat-panel x-ray detector.

METHODS

Thirty-five consecutive patients were included in this study. All images were obtained with a kilovoltage setting identical with conventional radiographies of speed class 400; amperage values were reduced by 50% compared with standard dose. After acquisition, the images were transferred to a workstation where the whole image was reconstructed using a generalized correlation method. Images were presented to 3 observers. Examination quality was ranked on a 3-point scale: 1 = no manual adjustment necessary; 2 = composition required manual correction; 3 = no composition possible.

RESULTS

Patient rankings were 31/35 (88.6%) in category 1, 3/35 (8.6%) in category 2, and 1/35 (2.8%) in category 3 (primarily due to an application error).

CONCLUSIONS

The analysis of the first clinical examinations of long-leg radiographies with a 43 cm x 43 cm flat-panel detector demonstrates very good reliability of the digital image composition.