Possibilities and Benefits of Tin Filtering in MSK Radiology

Introduction Modulation of the radiographic spectrum by a tin filter implemented by a computed tomography (CT) manufacturer enables new approaches in CT imaging that can contribute both to dose reduction and to the improvement of image quality. The use, benefits, and also the possible pitfalls are discussed.

Material and Methods A summary of the results of our working group of the past 2 years illuminates the application possibilities, the effect, and the use of tin prefiltration in CT diagnostics, in particular in musculoskeletal (MSK) radiology. The possibility of dose reduction, the importance of low-dose CT protocols (e.g., pelvic imaging), and the benefit for the reduction of metal artifacts (orthopaedic implants) were investigated.

Results The use of the tin filter can contribute to a significant dose reduction in MSK radiology. Especially low-dose CT with a tin filter can significantly reduce the effective dose while still maintaining very good diagnostic accuracy. The hardened radiation beam with its homogeneous and more penetrating radiographic spectrum also enables very good imaging of metal implants and is superior to dual-energy computed tomography in this respect. However, the hard radiation results in a lower image contrast.

Conclusion The use of a tin filter in CT imaging opens up new possibilities that can contribute to a significant improvement in MSK radiology, in particular dose reduction and artifact reduction in metal artifacts. The advantages far outweigh the disadvantages associated with a tin filter.

No conflict of interest has been declared by the author(s).