Improved Beam-hardening Reduction in CT - Impact on Image Quality and Diagnostic Certainty in Emergency Imaging of the Brain.

RATIONALE AND

OBJECTIVES

To assess the impact of an optimized beam-hardening artifact reduction algorithm on image quality and diagnostic certainty in emergency unenhanced brain CT.

MATERIALS AND

METHODS

Retrospective study of consecutive patients referred for unenhanced brain CT to rule out traumatic brain injuries in 2023. Images were reconstructed using both (A) a standard and (B) an optimized iterative beam-hardening correction algorithm (iBHC). CT attenuation, image noise and SNR were measured in the cortex of supratentorial and infratentorial regions and in the pons. Posterior Fossa Artifact Index (PFAI) and Subcalvarial Artifact Index (SAI) were calculated. Two neuroradiologists and two emergency radiologists independently compared artifacts and diagnostic certainty between both algorithms using 5-point Likert scales and side-by-side comparisons. A paired Wilcoxon-test with correction for multiple testing was used.

RESULTS

100 consecutive patients (55 women; 64.1 ± 20 years) were included. CT attenuation was significantly lower for B (all P <.0001). SNR was significantly lower supratentorial (frontal region: 10.5 vs. 12.9, P<.0001) and significantly higher in the pons (5.9 vs. 5.5, P <.0001) for B. PFAI was significantly reduced for B (5.5 vs. 6.4, P <.0001), while there was no significant difference in SAI (P = 0.304). The optimized algorithm was selected as superior in 100%, 100%, 99%, 99% of supratentorial and in 100%, 99%, 99%, 86% of infratentorial cases for readers 1 to 4, respectively.

CONCLUSION

An optimized iBHC algorithm demonstrated significantly improved image quality, reduced artifacts and improved diagnostic certainty in emergency unenhanced brain CT.