PCD-CT methods for liver fat quantification (HU-FF and SPP-FF) showed moderate correlation with MRI-derived fat fractions (r = 0.40-0.71, P < .05) in a cohort with low liver fat.
Observational (n=42)
Does liver fat quantification using PCD-CT agree with MRI-derived fat fractions in patients without liver disease?
In patients with low liver fat, PCD-CT methods for liver fat quantification show only moderate correlation and considerable variation in agreement with MRI.
Effect estimate: r = 0.40-0.71
p-value: p=< .05
RATIONALE AND OBJECTIVES: To evaluate the agreement of different liver fat quantification methods using Photon-Counting-Detector (PCD)-CT via virtual non-contrast (VNC) reconstructions and dedicated spectral post-processing algorithms, with MRI-derived fat fractions (FF) serving as the reference standard. MATERIALS AND METHODS: This retrospective study included consecutive patients who underwent abdominal PCD-CT in arterial (art) and portal-venous (pv) phases and abdominal multiparametric MRI with chemical shift imaging between February 2022 and May 2024. Patients were excluded if no arterial phase was available or if chronic or acute liver disease was present. Liver FF was quantified using two methods in both contrast phases: via Hounsfield units from VNC images using an established formula (HU-FF), and directly using a spectral post-processing algorithm (SPP-FF). These were compared among themselves and to MRI-FF using Pearson's correlation and mean absolute error (MAE). RESULTS: The final cohort included 42 patients (mean age, 66.9 ± 11.4 years; 50% male). Median MRI-FF was 1.49% (Interquartile Range IQR, 0.72%-4.57%). HU-FF and SPP-FF showed moderate correlation with MRI-FF (r = 0.40-0.71, P < .05). Correlation between HU-FF and SPP-FF was high (r = 0.72-0.80), with excellent intra-method agreement (HU-FF: r = 0.94; SPP-FF: r = 0.93). MAE was lowest for SPP-FF-art (3.30%) and highest for HU-FF-pv (4.82%). CONCLUSION: PCD-CT offers several methods for liver fat quantification, yet, in a cohort with low liver fat, agreement with MRI varied considerably.
Klemm et al. (Mon,) conducted a observational in Normal to minimal hepatic fat (n=42). Photon-Counting-Detector (PCD)-CT liver fat quantification (HU-FF and SPP-FF) vs. MRI-derived fat fractions (MRI-FF) was evaluated on Agreement of liver fat quantification methods (Pearson's correlation and mean absolute error) (r = 0.40-0.71, p=< .05). PCD-CT methods for liver fat quantification (HU-FF and SPP-FF) showed moderate correlation with MRI-derived fat fractions (r = 0.40-0.71, P < .05) in a cohort with low liver fat.