Purpose To explore the cross-sectional and longitudinal relationships between fractional liver fat content liver volume and total liver fat burden. 0.001 follow-up) and between TLFI and liver volume (R2 = 0.352/0.452 < 0.001/< 0.001). Longitudinal analyses revealed statistically significant associations between liver volume change and liver mean PDFF switch (R2 = 0.556 < 0.001) between TLFI switch and liver mean PDFF switch (R2 = 0.920 < 0.001) and between TLFI switch and liver volume switch (R2 = 0.735 < 0.001). Conclusion Liver segmentation in combination with MRI-based PDFF estimation may be used to monitor liver volume liver imply PDFF and TLFI in a clinical trial. [23 44 20 45 The processing steps explained above are illustrated in Physique 1. It required each reader about 20 moments per case to perform the processing. The exact occasions were not recorded. Fig. 1 (a) Manual segmentation of liver contour in the upper half of the liver performed around the first echo. (b) The segmentation was propagated to co-registered slices at five other echo occasions. (c) The corresponding segmented images were generated for the 6 ... TLFI Calculation The TLFI (models: % ? mL) was calculated as the product of liver volume and liver mean PDFF: is the total segmented liver volume is the total number ZM 323881 hydrochloride of voxels in the segmented volume and PDFFi is the PDFF in the ith voxel. This is mathematically equivalent to the integration of the excess fat content in each voxel defined as the product of voxel volume and voxel PDFF over the entire liver volume. Intra- and inter-observer agreement To estimate intra- and inter-observer agreement of liver volume liver imply PDFF and TLFI measurements the image analyst and radiologist independently segmented 10 examinations from 5 cases randomly selected. Repeated segmentation was performed one week later using identical methods. Observers were blinded to their first measurement results and the results of the other observer. Liver biopsy and histopathological analysis Liver biopsy was performed as part of the clinical trial to which the present study is usually ancillary. Steatosis lobular inflammation hepatocellular iron fibrosis steatohepatitis and NAFLD activity score were scored by a single expert hepatopathologist using the NASH Clinical Research Network histologic scoring system ZM 323881 hydrochloride . Statistical Analysis Statistical analyses were performed using SPSS version 19.0 (SPSS Chicago Ill). Baseline characteristics Study subjects’ demographic laboratory imaging and histologic information were summarized as previously explained [research omitted for submission to maintain blinding to authors]. Categorical variables were expressed as figures and percentages. Continuous variables were expressed as mean (± standard error). Liver volume liver mean PDFF and TLFI Linear regression was used to evaluate the cross-sectional associations at baseline and at follow-up between the three variables (liver volume liver mean PDFF and TLFI) as well as the longitudinal associations between the ZM 323881 hydrochloride changes from baseline to follow-up in these three variables. Reader agreement The agreement PTK2 between and within readers for liver volume liver mean PDFF and TLFI was reported according to the Bland-Altman method as bias ± 1.96 standard deviations (SD) of the differences followed by the 95% limits of agreement interval. ZM 323881 hydrochloride Group comparison Comparisons within treatment groups were made using paired t-tests. Comparisons between treatment groups were made using independent sample t-tests assuming equivalent variance for continuous/ordinal variables and Fisher’s exact test for categorical variables. A two-tailed value ≤ 0.05 was considered statistically significant. RESULTS Clinical Characteristics Twenty-four (55.8%) of forty-three patients were men. The mean ± SD age was 48 ± 11.7 years. The mean body mass index was 31 ± 4.8 kg/m2. Eighteen (42%) of 43 patients were Caucasian 12 (28%) Hispanic eight (19%) Asian and three (7%) multi-racial. Both combined groups had equivalent baseline characteristics as shown in Table 1. Imaging Features At baseline topics got a mean liver organ level of 1918.9 mL (range: 1139.7-3146.7 mL) a mean PDFF of 16.6% (range: 5.2-31.8%) and mean TLFI of 323.2 %?mL (range: 93.5-685.8 %?mL). ZM 323881 hydrochloride Cross-sectional analyses As summarized in Statistics 3 and ?and4 4 cross-sectional analyses at both baseline with follow-up uncovered a weak positive relationship between liver quantity and liver suggest PDFF (R2 = 0.022 to 0.107 = .045 to .369) but statistically significant positive moderate or strong relationships between TLFI and liver.