Table 1.
Tabulated MRI parameters.
Table 2.
Characteristics of the study population.
Fig 1.
The T1-weighted image 1 (with magnification on the left) shows a patient case example of a 21-year old woman with indistinct stomach pains, but without diagnosis of physical disorders, who was examined at 3T. The patient was revealed to have a fatty liver with hyperintensity on the T1-weighted sequence. The T1 weighted image 2 (with magnification on the left) shows the corresponding normal weight control (22 years, female, no diagnosis), who was also examined at a field strength of 3T, but who does not show any sign of fatty liver and no hyperintensity on the T1-weighted image. The T1-weighted image 3 (with magnification on the left) shows a patient case example of a 27-year old woman with Crohn’s Disease, who was examined at 1.5 T. The patient was revealed to have a fatty liver with hyperintensity on the T1-weighted sequence. The T1 weighted image 4 (with magnification on the left) shows the corresponding normal weight control (29 years, female, Crohn’s disease), who was also examined at a field strength of 1.5 T, but who does not show any sign of fatty liver with a normal liver signal on the T1-weighted image. The left part of the figure shows the corresponding T2 images without (1a, 3a) and with (1b, 3b) fat saturation, revealing a relative signal loss of 36% (1b) or 23% (1b).
Fig 2.
Association between apparent liver fat content and BMI.
Association between apparent liver fat content and BMI for cases and controls, displayed by a scatter plot with linear regression line and corresponding 95% confidence interval (adjacent grey area). Cases are represented by green dots (dark green for 1.5T, light green for 3T), while controls are indicated by blue dots (dark blue for 1.5T, light blue for 3T). The liver fat content appears to be higher in patients with underweight BMI range than in patients with normal BMI range.
Fig 3.
Differences in percentage relative liver fat content between underweight individuals and normal weight controls.
This figure refers to a subgroup of underweight individuals (n = 12) without inflammatory bowel disease and visualizes the differences in percentage relative liver fat content between cases and controls and also between the observers. It can be seen, that there is a clear difference between cases and controls, with cases showing a significantly higher percentage liver fat content. There are no significant differences between the two observers.
Table 3.
Disease-related medical and surgical therapy.
Fig 4.
Association between various laboratory values and BMI for cases and controls. Cases are represented by red dots, while controls are indicated by blue dots. The blue graphs correspond to linear regression lines, while the adjacent grey areas represent the 95% confidence intervals. The limits for the laboratory values are as follows: Albumin (Alb): 35–52 g/L; alanine aminotransferase (ALT): women—< 31 U/L, men—< 41 U/L; alkaline phosphatase (AP): women– 35–105 U/L, men– 40–130 U/L; aspartate aminotransferase (AST): women < 35 U/L, men <50 U/L; total bilirubin (Bilirubin) < 1.2 mg/dl and gamma-glutamyltransferase (GGT): women– 5–36 U/L, men– 8–61 U/L.; CRP < 5 mg/L. In the graphs the limits for women are marked by the black dotted lines, while the limits for men are marked by grey dotted lines. For laboratory values without sex-specific values, only black dotted lines are used.
Fig 5.
Distribution of laboratory values.
Laboratory values as mean percentages of the upper limit of normal with the corresponding standard deviations, including Albumin, ALT (Alanin transaminase), AP (Alkaline phosphatase), AST (Aspartate aminotransferase), Bilirubin, CRP (C-reactive protein) and platelets. Especially CRP, ALT and platelets show increases above 100% of the upper limit of normal. For ALT, AST and AP, there were significant differences between cases and controls (p<0.05), with each case showing higher laboratory values compared to controls, although most of them remained within normal limits.
Table 4.
Analysis of potential differences between case/control group regarding laboratory values.
Fig 6.
Bland-Altman plots for the assessment of interobserver variability for percentage relative signal loss on the fat saturated T2 weighted images (percentage liver fat content) between cases and controls and at different field strengths. The mean ratio of the data is graphed with the centre line. Upper and lower reference lines show the upper and lower limits of agreement (95% prediction intervals).