ABSTRACT
PURPOSE: To evaluate in-phase and out-of-phase magnetic resonance (MR) imaging in the estimation of liver fat content (LFC) in patients with nonalcoholic fatty liver disease (NAFLD), with hydrogen ((1)H) MR spectroscopy as the reference standard. MATERIALS AND METHODS: Written informed consent was obtained from all subjects, and the local ethics committee approved this prospective study protocol. A total of 33 patients with type 2 diabetes mellitus who were at high risk for NAFLD (23 men, 10 women; overall mean age, 62.8 years +/- 8.3 [standard deviation]; age range, 48-77 years) underwent 1.5-T MR imaging with (1)H MR spectroscopy and in-phase and out-of-phase imaging of the liver. Three fat indexes were calculated from the signal intensity (SI) measured on the images. Two radiologists independently graded SI changes between in-phase and out-of-phase images by means of visual inspection. The Pearson correlation coefficient was used to study the relationship between the obtained parameters of SI change and LFC measured with (1)H MR spectroscopy. RESULTS: Fat indexes calculated from in-phase and out-of-phase images correlated linearly with LFC measured with (1)H MR spectroscopy (P < .001, r = 0.94-0.96) and were superior (P = .004) to visual estimates (P < .001, r = 0.88). The simple difference in SI between in-phase and out-of-phase images was used to calculate the fat index. An intercept of the regression line with the x-axis was observed at 5.1%, discriminating between normal and elevated LFC with high sensitivity (95%) and specificity (98%). CONCLUSION: In-phase and out-of-phase imaging can be used to rapidly estimate the LFC in patients with NAFLD. The cutoff value of 5.1% enables objective rapid and reliable discrimination of normal LFC from elevated LFC.
Subject(s)
Diabetes Mellitus, Type 2/diagnosis , Fatty Liver/diagnosis , Image Enhancement/methods , Image Processing, Computer-Assisted/methods , Liver/pathology , Magnetic Resonance Imaging/methods , Magnetic Resonance Spectroscopy/methods , Aged , Diabetes Mellitus, Type 2/pathology , Fatty Liver/pathology , Female , Humans , Male , Middle Aged , Reference Standards , Sensitivity and Specificity , SoftwareABSTRACT
In this study, we evaluated and compared the value of spiral computed tomography, transabdominal ultrasonography, laparoscopy, and laparoscopic ultrasonography in staging gastric cancer in 37 patients; there was a special interest in the additional information provided by laparoscopic ultrasonography. Although laparoscopy was unreliable or hindered by adhesions in 11% of the patients, the benefit of laparoscopy for staging was evident especially for the detection of peritoneal carcinomatosis that was missed by the other diagnostic modalities. Laparoscopic ultrasonography did not change the stage of the disease nor the decision whether to proceed with laparotomy for any of the patients. The decision whether to proceed with laparotomy was correctly predicted in 95% of the cases.
