MR imaging of the liver and complicating hepatic tumors in type Ia glycogen storage disease

Background A study to determine the usefulness of magnetic resonance imaging (MRI) of the liver in patients with type Ia glycogen storage disease was performed. Methods T1-weighted images and T2-weighted images were obtained with spin echo technique in 4 patients with type Ia glycogen storage disease. The T2 values for the liver parenchyma of these 4 patients, and for the complicating liver tumors in 2 of these patients, were measured. One patient underwent hepatic angiography. For each patient with liver tumors, the number, size, and MRI findings of the tumors and their signal intensity were compared to that for the liver parenchyma on both T1-weighted and T2-weighted images. Results There was a slight reduction of T2 relaxation time in the liver parenchyma. Complicating liver tumors were depicted as high-intensity areas on T2-weighted images. The mean T2 value for diseased liver parenchyma was 34.5 milliseconds, and for liver tumors, 41.5 milliseconds. The former was less than the value for normal liver parenchyma. Reduction of T2 relaxation time for diseased liver parenchyma was probably due to the regulation of proton movement by macromolecular glycogen granules. All complicating liver tumors were depicted as high-intensity areas, compared to the diseased liver parenchyma. Conclusion These findings suggest that MRI can be useful for the observation of type Ia glycogen storage disease and complicating liver tumors.