Haemochromatosis (pancreatic manifestations)
Pancreatic manifestations of haemochromatosis typically occur with primary haemochromatosis, as the organ is usually spared in the secondary form of the disease.
Iron deposition can occur in the pancreas with primary hemochromatosis. Pancreatic involvement is uncommon in patients without liver cirrhosis. Most cirrhotic patients with primary hemochromatosis have pancreatic iron deposition and may have type 1 diabetes mellitus.
Iron causes magnetic susceptibility artefact, which leads to spin dephasing (T2*-related signal loss). This dephasing results in decreased signal intensity on MRI images. Like the liver, the pancreas will be markedly hypointense on T2 weighted- and T1-weighted T2* gradient echo sequences.1,3
Dual sequences MR imaging (gradient in and out phase) demonstrates decreased signal intensity in the iron loaded tissues on the in-phase images compared with the out-phase images (opposite of what you would see with microscopic fat deposit as in hepatic steatosis). This occurs because the echo time of the in-phase sequence is usually higher than that of the out-phase sequence; therefore, the in-phase pulse sequence is more sensitive to iron deposits because of the increased T2* effect 2.
- 1. Weissleder R, Wittenberg J, Harisinghani MMGH et-al. Primer of Diagnostic Imaging. Mosby. (2011) ISBN:0323065384. Read it at Google Books - Find it at Amazon
- 2. Youssef DM, Fawzy Mohammad F, Ahmed Fathy A et-al. Assessment of hepatic and pancreatic iron overload in pediatric Beta-thalassemic major patients by t2* weighted gradient echo magnetic resonance imaging. ISRN Hematol. 2013;2013: 496985. doi:10.1155/2013/496985 - Free text at pubmed - Pubmed citation
- 3. MR Imaging of the Body. Thieme. ISBN:3131358416. Read it at Google Books - Find it at Amazon