In recent years, hepatic, cardiac, and even pancreatic iron deposition has been studied in detail. However, the presence and incidence of iron disposition of normal-sized adrenal glands has not been adequately reported (1). The purpose of this study was to evaluate the levels of iron deposition in the adrenal glands in patients with iron overload. 8 Patients (age: 16-67 y) with transfusion dependent thalassemia (TDT: n=4), sickle cell disease (SCD, n=1), transfusion dependent rare anemia (DBA, sideroblastic anemia, n=3), , and one healthy control (age: 35 y) were studied at our units for clinical liver iron (LIC by biosusceptometry), relative cardiac, pancreatic, and adrenal iron assessment (by MRI-R2*/T2*). At 3.0 T (Ingenia®, Philips AG, Eindhoven, Netherlands), a breath-hold 3D multi-slice (n = 20, 8 mm, oversampling 1.5) data acquisition was used (TR = 24.3 ms, TE = 1.2-23.05 ms, t = 20 · 1.15 ms, flip angle = 3°, bandwidth 1425 Hz/pixel). In patients with suspected severe liver iron burden (LIC > 2000 µg/gliver), an additional 3D sequence with shorter echo times was used (TE = 0.65-16.93 ms, t = 20 · 0.86 ms). In vivo liver iron concentration (LIC, dry-weight conversion factor = 6) was noninvasively measured by SQUID biomagnetic liver susceptometry (BLS). R2* was determined from a mono-exponential fit to the echo-time dependent signal amplitudes (magnitude) averaged over a whole liver slice with constant signal level offset. For iron assessment in fatty tissue (pancreas, bone marrow) by MRI-R2*, chemical shift relaxometry with effective fat shift (1.5T: 213 Hz, 3.0T: 427 Hz) and equal R2* rates for water/fat was used as described elsewhere (2). Median adrenal R2* rates and aFC for patients with iron overload differed significantly from control. Highest adrenal R2* (313.4 s-1 and 389.4s-1) was found in DBA and one ß-thalssemia patients, respectively. Most of the patients (66/69) showed increased LIC 2798 ± 1846. The mean R2* was 175 ± 127 s-1 in patients, whereas the control had an R2* of 46.1 s-1. In all patients, fatty infiltration of the adrenal gland was above the range of controls (> 14.2%), whereas the mean aFC of 24 ± 9% were found in patients with the minimum value of 13.8% and a maximum value of 36.1%, showing the fatty infiltration within the glands. Adrenal R2* correlated with LIC (rs=0.52, p=10-4) (Figure 1) and the fat infiltration correlated with adrenal R2* (rS = 0.75, p < 10-4) (Figure 2)). A side difference between the right and the left adrenal gland was not detected (Figure 3). The intra-operator variability was not different from the inter-operator variability for experienced operators (10.4 ± 10.5% vs. 11 ± 10.4%). In the current study we demonstrated that MRI-R2* measurements can be adequately used for determining the relative iron distribution in the adrenal gland. Both iron and fat content in the adrenal gland could be evaluated with R2*. Besides iron accumulation, fatty degeneration might be an additional risk factor for the development of endocrinological disorder such as growth hormonal dysfunction, hypothyroidism, hypogonadism as well as adrenal insufficiency (3), and might also explain the early onset of these diseases in patients with iron overload. This hypothesis needs further investigation in asymptomatic patients.