Non-invasive assessment of tissue iron overload.

In recent years, there has been increasing interest in non-invasive iron measurement, especially of the liver and heart, in patients with iron overload. Serum ferritin still remains an essential monitoring parameter in intervals between liver iron measurements; however, confounding factors such as inflammation, chelation treatment changes and the specific disease have to be taken into account. Liver iron measurements can now routinely be performed in clinical applications either by quantitative magnetic resonance imaging (MRI) using the transverse magnetic relaxation rate R(2) or R(2)* (1/T(2)) or by biomagnetic liver susceptometry. For iron measurements in the heart, the single-breathhold multi-echo MRI-R(2) method has become a standard modality and is now applied in clinical settings beyond research studies. In other tissues like the pancreas, pituitary, and brain, different MRI methods are employed, but their clinical benefit has yet to be proven.