Secondary Iron Overload in Pediatric Hematology: the Priority of Free-Breathing Liver Study at 3.0 T Magnetic Resonance Scanner in Children with Severe Iron Overload

Abstract

The aim of the study was to compare the effectiveness and scanning features of iron detection in the liver based on 3T MR scanner data using a breath holding and free breathing sequences in children with iron overload. 108 patients aged of 3 to 17 years with secondary iron overload associated with the regular blood transfusions underwent an MRI study on a 3.0 T MR scanner using specialized sequences for obtaining relaxometric maps: 3T-mGRE and 3T-uTE. The quality of the images received by the 3T-mGRE and 3T-uTE sequences was assessed by determining the signal-to-noise ratio (SNR). The SNR of 3T-uTE was found to be 8 times higher than the SNR of 3T-mGRE. In addition, it was found that for patients with an iron overload less than 25 mg/g the 3T-mGRE and 3T-uTE sequences showed the same efficacy in iron detection in the liver (r = 0.99, p = 0.54). The concentration of iron in the liver in patients with extremely severe iron overload could be calculated only using 3T-uTE relaxometric maps due to the high approximation error of the results obtaining by 3T-mGRE maps. These data demonstrate the possibility of using the 3T-mGRE sequence to determine the concentration of iron in the liver below 25 mg/g. However, with extremely severe iron overload, it is better to use the 3T-uTE sequence.