Neuropediatrics 2013; 44 - PS14_1222
DOI: 10.1055/s-0033-1337790

Longitudinal Evaluation of Brain Iron Depositions in a Patient With Confirmed c19orf12 Mutation Using R2* Relaxometry and Quantitative Susceptibility Mapping

U Löbel 1, A Meyer-Osores 2, J Sedlacik 1, F Schweser 3, R Grosse 2, A Deistung 3, JR Reichenbach 3, A Schulz 2, M Hartig 4, A Kohlschütter 2
  • 1Diagnostische und Interventionelle Neuroradiologie, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
  • 2Klinik und Poliklinik für Kinder-und Jugendmedizin, Universitätsklinikum Hamburg-Eppendorf, Hamburg, Germany
  • 3Medical Physics Group, Insitut für Diagnostische und Interventionelle Radiologie I, Jena, Germany
  • 4Institut für Humangenetik, München, Germany

Introduction: During recent years, the number of diseases classified as neurodegeneration with brain iron accumulation (NBIA) has steadily increased. Although the underlying mechanisms linking the iron deposition to the neurodegeneration and clinical symptoms remain unclear, recent therapeutic trials have aimed at a reduction of the cerebral iron content. We report a novel method, quantitative susceptibility mapping (QSM), which was used to monitor treatment effects of deferiprone in a patient with mitochondrial membrane protein-associated neurodegeneration (MPAN).

Case report: A 13-year-old girl presented with a 6-year history of progressive visual loss due to optic nerve atrophy and recent development of mild cognitive decline and gait abnormalities. In addition to bilateral atrophy of the optic nerve, the initial MRI showed low T2 signal of globus pallidus (GP) and substantia nigra (SN), suggestive of NBIA. MPAN was diagnosed by the molecular genetic finding of a compound heterozygous mutation of the mitochondrial c19orf12 gene. The patient was treated with deferiprone (10 mg/KG p.o.). MRI was performed prior to initiation of therapy and after 8 months using R2* relaxometry and QSM. Measurements for GP before and during treatment were as follows: R2*, 85 versus 88/s, susceptibility 0.35 versus 0.37 ppm and an iron content of 27 versus 30 mg/100 g. For SN: R2* 66 versus 59/s and susceptibility 0.42 versus 0.43 ppm and an estimated iron content of 33 versus 33 mg/100 g. R2* values were much higher compared with healthy adults (age 20 – 75y, R2*= 33/s and 36/s, estimated iron content based on QSM, 20 and 15 mg/100 g for GP and SN, respectively).

Conclusion: R2* relaxometry and QSM allow the quantification of the brain iron content. The susceptibility measured by QSM is directly proportional to the concentration of paramagnetic iron. Both methods are valuable in the diagnosis and follow-up of NBIA patients treated with iron-chelating agents.