title: Intranodal signal suppression in pelvic MR lymphography of prostate cancer patients: a quantitative comparison of ferumoxtran-10 and ferumoxytol.
abstract: OBJECTIVE
  The key to MR lymphography is suppression of T2* MR signal in normal lymph nodes, while retaining high signal in metastatic nodes. Our objective is to quantitatively compare the ability of ferumoxtran-10 and ferumoxytol to suppress the MR signal in normal pelvic lymph nodes.
  
  
  METHODS
  In 2010, a set of consecutive patients who underwent intravenous MR Lymphography (MRL) were included. Signal suppression in normal lymph nodes in T2*-weighted images due to uptake of USPIO (Ultra-Small Superparamagnetic Particles of Iron Oxide) was quantified. Signal suppression by two USPIO contrast agents, ferumoxtran-10 and ferumoxytol was compared using Wilcoxon's signed rank test.
  
  
  RESULTS
  Forty-four patients were included, of which all 44 had a ferumoxtran-10 MRL and 4 had additionally a ferumoxytol MRL. A total of 684 lymph nodes were identified in the images, of which 174 had been diagnosed as metastatic. USPIO-induced signal suppression in normal lymph nodes was significantly stronger in ferumoxtran-10 MRL than in ferumoxytol MRL (p< 0.005).
  
  
  CONCLUSIONS
  T2* signal suppression in normal pelvic lymph nodes is significantly stronger with ferumoxtran-10 than with ferumoxytol, which may affect diagnostic accuracy.
authors: Department of Radiology and Nuclear Medicine, Radboudumc , Nijmegen , The Netherlands.
authors: Oscar A
authors: OA
authors: Debats
authors: Department of Radiology and Nuclear Medicine, Radboudumc, Nijmegen, The Netherlands; Department of Radiology, Ziekenhuis Gelderse Vallei, Ede, The Netherlands.
authors: Ansje S
authors: AS
authors: Fortuin
authors: Department of Radiation Oncology, Radboudumc , Nijmegen , The Netherlands.
authors: Hanneke J M
authors: HJ
authors: Meijer
authors: Department of Radiology and Nuclear Medicine, Radboudumc , Nijmegen , The Netherlands.
authors: Thomas
authors: T
authors: Hambrock
authors: Department of Radiology and Nuclear Medicine, Radboudumc , Nijmegen , The Netherlands.
authors: Geert J S
authors: GJ
authors: Litjens
authors: Department of Radiology and Nuclear Medicine, Radboudumc , Nijmegen , The Netherlands.
authors: Jelle O
authors: JO
authors: Barentsz
authors: Department of Radiology and Nuclear Medicine, Radboudumc , Nijmegen , The Netherlands.
authors: Henkjan J
authors: HJ
authors: Huisman
keywords: Lymph node metastases; MR lymphography; Prostate cancer; USPIO contrast agents