Ultrasmall superparamagnetic iron oxide-enhanced magnetic resonance imaging in experimental autoimmune encephalitis

✍ Scribed by Martin Bendszus; Guido Stoll

• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 38 KB
• Volume: 21
• Category: Article
• ISSN: 1053-1807
• DOI: 10.1002/jmri.20299

✦ Synopsis

Dear Sir,

We read with great interest the recent study by Rausch et al (1) demonstrating a reduced accumulation of iron-labeled macrophages in experimental autoimmune encephalitis after treatment with a sphingosin agonist. They stated that iron accumulation in the CNS of subjects that received treatment was compared with that in a randomized control group that received a vehicle, and that the control group revealed a more extensive uptake of iron particles. When we took a closer look at the images provided, we found surprising similarities between the MR images of the vehicle group in this study and a naı ¨ve control group in another study published by this group in 2003 (2). In particular, Figure 2 of both articles resembles closely, as well as the MR image of Fig. 4 (Ref. 1) is very similar to figure 2a (lower left in Ref. 2). Neither paper refers to the other.

It may well be that this similarity is accidental, or a mix-up of the MR images has occurred. If, however, the recent study in the JMRI in 2004 used an old, historical control group we would like to challenge this paper due to methodological reasons: since immunization with guinea pig spinal cord might lead to variable disease severity between two sets of experiments it is essential to have a direct comparison with a vehicle treated EAE control group for assessment of a novel therapy. Based on the similarity of the pic-tures it appears that a historical control group has been used which is not appropriate and, moreover, was not indicated in the paper.

With kind regards,