| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
University Hospital Freiburg Freiburg, Germany
WEB—This is a Web exclusive article.
In their letter to the editor, the authors criticize our intrathecal application of gadobenate dimeglumine (Multihance, Bracco) and mention that gadopentetate dimeglumine (Magnevist, Schering) has been the better choice for enhanced imaging of the subarachnoid space and of CSF leakages.
We agree that the intrathecal use of gadopentetate dimeglumine has been evaluated more frequently in terms of safety and that a clinical trial on the intrathecal application of this agent has been performed [2-6]. Moreover, we are aware that gadopentetate dimeglumine is the only MR contrast agent to have been intrathecally applied to patients before our study [2, 3, 5, 6]. However, to suggest that we should have used gadopentetate dimeglumine in our study simply because it has been applied intrathecally previously, whereas gadobenate dimeglumine had previously been applied intrathecally in only one animal study [7], indicates a lack of understanding of the similarity and differences between gadolinium contrast agents. We believe that gadobenate dimeglumine provides decisive features that justify its use in the subarachnoid space. Although previous studies have reported a gradual diffusion of gadopentetate dimeglumine from the CSF into the CNS [4, 8], our studies with gadobenate dimeglumine in animals [7] did not indicate any visible penetration of intrathecal gadobenate dimeglumine into the CNS. The absence of penetration might additionally explain why we did not observe any necrotic lesions histologically, as Ray et al. [9] did using gadopentetate dimeglumine intrathecally.
Furthermore, numerous studies have shown that gadobenate dimeglumine provides higher T1 relaxivity than gadopentetate dimeglumine because of weak, transient interactions with proteins such as serum albumin [10]. In extradural CSF, as observed in our case, high concentrations of proteins can be assumed. Therefore, another motivation to use gadobenate dimeglumine was to obtain efficient enhancement of tiny structures and leakages.
In conclusion, we agree that there is a lack of broad safety studies on the subarachnoid use of gadobenate dimeglumine. However, based on our observations with intrathecal gadobenate dimeglumine and on other experiences with the high relaxivity of this agent, we consider gadobenate dimeglumine to be a valuable contrast agent for the depiction of CSF leakages and for enhanced imaging of the subarachnoid space. Furthermore, the safety profile of gadobenate dimeglumine is indistinguishable from that of gadopentetate dimeglumine [10].
Finally, we should also point out that not even gadopentetate dimeglumine is approved for intrathecal application, so intrathecal uses of gadopentetate dimeglumine contrast agent are similarly off-label and at the discretion of the investigating radiologist.
 Top References |
|---|
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
