Dear Editor,

I read with interest the review of structural magnetic resonance imaging by Symms et al. [1] and we appreciate that our work on the diagnosis of diffuse axonal injury by means of T2*-weighted imaging [2] has been mentioned in this review.

However, I should like to point out that the results of our study have been quoted inaccurately. As Symms et al. [1] correctly report, we found a correlation between the T2* lesion load and the period of loss of consciousness, as was meassured by the Glascow Coma Scale score. [3] We did not find a correlation between number and site of traumatic microbleeds and an overall long-term clinical outcome parameter such as the extended Glasgow Outcome Scale. [4]

Just like the finding of a correlation would have been, the latter result is interesting to note too, because it questions the relevance of diffuse axonal injury for long-term clinical outcome. However, as we have emphasized, the clinical and prognostic implications of these findings will have to be examined further by correlation with detailed neuropsychologic testing. This complementary study is currently in progress.

References

(1). Symms M, Jäger HR, Schmierer K, Yousry TA. A review of structural magnetic resonance neuroimaging. J Neurol Neurosurg Psychiatry 2004; 75: 1235-1244.

(2). Scheid R, Preul C, Gruber O, Wiggins C, von Cramon DY. Diffuse axonal injury associated with chronic traumatic brain injury: Evidence from T2*- weighted gradient-echo imaging at 3 T. AJNR Am J Neuroradiol 2003; 24: 1049-1056.

(3). Teasdale G, Jennett B. Assessment of coma and impaired consciousness. A practical scale. Lancet 1974; 2: 81-84.

(4). Jennet B, Snoeck J, Bond MR, Brooks N. Disability after severe head injury: observations on the use of Glasgow outcome scale. J Neurol Neurosurg Psychiatry 1981; 44: 285-293.