Dear Editor,

I have read with interest the recent paper by Mansoor et al. [1]. The authors performed a retrospective study on accuracy and complication rates of external ventricular drain placement (EVD) with twist drill and bolt system versus standard trephine and tunnelation.

The reported number of tunnelated EVD-placements in Table 2 mismatches the given percentage in the same table. As the Text of the paper does not reflect the exact number of misplacements, there is no possibility to reproduce the published percentage of misplacements of tunnelated EVDs. A correction of the content of Table 2 is therefore essential.

With kind regards,

Dr. med. univ. Ghassan Kerry.

Department of Neurosurgery.

Paracelsus Medical University, Nuremberg, Germany.