Reporting & Statistical Analysis The reporting of this trial will conform to the reporting guidelines outlined in the CONSORT statement of 2010. The statistical analysis will be by intention-to-treat. The occurrence of the primary outcome, number and frequency of correct ventriculostomy, will be compared between the two randomization groups. The secondary outcome analyses will compare the above described variables between randomization groups. Subgroup analyses will be performed to evaluate whether other parameters such as age, ventricle size, diagnosis or experience of the surgeon may influence the results. Data are presented as mean and standard deviation or as median with 25/75 percentiles. Stata version 11.2 (College Station, Texas) will be used for all analyses.