It was at that time (middle Ages) that several Arab physicians such as Avicenne, Rhazes, and Avenzhoer described many types of nervous system diseases and the techniques to treat them. But it was mainly Abulkassim Al Zahraoui (Abulkassis) who was the pioneer of neurosurgery as he devoted one volume of his treatise (made up of 30 volumes) to neurosurgery, a precise description of many aspects of neurosurgical pathology, its treatment, instruments and neurosurgical techniques. The classic traditions were conserved in the Islamic world for eight centuries. Therefore it is no wonder, that probably the first evidence of a surgical treatment of hydrocephalus may be this citation of Abulkassim, who worked in the Arabian Cordoba in the 10th century: "....We must open the ... skull, make the liquid flow out, than close the wound

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