As for this invention, as for the needle hub it can provide the expedient which the hollow cavity of the said needle hub it possesses the transparent territory for observation of the medulla liquid which flows in regard to the spinal cord cannula which possesses the needle hub, the light ray it is refracted or reflects, or inside or the said transparent territory the transparent territory of the needle hub.< Selective figure >Figure 8本発明は、針ハブを有する脊髄カニューレに関し、針ハブは該針ハブの中空キャビティを流れる髄液の観察用の透明領域を有し、光線を屈折又は反射させる手段が針ハブの透明領域の内部又は該透明領域に設けられる。【選択図】図8