The original Rotex-Nordenström instrument for sampling of cellular material was first introduced on the market by URSUS in 1975. It consists of a thin screw needle housed in a cannula with an outer diameter of either 0.8 or 1 mm and a special instrument holder.

The advantages of the screw needle technique were soon recognized and were pointed out in comparative studies by House & Thomson(2), Sinner(7) and others. The rapid acceptance of the new technique in leading radiological and cytological quarters has thereafter led to further refinement of the instrument.