a needle assembly 10 compromising an infusion needle 11 that includes a needle cannula 13 made of a superelastic material such as nitinol . the needle cannula is cold - worked or heat annealed to produce a preformed bend 16 that can be straightened within passageway 21 of a coaxial outer cannula 12 for introduction into the body of a patient . upon deployment from the outer cannula , the needle cannula substantially returns to the preformed configuration for the introduction or extraction of materials at areas lateral to the entry path of the needle assembly . the needle assembly can compromise a plurality of needle cannulae than can be variably arranged or configured for attaining a desired infusion pattern .