Abstract: A device whose main part is a catheter or probe which is advantageously made up by an echogenic tube on its whole length, and which is proportionally transparent. The structure is made up by a material chosen from among the group comprising amorphous thermoplastic polymer matrices incorporating a braid, strand or strip with a non metal echogenic material which is biocompatible and chosen from among filled or un-filled semi-crystalline thermoplastic polymers.