The present invention relates to an elongated device (10). The device (10) comprises an elongated body (12) having a proximal body end portion (14), a distal body end portion (16) and a longitudinal fiber lumen (18) extending from the proximal body end portion (14) to the distal body end portion (16). An optical fiber (20) extends through the fiber lumen (18) and has a distal fiber end portion (22). A socket (24) is arranged at the distal body end portion (16) of the elongated body (12), the socket (24) having a proximal socket end (28) and a distal socket end (30) and a hole (26) in axial alignment with the fiber lumen (18). The distal fiber end portion (22) is inserted in the hole (26), and the socket (24) is radio-opaque.
