A description is given of a support device (10) comprising a flexible cannula (1), substantially cylindrical and hollow, which extends from a curled proximal end (3) to a distal end (2) provided with an expandable balloon (5), for use as support of a conical device (100) to be constructed during a surgical operation from a patch in resorbable fabric (1), for use in the replacement and reconstruction of excised tissues of a renal pelvis and/or of a ureteropelvic junction so as to facilitate the tissue reconstruction thereof in the original form.
