The nozzle (4) has a tubular portion defining a passage channel which extends between a proximal opening at an outside of an intraocular cavity and a distal opening within the cavity. A blocking unit blocks the nozzle in a position in which the nozzle crosses sclera and/or conjunctiva, where blocking opposes movement of the nozzle. The blocking unit is in the form of an annular groove formed outside of the nozzle such that walls of the sclera and/or conjunctiva are sandwiched between shoulders once the nozzle inserted through walls of the sclera and/or conjunctiva.
