A syringe comprising: a barrel (20) that includes a fluid chamber (18), a proximal end, a distal end defining a ceiling (50) oriented towards said proximal end, said ceiling (50) including an opening (54) ) through it, and an elongated tip (16) extending from said distal end that includes a passage (24) therethrough in fluid communication with said chamber (18) and said opening (54)； and a plunger (38) slidably disposed within said barrel (20), said plunger (38) including a piston head (52) that is oriented towards said roof (50)； characterized by a first protuberance (56) and a second protuberance (58) disposed on said roof (50), said first protuberance (56) being adapted to form a channel (61) between said plunger head (52) and said roof ( 50) when said plunger (38) is extended distally, and said second protuberance (58) being adapted to form a second channel (62) between said plunger head (52) and said roof (50), said channels being adapted first and second (61, 62) to isolate fluid from said passage (24).Una jeringa que comprende: un barril (20) que incluye una cámara de fluido (18), un extremo proximal, un extremo distal que define un techo (50) orientado hacia dicho extremo proximal, incluyendo dicho techo (50) una abertura (54) a través del mismo, y una punta alargada (16) que se extiende desde dicho extremo distal que incluye un pasaje (24) a través de la misma en comunicación fluida con dicha cámara (18) y dicha abertura (54)； y un émbolo (38) dispuesto de forma deslizante en el interior de dicho barril (20), Incluyendo dicho émbolo (38) un cabezal del émbolo (52) que está orientado hacia dicho techo (50)； caracterizada por una primera protuberancia (56) y una segunda protuberancia (58) dispuestas sobre dicho techo (50), estando adaptada dicha primera protuberancia (56) para formar un canal (61) entre dicho cabezal del émbolo (52) y dicho techo (50) cuando dicho émbolo (38) está extendido distalmente, y estando adaptada dicha segunda protuberancia (58) para
