Abstract: A medical device for delivering material through tissue into a defined area of a patient may comprise: a material delivery element through which the material may flow out of a delivery end; the delivery end having an opening that can be inserted through a surface of the tissue; and a sealing system proximal to the delivery end that can extend away from the material delivery element along the surface of the tissue and apply pressure to the tissue after the material delivery element has been inserted through the surface of the tissue. A physical barrier may be provided on the material delivery device to reduce back flow loss of delivered material.