US Patent 7422138 Elliptical intraluminal surgical stapler for anastomosis

A surgical stapler includes a head in which a plurality of staples are stored. The head includes a facing surface. The stapler also includes an anvil having an anvil surface shaped and dimensioned for forming the staples upon actuation of the surgical stapler, the anvil including a facing surface opposed to the facing surface of the head for mating engagement therewith. The facing surface of the head is obliquely oriented relative to a longitudinal axis of the head creating an elliptical staple line when the head is brought into contact with anvil during actuation of the surgical stapler.