A medical device, comprising: a delivery catheter (300, 400) comprising: a first cylindrical member that defines a first lumen, the first cylindrical member having a proximal and a distal end, the first cylindrical member dimensioned to deliver fluid from a fluid source at the proximal end through the first lumen and into a central void of a hollow structure at the distal end; a second cylindrical member that defines a second cylindrical member that defines a second lumen that is dimensioned to allow for the passage of a guidewire; and the hollow structure, initially in a pleated and folded configuration, comprising: a proximal neck detachably engaged to the first cylindrical member; a distal neck; a wall with an interior surface that defines a central void; a proximal opening, defined by the proximal neck that allows for the passage of fluid from the first lumen into the central void; and a distal opening, defined by the distal neck, that allows for the passage of the second cylindrical member through the hollow structure; wherein: the central void of the hollow structure and the first lumen of the catheter are fluidly connected, the passage of fluid from the first lumen of the catheter into the central void of the pleated and folded hollow structure results in expansion of the pleated and folded hollow structure; the hollow structure, when expanded, assumes a shape wherein the body of the expanded hollow structure is generally round or cylindrical; the distal neck of the hollow structure is detachably engaged to the second cylindrical member; the delivery catheter configured to enable the passage of metal coils or wires through the delivery catheter and into the central void of the hollow structure after expansion of the hollow structure; and the delivery catheter is configured to enable the separation of the catheter and the expanded hollow structure. a delivery catheter (300, 400) comprising: a first cylindrical member that defines a first lumen, the first cylindrical member having a proximal and a distal end, the first cylindrical member dimensioned to deliver fluid from a fluid source at the proximal end through the first lumen and into a central void of a hollow structure at the distal end; a second cylindrical member that defines a second cylindrical member that defines a second lumen that is dimensioned to allow for the passage of a guidewire; and a first cylindrical member that defines a first lumen, the first cylindrical member having a proximal and a distal end, the first cylindrical member dimensioned to deliver fluid from a fluid source at the proximal end through the first lumen and into a central void of a hollow structure at the distal end; a second cylindrical member that defines a second cylindrical member that defines a second lumen that is dimensioned to allow for the passage of a guidewire; and the hollow structure, initially in a pleated and folded configuration, comprising: a proximal neck detachably engaged to the first cylindrical member; a distal neck; a wall with an interior surface that defines a central void; a proximal opening, defined by the proximal neck that allows for the passage of fluid from the first lumen into the central void; and a distal opening, defined by the distal neck, that allows for the passage of the second cylindrical member through the hollow structure; a proximal neck detachably engaged to the first cylindrical member; a distal neck; a wall with an interior surface that defines a central void; a proximal opening, defined by the proximal neck that allows for the passage of fluid from the first lumen into the central void; and a distal opening, defined by the distal neck, that allows for the passage of the second cylindrical member through the hollow structure; wherein: the central void of the hollow structure and the first lumen of the catheter are fluidly connected, the passage of fluid from the first lumen of the catheter into the central void of the pleated and folded hollow structure results in expansion of the pleated and folded hollow structure; the hollow structure, when expanded, assumes a shape wherein the body of the expanded hollow structure is generally round or cylindrical; the distal neck of the hollow structure is detachably engaged to the second cylindrical member; the delivery catheter configured to enable the passage of metal coils or wires through the delivery catheter and into the central void of the hollow structure after expansion of the hollow structure; and the delivery catheter is configured to enable the separation of the catheter and the expanded hollow structure. the central void of the hollow structure and the first lumen of the catheter are fluidly connected, the passage of fluid from the first lumen of the catheter into the central void of the pleated and folded hollow structure results in expansion of the pleated and folded hollow structure; the hollow structure, when expanded, assumes a shape wherein the body of the expanded hollow structure is generally round or cylindrical; the distal neck of the hollow structure is detachably engaged to the second cylindrical member; the delivery catheter configured to enable the passage of metal coils or wires through the delivery catheter and into the central void of the hollow structure after expansion of the hollow structure; and the delivery catheter is configured to enable the separation of the catheter and the expanded hollow structure.