Catheter for percutaneous gastrostomy

Claim 2

A catheter of plastic material for percutaneous gastrostomy inserted through an abdominal wall into a gastric lumen and located there with respect to a stomach wall by a retaining means to be positioned in the gastric lumen, wherein the catheter comprises a portion serving as remaining means which is stretched out at least approximately rectinlinearly during the introduction of the catheter through the abdominal wall into the gastric lumen, and after insertion in the gastric lumen said portion of the catheter assumes a spirally curved configuration including a bearing portion facing toward the interior of said gastric lumen such that any tensile stress to which the catheter is subjected, is distributed uniformly over a great part of the curved portion, and a free end of the catheter is directed toward the interior of said gastric lumen, wherein said portion of the catheter assumes a spirallly curved configuration such that a plane of the spiral is perpendicular to the direction of the bearing portion and a section of the catheter which passes the stomach wall.

Claim 3

A catheter of plastic material for percutaneous gastrostomy inserted through an abdominal wall into a gastric lumen and located there with respect to a stomach wall by a retaining means to be positioned in the gastric lumen, wherein the catheter comprises a portion serving as retaining means which is stretched out at least approximately rectinlinearly during introduction of the catheter through the abdominal wall into the gastric lumen and assumes a curved shape upon insertion in the gastric lumen, and after insertion in the gastric lumen, said portion of the catheter assumes a spirally curved configuration including a bearing portion facing toward the interior of said gastric lumen such that any tensile stress to which the catheter is subjected, is distributed uniformly over a great part of the curved portion, and a free end of the catheter is directed toward the interior of said gastric lumen, wherein the wall of the catheter contains at least one laid-in member made of a memory alloy which is embedded in the wall and leaves said portion of the catheter stretched at one given temperature, where it will adopt the spirally curved configuration at another given temperature.

Claim 4

A catheter of plastic material for percutaneous gastrostomy inserted through an abdominal wall into a gastric lumen and located there with respect to a stomach wall by a retaining means to be positioned in the gastric lumen, wherein the catheter comprises a portion serving as retaining means which is stretched out at least approximately rectinlinearly during introduction of the catheter through the abdominal wall into the gastric lumen and assumes a curved shape upon insertion in the gastric lumen, and after insertion in the gastric lumen, said portion of the catheter assumes a spirally curved configuration including a bearing portion facing toward the interior of said gastric lumen such that any tensile stress to which the catheter is subjected, is distributed uniformly over a great part of the curved portion, and a free end of the catheter is directed toward the interior of said gastric lumen, wherein the wall of the catheter contains at least one laid-in member made of a memory alloy which is embedded in the wall and leaves said portion of the catheter stretched at one given temperature, where it will adopt the spirally curved configuration at another given temperature.

Claim 5

The catheter as in claim 2, wherein two laid-in members of memory alloy are embedded diametrically opposite each other in the catheter wall.