Biomedical subjects

Per-Ola Park

Publications and source records attributed to Per-Ola Park.

4 recordsLinked to original sources

PubMed2004

Transgastric gastropexy and hiatal hernia repair for GERD under EUS control: a porcine model.

BACKGROUND: Endoluminal operations for gastroesophageal reflux currently are limited by the inability to visualize and manipulate structures outside the wall of the gut. This may be possible by using EUS. The aims of this study were the following: to define the EUS anatomy of structures outside the gut that influence reflux, to place stitches in the median arcuate ligament, to perform posterior gastropexy, and to test the feasibility of crural repair under EUS control in pigs. METHODS: In survival experiments in 22 pigs, by using a linear-array echoendoscope, the median arcuate ligament and part of the right crus were identified and punctured with a needle, which served as a carrier for a tag and thread. These were anchored into the muscle. An endoscopic sewing device was used, allowing stitches to be placed through a 2.8-mm accessory channel to any predetermined depth. New methods allowed knot tying and thread cutting through the 2.8-mm channel of the echoendoscope. RESULTS: Stitches were placed through the gastric wall into the median arcuate ligament, and one stitch was placed just beyond the wall of the lower esophageal sphincter. The stitches were tied together and locked against the gastric wall. Median lower esophageal sphincter pressure, determined manometrically, was 11 mm Hg before surgery and 21 mm Hg after stitch placement (p=0.0002). The length of the lower esophageal sphincter increased from a median of 2.8 cm before the procedure to 3.5 cm after the procedure. At the postmortem, the median force required to pull the tags out of the median arcuate ligament was 2.8 kg. CONCLUSIONS: This study demonstrates that transgastric gastroesophageal reflux surgery, by using stitching under EUS control, can significantly increase lower esophageal sphincter pressure in pigs.

Animals↗

PubMed2003

Transluminal endosurgery: single lumen access anastomotic device for flexible endoscopy.

BACKGROUND: Forming anastomoses between two hollow organs at flexible endoscopy might reduce the need for surgery for obstructing malignancy. Current methods require access to both lumens. The aim of this work was to develop methods of forming an anastomosis at flexible endoscopy, such as a gastrojejunostomy or cholecystoduodenostomy, when access to only one lumen is feasible. METHODS: A modified needle was passed through a large-channel echoendoscope from the accessible lumen into the target hollow organ. An anastomotic device was formed by using two 7F catheter segments, which were pushed over a guidewire into the target, the less accessible lumen. When released, by withdrawing the guidewire, the catheters formed a cross shape and created an anastomosis when compressed against a plate from the accessible side. OBSERVATIONS: These devices were tested in live animal experiments. With an echoendoscope in the stomach, it was repeatedly possible to place needles, threaded tags, and guidewires into the small intestine and gallbladder. In 4 to 7 days, anastomoses were formed in 16 pigs between the small intestine and the stomach, and between the gallbladder and the stomach. The initial diameter of the anastomoses ranged from 3 to 9 mm. No complication occurred. CONCLUSIONS: It is feasible to form anastomoses at flexible endoscopy when access is limited to a single side.

Anastomosis, Surgical↗

PubMed2003

Bard EndoCinch: the device, the technique, and pre-clinical studies.

There is, of course, room for improvement. More work is needed to make endoscopic suturing easier, quicker and more reliable. The single most important next goal is to construct a device, which can place multiple stitches without the need to remove the endoscope between each stitch. Devices, which can place two stitches in one go, would be a start. The development of double stitch and multiple stitch devices has been described earlier. The authors are pleased to see two alternative commercial endoscopic sewing devices appear at the last DDW which place two stitches without needing to withdraw the endoscopes--they use a double needle method.

Anastomosis, Surgical↗

PubMed2002

A through-the-scope device for suturing and tissue approximation under EUS control.

BACKGROUND: The ability to place sutures under EUS control might allow development of a new type of transluminal endosurgery. The aim of this study was to develop endoscopic methods for suturing to variable predetermined depths in the wall of the GI tract and to allow fixation of adjacent hollow organs under EUS control. METHODS: A suturing device was constructed for suturing under EUS control to any desired depth. Sutures can also be placed into hollow or solid organs within 5 cm of the endoscope tip. The device allows multiple sutures to be placed without withdrawing the endoscope. Stitching, knot-tying, and thread-cutting are achieved through a 2.8-mm accessory channel. RESULTS: Multiple (>100) sutures were placed in predetermined gut wall layers in pigs. Sutures were placed in the gallbladder (n = 7) and small intestine (n = 8) to fix the gallbladder/small intestine to the stomach and allow traction for the insertion of stents and other devices through the 2 lumens. CONCLUSION: A new method for stitching under flexible EUS control is described. This technology was used to place sutures at precise depths in the GI tract. It allowed fixation of other organs to the accessible GI tract for various purposes including delivery of stents and devices for creating anastomoses.

Animals↗