Surgery – Miscellaneous
Reexamination Certificate
2000-03-13
2002-01-15
Lacyk, John P. (Department: 3736)
Surgery
Miscellaneous
C600S114000
Reexamination Certificate
active
06338345
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates generally to the field of esophageal prosthetics. More specifically, a prosthesis delivery device is disclosed for submucosal insertion of a prosthetic bulking device.
BACKGROUND OF THE INVENTION
Gastroesophageal reflux is a physical condition in which stomach acids reflux, or flow back from the stomach into the esophagus. Frequent reflux episodes (two or more times per week), may result in a more severe problem known as gastroesophageal reflux disease (GERD). Gastroesophageal reflux disease is the most common form of dyspepsia, being present in approximately 40% of adults in the United States on an intermittent basis and some 10% on a daily basis.
Dyspepsia, or heartburn, is defined as a burning sensation or discomfort behind the breastbone or sternum and is the most common symptom of GERD. Other symptoms of GERD include dysphasia, odynophagia, hemorrhage, water brash, and pulmonary manifestations such as asthma, coughing or intermittent wheezing due to acid aspiration. Dyspepsia may also mimic the symptoms of a myocardial infarction or severe angina pectoris. Many factors are believed to contribute to the onset of GERD including transient lower esophageal sphincter relaxations, decreased LES resting tone, delayed stomach emptying, and an ineffective esophageal clearance. Many in the field agree, however, that the primary cause of GERD is the lack of competency of the lower esophageal sphincter.
The lower esophageal sphincter, or valve, is comprised of smooth muscle located at the gastroesophageal (GE) junction and functions to allow food and liquid to pass into the stomach but prevent regurgitation of stomach contents. At rest, the LES maintains a high-pressure zone between 10 and 30 mm Hg above intragastric pressure. Upon deglutition, the LES relaxes before the esophagus contracts, allowing food to pass through into the stomach. After food passes into the stomach, the LES contracts to prevent the stomach contents and acids from regurgitating into the esophagus. The mechanism of LES opening and closing is influenced by innervation via the vagus nerve and hormonal control of gastrin and possibly other gastrointestinal hormones.
The severity of GERD varies from patient to patient and in extreme cases complications including esophageal erosion, esophageal ulcers, and esophageal stricture are observed. Esophageal stricture is a serious condition which results from prolonged exposure of the esophageal mucosa to acid reflux. The most common clinical manifestation of stricture is dysphasia. Unlike dysphasia from non-strictured esophageal reflux, dysphasia caused by stricture is progressive in that the size of a bolus which can pass into the stomach progressively becomes smaller. In addition to esophageal erosion and ulceration, prolonged exposure of the esophageal mucosa to stomach acid can lead to a condition known as Barrett's Esophagus. Barrett's Esophagus is an esophageal disorder that is characterized by the replacement of normal squamous epithelium with abnormal columner epithelium. This change in tissue structure is clinically important not only as an indication of severe reflux, but the appearance of columner epithelium in the esophagus is indicative of cancer.
Current methods to treat gastroesophageal reflux disease consist of lifestyle changes such as weight loss, avoidance of certain foods that exacerbate the symptoms of GERD and avoidance of excessive bending. Elevation of the head of the bed helps prevent nocturnal reflux. While these avoidance strategies may be helpful, there is relatively little data supporting the efficacy of lifestyle modification alone for the treatment of GERD.
Medications for the treatment of GERD have been administered for years with little or no success. Conventional antacids, such as TUMS® and ROLAIDS®, produce short-term relief, but often have side effects including diarrhea and constipation. H
2
receptor antagonists, such as Cimetidine and Ranitidine, are relatively more effective in controlling GERD symptoms but these symptomatic therapies fail to treat the underlying cause of the disease. More powerful secretory inhibitors, such as the proton pump inhibitors Omeprazole and Lansoprazole are more effective than the H
2
antagonists but these drugs are expensive and, in the long term, produce negative side effects.
Surgery has become an attractive alternative for the treatment of GERD when lifestyle modification and medications fail to treat this debilitating condition. There are numerous reflux operations available which perhaps reflect the inadequacy of any one procedure to totally control the problem. The most commonly performed operation, Nissen Fundoplication, has been effective, but is often complicated by stricture formation or gas bloat syndrome. A laparoscopic Nissen procedure has also been developed, adding another dimension of difficulty, and long-term results remain questionable. In addition, a percutaneous laparoscopic technique has been developed. (See, for example, U.S. Pat. No. 5,006,106 to Angelchik). Minimally invasive techniques, such as transesophageal implantation of a prosthetic valve have also been attempted. (See, for example, U.S. Pat. No. 4,846,836 to Reich). Despite extensive attempts in the field to treat and prevent GERD, existing forms of treatment all have shortcomings.
In view of the foregoing, and notwithstanding the various efforts exemplified in the prior art, there remains a need for a minimally invasive bulking prosthesis and deployment methodology for transesophageal delivery into the vicinity of the lower esophageal sphincter.
SUMMARY OF THE INVENTION
In accordance with one aspect of the present invention, there is provided an overtube for coupling to the distal end of an endoscope to produce a submucosal prosthesis delivery device. The overtube comprises an elongate flexible tubular body, having a proximal end, a distal end and a longitudinal axis. At least one lumen extends into the tubular body, for receiving an endoscope. An opening is provided on the body, in communication with the lumen, and a limit surface is provided within the body, aligned with the opening to limit the depth to which tissue can enter the opening. Typically, the tubular body is defined by a sidewall and the opening is in the sidewall. The limit surface in one embodiment lies on a first plane which is offset from the sidewall and preferably is substantially parallel to the longitudinal axis. The limit surface is preferably provided with a plurality of apertures, to permit vacuum from the endoscope to draw tissue through the opening in the direction of the limit surface.
In accordance with another aspect of the present invention, there is provided a method of introducing a flowable media into a predetermined shape beneath a tissue layer. The method comprises the steps of identifying a first site on a tissue surface, and lifting tissue a predetermined distance away from the plane of the surface to create a low pressure zone beneath the tissue. A first volume of flowable media is injected into the low pressure zone so that the media takes on a shape which is influenced by the low pressure zone. The media is thereafter permitted to harden sufficiently to substantially retain the shape.
In one embodiment, the identifying a site on a tissue surface step comprises identifying a site on the wall of the esophagus. The site is preferably in the vicinity of the lower esophageal sphincter. The method may further comprise the steps of identifying a second site and introducing a second volume of flowable media into the second site, thereafter permitting the second volume of media to harden sufficiently to substantially retain the shape. At least one of the first and second site are preferably on the posterior wall of the esophagus.
In accordance with a further aspect of the present invention, there is provided a method of stabilizing a tissue site and introducing a prosthesis beneath the tissue. The method comprises the steps of providing an elongate flexible tubular device, hav
Johnson George M.
Tsukashima Ross
Yurek Matthew Thomas
Endonetics, Inc.
Knobbe Martens Olson & Bear LLP
Lacyk John P.
Szmal Brian
LandOfFree
Submucosal prosthesis delivery device does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Submucosal prosthesis delivery device, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Submucosal prosthesis delivery device will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2836119