New insights into the pathophysiology of achalasia and implications for future treatment.

Idiopathic achalasia is an archetype esophageal motor disorder, causing significant impairment of eating ability and reducing quality of life. The pathophysiological underpinnings of this condition are loss of esophageal peristalsis and insufficient relaxation of the lower esophageal sphincter (LES). The clinical manifestations include dysphagia for both solids and liquids, regurgitation of esophageal contents, retrosternal chest pain, cough, aspiration, weight loss and heartburn. Even though idiopathic achalasia was first described more than 300 years ago, researchers are only now beginning to unravel its complex etiology and molecular pathology. The most recent findings indicate an autoimmune component, as suggested by the presence of circulating anti-myenteric plexus autoantibodies, and a genetic predisposition, as suggested by observed correlations with other well-defined genetic syndromes such as Allgrove syndrome and multiple endocrine neoplasia type 2 B syndrome. Viral agents (herpes, varicella zoster) have also been proposed as causative and promoting factors. Unfortunately, the therapeutic approaches available today do not resolve the causes of the disease, and only target the consequential changes to the involved tissues, such as destruction of the LES, rather than restoring or modifying the underlying pathology. New therapies should aim to stop the disease at early stages, thereby preventing the consequential changes from developing and inhibiting permanent damage. This review focuses on the known characteristics of idiopathic achalasia that will help promote understanding its pathogenesis and improve therapeutic management to positively impact the patient's quality of life.

Single-incision laparoscopic cholecystectomy: is it a plausible alternative to the traditional four-port laparoscopic approach?

The current standard-of-care for treatment of cholecystectomy is the four port laparoscopic approach. The development of single incision/laparoendoscopic single site surgery (SILC/LESS) has now led to the development of new techniques for removal of the gallbladder. The use of SILC/LESS is now currently being evaluated as the next step in treatment of cholecystectomy. This review is an attempt to consolidate the current knowledge and analyze the feasibility of world-wide implementation of SILC/LESS.

Learning curve in a Western training center of the circumferential en bloc esophageal endoscopic submucosal dissection in an in vivo animal model.

Aim. Evaluate the feasibility to overcome the learning curve in a western training center of the en bloc circumferential esophageal (ECE-) ESD in an in vivo animal model. Methods. ECE-ESD was performed on ten canine models under general anesthesia on artificial lesions at the esophagus marked with coagulation points. After the ESD each canine model was euthanized and surgical resection of the esophagus and stomach was carried out according to "the Principles of Humane Experimental Technique, Russel and Burch." The specimen was fixed with needles on cork submerged in formalin with the esophagus and stomach then delivered to the pathology department to be analyzed. Results. ECE-ESD was completed without complications in the last 3/10 animal models. Mean duration for the procedures was 192 ± 35 minutes (range 140-235 minutes). All the procedures were done at the animal lab surgery room with cardio pulmonary monitoring and artificial ventilation by staff surgery members and a staff member of the Gastroenterology department trained during 1999-2001 at the Fujigaoka hospital of the Showa U. in Yokohama, Japan, length (range 15-18 mm) and 51 ± 6.99 width (range 40-60 mm). Conclusion. ECE-ESD training is feasible in canine models for postgraduate endoscopy fellows.

Endoscopic submucosal dissection in dogs in a World Gastroenterology Organisation training center.

AIM: To evaluate if canine models are appropriate for teaching endoscopy fellows the techniques of endoscopic submucosal dissection (ESD). METHODS: ESD was performed in 10 canine models under general anesthesia, on artificial lesions of the esophagus or stomach marked with coagulation points. After ESD, each canine model was euthanized and surgical resection of the esophagus or stomach was carried out according to "The Principles of Humane Experimental Technique, Russel and Burch". The ESD specimens were fixed with needles on cork submerged in a formol solution with the esophagus or stomach, and delivered to the pathology department to be analyzed. RESULTS: ESD was completed without complications using the Hook-knife in five esophageal areas, with a procedural duration of 124 +/- 19 min, a length of 27.4 +/- 2.6 mm and a width of 21 +/- 2.4 mm. ESD was also completed without complications using the IT-knife2 in five gastric areas, with a procedural duration of 92.6 +/- 19 min, a length of 32 +/- 2.5 mm and a width of 18 +/- 3.7 mm. CONCLUSION: ESD is feasible in the normal esophagus and stomach of canine models, which are appropriate for teaching this technique.

Enucleation of esophageal leiomyoma by video-assisted thoracic surgery.

Thoracoscopic enucleation of benign distal esophageal leiomyoma is a minimally-invasive procedure that is comprised of four basic steps: (1) port placement and exposure, (2) dissection, (3) reconstruction, and (4) drain placement and closure. The procedure can be performed with minimal perioperative pain, excellent morbidity and mortality, and a high-degree of patient satisfaction. Some patients may experience mild dysphagia or dyspepsia in the postoperative interval, which is managed medically with proton pump inhibitors or surgically with antireflux repair.