Extended endoscopic mucosal resection in the esophagus and hypopharynx: a new rigid device

Stricture prevention after extended circumferential endoscopic mucosal resection by injecting autologous keratinocytes in the sheep esophagus

BACKGROUND

During the past decades, endoscopic mucosal resection (EMR) has been developed to treat early intramucosal esophageal cancers and dysplastic Barrett's esophagus. The primary drawback of this method is severe postsurgical esophageal stricture formation. The purpose of this preclinical study was to assess strategies for prevention of this major complication by injecting autologous keratinocytes in the EMR mucosal defect in the sheep model.

METHODS

Circumferential, 6-cm-long EMRs were performed in the esophagus of nine sheep. Autologous keratinocytes were harvested 2 weeks before EMR and cultured. Circumferential resection consisted of two opposite hemicircumferential mucosectomies allowing a widespread resection of 24 cm(2). Immediately after EMR, autologous keratinocytes were endoscopically injected in the mucosal defect. Animals were sacrificed after 6 months.

RESULTS

Circumferential EMRs were successfully performed in all animals. There were no intra- or postoperative complications. None of the animals developed strictures. All animals were sacrificed at 6 months as planned. Histological examinations showed fibrotic changes in 10 % (range 0-25 %) of the circumferential muscularis propria interna layer and 7.2 % (range 0-25 %) in the muscularis propria externa layer at the midportion of the EMR. No circumferential transmural fibrosis was identified.

CONCLUSIONS

Prevention of stricture formation after extensive (6-cm long) circumferential EMR of the sheep esophagus can be achieved by injecting autologous keratinocytes into the wound of the resected mucosal segment.

Anesthesiology and gastroenterology

A successful population-based colorectal cancer screening requires efficient colonoscopy practices that incorporate high throughput, safety, and patient satisfaction. There are several different modalities of nonanesthesiologist-administered sedation currently available and in development that may fulfill these requirements. Modern-day gastroenterology endoscopic procedures are complex and demand the full attention of the attending gastroenterologist and the complete cooperation of the patient. Many of these procedures will also require the anesthesiologist's knowledge, skills, abilities, and experience to ensure optimal procedure results and good patient outcomes. The goal of this review is (1) to provide a gastroenterology perspective on the use of propofol in gastroenterology endoscopic practice, and (2) to describe newer GI endoscopy procedures that gastroenterologists perform that might involve anesthesiologists.

Advanced endoscopic technologies

The use of endoscopy for diagnosing and treating ailments of the alimentary tract has evolved steadily over the past few decades, with tremendous growth and innovation in the past few years. Initially, endoscopy relied on rigid telescopes, direct visualization, and dangerously exothermic sources of illumination. The introduction of fiber optics, charge-coupled-device cameras, and increasingly efficient light sources has enabled researchers to investigate areas of the human gastrointestinal tract through flexible endoscopy not previously thought to be reachable without formal surgical exploration. The more recent advances in scope platforms, devices, and techniques have allowed researchers to push the envelope of endoscopic diagnostics and therapeutics to greater heights. Specific new platforms include ColonoSight and mother-daughter endoscopes such as the ShapeLock TransPort and the SpyGlass direct visualization system. Specific devices include the EndoCinch suturing system, the full-thickness Plicator procedure, Esophyx, the Stretta system, and the HALO(360) system. Specific new techniques include small-caliber endoscopy, endoscopic mucosal and submucosal resection, and natural orifice translumenal endoscopic surgery (NOTES). This article describes the most relevant recent advances in endoscopic innovation with regard to platform design, devices, and techniques anticipated to serve as the foundation for further research and design for developing generations of endoscopic technologies to come.