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Robert A Ganz

Publications and source records attributed to Robert A Ganz.

9 recordsLinked to original sources
PubMed2006

Accurate localization of tissue layers in the esophagus by using a double-lumen injection catheter: implications for the Enteryx procedure.

BACKGROUND: Enteryx (Boston Scientific Corp, Natick, Mass) is an injectable polymer used for the treatment of GERD. Current use of Enteryx requires fluoroscopy for accurate placement into the deep esophageal wall (ie, the deep submucosa or muscularis propria). In this study, we assessed the use of a new double-lumen, double-needle injection catheter for accurate placement of Enteryx into the deep esophageal wall, without fluoroscopy, in a porcine model. METHODS: All procedures were performed by using a new injection catheter (GZ Medical, LLC, Minnetonka, Minn), which allows for tissue depth assessment via the flow of gas through one lumen and the injection of a therapeutic substance (Enteryx) via a second lumen. Endoscopy was performed on 5 consecutive pigs by using the new catheter alone, without fluoroscopy, and attempting deep injections. Four injections of Enteryx were made at the gastroesophageal junction, 10 cm above the junction, and 15 cm above the junction. A total of 60 sites (12 per animal) were injected. The animals were sacrificed and each esophagus was harvested. The mediastinal cavity was searched for extravasated Enteryx material, and the esophagus was examined grossly for Enteryx adherent to the outside wall. Injection sites then were classified morphologically as superficial (mucosa or submucosa), deep (muscularis propria or deep submucosa contiguous to muscularis), subadventitial (between muscle and adventitia), or transmural. Only deep injections were considered adequate. RESULTS: No extravasated Enteryx was found in the mediastinum in 60 injected sites. One area of transmural injection had Enteryx adherent to the outside esophageal wall (1.7%). Fifty-one injected sites (85%) were adequate deep injections, 4 injections (6.7%) were subadventitial, 1 injection (1.7%) was superficial, and 3 injections (5%) could not be assessed. There were no complications observed in any animal. CONCLUSIONS: By using a new injection device without fluoroscopy, Enteryx can be deposited consistently into the deep esophageal wall with a high degree of accuracy, avoiding mediastinal extravasation. Additional clinical trials are necessary to determine the relative accuracy and role of the new technique compared to standard radiographically guided placement.

Animals↗
PubMed2005

Helicobacter pylori in patients can be killed by visible light.

BACKGROUND: Helicobacter pylori colonizes the mucus layer of the human stomach and may cause peptic ulcer and adenocarcinoma. Novel antimicrobial approaches are sought due to the occurrence of antibiotic resistance and consequent treatment failure. We report here that H. pylori is susceptible to inactivation by blue light. STUDY DESIGN/MATERIALS AND METHODS: A controlled, prospective, blinded, trial of endoscopically delivered blue light to eradicate H. pylori in regions of the gastric antrum, in 10 patients between the ages of 21 and 80 who tested positive for H. pylori. Light (405 nm) (40 J/cm2) was delivered to a 1-cm diameter spot in the gastric antrum via optical fiber passed through the endoscope and weighed biopsies were taken from treated and control spots and colonies quantitatively cultured. RESULTS: Blue light killed 5 logs of bacteria in vitro. The mean reduction in H. pylori colonies per gram tissue between treated and control spots was 91% (7.4+/-4.8 x 10(6) vs. 8.1+/-1.9 x 10(7), two-tailed P < 0.0001). Some patients had reductions approaching 99%. No differences were observed on histological examination of light-treated and control gastric tissue. CONCLUSION: Blue light phototherapy may represent a novel approach to eradication of H. pylori, particularly, in patients who have failed standard antibiotic treatment.

Adult↗
PubMed2005

The interview.

Explore the source record for details and available documents.

Career Choice↗
PubMed2005

Enteryx implantation for GERD: expanded multicenter trial results and interim postapproval follow-up to 24 months.

BACKGROUND: Enteryx implantation in the esophagus is an alternative therapy for patients with proton pump inhibitor (PPI) dependent GERD. Although this treatment resulted in highly significant improvement at 6 and 12 months, longer follow-up is needed to more fully assess the durability of these positive effects. METHODS: An open-label, international clinical trial was conducted in 144 PPI-dependent patients with GERD with follow-up at 6 and 12 months. In addition, the durability and the safety of the treatment were assessed for 24 months in 64 patients enrolled in a postapproval study. The primary study outcome measure was usage of PPI. Secondary outcomes in the multicenter trial were GERD health-related quality of life (GERD-HRQL) symptom score and esophageal acid exposure. RESULTS: At 12 months, PPI use was reduced > or =50% in 84%: 95% confidence interval (CI) [76%, 90%] and was eliminated in 73%: 95% CI[64%, 81%] of evaluable patients (intent-to-treat analysis 78%: 95% CI[70%, 84%] and 68%: 95% CI[60%, 76%], respectively). A GERD-HRQL < or =11 was attained in 78%: 95% CI[69%, 85%] of evaluable patients. Esophageal acid exposure (total time pH <4) was reduced by 31%: 95% CI[17%, 43%]. At 24 months, a > or =50% or greater reduction in PPI use was achieved in 72%: 95% CI[59%, 82%] and PPI use was eliminated in 67%: 95% CI[54%, 78%] of patients. CONCLUSIONS: This investigation provides evidence for sustained effectiveness and safety of implantation of Enteryx in the esophagus in PPI-dependent patients with GERD.

Belgium↗
PubMed2005

Helicobacter pylori accumulates photoactive porphyrins and is killed by visible light.

Helicobacter pylori colonizes the mucus layer of the human stomach and duodenum, causes chronic gastritis, gastric ulcer, and is a risk factor for gastric adenocarcinoma. There is a 20% failure rate in antibiotic therapy, which is increasingly due to antibiotic resistance and necessitates the search for alternative antimicrobial methods. We have discovered that H. pylori when cultured in liquid medium, accumulates significant quantities of coproporphyrin and protoporphyrin IX, both in the cells and secreted into the medium. These photoactive porphyrins lead to cell death (up to 5 logs) by photodynamic action upon illumination with low doses of visible light, with blue/violet light being most efficient. The degree of killing increases with the age of the culture and is greater than that found with Propionibacterium acnes (another bacterium known to be photosensitive due to porphyrin accumulation). Both virulent and drug-resistant strains are killed. The data suggest that phototherapy might be used to treat H. pylori infection in the human stomach.

Adult↗
PubMed2004

Complete ablation of esophageal epithelium with a balloon-based bipolar electrode: a phased evaluation in the porcine and in the human esophagus.

BACKGROUND: The aim of this study was to evaluate the endoscopic and the histologic effects of a balloon-based bipolar radiofrequency electrode for ablation of porcine and human esophageal epithelium. METHODS: All procedures were performed with a balloon-based, bipolar radiofrequency system that creates a circumferential, thin-layer epithelial ablation zone within the esophagus. In Phase I, multiple ablations were created in 10 farm swine, followed by acute euthanasia and histologic assessment for completeness of epithelial removal and ablation depth. In Phase II, multiple ablations were created in 19 farm swine, with varying power and energy density, followed by endoscopy at 2 and 4 weeks to assess stricture formation. In Phase III, 3 ablations were created in 12 farm swine, with varying energy density (5, 8, 10, 12, 15, or 20 J/cm 2 ) at 350 W. Animals were euthanized at 48 hours. Histologic examination determined the percentage of epithelium removed and the ablation depth. In Phase IV, 3 patients underwent esophageal epithelial ablation before esophagectomy, creating separate lesions proximal to the tumor. Completeness of epithelial ablation and ablation depth was quantified histologically. RESULTS: In Phase I, complete removal of esophageal epithelium was achieved at energy density settings of 9.7 to 29.5 J/cm 2 . In Phase II, 9.7 and 10.6 J/cm 2 produced no stricture, whereas more than 20 J/cm 2 produced a stricture in every case. In Phase III, 8-20 J/cm 2 resulted in 100% epithelial ablation. Five and 8 J/cm 2 spared the muscularis mucosae, whereas 10 J/cm 2 caused injury to the muscularis mucosae but preserved the submucosa. In Phase IV, histologic examination demonstrated full-thickness epithelial removal in areas of electrode contact. Ablation extended only to the muscularis mucosae, without injury to submucosa. CONCLUSIONS: In the porcine and the human esophagus, circumferential, full-thickness ablation of epithelium without direct injury to the submucosa is possible and was well tolerated. In all cases, depth of ablation was linearly related to energy density of treatment.

Adenocarcinoma↗
PubMed2002

Regulation and certification issues.

Regulatory and certification issues for endoscopy are complex, detailed, and broad. The different sources of the myriad regulations often have conflicting agendas, and the venues that seek to regulate endoscopic practice often overlap and seem redundant. Nonetheless, in spite of, or perhaps as a result of stringent regulation, endoscopy in the United States in thriving and continues to grow each year. Moreover, the penalties for not following the various regulations can be severe, and may result in criminal and civil sanctions. Any physician starting or already participating in a freestanding endoscopy center is well served by becoming familiar with the intent and generalities of each regulatory situation, and seeking appropriate legal and consulting counsel for specifics.

Certificate of Need↗