Eugene A. Trowers

Endoscopic hemorrhoidal ligation: preliminary clinical experience

BACKGROUND Endoscopic hemorrhoidal ligation may provide an alternative to surgical treatment of internal hemorrhoids. This study assessed the safety and efficacy of endoscopic elastic band ligation for bleeding internal hemorrhoids. METHODS Endoscopic hemorrhoid ligation was performed in 20 adult patients who had chronic rectal bleeding attributed to internal hemorrhoids. Elastic band ligation was accomplished using a ligating device attached to the end of a video endoscope. Repeat endoscopy was done 3 weeks after the initial procedure. RESULTS Seventy band ligations were performed during 23 separate sessions. Post-therapy endoscopy showed reduction of hemorrhoidal size by at least one grade in 19 of 20 patients (95%). Bleeding resolved in 19 of 20 patients (95%) in 5.4 months (mean) of follow-up; 18 of 20 (90%) required only one banding session. No major complications (perforation, secondary bleeding, deep ulceration) occurred in this small group. CONCLUSIONS Preliminary data indicates that endoscopic hemorrhoidal ligation is a safe and effective technique for treating internal hemorrhoids. It holds promise as an important technique for successfully treating and possibly eradicating symptomatic internal hemorrhoids.

Changes in esophageal wall layers during motility: measurements with a new miniature ultrasound suction device

We have developed a miniaturized ultrasound device that attaches to the gastrointestinal mucosa by suction and produces high-resolution (+/- 0.1 mm) images of the layers of the intestinal wall. The esophageal wall layers in a single sheep were measured during 20 occlusive contractions observed with simultaneous endoscopy, which revealed thickening of the inner circular muscle layer from 1.2 +/- 0.2 mm to 2.2 +/- 0.4 mm (p < 0.01), and during 20 dilations demonstrating thinning of the full thickness of the esophageal wall from 3.6 +/- 0.3 mm to 2.9 +/- 0.3 mm (p < 0.01). Safety experiments performed in two canine stomachs demonstrated no erosions or ulceration at any level of suction. Our investigations indicate that the M-mode suction ultrasound device can safely assess changes occurring in the layers of the esophageal wall during contractions and dilations and should be evaluated for the study of human intestinal motility.

Simultaneous M-mode echoesophagram and manometry in the sheep esophagus

We report the simultaneous measurement of esophageal wall layer thickness and intraluminal pressure in the sheep esophagus using a miniature suction device incorporating a high-frequency ultrasound transducer and a manometry system. Transnasal placement of the device into the distal esophagus of a conscious sheep allowed observation of 133 swallowing events during three trials, each lasting from 45 to 60 minutes. In a fourth trial, 11 sequential dry and 23 sequential wet swallows were compared. Maximum manometric pressure, esophageal wall layer thickness, and duration of contraction were measured. All swallowing events produced simultaneous increases in intraluminal pressure and esophageal wall thickness. Mean maximal pressures were lower for dry swallows (18 +/- 2.1 mm Hg) than wet swallows (22 +/- 3.0 mm Hg) (p < .01). Thickness of the inner (circular) muscle layer increased above baseline by 124% for dry swallows and 161% for wet swallows (p < .01). We conclude that thickening of the esophageal inner (circular) muscle layer may be important in the generation of intraluminal esophageal pressure in the sheep esophagus.

Gallbladder wall thickening: An in vitro sonographic study with histologic correlation

RATIONALE AND OBJECTIVES We compared histologic sections with in vitro sonographic images for 40 resected gallbladder specimens to correlate the histopathologic processes with the sonographic appearance of the gallbladder wall. METHODS In vitro sonographic images and histologic specimens were obtained by use of a specimen container with a micropositioner. An 8.5-MHz transducer and a scalpel were attached to the micropositioner to obtain the sonographic image and the histologic section. The sonographic images were analyzed for wall thickness and the number and echo texture of the visualized layers and then were correlated with the histologic sections. Each histologic specimen was interpreted as being normal or showing mild, chronic, acute, or gangrenous cholecystitis. RESULTS One to four sonographic layers were observed in the gallbladder wall specimens. The number of wall layers was fairly evenly distributed among the different types of gallbladder wall inflammation. One to three sonographic layers were observed for most of the different types. In nearly all instances, the findings were attributable to either similar pathologic processes in two or more histologic layers or different pathologic processes in a single histologic layer. The gallbladder wall measured less than or equal to 3 mm in 89% of gallbladders with normal or mild inflammation, greater than 3-6 mm in 71% of cases of chronic cholecystitis, greater than 3 mm in 83% of cases of acute cholecystitis, and greater than 6 mm in 50% of cases of gangrenous cholecystitis. CONCLUSIONS The sonographic layers in the inflamed gallbladder wall are determined by the pathologic changes present rather than by the normal histologic boundaries. However, because of the overlap of pathologic changes, we cannot predict the type of gallbladder wall pathology on the basis of the sonographic appearance. We found a trend toward gallbladder wall thickening for severely inflamed gallbladder walls.

Primary Pancreatic Lymphoma Associated With Short Bowel Syndrome: Review of Carcinogenesis of Gastrointestinal Malignancies

We describe a case of stage IE diffuse small cleaved B-cell lymphoma involving primarily the head of pancreas in a patient with chronic malabsorption as a result of short bowel syndrome. The association of chronic malabsorption with lymphoma and other cancer is reviewed. The possible role of dietary fat as an etiologic link to this association is speculated.

Clinical Study of Ursodeoxycholic Acid in Barrett's Esophagus Patients

Prior research strongly implicates gastric acid and bile acids, two major components of the gastroesophageal refluxate, in the development of Barretts esophagus and its pathogenesis. Ursodeoxycholic acid (UDCA), a hydrophilic bile acid, has been shown to protect esophageal cells against oxidative stress induced by cytotoxic bile acids. We conducted a pilot clinical study to evaluate the clinical activity of UDCA in patients with Barretts esophagus. Twenty-nine patients with Barretts esophagus received UDCA treatment at a daily dose of 13 to 15 mg/kg/day for 6 months. The clinical activity of UDCA was assessed by evaluating changes in gastric bile acid composition and markers of oxidative DNA damage (8-hydroxydeoxyguanosine), cell proliferation (Ki67), and apoptosis (cleaved caspase-3) in Barretts esophagus epithelium. The bile acid concentrations in gastric fluid were measured by liquid chromatography/mass spectrometry. At baseline, UDCA (sum of unchanged and glycine/taurine conjugates) accounted for 18.2% of total gastric bile acids. After UDCA intervention, UDCA increased significantly to account for 93.4% of total gastric bile acids (P < 0.0001). The expression of markers of oxidative DNA damage, cell proliferation, and apoptosis was assessed in the Barretts esophagus biopsies by IHC. The selected tissue biomarkers were unchanged after 6 months of UDCA intervention. We conclude that high-dose UDCA supplementation for 6 months resulted in favorable changes in gastric bile acid composition but did not modulate selected markers of oxidative DNA damage, cell proliferation, and apoptosis in the Barretts esophagus epithelium. Cancer Prev Res; 9(7); 528–33. ©2016 AACR. See related article by Brian J. Reid, p. 512

Role of stents and laser therapy in biliary strictures

The most frequent primary cancers causing malignant obstructive jaundice were pancreatic cancer (57%), hilar biliary cancer (19% including metastatic disease), nonhilar biliary cancer (14%) and papillary cancer (10%). Endoscopic stenting has widely replaced palliative surgery for malignant biliary obstruction because of its lower risk and cost. Self-expandable metal stents are the preferred mode of palliation for hilar malignancies. Plastic stents have a major role in benign biliary strictures. Major complications and disadvantages associated with metallic stents include high cost, cholangitis. malposition, migration, unextractability, and breakage of the stents, pancreatitis and stent dysfunction. Dysfunction due to tumor ingrowth can be relieved by thermal methods (argon plasma coagulator therapy). We present a concise review of the efficacy of metallic stents for palliation of malignant strictures.

Elevated lactate level predicts intensive care unit admissions, endoscopies and transfusions in patients with acute gastrointestinal bleeding

Background and aims Initial clinical management decision in patients with acute gastrointestinal bleeding (GIB) is often based on identifying high- and low-risk patients. Little is known about the role of lactate measurement in the triage of patients with acute GIB. We intended to assess if lactate on presentation is predictive of need for intervention in patients with acute GIB. Patients and methods We performed a single-center, retrospective, cross-sectional study including patients ≥18 years old presenting to emergency with acute GIB between January 2014 and December 2014. Intensive care unit (ICU) admission, inpatient endoscopy (upper endoscopy and/or colonoscopy), and packed red blood cell (PRBC) transfusion were assessed as outcomes. Analyses included univariate and multivariate logistic regression analyses. Results Of 1,237 patients with acute GIB, 468 (37.8%) had venous lactate on presentation. Of these patients, 165 (35.2%) had an elevated lactate level (>2.0 mmol/L). Patients with an elevated lactate level were more likely to be admitted to ICU than patients with a normal lactate level (adjusted odds ratio [AOR] 2.96, 95% confidence interval [CI] 1.74–5.01; p<0.001). Patients with an elevated lactate level were more likely to receive PRBC transfusion (AOR 3.65, 95% CI 1.76–7.55; p<0.001) and endoscopy (AOR 1.64, 95% CI 1.02–2.65; p=0.04) than patients with a normal lactate level. Conclusion Elevated lactate level predicts the need for ICU admissions, transfusions, and endoscopies in patients with acute GIB. Lactate measurement may be a useful adjunctive test in the triage of patients with acute GIB.

Form and Function: The Physiological Implications of the Anatomy of the Gastrointestinal System

This chapter helps the reader to delineate the functions which the digestive system has been designed to address and define the key anatomic components of the gastrointestinal (GI) wall. This knowledge is used to understand how the GI smooth muscle functions as a syncytium and to describe its electrical activity. Related to this the reader learns to delineate the general features of neural control of the GI wall by the autonomic nervous system (extrinsic component: parasympathetic and sympathetic nervous systems, intrinsic component: enteric nervous system) and to describe the roles of the myenteric and submucosal plexuses. Further consideration is given to outlining the regulatory functions of GI peptides, hormones, neurocrines, and paracrines. With regard to relationship to the circulatory system, the anatomy of the GI blood supply is outlined and the splanchnic circulation is described. Finally with specific consideration of digestion the requirements for nutrient exchange are discussed and the basics of absorption including describing the (a) role of the liver in the absorption of water-soluble nutrients, (b) role of the intestinal lymphatics in the absorption of fat-based nutrients, (c) effect of gut activity and metabolic factors on GI blood flow, and (d) effect of the nervous system on GI blood flow.

Physiology of the Liver, Gallbladder and Pancreas: “Getting By” with Some Help from Your Friends

This chapter focuses on the roles of the liver, gallbladder, and pancreas in gastrointestinal physiology. The liver contains three main cell types that are described. The formation and function of bile acids and salts are explored further considering how they aid in the formation of micelles that facilitate the absorption of lipids. Recirculation of bile salts from the ileum is considered by discussion of enterohepatic circulation. Finally the roles of both acinar and ductal cells in pancreatic exocrine secretion are explained.