Esophageal stricture in children: Fiber-optic endoscopy and dilatation under fluoroscopic control

We made a retrospective analysis of the efficacy and complication rate of 268 esophageal dilatation procedures performed under fluoroscopic control using the fiber-optic endoscope in 45 children with esophageal stricture. Antegrade and retrograde stricture dilatation was performed under general anesthetic, mainly as an outpatient procedure. Thirty-six children had an esophageal stricture following tracheoesophageal fistula and/or esophageal atresia repair, and nine children had severe corrosive stricture of the esophagus following lye ingestion. The procedure was well tolerated and effective. © 1992 Raven Press, Ltd., New York.

Therapeutic upper gastrointestinal endoscopy in children : An audit of 443 procedures and literature review

The safety, effectiveness and capabilities of therapeutic upper fibreoptic endoscopy in children undergoing therapeutic endoscopic procedures (n = 443) was studied. Therapy for gastrointestinal bleeding formed the major group (injection sclerotherapy for varices, n = 197 procedures; thermocoagulation for haemorrhagic gastritis, n = 1; and photocoaulation for Dieulafoy's disease, n = 1). Sclerotherapy was 97% effective in controlling acute bleeding and 84% effective in obliterating varices with no serious complications or deaths. Oesophageal dilatations for surgical, caustic, congenital and peptic strictures and achalasia (n = 193) were performed with no oesophageal perforations or deaths. Foreign bodies were retrieved (n = 34) with no failures or complications. Percutaneous endoscopic gastrostomy was performed (n = 11) with one failure, proceeding to an unsuccessful surgical gastrostomy. Miscellaneous procedures included endoscopic transpyloric tube placement (n = 5) and endoscopic diathermy of pyloric web (n = 1). Therapeutic fibreoptic endoscopy is therefore concluded to be safe and effective in children, replacing rigid oesophagoscopy and some traditional surgical approaches.

Dilatacao pneumatica no megaesofago avancado. Resultados do sequimento tardio

Six patients with advanced Chagas' megaesophagus with poor condition for surgical indication due to severe malnutrition and concomitant diseases were submitted to pneumatic dilatation with the aid of the endoscope. The method consists in leading the tip of the pneumatic dilatator into the cardia with the tip of the endoscope. Insufflation of the balloon must be slow and progressive with visualization of the mucosa of the cardia after insufflating of 2 pounds of air pressure. An excellent symptomatic relief was seen in the five-year follow-up but without improvement in the degree of the esophageal dilatation.

Heller's myotomy and pneumatic dilatation in the treatment of achalasia: a population-based case–control study assessing long-term quality of life

Long-term health-related quality-of-life (HRQL) outcomes have not been widely reported in the
treatment of achalasia. The aims of this study were to examine long-term disease-specific and general HRQL in
achalasia patients using a population-based case–control method, and to assess HRQL between treatment interventions.
Manometrically diagnosed achalasia cases (n = 120) were identified and matched with controls (n = 115)
using a population-based approach. Participants completed general (SF-12) and disease-specific (Achalasia Severity
Questionnaire [ASQ]) HRQL questionnaires, as appropriate, in a structured interview. Mean composite scores
for SF-12 (Mental Component Summary score [MCS-12] and Physical Component Summary score [PCS-12]) and
ASQ were compared between cases and controls, or between intervention groups, using an independent t-test.
Adjusted mean differences in HRQL scores were evaluated using a linear regression model. Achalasia cases were
treated with a Heller’s myotomy (n = 43), pneumatic dilatation (n = 44), or both modalities (n = 33). The median
time from last treatment to HRQL assessment was 5.7 years (interquartile range 2.4–11.5). Comparing achalasia
patients with controls, PCS-12 was significantly worse (40.9 vs. 44.2, P = 0.01), but MCS-12 was similar. However,
both PCS-12 (39.9 vs. 44.2, P = 0.03) and MCS-12 (46.7 vs. 53.5, P = 0.004) were significantly impaired in those
requiring dual treatment compared with controls. Overall however, there was no difference in adjusted HRQL
between patients treated with Heller’s myotomy, pneumatic dilatation or both treatment modalities. In summary,
despite treatment achalasia patients have significantly worse long-term physical HRQL compared with population
controls. No HRQL differences were observed between the treatment modalities to suggest a benefit of one
treatment over another.

Laparoscopic Heller Myotomy and Fundoplication in Patients with Chagas' Disease Achalasia and Massively Dilated Esophagus

Laparoscopic Heller myotomy and fundoplication is considered today the treatment of choice for achalasia. The optimal treatment for end-stage achalasia with esophageal dilation is still controversial. This multicenter and retrospective study aims to evaluate the outcome of laparoscopic Heller myotomy in patients with a massively dilated esophagus. Eleven patients (mean age, 56 years; 6 men) with massively dilated esophagus (esophageal diameter greater than 10 cm) underwent a laparoscopic Heller myotomy and anterior fundoplication between 2000 and 2009 at three different institutions. Preoperative workup included upper endoscopy, esophagram, and esophageal manometry in all patients. Average follow-up was 31.5 months (range, 3 to 60 months). Two patients (18%) had severe dysphagia, four patients (36%) had mild and occasional dysphagia to solid food, and five patients (45%) were asymptomatic. All patients gained or kept body weight, except for the two patients with severe dysphagia. Of the two patients with severe dysphagia, one underwent esophageal dilatation and the other a laparoscopic esophagectomy. They are both doing well. Heller myotomy relieves dysphagia in the majority of patients even when the esophagus is massively dilated.

Common variants at the MHC locus and at chromosome 16q24.1 predispose to Barrett's Esophagus

Barrett's esophagus is an increasingly common disease that is strongly associated with reflux of stomach acid and usually a hiatus hernia, and it strongly predisposes to esophageal adenocarcinoma (EAC), a tumor with a very poor prognosis. We report the first genome-wide association study on Barrett's esophagus, comprising 1,852 UK cases and 5,172 UK controls in the discovery stage and 5,986 cases and 12,825 controls in the replication stage. Variants at two loci were associated with disease risk: chromosome 6p21, rs9257809 (P combined = 4.09 × 10-9; odds ratio (OR) = 1.21, 95% confidence interval (CI) =1.13-1.28), within the major histocompatibility complex locus, and chromosome 16q24, rs9936833 (P combined = 2.74 × 10-10; OR = 1.14, 95% CI = 1.10-1.19), for which the closest protein-coding gene is FOXF1, which is implicated in esophageal development and structure. We found evidence that many common variants of small effect contribute to genetic susceptibility to Barrett's esophagus and that SNP alleles predisposing to obesity also increase risk for Barrett's esophagus. © 2012 Nature America, Inc. All rights reserved.

Barrett's Esophagus and Associated Adenocarcinoma : studies on pathogenesis, clinical staging and cost-utility of cancer treatment

Esophageal and gastroesophageal junction (GEJ) adenocarcinoma is rapidly increasing disease with a pathophysiology connected to oxidative stress. Exact pre-treatment clinical staging is essential for optimal care of this lethal malignancy. The cost-effectiviness of treatment is increasingly important. We measured oxidative metabolism in the distal and proximal esophagus by myeloperoxidase activity (MPA), glutathione content (GSH), and superoxide dismutase (SOD) in 20 patients operated on with Nissen fundoplication and 9 controls during a 4-year follow-up. Further, we assessed the oxidative damage of DNA by 8-hydroxydeoxyguanosine (8-OHdG) in esophageal samples of subjects (13 Barrett s metaplasia, 6 Barrett s esophagus with high-grade dysplasia, 18 adenocarcinoma of the distal esophagus/GEJ, and 14 normal controls). We estimated the accuracy (42 patients) and preoperative prognostic value (55 patients) of PET compared with computed tomography (CT) and endoscopic ultrasound (EUS) in patients with adenocarcinoma of the esophagus/GEJ. Finally, we clarified the specialty-related costs and the utility of either radical (30 patients) or palliative (23 patients) treatment of esophageal/GEJ carcinoma by the 15 D health-related quality-of-life (HRQoL) questionnaire and the survival rate. The cost-utility of radical treatment of esophageal/GEJ carcinoma was investigated using a decision tree analysis model comparing radical, palliative, and hypothetical new treatment. We found elevated oxidative stress ( measured by MPA) and decreased antioxidant defense (measured by GSH) after antireflux surgery. This indicates that antireflux surgery is not a perfect solution for oxidative stress of the esophageal mucosa. Elevated oxidative stress in turn may partly explain why adenocarcinoma of the distal esophagus is found even after successful fundoplication. In GERD patients, proximal esophageal mucosal anti-oxidative defense seems to be defective before and even years after successful antireflux surgery. In addition, antireflux surgery apparently does not change the level of oxidative stress in the proximal esophagus, suggesting that defective mucosal anti-oxidative capacity plays a role in development of oxidative damage to the esophageal mucosa in GERD. In the malignant transformation of Barrett s esophagus an important component appears to be oxidative stress. DNA damage may be mediated by 8-OHdG, which we found to be increased in Barrett s epithelium and in high-grade dysplasia as well as in adenocarcinoma of the esophagus/GEJ compared with controls. The entire esophagus of Barrett s patients suffers from increased oxidative stress ( measured by 8-OhdG). PET is a useful tool in the staging and prognostication of adenocarcinoma of the esophagus/GEJ detecting organ metastases better than CT, although its accuracy in staging of paratumoral and distant lymph nodes is limited. Radical surgery for esophageal/GEJ carcinoma provides the greatest benefit in terms of survival, and its cost-utility appears to be the best of currently available treatments.

Effect of Dilatation on the Elasto-Plastic Response of Bulk Metallic Glasses Under Indentation

Elasto-plastic response of bulk metallic glasses (BMGs) follows closely the response of granular materials through pressure dependent (or normal stress) yield locus and shear stress induced material dilatation. On a micro-structural level, material dilatation is responsible for stress softening and formation of localized shear band, however its influence on the macro-scale flow and deformation is largely unknown. In this work, we systematically analyze the effect of material dilatation on the gross indentation response of Zr-based BMG via finite element simulation. The strengthening/softening effect on the load-depth response and corresponding stress-strain profiles are presented in light of differences in elastic-plastic regimes under common indenters. Through comparison with existing experimental results, we draw conclusions regarding selection of suitable dilatation parameters for accurately predicting the gross response of BMGs

Inherent Shear-Dilatation Coexistence In Metallic Glass

Shear deformation can induce normal stress or hydrostatic stress in metallic glasses [ Nature Mater. 2 ( 2003) 449, Intermetallics 14 ( 2006) 1033]. We perform the bulk deformation of three-dimensional Cu46Zr54 metallic glass (MG) and Cu single crystal model systems using molecular dynamics simulation. The results indicate that hydrostatic stress can incur shear stress in MG, but not in crystal. The resultant pronounced asymmetry between tension and compression originates from this inherent shear-dilatation coexistence in MG.

Intrinsic correlation between dilatation and pressure sensitivity of plastic flow in metallic glasses

Taking shear-induced dilatation into consideration in shear transformation zone (STZ) operations, we derive a new yield criterion that reflects the pressure sensitivity in plastic flow in metallic glasses (MGs), which agrees well with experiments. Furthermore, an intrinsic theoretical correlation between the pressure sensitivity coefficient and the dilatation factor is revealed. It is found that the pressure sensitivity of plastic flow of MGs originates in the dilatation of microscale STZs.