Safety and efficacy of bariatric surgery in patients with advanced fibrosis

BACKGROUND

Bariatric surgery is performed safely in non-alcoholic fatty liver disease (NAFLD) patients with minimal fibrosis (stage 1-2). However, the safety and potential benefits of bariatric surgery for NAFLD with advanced fibrosis (stage 3-4) remain unclear. This study was designed to compare the safety and efficacy of bariatric surgery in patients with biopsy proven advanced fibrosis to those with minimal fibrosis.

METHODS

All patients who underwent bariatric surgery between 2005 and 2014 and had evidence of NAFLD with fibrosis score 3-4 (advanced fibrosis) based on the staging system defined by Kleiner et al. on intraoperative liver biopsy were included and compared with patients who had fibrosis score 1-2 (minimal fibrosis). The groups were compared for length of hospital stay after bariatric surgery and incidence of postoperative complications over a follow-up period of 1 year. An improvement in hepatic function tests before and 1 year after surgery was used as a parameter to evaluate for NAFLD improvement.

RESULTS

Ninety-nine patients with F3-4 (group 1) and 198 patients with F1-2 (group 2) were included. Mean age (51.9 vs 50.1 years) and body mass index (46.4 vs 46.5 kg m^-2) were similar in the two groups. Median serum aspartate aminotransferase (43  vs 30 U l^-1; normal 10-40 U l^-1) and alanine aminotransferase (40.5 vs 34 U l^-1; normal 10-50 U l^-1) were significantly higher in group 1 and improved 1 year after surgery. Median length of hospital stay after surgery was higher in group 1 than that in group 2 (4 days vs 3 days; P-value=0.002). The proportion of patients developing postoperative complications over 1 year was similar in both groups (36.4% vs 32.8%; P-value=0.54).

CONCLUSIONS

Advanced fibrosis does not increase the risk of developing postoperative complications in medically optimized patients undergoing bariatric surgery. Improvement in serum transaminase levels suggests a reduction in hepatic necroinflammatory activity following bariatric surgery.

Three years of operation of North America's first nutrient recovery facility

The first full-scale nutrient recovery installation in North America became operational in May 2009 at the Clean Water Service's Durham Advanced Wastewater Treatment Plant in Tigard, Oregon. Recovering ammonia and phosphorus from the dewatering side stream as struvite has a positive impact on plant operations. Significantly reducing the phosphorus recycle lowers the phosphorus loading on the plant, stabilizes biological phosphorus removal, reduces the amount of chemicals needed to remove phosphorus, reduces both the dry tonnes of biosolids generated and the phosphorus content of the biosolids, and provides revenue from the sale of the struvite. To increase struvite production and to decrease struvite potential in the digestion system, the Waste Activated Sludge Stripping To Remove Internal Phosphorus (WASSTRIP™) process was implemented full-scale in summer 2011. Results indicate a potential 60% increase in struvite production is achievable.

Clinical considerations for the management of residual diabetes following bariatric surgery

Residual diabetes following bariatric surgery is increasingly recognized despite initial weight loss. It occurs more commonly following banding and sleeve gastrectomy procedures than with gastric bypass, is associated with long duration and advanced stages of diabetes and is exacerbated by weight regain. Long-term diabetes management following various gastric restrictive surgery (i.e. lap banding) requires targeting weight loss, insulin resistance and insulin secretion defects with antidiabetic agents that have weight negative or neutral effects. In contrast, re-emergence of hyperglycaemia following gastric bypass may require targeting β-cell failure with insulin analogues. Revisional bariatric surgery is also a consideration. On the basis of our experience, we propose a clinical approach for long-term management of diabetes following various bariatric procedures in the presence and absence of weight regain that is based on recognized pathophysiological effects of these procedures on diabetes remission.

LabVIEW-based control and data acquisition system for cathodoluminescence experiments

Computer automation of cathodoluminescence (CL) experiments using equipment developed in our laboratory is described. The equipment provides various experiments for CL efficiency, CL spectra, and CL time response studies. The automation was realized utilizing the graphical programming environment LabVIEW. The developed application software with procedures for equipment control and data acquisition during various CL experiments is presented. As the measured CL data are distorted by technical limitations of the equipment, such as equipment spectral sensitivity and time response, data correction algorithms were incorporated into the procedures. Some examples of measured data corrections are presented.

Surgical approaches to the treatment of obesity: bariatric surgery

As the obesity epidemic continues to grow in the Unites States, so does the search for the ideal nonsurgical or surgical solution. Bariatric surgery continues to be the most sustainable form of weight loss available to morbidly obese patients. In addition, bariatric surgery has established an acceptable safety profile with respect to morbidity and mortality. With the number of elective bariatric cases growing in recent years, it is unsurprising that results have improved and better data are emerging regarding improvement of obesity-related comorbid conditions. Additionally, ample evidence suggests that bariatric surgery may increase longevity, particularly through reducing cardiovascular deaths. Although the specific mechanisms involved in the remission of these medical conditions remain to be fully elucidated, it has become clear that bariatric surgery has established a significant and firm role in the treatment of medical comorbidities that result directly from obesity. However, until commercial insurance carriers provide improved coverage for bariatric surgery, patient access to these treatments will remain limited.

Gut flora metabolism of phosphatidylcholine promotes cardiovascular disease

Metabolomics studies hold promise for discovery of pathways linked to disease processes. Cardiovascular disease (CVD) represents the leading cause of death and morbidity worldwide. A metabolomics approach was used to generate unbiased small molecule metabolic profiles in plasma that predict risk for CVD. Three metabolites of the dietary lipid phosphatidylcholine, namely choline, trimethylamine N-oxide (TMAO), and betaine, were identified and then shown to predict risk for CVD in an independent large clinical cohort. Dietary supplementation of mice with choline, TMAO or betaine promoted up-regulation of multiple macrophage scavenger receptors linked to atherosclerosis, and supplementation with choline or TMAO promoted atherosclerosis. Studies using germ-free mice confirmed a critical role for dietary choline and gut flora in TMAO production, augmented macrophage cholesterol accumulation and foam cell formation. Suppression of intestinal microflora in atherosclerosis-prone mice inhibited dietary choline-enhanced atherosclerosis. Genetic variations controlling expression of flavin monooxygenases (FMOs), an enzymatic source of TMAO, segregated with atherosclerosis in hyperlipidemic mice. Discovery of a relationship between gut flora-dependent metabolism of dietary phosphatidylcholine and CVD pathogenesis provides opportunities for development of both novel diagnostic tests and therapeutic approaches for atherosclerotic heart disease.

Panel report: best practices for the surgical treatment of obesity

BACKGROUND

Bariatric surgery is a rapidly growing field. Advances in surgical technologies and techniques have raised concerns about patient safety. Bariatric surgeons and programs are under increased scrutiny from regulatory agencies, insurers, and public health officials to provide high quality and safe care for bariatric patients at all phases of care.

METHODS

During the 2009 annual meeting of the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES), a panel of experts convened to provide updated information on patient safety and best practices in bariatric surgery. The following article is a summary of this panel presentation.

RESULTS AND CONCLUSIONS

Weight loss surgery is a field that is evolving and adapting to multiple external pressures. Safety concerns along with increasing public scrutiny have led to a systematic approach to defining best practices, creating standards of care, and identifying mechanisms to ensure that patients consistently receive the best and most effective care possible. In many ways, bariatric surgery and multidisciplinary bariatric surgery programs may serve as a model for other programs and surgical specialties in the near future.

[Oedema with acute pseudokeratoconus corneal aspect in a case of Kearns-Sayre syndrome]

INTRODUCTION

Mitochondrial encephalomyopathy is a set of rare diseases in which corneal involvement is exceptional.

CASE REPORT

A 34-year-old patient, a known carrier of Kearns-Sayre syndrome, was hospitalized for acute corneal decompensation, with a keratoconus-like hydrops stemming from an endothelial-Descemet membrane disruption. Under local hypotonic treatment, the favorable progression was fast with a decline in the edema and coaptation of the endothelial-Descemet membrane disruption.

CONCLUSION

The possible physiopathologic mechanisms are debated; the preferred hypothesis was a dysfunction of endothelial cell pumps. We emphasize the extremely complex medical management of these fragile patients presenting mitochondrial encephalopathy. General corticotherapy is contraindicated and beta-blockers including in eye drops must be used extremely carefully because of cardiac abnormalities such as conduction disturbance and/or arrhythmia and dilated cardiomyopathies.

Application and comparison of dynamic models to assess impact of loading variations on performance of denitrification filters

Dynamic models were developed using two software packages to evaluate performance of a denitrification filter pilot under variable flow and nitrate loading conditions. Two data periods, including one at constant rate hydraulic loading and one under diurnal flow conditions, were used to calibrate the models. Two additional test periods, one with high nitrate loadings and the second with peak hydraulic loadings and intermittent methanol usage were used to validate the models. The paper presents the results and compares the features of the two models.

Surgical approaches to the treatment of obesity: bariatric surgery

As bariatric surgery for the treatment of morbid obesity enters its sixth decade, much has been and continues to be learned from the results of several key bariatric operations, particularly the Roux-en-Y gastric bypass. Because of the obesity epidemic and development of the laparoscopic approach, bariatric procedures have increased exponentially in the past decade and are now among the more commonly performed gastrointestinal operations. Emerging data support the role of bariatric surgery as an effective treatment for improvement or remission of type 2 diabetes, hypertension, dyslipidemia, and multiple other comorbid conditions that accompany obesity. The mechanisms involved in the remission of these conditions, however, remain poorly understood and constitute an exciting area of research. This article delineates the current types of bariatric surgery, their respective outcomes, and their impact on obesity-related medical comorbidities.

New applications for endoscopy: the emerging field of endoluminal and transgastric bariatric surgery

Endoluminal and transgastric procedures are evolving concepts that combine the skills and techniques of flexible endoscopy with minimally invasive surgery. Precisely how this technology and skill set will be applied in the field of general surgery is not yet known, but the treatment of obesity with an endoluminal or transgastric procedure holds great promise. As the demand for bariatric surgery increases, efforts will be directed toward developing less morbid and less costly treatment options that can provide substantial weight loss and resolution of comorbid conditions. Natural orifice bariatric procedures may include short-term weight loss in preparation for a definitive laparoscopic procedure, revisional procedures to reduce stoma or pouch size or repair fistulas, or primary therapy that provides durable weight loss. The latter application will undoubtedly appeal to patients and referring physicians if it can be performed as an outpatient procedure with significantly less morbidity than a laparoscopic procedure. Early preclinical and clinical work has been published in this area, but many technical obstacles must be overcome before a primary endoluminal or transgastric bariatric procedure can be offered. This article reviews the endoluminal and transgastric technology currently available, the endoluminal procedures currently performed, and the future of these technologies with respect to bariatric surgery.

Potential role of hypothalamic ghrelin in the pathogenesis of human obesity

Ghrelin is a potent appetite stimulator, mainly synthesized in the stomach but also made in the brain. Paradoxically, obese subjects have lower plasma ghrelin than lean subjects and increase their weight in spite of low ghrelin levels. We hypothesize that central, and not peripheral ghrelin, is primarily responsible for overeating in humans. The aim of this study was to determine hypothalamic ghrelin levels in lean vs obese subjects. We collected anterior hypothalamus from lean and obese patients at the time of autopsy, and Western blots and semiquantitative RT-PCR for ghrelin and neuropeptide Y (NPY) were carried out. Our results showed that ghrelin expression was significantly higher in the hypothalamus of obese subjects compared to lean ones. This finding correlates with similar increases in NPY in the obese group. Ghrelin and NPY mRNA levels followed the same trend and were significantly higher in the hypothalamus in obese compared to lean subjects, suggesting a central origin for the increased protein content in the obese subjects. In conclusion, obesity in humans is associated with elevated central ghrelin. This data questions the significance of the role of peripheral ghrelin in the regulation of appetite in humans and suggests an important role for central ghrelin in the pathogenesis of obesity in humans.

DRESS syndrome associé à une pan-uvéite bilatérale : à propos d’un cas

INTRODUCTION

DRESS syndrome (drug rash or reaction with eosinophilia and systemic symptoms) is a rare but life-threatening drug hypersensitivity syndrome with a potential viral cofactor. The syndrome is characterized by rash, fever, hematological disorders (eosinophilia, lymphocytosis), and systemic symptoms (adenopathy, multiorgan involvement).

CASE REPORT

We report the first description of acute bilateral panuveitis with elevated intraocular pressure associated with anticonvulsant-induced DRESS syndrome, hypogammaglobulinemia, and HHV-6 reactivation in a 63-year-old-woman. Complete general and ophthalmological recovery was obtained 4 weeks after the end of anticonvulsant drug exposure without corticosteroid prescription, with the patient remaining free of disease after 6 months.

DISCUSSION

Our data suggest that uveitis may be one of multivisceral involvements described in drug hypersensitivity syndrome. The data also suggest that HHV-6 may play a role in the complex pathogenesis of DRESS as well as in the development of immune inflammatory disorders such as bilateral panuveitis with elevated intraocular pressure and alteration of retinal and choroidal circulation in this patient.

Laparoscopic sleeve gastrectomy as an initial weight-loss procedure for high-risk patients with morbid obesity

BACKGROUND

The surgical treatment of obesity in the high-risk, high-body-mass-index (BMI) (>60) patient remains a challenge. Major morbidity and mortality in these patients can approach 38% and 6%, respectively. In an effort to achieve more favorable outcomes, we have employed a two-stage approach to such high-risk patients. This study evaluates our initial outcomes with this technique.

METHODS

In this study, patients underwent laparoscopic sleeve gastrectomy (LSG) as a first stage during the period January 2002-February 2004. After achieving significant weight loss and reduction in co-morbidities, these patients then proceeded with the second stage, laparoscopic Roux-en-Y gastric bypass (LRYGBP).

RESULTS

During this time, 126 patients underwent LSG (53% female). The mean age was 49.5 +/- 0.9 years, and the mean BMI was 65.3 +/- 0.8 (range 45-91). Operative risk assessment determined that 42% were American Society of Anesthesiologists physical status score (ASA) III and 52% were ASA IV. The mean number of co-morbid conditions per patient was 9.3 +/- 0.3 with a median of 10 (range 3-17). There was one distant mortality and the incidence of major complications was 13%. Mean excess weight after LSG at 1 year was 46%. Thirty-six patients with a mean BMI of 49.1 +/- 1.3 (excess weight loss, EWL, 38%) had the second-stage LRYGBP. The mean number of co-morbidities in this group was 6.4 +/- 0.1 (reduced from 9). The ASA class of the majority of patients had been downstaged at the time of LRYGB. The mean time interval between the first and second stages was 12.6 +/- 0.8 months. The mean and median hospital stays were 3 +/- 1.7 and 2.5 (range 2-7) days, respectively. There were no deaths, and the incidence of major complications was 8%.

CONCLUSION

The staging concept of LSG followed by LRYGBP is a safe and effective surgical approach for high-risk patients seeking bariatric surgery.

Endoscopic balloon dilation of gastroenteric anastomotic stricture after laparoscopic gastric bypass

BACKGROUND AND STUDY AIMS

Laparoscopic gastric bypass is a recently introduced treatment option for morbid obesity, with promising initial results. Stenosis of the gastroenterostomy is a recognized complication. The efficacy and safety of endoscopic balloon dilation for the management of this type of anastomotic stenosis has not been studied.

PATIENTS AND METHODS

450 patients who underwent laparoscopic gastric bypass at our institution were followed prospectively. All patients had a 15 ml gastric pouch and either a 75 cm or 150 cm jejunal Roux limb depending on whether obesity was morbid (body mass index (BMI) < 50 kg/m 2) or super-morbid (BMI > 50 kg/m 2). Patients who developed symptoms compatible with stenosis of the gastrojejunostomy were referred for upper gastrointestinal endoscopy.

RESULTS

14 patients, 11 women and three men, underwent a total of 27 endoscopies, with 23 balloon dilations. Their average age was 46 years (range 33 - 59 years), average preoperative BMI was 47 kg/m 2, and they presented an average of 2.7 months after surgery (range 0.3 - 15.7 months). Of the 14 patients, 13 had a stricture of the gastrojejunostomy and one patient had edema. For initial dilation, a 15 mm hydrostatic balloon was used in 12 patients and an 18 mm balloon in two patients. There was response to treatment with the 15 mm balloon in seven of the 12 patients (58 %), and they required no further dilation; in one there was a response to a further 15 mm balloon dilation; in three patients a response to subsequent 18 mm balloon dilation; and one patient required 18 mm and 25 mm balloon dilations. The two patients treated with an initial 18 mm balloon dilation required no further dilations. The average length of follow-up after successful dilation was 18 months (range 7 - 30 months). There were no complications with any of the 23 dilations performed.

CONCLUSION

Stenosis of the gastroenterostomy after laparoscopic gastric bypass occurred in 3.1 % of the patients in this series. It can be successfully and safely treated with endoscopic balloon dilation with good long-term follow-up.

The learning curve for laparoscopic Roux-en-Y gastric bypass is 100 cases

BACKGROUND

The purpose of this study was to determine the effect of operative experience on perioperative outcomes for laparoscopic Roux-en-Y gastric bypass (LGB).

METHODS

Between July 1997 and September 2001, 750 patients underwent LGB for the treatment of morbid obesity at our center. We evaluated the perioperative outcomes of the first 150 consecutive patients to determine if a learning curve effect could be demonstrated. The patients were divided into three groups (1, 2, and 3) of 50 consecutive patients, and outcomes for each group were compared.

RESULTS

The patients in group 3 had a larger body mass index (BMI), were more likely to have had prior abdominal surgery, and were more likely to have secondary operations at the time of LGB. Operating time decreased from a mean of 311 min in group 11 to 237 min in group 3, and technical complications were reduced by 50% after an experience of 100 cases.

CONCLUSIONS

Operative time and technically related complications decreased with operative experience even though heavier patients and higher-risk patients were more predominant in the latter part of our experience. LGB is a technically challenging operation with a long learning curve. To minimize morbidity related to the learning curve, strategies for developing training programs must address these challenges.

Symptomatic improvement in gastroesophageal reflux disease (GERD) following laparoscopic Roux-en-Y gastric bypass

BACKGROUND

The purpose of this study was to determine the effect of laparoscopic Roux-en-Y gastric bypass (LRYGBP) on symptomatic control of gastroesophageal reflux disease (GERD).

METHODS

Morbidly obese patients (n = 435) who underwent LRYGBP for morbid obesity were assessed for changes in GERD symptoms, quality of life, and patient satisfaction after surgery.

RESULTS

A total of 238 patients (55%) had evidence of chronic GERD, and 152 patients (64%) voluntarily participated in the study. The mean body mass index (BMI) was 48 kg/m2. The mean excess weight loss was 68.8% at 12 months. There was a significant decrease in GERD-related symptoms, including heartburn (from 87% to 22%, p<0.001); water brash (from 18% to 7%, p<0.05); wheezing (from 40% to 5%, p<0.001) laryngitis (from 17% to 7%, p<0.05); and aspiration (from 14% to 2%, p<0.01) following LRYGBP. Postoperatively, the use of medication decreased significantly both for proton pump inhibitors (from 44% to 9%, p<0.001) and for the H2 blockers (from 60% to 10%, p<0.01). SF-36 physical function scores and the mental component summary scores improved after the operation (87 vs 71; p<0.05 and 83 vs 66; p<0.05, respectively). Overall patient satisfaction was 97%.

CONCLUSION

LRYGBP results in very good control of GERD in morbidly obese patients with follow-up as late as 3 years. Morbidly obese patients who require surgery for GERD may be better served by LRYGBP than fundoplication because of the additional benefit of significant weight loss.

Symptomatic improvement in gastroesophageal reflux disease (GERD) following laparoscopic Roux-en-Y gastric bypass

BACKGROUND

The purpose of this study was to determine the effect of laparoscopic Roux-en-Y gastric bypass (LRYGBP) on symptomatic control of gastroesophageal reflux disease (GERD).

METHODS

Morbidly obese patients (n = 435) who underwent LRYGBP for morbid obesity were assessed for changes in GERD symptoms, quality of life, and patient satisfaction after surgery.

RESULTS

A total of 238 patients (55%) had evidence of chronic GERD, and 152 patients (64%) voluntarily participated in the study. The mean body mass index (BMI) was 48 kg/m2. The mean excess weight loss was 68.8% at 12 months. There was a significant decrease in GERD-related symptoms, including heartburn (from 87% to 22%, p<0.001); water brash (from 18% to 7%, p<0.05); wheezing (from 40% to 5%, p<0.001) laryngitis (from 17% to 7%, p<0.05); and aspiration (from 14% to 2%, p<0.01) following LRYGBP. Postoperatively, the use of medication decreased significantly both for proton pump inhibitors (from 44% to 9%, p<0.001) and for the H2 blockers (from 60% to 10%, p<0.01). SF-36 physical function scores and the mental component summary scores improved after the operation (87 vs 71; p<0.05 and 83 vs 66; p<0.05, respectively). Overall patient satisfaction was 97%.

CONCLUSION

LRYGBP results in very good control of GERD in morbidly obese patients with follow-up as late as 3 years. Morbidly obese patients who require surgery for GERD may be better served by LRYGBP than fundoplication because of the additional benefit of significant weight loss.

Laparoscopic resection of a large periadrenal nonmalignant pheochromocytoma

This is, to our knowledge, the first case description of an extraadrenal pheochromocytoma located in the periadrenal fat. Pheochromocytoma is a tumor that originates in the chromaffin tissue. Extraadrenal pheochromocytomas have been described commonly in locations such as the organ of Zuckerkandle (29%); the bladder (12%); the sacrum, testis, rectum, and pelvic floor (2%); the upper abdomen in association with celiac, superior mesenteric, and inferior mesenteric ganglia (43%); the thorax (12%); and the neck (2%), most commonly in association with the ninth or tenth cranial nerve ganglion. Our patient was a 40-year-old woman known to have had an adrenal mass for the last 4 years. She was referred for surgery because of an increase in the size of the mass to 11 cm. Laparoscopic adrenalectomy was performed via a posterior flank approach. The pathology report was of periadrenal fat pheochromocytoma, with positive staining for synaptophysin, chromogranin, and vimentin. The patient was discharged on postoperative day 3. The unique feature in this case was the uncommon location of the extraadrenal tumor: the supraadrenal fat. The other unique finding in this case was that the pheochromocytoma was neither symptomatic nor malignant, common features of extraadrenal masses.

Surgical management of gastroesophageal reflux disease in obese patients

Obesity or morbid obesity is common among patients who are seeking surgery for refractory gastroesophageal reflux disease (GERD). Several surgical options for treating GERD in obese patients are available. Fundoplications may be effective, at least in the short-term, but have no effect on weight loss and comorbidity reduction. Silicone-adjustable gastric banding and Roux-en-Y gastric bypass have different antireflux mechanisms, but also have proven efficacy against GERD and result in significant weight loss and comorbidity reduction. Vertical banded gastroplasty is not an effective antireflux procedure, and it may induce GERD in some patients. The malabsorbtion operations have no proven efficacy against GERD. Patients with severe obesity who are seeking surgical treatment for GERD should be considered for silicone adjustable gastric banding or Roux-en-Y gastric bypass because of the added benefit of weight loss and consequent comorbidity reduction.

Treatment of periodontal pockets with a diode laser

BACKGROUND AND OBJECTIVE

The aim of this study is to examine the long-term effect of diode laser therapy on periodontal pockets with regard to its bactericidal abilities and the improvement of periodontal condition.

STUDY DESIGN/MATERIALS AND METHODS

Fifty patients were randomly subdivided into two groups (laser-group and control-group) and microbiologic samples were collected. There have been six appointments for 6 months following an exact treatment scheme. After evaluating periodontal indices (bleeding on probing, Quigley-Hein) including pocket depths and instruction of patients in oral hygiene and scaling therapy of all patients, the deepest pockets of each quadrant of the laser-group's patients were microbiologically examined. Afterwards, all teeth were treated with the diode laser. The control-group received the same treatment but instead of laser therapy were rinsed with H2O2. Each appointment also included a hygienic check-up. After 6 months the final values of the periodontal indices and further microbiologic samples were measured. The total bacterial count as well as specific bacteria, such as Actinobacillus actinomycetemcomitans, Prevotella intermedia, and Porphyromonas gingivalis, were assessed semiquantitatively.

RESULTS

The bacterial reduction with diode laser therapy was significantly better than in the control group. The index of bleeding on probing improved in 96.9% in the laser-group, whereas only 66.7% in the control group. Pocket depths could be more reduced in the laser group than in the control group.

CONCLUSION

The diode laser reveals a bactericidal effect and helps to reduce inflammation in the periodontal pockets in addition to scaling. The diode laser therapy, in combination with scaling, supports healing of the periodontal pockets through eliminating bacteria.

Improvement of light collection efficiency of lens-coupled YAG screen TV system for a high-voltage electron microscope

A new lens coupling television (TV) system using a YAG (Yttrium Aluminum Garnet: Y(3)Al(5)O(12) : Ce(3+)) single crystal screen has been developed for a high-voltage electron microscope (HVEM), and its performance is examined. The system, using a combination of YAG and lenses, is less damaged by high-energy electron irradiation and reduces the influence of X-rays on the image. YAG screens have not been used for lens-coupling systems, because the high refractive index (n = 1.84) of YAG results in a low light collection efficiency for emitted light. This disadvantage is overcome by combining a thin YAG disk screen (thickness; 100 microm) with a glass hemisphere whose refractive index is 1.81. We found that the light intensity is almost the same as that obtained with a conventional P22 powder screen and lenses system. The resolution is about 55 microm on the YAG screen, and this value is 1.3 times higher than that measured by the conventional system. Shading and distortion do not affect TV observation. Detection quantum efficiency, obtained after correction of the channel mixing effect, is about 0.1.

Minimally invasive esophagectomy for Barrett's esophagus with high-grade dysplasia

BACKGROUND

Barrett's esophagus with high-grade dysplasia (BE/HGD) is associated with invasive carcinoma in 30% to 70% of cases. Esophagectomy is the treatment of choice for patients with BE/HGD but esophagectomy can be associated with high morbidity and mortality. The aim of our study was to report our preliminary experience in applying minimally invasive surgical techniques to esophagectomy for BE/HGD.

METHODS

From August 1996 to February 1999, 12 consecutive patients underwent minimally invasive esophagectomy for biopsy-proven BE/HGD. Our consort consisted of 7 men and 5 women; average age was 64 years (range, 40-78 years). All patients underwent a complete laparoscopic or combined laparoscopic and thoracoscopic resection of the esophagus with cervical anastomosis.

RESULTS

Mean operative time was 7.8 +/- 2.1 hours, mean intensive care unit stay was 2.6 +/- 2.2 days, and mean length of hospital stay was 8.3 +/- 4.7 days. Five patients (42%) had carcinoma in situ or carcinoma identified on pathologic specimen. Analyses of all resected lymph nodes in the 12 patients were negative for metastatic disease. There were 6 major complications in 5 patients: 1 patient had a small bowel perforation requiring operative repair, 2 patients needed prolonged ventilatory support for respiratory insufficiency, and 3 patients had delayed gastric emptying requiring revision of the pyloromyotomy. The single minor complication in this series was a jejunostomy tube-site infection. There were no conversions to laparotomy or thoracotomy. All patients were alive and free of metastatic disease at a mean follow-up of 12.6 months.

CONCLUSIONS

Minimally invasive esophagectomy is a feasible and safe alternative to conventional open esophagectomy for patients with BE/HGD.

Minimally invasive approach to esophagectomy

BACKGROUND

Recent advances in laparoscopic and thoracoscopic surgery have made it possible to perform esophagectomy using minimally invasive techniques. The aim of this report was to present our preliminary experience with minimally invasive esophagectomy.

METHODS

We reviewed our experience on eight patients who underwent minimally invasive esophagectomy using either laparoscopic and/or thoracoscopic techniques from June 1996 to May 1997. Indications for esophagectomy included stage I carcinoma (5), palliative resection (1), Barrett's with high grade dysplasia (1) and end stage achalasia (1).

RESULTS

The average age was 68 years (54-82). The surgical approach to esophagectomy included laparoscopic transhiatal esophagectomy with cervical anastomosis (n = 4), thoracoscopic and laparoscopic esophagectomy with cervical anastomosis (n = 1), and laparoscopic mobilization with right mini-thoracotomy and intra-thoracic anastomosis (n = 3). Conversion to mini-laparotomy was required in two patients (25%) to complete esophageal dissection and facilitate gastric pull-up. The mean operative time was 460 minutes. The mean intensive care stay was 1.9 days (range of 0-7 days) with a mean hospital stay of 13.8 days. Minor complications included atrial fibrillation (n = 1), pleural effusion (n = 2) and persistent air leak (n = 1). Major complications included cervical anastomotic leak (n = 1), and delayed gastric emptying requiring pyloroplasty (n = 1). There was no perioperative mortality.

CONCLUSIONS

This preliminary experience suggests that minimally invasive esophagectomy is safe and feasible in centers with experience in advanced minimally invasive surgical procedures. Further studies are necessary to determine advantages over open esophagectomy.

Future directions in esophageal cancer

The incidence of esophageal cancer in the United States has been increasing in recent years. Since multimodality therapy for esophageal cancer has produced discouraging results, recent approaches have focused on molecular biological techniques, positron emission tomography, and minimally invasive surgery to improve pretreatment staging which will facilitate a more accurate assessment of new treatment. This article summarizes the results of studies investigating these approaches and outlines the strategy currently used at the University of Pittsburgh Medical Center.

Minimally invasive surgical biopsy confirms PET findings in esophageal cancer

This report describes our initial experience using positron emission tomography (PET) scanning in esophageal cancer patients. In two patients PET identified distant metastatic disease missed by conventional staging. Laparoscopic biopsy provided histological confirmation of metastases. In the third patient, locoregional lymph nodes were identified by PET and confirmed by surgical staging. In this preliminary report, PET appears to be a promising new noninvasive modality for staging patients with esophageal cancer.

Minimally invasive surgical staging is superior to endoscopic ultrasound in detecting lymph node metastases in esophageal cancer

OBJECTIVE

Endoscopic ultrasonography is frequently used to locally stage esophageal cancer, but few studies exist to validate its accuracy for lymph node metastases. Our objective was to compare endoscopic ultrasonography with video-assisted thoracoscopic and laparoscopic staging in evaluating lymph node metastases in esophageal cancer.

METHODS

Twenty-six patients with potentially resectable esophageal cancer were identified by conventional imaging. Endoscopic ultrasonography was performed followed by laparoscopic and thoracoscopic staging, and locoregional staging was compared.

RESULTS

In eight patients endoscopic ultrasonography indicated N0 disease, but laparoscopy and thoracoscopy documented N1 disease in six. In five of 26 (19%) obstruction prevented endoscopic ultrasonography; three had N1 by laparoscopy and thoracoscopy. Thirteen patients had N1 disease according to endoscopic ultrasonography, and 12 of 13 (92%) had N1 disease by laparoscopy and thoracoscopy. The sensitivity and specificity of endoscopic ultrasonography for nodal evaluation were 65% and 66%, respectively. Sensitivity decreased to 44% for lymph node metastases less than 1 cm. No instances of T4 disease were found by surgical staging when endoscopic ultrasonography indicated T3 disease. Endoscopic ultrasonography revealed no distant metastases in any patient, but in four of 26 (15%) laparoscopy identified liver metastases.

CONCLUSIONS

The accuracy of endoscopic ultrasonography in the diagnosis of lymph node metastases in esophageal cancer was 65% and only 44% for lymph node metastases less than 1 cm diameter. Laparoscopy and thoracoscopy improved the accuracy of staging lymph node metastases in esophageal cancer and had the advantage of evaluating the thoracic and abdominal cavities for metastases.

Bacterial reduction in periodontal pockets through irradiation with a diode laser: a pilot study

This study examines the application of a diode laser with a wavelength of 805 nm for periodontal treatment. While the use of the diode laser in this field has not been investigated so far, several authors have reported on the use of neodymium:yttrium-aluminum-garnet (Nd:YAG) laser for such applications. The aim of this study was to examine the immediate effect of the diode laser in reducing the bacterial concentration in periodontal pockets. Important periodontal indices (PBI, CPITN) were assessed in 50 patients to obtain initial values for a planned long-term study and to select appropriate periodontal pockets for this study. The periodontal pockets were required to have a minimum depth of 4 mm. Only proximal pockets were included in this study. The patients were subdivided into two groups. After microbiological samples had been collected with sterile paper tips, the group selected for laser treatment was subjected to scaling. One week after scaling, the patients underwent laser treatment. One week later, a second series of microbiological samples were obtained and the patients were subjected again to scaling; this time, however, they did not undergo laser treatment after 1 week. Two weeks after scaling, another series of microbiological samples was collected. The microbiological samples were evaluated to verify bacterial elimination from the periodontal pockets. A comparison between the initial and the final bacterial counts revealed that irradiation with the diode laser facilitates considerable bacterial elimination, especially of Actinobacillus actinomycetemcomitans, from periodontal pockets.

Effect of rat (beta)-interferon on intracellular levels of hydrolases in rat embryonal fibroblasts (Wistar strain)

The effect of rat beta-interferon (IFN) on the intracellular level of thiole and acid proteases and alkaline phosphatases was investigated. When nontransformed rat embryonal fibroblasts (REF) (Wistar strain) were treated with homologous IFN, a time independent decrease of hydrolase enzyme levels was observed. IFN treatment of transformed cells lead to a time dependent decrease of thiole proteases within 90 min. The values for acid proteases remained unchanged after the short term IFN treatment.

Lymphoblastic lymphoma in adults

Fifty-one patients with lymphoblastic lymphoma (LBL) treated with one of five successive intensive chemotherapy protocols for acute lymphoblastic leukemia (ALL) since 1971 were reviewed. The patients were divided into leukemic and nonleukemic groups, and their clinical and laboratory parameters compared. The projected 5-year survival rate for all patients treated with the L10/17 protocols was 45% for both leukemic and nonleukemic LBL. The response to treatment was compared with that of 111 patients with ALL and was nearly identical. Poor prognostic factors were age beyond 30, WBC greater than 50,000/microL, failure to achieve a complete response (CR), and a late CR during induction. Leukemia at presentation, T cell surface markers, and the presence of a mediastinal mass did not adversely affect survival. The use of intensive chemotherapy protocols has proven to be a significant advance in the treatment of LBL.

The effect of intracellular proteinases on transformation of human lymphocytes

The effect of two intracellular proteinases, calf liver chymotrypsin-like neutral proteinase and human brain cathepsin H, and of two proteinase inhibitors, leupeptin and endogenous cysteine proteinases inhibitor, was studied on unstimulated and mitogen-stimulated peripheral human blood lymphocytes. Classification of blood samples into four types, on the basis of their potential for spontaneous and mitogen-stimulated transformation, helped in analyzing the results. Within some of these types, at least, there appears certain uniformity of response to proteinase action. Lymphocytes most susceptible to proteinase action were those that were insensitive to phytohemagglutinin mitogenic stimulus. The maximal effect of proteinases or their inhibitors was obtained most often when these agents were added to lymphocyte cultures 24 hours before mitogen. Both proteinases, although of quite different specificities, gave very often results of similar trend on the same lymphocyte culture. Moreover, this was followed also by the two inhibitors, which showed not only inhibitory, but also potentiating power of action on lymphocyte transformation. The regulatory nature of the action of proteinases within lymphocytes and other cells is underlined.

Chemotherapy of metastatic sweat gland carcinoma. A retrospective review

Sweat gland carcinoma (SGC) is a rare malignancy of the skin. though many patients with SGC die of disseminated metastases, little is known regarding the value of systemic chemotherapy for this disease. We reviewed the records of 20 patients with metastatic SGC who were treated with chemotherapy at Memorial Hospital between 1968 and 1983. A large variety of drugs were given. Although only a few patients were treated with any given regimen, metastatic SGC appears to be poorly responsive to a wide variety of chemotherapeutic regimens. Five major responses were observed in 30 chemotherapy trials performed in 17 patients with measurable/evaluable disease. No patient responded to single agent therapy alone. In this small group of patients, SGC appears to be a relatively chemotherapy resistant tumor. Larger, group-wide or inter-group trials are needed to prospectively evaluate the use of chemotherapy in this disease. Doxorubicin and cyclophosphamide, the two drugs used most commonly in those combinations where responses were seen, appear to be reasonable choices for initial treatment of patients with metastatic disease. Our review does not provide data to support the empiric use of chemotherapy in an adjuvant setting.

Treatment of acute lymphoblastic leukemia in adults: results of the L-10 and L-10M protocols

Two successive protocols (L-10 and L-10M) employing multidrug induction therapy with vincristine, prednisone, and doxorubicin (Adriamycin) plus an intensive consolidation phase and maintenance program have led to a significant improvement in the prognosis of adult acute lymphoblastic leukemia (ALL). The complete remission (CR) rates for the 34 patients entered on the L-10 protocol and the 38 patients entered on the L-10M protocol were 85% and 84%, respectively. The median duration of remission has not yet been reached for either the L-10 (median follow-up, 5.5 years; range, 3.5-7.5 years) or the L-10M protocol (median follow-up, 2.5 years; range, 1-3.5 years). The median survival time has not yet been reached for the L-10M protocol. Central nervous system prophylaxis with intrathecal methotrexate alone was effective in preventing central nervous system relapse. An analysis of possible prognostic factors indicated that patients less than 25 years of age had a higher CR rate than older patients (p = 0.02). Patients with an initial leukocyte count below 15,000/microL experienced longer remissions than patients with a leukocyte count above 15,000/microL (p = 0.008), and patients who achieved CR within the first month of therapy were in remission longer than those requiring a longer time to achieve CR (p = 0.04). Patients with T cell ALL did not have a poorer prognosis than other patients treated on these protocols. The L-10 and L-10M protocols were well tolerated with minimal morbidity.

Effect of homologous and heterologous interferons on proteolytic activity of normal and transformed cells

The authors investigated the effect of various types of interferons (INF) on the activity of intracellular neutral and cysteine proteinases (cathepsin B and H) in normal and transformed rat embryonic fibroblasts. A substantially stronger inhibitory effect was observed with all three types of IFN on the proteolytic enzymes in transformed cells if compared to that on normal cells. Heterologous IFN reduces the activity of cysteine proteinases by 33% and neutral proteinases by 79%. Homologous IFN strongly reduced the activity of cysteine proteinases in transformed cells (59%) used in the experiments, but the inhibition of neutral proteinases remained nearly unchanged if compared with normal cells (18%).

The significance of splenomegaly in 101 adults with acute lymphoblastic leukemia (ALL) at presentation and during remission

One-hundred-one adult patients with ALL were analyzed to determine the prognostic implications of splenomegaly occurring at any time during the course of their illness. The clinical status of the spleen at presentation was not found to be of major prognostic significance. Complete response rates, remission durations, and survivals did not differ between patients with and without splenomegaly at presentation. An enlarged spleen accompanied relapse in four patients. In six additional patients, splenomegaly was present during complete remission, and splenectomies performed in five of these patients revealed no evidence of leukemia to account for the splenomegaly. Splenectomy does not appear to be detrimental, as all five patients are currently in complete remission from 20 to 63 mo after splenectomy. Evidence implicating the spleen as a source of an antibody directed against autologous leukemia cells in one patient is reviewed.

Morphological classification, response to therapy, and survival in 263 adult patients with acute nonlymphoblastic leukemia

Bone marrow smears of 263 protocol patients with acute nonlymphoblastic leukemia (ANLL) and related disorders treated between 1970 and 1978 at MSKCC were reviewed blindly by two pairs of hematomorphologists and classified according to the FAB system. It was found necessary to add one category (MO) for acute undifferentiated leukemia and to define more precise quantitative criteria for the categories M1-M6 based on bone marrow differential counts. Using this modified FAB classification, agreement between the two observer groups based on morphology alone was 69%. Cytochemical stains were essential in establishing the diagnosis in 9%, led to a change of diagnosis by one observer team in 14%, and helped to confirm the diagnosis in 32% of cases. Complete remission rates, remission duration, and survival were not significantly different among diagnostic categories. Myelodysplastic syndromes (MDS: M6, RAEB, CMML; CR rate 48%) and ANLL without differentiation (M0, M1, M5a; CR rate 50%) appeared to do less well than ANLL with partial differentiation (M2, M3, M4, M5b; CR rate 59%) on all three protocols studied. Auer rods were present in 53% of all cases with 63% in the myeloid categories (M1-M4). Auer rods were found to be the single most important prognostic parameter in this study, with a complete remission (CR) rate of 68% in the Auer-rod-positive and of 40% in the Auer-rod-negative group (p < 0.0001). Survival was significantly longer for patients exhibiting Auer rods (p < 0.0002). Median survival for the total group was 13.5 mo and median remission duration for responders was 11.5 mo in the Auer-rod-positive group compared to 6.2 mo median survival and 9.2 mo median remission duration for the Auer-rod-negative group.