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Dive into the research topics where Tom R. DeMeester is active.

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Featured researches published by Tom R. DeMeester.


Annals of Surgery | 1986

Nissen fundoplication for gastroesophageal reflux disease. Evaluation of primary repair in 100 consecutive patients.

Tom R. DeMeester; Luigi Bonavina; Mario Albertucci

One hundred consecutive patients had a primary Nissen fundoplication for gastroesophageal reflux disease. None of the patients had previous gastaric or esophageal surgery or evidence of esophageal stricture or motility disorder. The primary symptom was persistent heartburn in 89 patients and aspiration in 11. An abnormal pattern of esophageal acid exposure was documented in all patients with 24-hour esophageal pH monitoring. By actuarial analysis, the operation was 91% effective in the control of reflux symptoms over a 10-year period. The incidence of postoperative symptomatic gas bloat and increased flatus was lower in patients with preoperative abnormal manometric measurements of the distal esophageal sphincter (p < 0.05). Three modifications in operative technique were made during the course of the study to minimize the side effects of the operation. First, enlarging the caliber of the bougie to size the fundoplication reduced the incidence of temporary swallowing discomfort from 83 to 39% (p < 0.01). Second, shortening the length of the fundoplication decreased the incidence of persistent dysphagia from 21 to 3% (p < 0.01). Third, mobilizing the gastric fundus for construction of the fundoplication increased the incidence of complete distal esophageal sphincter relaxation on swallowing from 31 to 71% (p < 0.05). This was done to prevent the delayed esophageal acid clearance secondary to incomplete sphincter relaxation observed after operation in five of 36 studied patients. It is concluded that by proper patient selection and the incorporation of the above surgical techniques, the Nissen fundoplication can re-establish a competent cardia and provide relief of reflux symptoms with minimal side effects.


Annals of Surgery | 1976

Patterns of gastroesophageal reflux in health and disease.

Tom R. DeMeester; Lawrence F. Johnson; Guy J. Joseph; Michele S. Toscano; Andrew W. Hall; David B. Skinner

Twenty-four-hour pH monitoring of the distal esophagus quantitates gastroesophageal reflux in a near physiologic setting by measuring the frequency and duration of acid exposure to the esophageal mucosa. Fifteen asymptomatic volunteers were studied with 24-hour pH and esophageal manometry. The normal cardia was more competent supine than in the upright position. Physiologic reflux was unaffected by age, rarely occurred during slumber, and was the rule after alimentation. One hundred symptomatic patients with an abnormal 24-hour pH record (2 S.D. above the mean of controls) could be divided into three patterns of pathological reflux: those who refluxed only in the upright position (9), only in the supine position (37), and in both positions (54). Upright differed from supine refluxers by excessive aerophagia causing reflux episodes by repetitive belching. Compared to controls, they had excessive post-prandial reflux, lower DES pressure, and less DES exposed to the positive pressure of the abdomen. Supine differed from upright refluxers by having a higher incidence of esophagitis and an inability to clear the esophagus of acid after a supine reflux episode. Compared to controls, they had only a lower DES pressure. Combined refluxers had a higher incidence of esophagatis than supine refluxers. Stricture (15%) was seen only in this group. They were similar to supine refluxers in their inability to clear a supine reflux episode. Compared to controls, they had a lower DES pressure and less DES exposed to the positive pressure of the abdomen. Forty of the 100 patients had an antireflux procedure (4 upright, 8 supine, 28 combined). The most severe postoperative flatus and abdominal distention was seen in the upright refluxers. It is concluded that minimal reflux is physiological. Patients with pathological reflux all have lower DES pressure. Patients with upright reflux have less of their DES exposed to the positive pressure environment of the abdomen. Patients with supine reflux have an inability to clear the esophagus of reflux acid and are prone to develop esophagitis. Patients with both upright and supine reflux have the most severe disease and are at risk in developing strictures. In patients with only upright reflux, aerophagia and delayed gastric emptying may be an important etiological factor.


Digestive Diseases and Sciences | 1993

Esophageal Eosinophilia with Dysphagia A Distinct Clinicopathologic Syndrome

Stephen E. A. Attwood; Thomas C. Smyrk; Tom R. DeMeester; James B. Jones

Small numbers of intraepithelial esophageal eosinophils (IEE) may be seen in 50% of patients with gastroesophageal reflux disease and occasionally in normal volunteers. High concentrations of IEE are rarely seen in either setting. During a two-year period we idetified 12 adult patients with very dense eosinophil infiltrates in esophageal biopsies (defined as >20 IEE/high-power field). Dysphagia was the presenting complaint in each, but no evidence of anatomical obstruction could be found. Endoscopic esophagitis was absent, but biopsy showed marked squamous hyperplasia and many IEE. Eleven patients had normal esophageal acid exposure on 24-hr pH monitoring. Esophageal manometry showed a nonspecific motility disturbance in 10 patients. For comparison, 90 patients with excess esophageal acid exposure on 24-hr pH monitoring were studied. Thirteen (14%) had motility disturbance, and 21 (23%) had dysphagia. Esophageal biopsies were devoid of IEE in 47 patients; none of the 43 with IEE had infiltrates as dense as those seen in the 12 study patients. The presence of high concentrations of IEE in esophageal biopsies from patients with dysphagia, normal endoscopy, and normal 24-hr esophageal pH monitoring represents a distinctive clinicopathologic syndrome not previously described.


Annals of Surgery | 1994

Laparoscopic Nissen fundoplication is an effective treatment for gastroesophageal reflux disease.

Ronald A. Hinder; Charles J. Filipi; Gerold J. Wetscher; Patricia Neary; Tom R. DeMeester; Galen Perdikis

ObjectveThe open Nissen fundoplication is effective therapy for gastroesophageal reflux disease. In this study, the outcomes in 198 patients treated with the laparoscopic Nissen fundoplication was evaluated for up to 32 months after surgery to ascertain whether similar positive results could be obtained. Summary Background DataTo ensure surgical success, patients were required to have mechanically defective sphincters on manometry and increased esophageal acid exposure on 24-hour pH monitoring. The patients either had severe complications of gastroesophageal reflux disease or had failed medical therapy. These requirements have been found to be necessary to ensure a successful surgical outcome. MethodsThe disease was complicated by ulceration (46), stricture (25) and Barretts esophagus (33). Patients underwent standard Nissen fundoplications identical in every detail to open procedures except that the procedures were carried out by the laparoscopic route. ResultsPerioperative complications included gastric or esophageal perforation (3), pneumothorax (2), bleeding (2), breakdown of crural repair (2) and periesophageal abscess (1). The only mortality occurred from a duodenal perforation. Six patients required conversion to the open procedure. The median hospital stay was 3 days. One hundred patients were observed for follow-up for 6 to 32 months (median 12 months), with outcomes similar to the open Nissen fundoplication. Further surgery was required for two patients who had recurrent gastroesophageal reflux and one who developed an esophageal stricture. Ninety-seven percent are satisfied with their decision to have the operation. ConclusionsThe laparoscopic Nissen fundoplication can be carried out safely and effectively with similar positive results to the open procedure and with all of the advantages of the minimally invasive approach.


Journal of The American College of Surgeons | 2000

Laparoscopic repair of large type III hiatal hernia: objective followup reveals high recurrence rate

Majid Hashemi; Jeffrey H. Peters; Tom R. DeMeester; James E. Huprich; Marcus L. Quek; Jeffrey A. Hagen; Peter F. Crookes; Jörg Theisen; Steven R. DeMeester; Lelan F. Sillin; Cedric G. Bremner

BACKGROUND Recent studies based on symptomatic outcomes analyses have shown that laparoscopic repair of large type III hiatal hernias is safe, successful, and equivalent to open repair. These outcomes analyses were based on a relatively short followup period and lack objective confirmation that the hernia has not recurred. The aim of this study was to compare the outcomes of laparoscopic and open repair of large type III hiatal hernia using both symptomatic evaluation and barium study to assess the integrity of the repair. STUDY DESIGN Fifty-four patients underwent repair of a large type III hiatal hernia between 1985 and 1998. The surgical approach was laparotomy in 13, thoracotomy in 14, and laparoscopy in 27. An antireflux procedure was included in all patients. Symptomatic outcomes were assessed using a structured questionnaire at a median of 24 months and was complete in 51 of 54 patients (94%). A single radiologist, without knowledge of the operative procedure, assessed the integrity of the repair using video esophagram. Videos were performed at a median of 27 months (35 months open and 17 laparoscopic) and were completed in 41 of 54 patients (75%). RESULTS Symptomatic outcomes were similar in both groups with excellent or good outcomes in 76% of the patients after laparoscopic repair and 88% after an open repair. Reherniation was present in 12 patients and was asymptomatic in 7. A recurrent hernia was present in 12 of the 41 patients (29%) who returned for a followup video esophagram. Forty-two percent (9 of 21) of the laparoscopic group had a recurrent hernia compared with 15% (3 of 20) of the open group (p < 0.001 log-rank value on recurrence-free followup). CONCLUSIONS Laparoscopic repair of type III hiatal hernias is associated with a disturbingly high (42%) prevalence of recurrent hernia. More than half such recurrences have few, if any, symptoms.


The Journal of Thoracic and Cardiovascular Surgery | 1994

Outcome of adenocarcinoma arising in Barrett's esophagus in endoscopically surveyed and nonsurveyed patients

Jeffrey H. Peters; Geoffrey W.B. Clark; Adrian P. Ireland; Para Chandrasoma; Thomas C. Smyrk; Tom R. DeMeester

The value of endoscopic surveillance of Barretts esophagus and the appropriate management of high-grade dysplasia remain unclear. Seventeen patients who were referred from endoscopic surveillance programs for management of high-grade dysplasia or adenocarcinoma developing in Barretts esophagus were compared with 35 patients who had a newly recognized Barretts adenocarcinoma, who had not been in a surveillance program. The referral diagnosis in the surveyed group was adenocarcinoma in six and high-grade dysplasia in 11. After repeat endoscopy with aggressive biopsy, two additional patients with adenocarcinoma were identified. Of the nine patients who underwent esophagectomy for high-grade dysplasia, five had invasive adenocarcinoma in the esophagectomy specimen, which had been missed before the operation, despite the fact that the median number of biopsy specimens obtained per 2 cm of Barretts mucosa was 7.8 (range 1.5 to 15.0). Overall, 13 patients in the surveyed group had adenocarcinoma, 12 staged early and one staged intermediate by the WNM classification. Surveyed patients were operated on at an earlier stage than the nonsurveyed patients (10 early, 14 intermediate, and 11 late stage tumors; chi 2 = 15.6, p < 0.01). Despite the presence of adenocarcinoma in 13 of the 17 surveyed patients, their survival was significantly better than that of the nonsurveyed group (chi 2 = 5.8, p < 0.05). Patients referred from surveillance programs for Barretts esophagus have a better outcome and earlier stage tumors than nonsurveyed patients. Inasmuch as multiple biopsy procedures do not exclude the presence of adenocarcinoma, continued surveillance of high-grade dysplasia is dangerous and potentially destructive to surveillance efforts.


American Journal of Surgery | 1988

The lower esophageal sphincter in health and disease.

Giovanni Zaninotto; Tom R. DeMeester; Werner Schwizer; Kari Erik Johansson; Shih Chuan Cheng

The ability of the lower esophageal sphincter to protect the esophageal mucosa from exposure to gastric juice depends on its resting pressure, length exposed to abdominal pressure, and overall length. Mechanical incompetency of the sphincter can occur when one or more of these components fail. The purpose of this study was to measure manometrically the normal percentile values for these components, and to identify the point differentiating a mechanically competent from an incompetent sphincter. The results show that a mechanically incompetent sphincter can be identified by a sphincter pressure below the 2.5 percentile, an abdominal length below the fifth percentile, and an overall length below the 2.5 percentile of normal values. Sixty percent of the patients with documented increased esophageal exposure to acid gastric juice had a mechanically incompetent sphincter.


Annals of Surgery | 2008

The Number of Lymph Nodes Removed Predicts Survival in Esophageal Cancer: An International Study on the Impact of Extent of Surgical Resection

Christian G. Peyre; Jeffrey A. Hagen; Steven R. DeMeester; Nasser K. Altorki; Ermanno Ancona; S Michael Griffin; Arnulf H. Hölscher; Toni Lerut; Simon Law; Thomas W. Rice; Alberto Ruol; J. Jan B. van Lanschot; John Wong; Tom R. DeMeester

Objective:Surveillance, Epidemiology and End Results (SEER) data indicate that number of lymph nodes removed impacts survival in gastric cancer. Our aim was to study this relationship in esophageal cancer. Methods:The study population included 2303 esophageal cancer patients (1381 adenocarcinoma, 922 squamous) from 9 international centers that had R0 esophagectomy prior to 2002 and were followed at regular intervals for 5 years or until death. Patients treated with neoadjuvant or adjuvant therapy were excluded. Results:Operations consisted of esophagectomy with (1700) and without (603) thoracotomy. Median number of nodes removed was 17 (IQR10-29). There were 508 patients with stage I, 853 stage II, and 942 stage III. Five-year survival was 40%. Cox regression analysis showed that the number of lymph nodes removed was an independent predictor of survival (P < 0.0001). The optimal threshold predicted by Cox regression for this survival benefit was removal of a minimum of 23 nodes. Other independent predictors of survival were the number of involved nodes, depth of invasion, presence of nodal metastasis, and cell type. Conclusions:The number of lymph nodes removed is an independent predictor of survival after esophagectomy for cancer. To maximize this survival benefit a minimum of 23 regional lymph nodes must be removed.


Annals of Surgery | 1995

Mixed reflux of gastric and duodenal juices is more harmful to the esophagus than gastric juice alone. The need for surgical therapy re-emphasized.

Werner K. H. Kauer; Jeffrey H. Peters; Tom R. DeMeester; Adrian P. Ireland; Cedric G. Bremner; Jeffrey A. Hagen

Objective The authors goal was to determine the role of duodenal components in the development of complications of gastroesophageal reflux disease. Summary and Background Data There is a disturbing increase in the prevalence of complications, specifically the development of Barretts esophagus among patients with gastroesophageal reflux disease. Earlier studies using pH monitoring and aspiration techniques have shown that increased esophageal exposure to fluid with a pH above 7, that is, of potential duodenal origin, may be an important factor in this phenomenon. Methods The presence of duodenal content in the esophagus was studied in 53 patients with gastroesophageal reflux disease confirmed by 24‐hour pH monitoring. A portable spectrophotometer (Bilitec 2000, Synectics, Inc.) with a fiberoptic probe was used to measure intraluminal bilirubin as a marker for duodenal juice in the esophagus. Normal values for bilirubin monitoring were established for 25 healthy subjects. In a subgroup of 22 patients, a custom‐made program was used to correlate simultaneous pH and bilirubin absorbance readings. Results Fifty‐eight percent of patients were found to have increased esophageal exposure to gastric and duodenal juices. The degree of mucosal damage increased when duodenal juice was refluxed into the esophagus, in that patients with Barretts metaplasia (n = 27) had a significantly higher prevalence of abnormal esophageal bilirubin exposure than did those with erosive esophagitis (n = 10) or with no injury (n = 16). They also had a greater esophageal bilirubin exposure compared with patients without Barretts changes, with or without esophagitis. The correlation of pH and bilirubin monitoring showed that the majority (87%) of esophageal bilirubin exposure occurred when the pH of the esophagus was between 4 and 7. Conclusions Reflux of duodenal juice in gastroesophageal reflux disease is more common than pH studies alone would suggest. The combined reflux of gastric and duodenal juices causes severe esophageal mucosal damage. The vast majority of duodenal reflux occurs at a pH range of 4 to 7, at which bile acids, the major component of duodenal juice, are capable of damaging the esophageal mucosa.


Annals of Surgery | 2001

Curative Resection for Esophageal Adenocarcinoma Analysis Of 100 En Bloc Esophagectomies

Jeffrey A. Hagen; Steven R. DeMeester; Jeffrey H. Peters; Para Chandrasoma; Tom R. DeMeester

ObjectiveTo document what can be accomplished with surgical resection done according to the classical principles of surgical oncology. MethodsOne hundred consecutive patients underwent en bloc esophagectomy for esophageal adenocarcinoma. No patient received pre- or postoperative chemotherapy or radiation therapy. Tumor depth and number and location of involved lymph nodes were recorded. A lymph node ratio was calculated by dividing the number of involved nodes by the total number removed. Follow-up was complete in all patients. The median follow-up of surviving patients was 40 months, with 23 patients surviving 5 years or more. ResultsThe overall actuarial survival rate at 5 years was 52%. Survival rates by American Joint Commission on Cancer (AJCC) stage were stage 1 (n = 26), 94%; stage 2a (n = 11), 65%; stage 2b (n = 13), 65%; stage 3 (n = 32), 23%; and stage 4 (n = 18), 27%. Sixteen tumors were confined to the mucosa, 16 to the submucosa, and 13 to the muscularis propria, and 55 were transmural. Tumor depth and the number and ratio of involved nodes were predictors of survival. Metastases to celiac (n = 16) or other distant node sites (n = 26) were not associated with decreased survival. Local recurrence was seen in only one patient. Latent nodal recurrence outside the surgical field occurred in 9 patients and systemic metastases in 31. Tumor depth, the number of involved nodes, and the lymph node ratio were important predictors of systemic recurrence. The surgical death rate was 6%. ConclusionLong-term survival from adenocarcinoma of the esophagus can be achieved in more than half the patients who undergo en bloc resection. One third of patients with lymph node involvement survived 5 years. Local control is excellent after en bloc resection. The extent of disease associated with tumors confined to the mucosa and submucosa provides justification for more limited and less morbid resections.

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Jeffrey A. Hagen

University of Southern California

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Steven R. DeMeester

University of Southern California

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Cedric G. Bremner

University of Southern California

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John C. Lipham

University of Southern California

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Peter F. Crookes

University of Southern California

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Parakrama Chandrasoma

University of Southern California

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Shahin Ayazi

University of Southern California

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Farzaneh Banki

University of Texas Health Science Center at Houston

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