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Dive into the research topics where Nathaniel J. Soper is active.

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Featured researches published by Nathaniel J. Soper.


The Journal of Urology | 1991

Laparoscopic Nephrectomy: Initial Case Report

Ralph V. Clayman; Louis R. Kavoussi; Nathaniel J. Soper; Stephen M. Dierks; Shimon Meretyk; Michael D. Darcy; Frederick D. Roemer; Edward D. Pingleton; Paul G. Thomson; Stephenie R. Long

A tumor-bearing right kidney was completely excised from an 85-year-old woman using a laparoscopic approach. A newly devised method for intra-abdominal organ entrapment and a recently developed laparoscopic tissue morcellator made it possible to deliver the 190 gm. kidney through an 11 mm. incision.


Annals of Surgery | 2004

Proving the value of simulation in laparoscopic surgery

Gerald M. Fried; Liane S. Feldman; Melina C. Vassiliou; Shannon A. Fraser; Donna Stanbridge; Gabriela Ghitulescu; Christopher G. Andrew; R. Bruce D. Schirmer; Thomas R. Gadacz; R. Frank G. Moody; Nathaniel J. Soper; Jeffrey P. Gold; Lawrence W. Way

Objective:To assess the McGill Inanimate System for Training and Evaluation of Laparoscopic Skills (MISTELS) physical laparoscopic simulator for construct and predictive validity and for its educational utility. Summary Background Data:MISTELS is the physical simulator incorporated by the Society of American Gastrointestinal and Endoscopic Surgeons (SAGES) in their Fundamentals of Laparoscopic Surgery (FLS) program. MISTELS’ metrics have been shown to have high interrater and test-retest reliability and to correlate with skill in animal surgery. Methods:Over 200 surgeons and trainees from 5 countries were assessed using MISTELS in a series of experiments to assess the validity of the system and to evaluate whether practicing MISTELS basic skills (transferring) would result in skill acquisition transferable to complex laparoscopic tasks (suturing). Results:Face validity was confirmed through questioning 44 experienced laparoscopic surgeons using global rating scales. MISTELS scores increased progressively with increasing laparoscopic experience (n = 215, P < 0.0001), and residents followed over time improved their scores (n = 24, P < 0.0001), evidence of construct validity. Results in the host institution did not differ from 5 beta sites (n = 215, external validity). MISTELS scores correlated with a highly reliable validated intraoperative rating of technical skill during laparoscopic cholecystectomy (n = 19, r = 0.81, P < 0.0004; concurrent validity). Novice laparoscopists were randomized to practice/no practice of the transfer drill for 4 weeks. Improvement in intracorporeal suturing skill was significantly related to practice but not to baseline ability, career goals, or gender (P < 0.001). Conclusion:MISTELS is a practical and inexpensive inanimate system developed to teach and measure technical skills in laparoscopy. This system is reliable, valid, and a useful educational tool.


Surgery | 2004

Development and validation of a comprehensive program of education and assessment of the basic fundamentals of laparoscopic surgery

Jeffrey H. Peters; Gerald M. Fried; Lee L. Swanstrom; Nathaniel J. Soper; Lelan F. Sillin; Bruce D. Schirmer; Kaaren I. Hoffman

IN THE LATE 1990S THE Society of American Gastrointestinal Endoscopic Surgery (SAGES) formed a committee (Fundamentals of Laparoscopic Surgery or FLS) and charged it to develop educational materials covering the basic fundamentals of laparoscopic surgery. Four major principles guided the committee’s developmental process. First, comprehensive coverage of the domain of basic laparoscopy was seen as involving two components: one cognitive (declarative knowledge); and the other psychomotor (procedural skill). Second, the focus of the program was to be on the educational material considered unique to laparoscopy and not on material normally encountered during open surgical training. Third, in accordance with the idea of basic fundamentals, any content specific to a particular anatomic location or to a specific laparoscopic procedure was to be avoided. And fourth, the program was to contain mechanisms for assessment as well as for didactic instruction. The overall goal of the FLS program was to ‘‘teach a standard set of cognitive and psychomotor skills to practitioners of laparoscopic surgery’’ in the belief that knowledge and application of these fundamentals would help ‘‘ensure a minimal standard of care for all patients undergoing laparoscopic surgery.’’ The didactic learning modules are


Annals of Surgery | 2006

Biologic Prosthesis Reduces Recurrence After Laparoscopic Paraesophageal Hernia Repair: A Multicenter, Prospective, Randomized Trial

Brant K. Oelschlager; Carlos A. Pellegrini; John G. Hunter; Nathaniel J. Soper; Michael Brunt; Brett C. Sheppard; Blair A. Jobe; Nayak L. Polissar; Lee M. Mitsumori; James A. Nelson; Lee L. Swanstrom

Objective:Laparoscopic paraesophageal hernia repair (LPEHR) is associated with a high recurrence rate. Repair with synthetic mesh lowers recurrence but can cause dysphagia and visceral erosions. This trial was designed to study the value of a biologic prosthesis, small intestinal submucosa (SIS), in LPEHR. Methods:Patients undergoing LPEHR (n = 108) at 4 institutions were randomized to primary repair −1° (n = 57) or primary repair buttressed with SIS (n = 51) using a standardized technique. The primary outcome measure was evidence of recurrent hernia (≥2 cm) on UGI, read by a study radiologist blinded to the randomization status, 6 months after operation. Results:At 6 months, 99 (93%) patients completed clinical symptomatic follow-up and 95 (90%) patients had an UGI. The groups had similar clinical presentations (symptom profile, quality of life, type and size of hernia, esophageal length, and BMI). Operative times (SIS 202 minutes vs. 1° 183 minutes, P = 0.15) and perioperative complications did not differ. There were no operations for recurrent hernia nor mesh-related complications. At 6 months, 4 patients (9%) developed a recurrent hernia >2 cm in the SIS group and 12 patients (24%) in the 1° group (P = 0.04). Both groups experienced a significant reduction in all measured symptoms (heartburn, regurgitation, dysphagia, chest pain, early satiety, and postprandial pain) and improved QOL (SF-36) after operation. There was no difference between groups in either pre or postoperative symptom severity. Patients with a recurrent hernia had more chest pain (2.7 vs. 1.0, P = 0.03) and early satiety (2.8 vs. 1.3, P = 0.02) and worse physical functioning (63 vs. 72, P = 0.03 per SF-36). Conclusions:Adding a biologic prosthesis during LPEHR reduces the likelihood of recurrence at 6 months, without mesh-related complications or side effects.


Diseases of The Colon & Rectum | 1995

Impact of pneumoperitoneum on trocar site implantation of colon cancer in hamster model

Daniel B. Jones; Li Wu Guo; Mary K. Reinhard; Nathaniel J. Soper; Gordon W. Philpott; Judith M. Connett; James W. Fleshman

BACKGROUND: Numerous anecdotal reports have documented the spread of colon cancer to trocar sites after laparoscopic-assisted colectomy. We hypothesized that the pneumoperitoneum of laparoscopy potentiated tumor adherence to trocar sites. PURPOSE: This study was designed to determine the affect of CO2pneumoperitoneum on the rate of tumor implantation at trocar sites. METHODS: Viable GW-39 human colon cancer cells were injected into the abdominal cavity of hamsters (2 × 106cells/hamster). A midline laparotomy, insertion of four 5-mm trocars, injection of viable cells into the mesentery of the cecum, and free peritoneal cavity was performed in two groups: one control group (41) who did not receive a pneumoperitoneum and a comparison group (50) who underwent pneumoperitoneum for ten minutes at an insufflation pressure of 10 mmHg. Animals were killed at six weeks, and hematoxylin and eosin-stained sections of trocar wounds, midline wound, small intestine, cecum, liver, and lung were examined by a veterinary pathologist, who was blinded to operation. RESULTS: Pneumoperitoneum increased tumor implantation in the cecal mesentery and the midline incision (P<0.05) but did not effect recurrence in the liver, lung, or jejunum. Trocar site implantation tripled with the addition of pneumoperitoneum (26vs.75 percent) (P<0.0001). CONCLUSION: Pneumoperitoneum increased implantation of free intra-abdominal cancer cells at wound sites on the abdominal wall or within the abdominal cavity in this animal model. The use of pneumoperitoneum during laparoscopy in patients with colon cancer should only be performed in a protocol setting to evaluate the effect of pneumoperitoneum on the treatment of cancer.


Journal of The American College of Surgeons | 2011

Biologic Prosthesis to Prevent Recurrence after Laparoscopic Paraesophageal Hernia Repair: Long-term Follow-up from a Multicenter, Prospective, Randomized Trial

Brant K. Oelschlager; Carlos A. Pellegrini; John G. Hunter; Michael Brunt; Nathaniel J. Soper; Brett C. Sheppard; Nayak L. Polissar; Moni B. Neradilek; Lee M. Mitsumori; Charles A. Rohrmann; Lee L. Swanstrom

BACKGROUND In 2006, we reported results of a randomized trial of laparoscopic paraesophageal hernia repair (LPEHR), comparing primary diaphragm repair (PR) with primary repair buttressed with a biologic prosthesis (small intestinal submucosa [SIS]). The primary endpoint, radiologic hiatal hernia (HH) recurrence, was higher with PR (24%) than with SIS buttressed repair (9%) after 6 months. The second phase of this trial was designed to determine the long-term durability of biologic mesh-buttressed repair. METHODS We systematically searched for the 108 patients in phase I of this study to assess current clinical symptoms, quality of life (QOL) and determine ongoing durability of the repair by obtaining a follow-up upper gastrointestinal series (UGI) read by 2 radiologists blinded to treatment received. HH recurrence was defined as the greatest measured vertical height of stomach being at least 2 cm above the diaphragm. RESULTS At median follow-up of 58 months (range 42 to 78 mo), 10 patients had died, 26 patients were not found, 72 completed clinical follow-up (PR, n = 39; SIS, n = 33), and 60 repeated a UGI (PR, n = 34; SIS, n = 26). There were 20 patients (59%) with recurrent HH in the PR group and 14 patients (54%) with recurrent HH in the SIS group (p = 0.7). There was no statistically significant difference in relevant symptoms or QOL between patients undergoing PR and SIS buttressed repair. There were no strictures, erosions, dysphagia, or other complications related to the use of SIS mesh. CONCLUSIONS LPEHR results in long and durable relief of symptoms and improvement in QOL with PR or SIS. There does not appear to be a higher rate of complications or side effects with biologic mesh, but its benefit in reducing HH recurrence diminishes at long-term follow-up (more than 5 years postoperatively) or earlier.


Journal of The American College of Surgeons | 1997

Staging laparoscopy with laparoscopic ultrasonography: optimizing resectability in hepatobiliary and pancreatic malignancy

Mark P. Callery; Steven M. Strasberg; Gerard M. Doherty; Nathaniel J. Soper; Jeffrey A. Norton

BACKGROUND Open laparotomy has traditionally been required to stage hepatobiliary and pancreatic (HBP) cancers accurately. For unresectable patients, costs and morbidity have been high. Today, laparoscopy alone or combined with laparoscopic ultrasonography (LUS) is being examined for its value in defining the extent of malignancy. STUDY DESIGN We have analyzed the effect of routine implementation of this new staging technique in our HBP center. Staging laparoscopy (SL) with LUS was performed in 50 consecutive patients with HBP malignancies. All patients were considered to have resectable tumors as determined by traditional preoperative staging modalities. Primary tumors were located in the liver (n = 7), biliary tract (n = 11), or pancreas (n = 32). An average of 2.7 preoperative studies per patient were performed prior to SL-LUS. RESULTS Staging laparoscopy with laparoscopic ultrasonography predicted resectable tumors in 28 patients (56%). At laparotomy, 26 of 28 were actually resectable: the false-negative rate was 4%. Staging laparoscopy with laparoscopic ultrasonography indicated unresectability in 22 patients (44%). Staging laparoscopy alone demonstrated previously unrecognized occult metastases in 11 patients (22%). In 11 other patients (22%) in whom SL alone was negative, LUS established unresectability from vascular invasion (n = 5), lymph node metastases (n = 5), or intraparenchymal hepatic tumor (n = 1). All cases of unresectability due to vascular invasion were validated by laparotomy. Five of six lymph node or hepatic metastases were proved histologically by LUS-guided needle biopsy rather than laparotomy. CONCLUSIONS Unnecessary laparotomy can be safely avoided by SL-LUS in many patients with HPB malignancies, reducing costs and morbidity.


Journal of Gastrointestinal Surgery | 2002

Absence of Gastroesophageal Reflux Disease in a Majority of Patients Taking Acid Suppression Medications After Nissen Fundoplication

Reginald V. Lord; Anna Kaminski; Stefan Öberg; David J. Bowrey; Jeffrey A. Hagen; Steven R. DeMeester; Lelan F. Sillin; Jeffrey H. Peters; Peter F. Crookes; Tom R. DeMeester; John G. Hunter; Reginald C. W. Bell; Nathaniel J. Soper; L. W. Way

Recent studies have shown that many patients use acid suppression medications after antireflux surgery. The aim of this study was to determine the frequency of gastroesophageal reflux disease in a cohort of surgically treated patients with postoperative symptoms and a high prevalence of acid suppression medication use. The study group consisted of 86 patients who had symptoms following Nissen fundoplication that were sufficient to merit evaluation with 24-hour distal esophageal pH monitoring. All completed a detailed symptom questionnaire. The mean postoperative follow-up period was 28 months (median 18 months). Thirty-seven patients (43%) were taking acid suppression medications after fundoplication. Only 23% (20 of 86) of all the patients and only 24% (9 of 37) of those taking acid suppression medications had abnormal esophageal acid exposure on the 24-hour pH study. Heartburn and regurgitation were the only symptoms that were significantly associated with an abnormal pH study. Endoscopic assessment of the fundoplication was the most significant factor associated with an abnormal pH study. Multivariable logistic regression analysis showed that patients with a disrupted, abnormally positioned fundoplication had a 52.6 times increased risk of abnormal esophageal acid exposure. Most patients who use acid suppression medications after antireflux surgery do not have abnormal esophageal acid exposure, and the use of these medications is thus often inappropriate. Because of the limited predictive power of symptoms, objective evidence of reflux disease should be obtained before prescribing acid suppression medication for patients who have undergone antireflux surgery.


Journal of Gastrointestinal Surgery | 2003

Laparoscopic paraesophageal hernia repair, a challenging operation: Medium-term outcome of 116 patients

Sergio Diaz; L. Michael Brunt; Mary E. Klingensmith; P. Frisella; Nathaniel J. Soper

Laparoscopic paraesophageal hernia repairs performed in 116 patients between 1992 and 2001 were pro-spectively analyzed. Perioperative outcomes were assessed and follow-up was performed under protocol. There were 85 female and 31 male patients who had a mean (± SD)ageof65 ± 13 years and an American Society of Anesthesiology score of 2.3 ± 0.6. All but two patients underwent an antireflux procedure. Gastropexy was performed in 48 patients, an esophageal lengthening procedure in six patients, and prosthetic closure of the hiatus in six patients. Major complications occurred in five patients (4.3%) with two postoperative deaths (1.7%). Mean follow-up was 30 ± 25 months; 96 patients (83%) have been followed for more than 6 months. Among these patients, 73 (76%) are asymptomatic, 11 (11%) have mild symptoms, and 12 (13%) take antacid medications. Protocol barium esophagograms were obtained in 69% of patients at 6 to 12 months’ follow-up. Recurrence of hiatal hernia was documented in 21 patients (22% overall and in 32% of those undergoing contrast studies). Reoperation has been performed in three patients (3 %). When only the patients with recurrent hiatal hernias are considered, 13 (62 %) are symptomatic but only six (28%) require medication for symptoms. Laparoscopic paraesophageal hernia repair is generally safe, even in this high-risk group. This study confirms a relatively high incidence of recurrent hiatal abnormalities after paraesophageal hernia repair; however, most recurrent hiatal hernias are small and only 3% have required reoperation. Protocol esophagograms detect recurrences that are minimally symptomatic. Improved techniques must be devised to improve the long-term outcomes of laparoscopic paraesophageal hernia repair.


Surgical laparoscopy & endoscopy | 1999

Meta-analysis of randomized controlled trials comparing laparoscopic and open appendectomy

Jane Garbutt; Nathaniel J. Soper; William D. Shannon; Anna C. Botero; Benjamin Littenberg

We performed a meta-analysis to determine whether laparoscopic or open appendectomy gives better outcomes for patients with suspected acute appendicitis. Studies were selected from the MEDLINE database, personal files, and meeting abstracts. Eleven of 21 randomized controlled trials were included in the meta-analysis. Pooled effect size estimates were calculated using a random effects model. Laparoscopic appendectomy reduced time to full functioning by 5.48 days (95% confidence interval [CI] 3.70 to 7.26; p < 0.001), improved postoperative pain at 24 hours measured by a visual analog scale from 0 to 10 by 1.19 points (95% CI -2.14 to -0.24 points; p=0.014), and decreased the absolute risk for wound infection by 3.2% (95% CI -5.6% to -0. 8%; p=0.009). Operating time was increased by 17.12 min (95% CI 14.19 to 20.03; p < 0.0001). There was no difference between the two surgeries for length of hospital stay, readmission rate, and intra-abdominal abscess formation. Laparoscopic appendectomy improves patient outcomes.

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Lee L. Swanstrom

Providence Portland Medical Center

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Daniel B. Jones

Beth Israel Deaconess Medical Center

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Justin S. Wu

Washington University in St. Louis

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