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Dive into the research topics where Christine J. Ren is active.

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Featured researches published by Christine J. Ren.


Journal of Gastrointestinal Surgery | 2004

Serum fat-soluble vitamin deficiency and abnormal calcium metabolism after malabsorptive bariatric surgery

Guy H Slater; Christine J. Ren; Niccole Siegel; Trudy Williams; Di Barr; Barrie Wolfe; Kevin Dolan; George Fielding

Weight loss after biliopancreatic diversion or duodenal switch is due to decreased calorie absorption secondary to fat malabsorption. Fat malabsorption may also cause essential fat-soluble vitamin deficiencies, which may have severe clinical consequences and alter calcium metabolism. Serum vitamins A, D, E, and K, zinc, parathyroid hormone, corrected calcium, and alkaline phosphatase levels were measured in a cohort of patients who had previously undergone biliopancreatic diversion. Two bariatric surgery units were involved in the study: New York University School of Medicine (New York, NY), and the Wesley Medical Center (Brisbane, Australia). A total of 170 patients completed the study. The incidence of vitamin A deficiency was 69%, vitamin K deficiency 68%, and vitamin D deficiency 63% by the fourth year after surgery. The incidence of vitamin E and zinc deficiency did not increase with time after surgery. The incidence of hypocalcemia increased from 15% to 48% over the study period with a corresponding increase in serum parathyroid hormone values in 69% of patients in the fourth postoperative year. There is a progressive increase in the incidence and severity of hypovitaminemia A, D, and K with time after biliopancreatic diversion and duodenal switch. Calcium metabolism is affected with an increasing incidence of secondary hyperparathyrodisim and evidence of increased bone resorption in 3% of patients. Long-term nutritional monitoring is necessary after malabsorptive operations for morbid obesity.


Obesity Surgery | 2004

Impact of patient follow-up on weight loss after bariatric surgery

Roy Shen; Giovanni S. Dugay; Kavitha Rajaram; Izumi Cabrera; Niccole Siegel; Christine J. Ren

Background: Postoperative follow-up after bariatric surgery is important. Because of the need for adjustments, follow-up after gastric banding may have a greater impact on weight loss than after Roux-en-Y gastric bypass.We reviewed all patients at 1 year after these two operations. Methods: During the first year after surgery, laparoscopic adjustable gastric banding (LAGB) patients were followed every 4 weeks and Roux-en-Y gastric bypass (RYGBP) patients were followed at 3 weeks postoperatively and then every 3 months.The number of follow-up visits for each patient was calculated, and 50% compliance for follow-up and weight loss was compared. Results: Between October 2000 and September 2002, 216 LAGB and 139 RYGBP operations were performed. Of these patients, 186 LAGB patients and 115 RYGBP patients were available for 1-year follow-up. Age and BMI were similar for each group. Overall excess weight loss (EWL) after LAGB was 44.5%. 130 (70%) returned 6 or less times in the first year and achieved 42% EWL. 56 patients (30%) returned more than 6 times and had 50% EWL (P=0.005). Overall %EWL after RYGBP was 66.1%. 53 patients (46%) returned 3 or less times in the first year, achieving 66.1% EWL. 62 patients (54%) returned more than 3 times after surgery and achieved 67.6% EWL (P=NS). Conclusion: Patient follow-up plays a significant role in the amount of weight lost after LAGB, but not after RYGBP. Patient motivation and surgeon commitment for long-term follow-up is critical for successful weight loss after LAGB surgery.


American Journal of Surgery | 2002

US experience with the LAP-BAND system

Christine J. Ren; Santiago Horgan; Jaime Ponce

Laparoscopic adjustable gastric banding is the most commonly performed operation for morbid obesity in Europe and Australia and has been shown to result in significant long-term weight loss. The US Food and Drug Administration (FDA)-monitored clinical trial results with the LAP-BAND system (INAMED Health, Santa Barbara, CA) did not reproduce the results of studies performed elsewhere in the world. This article reviews data from the first and second FDA clinical trials as well as data from continuing US clinical experience. Four American surgeons at 4 centers have performed more than 500 LAP-BAND procedures not included in the first 2 FDA clinical trials. Of these patients, 115 have been followed for at least 9 months, and 43 have been followed for at least 12 months. A retrospective analysis of prospective data gathered from these patients is presented. The percent excess weight loss was 35.6% at 9 months and 41.6% at 12 months. The average body mass index decreased from 47.5 to 38.8 in 9 months and from 47.5 to 37.3 in 12 months. There were no deaths related to the insertion of the device. Of 15 complications requiring operative management (13%) in 12 patients, there were 8 port displacements or tubing breaks (7%), 2 elective explantations (2%), 2 cases of gastric prolapse (2%), 1 gastric pouch dilatation (<1%), 1 port abscess (<1%), and 1 hemorrhage (<1%). Clinical experience with the LAP-BAND system in the United States shows the device to be a safe and effective treatment for morbid obesity, with results comparable to the international data. The combination of proper surgical technique and close patient follow-up with frequent band adjustments, performed in a comprehensive bariatric program setting, may make the LAP-BAND system a powerful surgical tool in the treatment of morbid obesity.


Obesity Surgery | 2004

Endoscopy Plays an Important Preoperative Role in Bariatric Surgery

Ravi N Sharaf; Elizabeth H. Weinshel; Edmund J. Bini; Jonathan Rosenberg; Alex Sherman; Christine J. Ren

Background: The role of upper endoscopy (EGD) in obese patients prior to bariatric surgery is controversial. The aim of this study was to evaluate the diagnostic yield and cost of routine EGD before bariatric surgery. Methods: The medical records of consecutive obese patients who underwent EGD prior to bariatric surgery between May 2000 and September 2002 were reviewed. Two experienced endoscopists reviewed all EGD reports, and findings were divided into 4 groups based on predetermined criteria: group 0 (normal study), group 1 (abnormal findings that neither changed the surgical approach nor postponed surgery), group 2 (abnormal findings that changed the surgical approach or postponed surgery), and group 3 (results that were an absolute contraindication to surgery). Clinically important findings included lesions in groups 2 and 3. The cost of EGD (US


Journal of Pediatric Surgery | 2008

An update on 73 US obese pediatric patients treated with laparoscopic adjustable gastric banding: comorbidity resolution and compliance data

Evan P. Nadler; Heekoung Youn; Christine J. Ren; George Fielding

430.72) was estimated using the endoscopist fee under Medicare reimbursement. Results: During the 28-month study period, 195 patients were evaluated by EGD prior to bariatric surgery. One or more lesions were identified in 89.7% of patients, with 61.5% having a clinically important finding. The prevalence of endoscopic findings using the classification system above was as follows: group 0 (10.3%), group 1 (28.2%), group 2 (61.5%), and group 3 (0.0%). Overall, the most common lesions identified were hiatal hernia (40.0%), gastritis (28.7%), esophagitis (9.2%), gastric ulcer (3.6%), Barretts esophagus (3.1%), and esophageal ulcer (3.1%). The cost of performing routine endoscopy on all patients prior to bariatric surgery was US


Journal of Laparoendoscopic & Advanced Surgical Techniques | 2003

Laparoscopic Adjustable Gastric Banding: Surgical Technique

Christine J. Ren; George Fielding

699.92 per clinically important lesion detected. Conclusions: Routine upper endoscopy before bariatric surgery has a high diagnostic yield and has a low cost per clinically important lesion detected.


Surgical Endoscopy and Other Interventional Techniques | 2005

U.S. experience with 749 laparoscopic adjustable gastric bands: intermediate outcomes

Manish Parikh; George Fielding; Christine J. Ren

BACKGROUND Adolescent obesity continues to present one of the most difficult and important challenges for both the pediatric and adult medical communities. Evidence is mounting that bariatric surgery is the only reliable method for substantial and sustainable weight loss; however, the debate continues with regard to the optimal surgical procedure for both adolescents and adults. Although most US adult bariatric surgeons prefer the gastric bypass, our institution has demonstrated equivalent weight loss with significantly less morbidity using laparoscopic adjustable gastric banding (LAGB) in both adults and adolescents. This analysis is an update of our results in our first 73 patients, including resolution of comorbid conditions and compliance data. METHODS All adolescents aged 13 to 17 years who have undergone LAGB at our institution have been entered into our prospectively collected database since September 2001 and were reviewed. Data collected preoperatively included age, sex, race, body mass index (BMI), and presence of comorbid conditions. Postoperatively recorded data included length of stay, operative morbidity, need for reoperation, percentage of excess weight loss (%EWL), and BMI at 3-month intervals; status of any comorbid conditions, and number of postoperative visits and band adjustments. RESULTS Seventy-three adolescents aged 13 to 17 years (mean, 15.8 +/- 1.2 years) have undergone LAGB at our institution since September, 2001. Of these, 54 were female and 19 were male. The mean preoperative weight was 298 lb, with a BMI of 48 kg/m(2). The %EWL at 6 months, 1 year, and 2 years postoperatively was 35% +/- 16%, 57% +/- 23%, and 61% +/- 27%, respectively. One patient experienced a gastric perforation after a reoperation for band replacement because of a slip. One additional patient requested band removal because of restriction intolerance after a slip. A total of 6 patients developed band slippage, and 3 patients developed symptomatic hiatal hernias. Nutritional complications included asymptomatic iron deficiency in 13 patients, asymptomatic vitamin D deficiency in 4 patients, and mild subjective hair loss in 14 patients. In 21 patients who entered our Food and Drug Administration-approved study and had reached 1-year follow-up, there were 51 identified comorbid conditions. Of these, 35 (68.5%) were completely resolved, 9 (17.5%) were improved, 5 (10%) were unchanged, and 2 (4%) were aggravated after 1 year. Of 50 initial patients who underwent surgery more than 1 year ago, 2 patients lived a large distance from our institution, where band maintenance is being performed locally, and thus, the patients were excluded from the analysis. Two patients were lost to follow-up in the first year, and 3 patients were lost to follow-up in the second year, for an overall compliance rate of at least 89.5%. The mean number of office visits was 10 +/- 3 in the first year, and the mean number of adjustments was 6 +/- 2. CONCLUSIONS Laparoscopic adjustable gastric banding continues to represent an attractive treatment strategy for morbidly obese pediatric patients with a %EWL of more than 55% at both 1- and 2-year follow-up, with minimal morbidity compared with the gastric bypass. Furthermore, the weight loss associated with LAGB provides excellent resolution or improvement of comorbid conditions. Although there is a necessary commitment by the patient that involves frequent office visits and band adjustments, adolescents are entirely capable of this commitment, and noncompliance should not be a reason to dissuade adolescents from having LAGB. It remains, in our opinion, the optimal surgical option for pediatric patients with morbid obesity.


Obesity Surgery | 2005

Laparoscopic Bariatric Surgery in Super-obese Patients (BMI>50) is Safe and Effective: A Review of 332 Patients

Manish Parikh; Roy Shen; Matthew Weiner; Niccole Siegel; Christine J. Ren

Laparoscopic adjustable gastric banding is an effective and safe surgical treatment for morbid obesity. Initial experience with the Lap-Band system (Inamed Health, Santa Barbara, California) in the United States and Australia has demonstrated that surgical technique can affect outcomes in terms of weight loss, quality of life, and complication rates. Placement of the gastric band by means of the perigastric technique is associated with high rates of gastric prolapse, food intolerance, and weight loss failure that frequently lead to band explantation. In the pars flaccida technique, band placement higher on the stomach results in the formation of a smaller pouch and lower rates of gastric prolapse, which may contribute to greater weight loss and improved quality of life. This article describes the technical aspects of the pars flaccida approach in the laparoscopic placement of adjustable gastric bands.


Surgical Endoscopy and Other Interventional Techniques | 2004

Favorable early results of gastric banding for morbid obesity: the American experience

Christine J. Ren; M. Weiner; Jeff W. Allen

Background:Laparoscopic adjustable gastric band (LAGB) has consistently been shown to be a safe and effective treatment for morbid obesity, especially in Europe and Australia. Data from the U.S. regarding the LAGB has been insufficient. This study reveals our experience with 749 primary LAGB over a 3-year period in a U.S. university teaching hospital.Methods:All data was prospectively collected and entered into an electronic registry. Characteristics evaluated for this study include preoperative age, BMI, gender, race, conversion rate, operative time, hospital stay, percent excess weight loss (%EWL) and postoperative complications. Annual esophagrams were performedResults:From July 2001 through September 2004, 749 patients (531 females, 218 males) underwent LAGB for the treatment of morbid obesity. There were 630 Caucasians, 61 African-Americans, and 49 Latin Americans, with a mean age of 42.3 (range 18, 72 years) and mean BMI of 46.0 ± 7.0 (range 35, 91.5 kg/m2). There was one conversion to open (0.1%). Median operative time and hospital stay were 60 minutes and 23 hours, respectively. The mean %EWL at 1 year, 2 years, and 3 years was 44.4 (±17.8), 51.8 (±20.9), and 52.0 (±19.6), respectively. There were no mortalities. Postoperative complications occurred in 12.8% of patients: 1.5% acute postoperative band obstruction, 0.9% wound infection, 2.9% gastric prolapse (“slip”), 2.0% concentric pouch dilatation (without slip), 0.8% aspiration pneumonia, 2.4% port/tubing problems, 0.3% severe esophageal dilatation/dysmotility (reversible), and 1.5% overall band removal.Conclusion:These American results substantiate the data from abroad that LAGB is a safe and effective treatment for morbid obesity.


Journal of The American College of Surgeons | 2009

Laparoscopic adjustable gastric banding for morbidly obese adolescents affects android fat loss, resolution of comorbidities, and improved metabolic status.

Evan P. Nadler; Shivani Reddy; Anthony Isenalumhe; Heekoung Youn; Valerie Peck; Christine J. Ren; George Fielding

Background: Bariatric surgery in super-obese patients (BMI >50 kg/m2) can be challenging because of difficulties in exposure of visceral fat, retracting the fatty liver, and strong torque applied to instruments, as well as existing co-morbidities. Methods: A retrospective review of super-obese patients who underwent laparoscopic adjustable gastric banding (LAGB n=192), Roux-en-Y gastric bypass (RYGBP n=97), and biliopancreatic diversion with/without duodenal switch (BPD n= 43), was performed. 30day peri-operative morbidity and mortality were evaluated to determine relative safety of the 3 operations. Results: From October 2000 through June 2004, 331 super-obese patients underwent laparoscopic bariatric surgery, with mean BMI 55.3 kg/m2. Patients were aged 42 years (13-72), and 75% were female. When categorized by opertaion (LAGB, RYGBP, BPD), the mean age, BMI and gender were comparable. 6 patients were converted to open (1.8%). LAGB had a 0.5%, RYGBP 2.1% and BPD 7.0% conversion rate (P=0.02, all groups). Median operative time was 60 min for LAGB, 130 min for RYGBP and 255 min for BPD (P<0.001, all groups). Median length of stay was 24 hours for LAGB, 72 hours for RYGBP, and 96 hours for BPD (P <0.001). Mean %EWL for the LAGB was 35.3±12.6, 45.8±19.4, and 49.5±18.6 with follow-up of 87%, 76% and 72% at 1, 2 and 3 years, respectively. Mean %EWL for the RYGBP was 57.7±15.4, 54.7±21.2, and 56.8±21.1 with follow-up of 76%, 33% and 54% at 1, 2 and 3 years, respectively. Mean %EWL for the BPD was 60.6±15.9, 69.4±13.0 and 77.4±11.9 with follow-up of 79%, 43% and 47% at 1, 2 and 3 years, respectively. The difference in %EWL was significant at all time intervals between the LAGB and BPD (P<0.004). However, there was no significant difference in %EWL between LAGB and RYGBP at 2 and 3 years. Overall perioperative morbidity occurred in 27 patients (8.1%). LAGB had 4.7% morbidity rate, RYGBP 11.3%, and BPD 16.3% (P=0.02, all groups). There were no deaths. Conclusion: Laparoscopic bariatric surgery is safe in super-obese patients. LAGB, the least invasive procedure, resulted in the lowest operative times, the lowest conversion rate, the shortest hospital stay and the lowest morbidity in this high-risk cohort of patients. Rates of all parameters studied increased with increasing procedural complexity. However, the difference in %EWL between RYGBP and LAGB at 2 and 3 years was not statistically significant.

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Evan P. Nadler

Children's National Medical Center

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