Small-bowel obstruction secondary to internal hernia is a known postoperative complication of lap... more Small-bowel obstruction secondary to internal hernia is a known postoperative complication of laparoscopic Roux-en-Y gastric bypass (RYGBP). Petersen's defect is the most common site of postoperative internal herniation. The authors describe their technique of closure of the infracolic component of the Petersen's defect using continuous non-absorbable suture material. The method has been used successfully to reduce the incidence of internal herniation after laparoscopic RYGBP.
... Composites Science and Technology 69(7-8):1101-7. Paya, I., Yepes, V., Gonzalez-Vidosa, F. &a... more ... Composites Science and Technology 69(7-8):1101-7. Paya, I., Yepes, V., Gonzalez-Vidosa, F. & Hospitaler, A. 2008. Multiobjective optimization of concrete frames by simulated annealing. Computer-Aided Civil and Infrastruc-ture Engineering 23(8):596-610. ...
... Furthermore, applied fire effect after applying the external load to the structure is an ... ... more ... Furthermore, applied fire effect after applying the external load to the structure is an ... Finally, thecreep and shrinkage strain might be considered in the future studies ... Finite Element Analysis of Fibre Reinforce Concrete Beam Subject to High Temperature by Using EURO-Code ...
JSLS : Journal of the Society of Laparoendoscopic Surgeons / Society of Laparoendoscopic Surgeons
Laparoscopic fundoplication has revolutionized the surgical treatment of gastroesophageal reflux ... more Laparoscopic fundoplication has revolutionized the surgical treatment of gastroesophageal reflux disease. Despite improvements in the technique of fundoplication, persistent dysphagia remains a significant cause of postoperative morbidity. Causes of persistent postoperative dysphagia were analyzed in a consecutive series of 167 patients after laparoscopic Nissen fundoplication. Short gastric vessel division and its effect on postoperative dysphagia were analyzed. Follow-up was possible in 139 patients (83%). The mean follow-up period was 27 +/- 21 months. Nine patients (6%) had persistent (moderate to severe) dysphagia, and 33 patients (24%) had mild dysphagia. The satisfaction score among patients with persistent dysphagia was significantly lower than that in patients with mild dysphagia (P < 0.0002). On the other hand, the satisfaction rate among patients with mild dysphagia and those who are asymptomatic was similar. Manometry, performed in 7 of 9 persistent dysphagia patients...
Large bowel obstruction with perforation is an anomalous presentation of pancreatic tail carcinom... more Large bowel obstruction with perforation is an anomalous presentation of pancreatic tail carcinoma. Pancreatic cancer is often difficult to diagnose clinically and is especially furtive when it is located in the tail of the pancreas. We describe a patient who presented with large bowel obstruction due to splenic flexure mass which proved to be due to pancreatic mucinous adenocarcinoma. Pancreatic adenocarcinoma can rarely have the same presentation as colon cancer, and should therefore be considered in the differential diagnosis of large bowel obstruction.
Postoperative pain after laparoscopic cholecystectomy (LC) is generally less than open cholecyste... more Postoperative pain after laparoscopic cholecystectomy (LC) is generally less than open cholecystectomy; however, the postoperative shoulder and abdominal pain experienced by patients still causes preventable distress. Intraperitoneal irrigation of the diaphragmatic surface and gallbladder fossa using normal saline, bupivacaine, or lignocaine may effectively control visceral abdominal pain after an LC. Two hundred patients with similar demographics undergoing elective LC were randomized to one of four groups of 50 patients each, including Group A placebo control, Group B with isotonic saline irrigation, Group C with bupivacaine irrigation, and Group D with lignocaine irrigation. All patients received preperitoneal abdominal wall infiltration with 0.25 per cent bupivacaine to control parietal (somatic) abdominal pain. The visual analogue and verbal rating pain scores at 0, 4, 8, 12 and 24 hours for both shoulder and abdominal pain were recorded in a prospective double-blind fashion at four points during the first 24 postoperative hours. Analgesia requirements, vital signs, blood glucose, and incidence of nausea and vomiting were also recorded. Patients in each group demonstrated a significant difference in visual analogue and verbal rating pain scores and analgesic consumption when compared with controls. Lignocaine controlled pain significantly better than saline or bupivacaine. Bowel function recovery was similar in all patients, and there were no significant complications. We conclude that intraperitoneal irrigation with either saline, bupivacaine, or lignocaine can significantly reduce visceral abdominal pain after LC. Lignocaine was the most efficacious local anesthetic in this trial and has a high safety profile when used at recommended doses.
... In addition, its use has been increasing for the repairing, strengthening and replacement of ... more ... In addition, its use has been increasing for the repairing, strengthening and replacement of old structures. ... Applied Soft Computing. ... [65] Ghiasi H, Fayazbakhsh K, Pasini D, Lessard L. Optimum stacking sequence design of composite materials Part II: Variable stiffness design. ...
With successful surgical treatment of gastroesophageal reflux disease (GERD), there is interest i... more With successful surgical treatment of gastroesophageal reflux disease (GERD), there is interest in understanding the anti-reflux barrier and its mechanisms of failure. To date, the potential use of vector volumes to predict the DeMeester score has not been adequately explored. 627 patients in the referral database received esophageal manometry and ambulatory 24-hour pH monitoring. Study data included LES resting pressure (LESP), overall LES length (OL) and abdominal length (AL), total vector volume (TVV) and intrabdominal vector volume (IVV). In cases where LESP, TVV or IVV were all below normal, there was an 81.4 % probability of a positive DeMeester score. In cases where all three were normal, there was an 86.9 % probability that the DeMeester score would be negative. Receiver-operating characteristics (ROC) for LESP, TVV and IVV were nearly identical and indicated no useful cut-off values. Logistic regression demonstrated that LESP and IVV had the strongest association with a pos...
To determine predictive factors for postoperative dysphagia after laparoscopic myotomy for achala... more To determine predictive factors for postoperative dysphagia after laparoscopic myotomy for achalasia. Logistic regression was used to investigate the possible association between the response (postoperative dysphagia, with two levels: none/mild and moderate/severe) and several plausible predictive factors. Eight patients experienced severe or moderate postoperative dysphagia. The logistic regression revealed that only the severity of preoperative dysphagia (with four levels: mild, moderate, severe, and liquid) was a marginally significant (P=0.0575) predictive factor for postoperative dysphagia. The severity of postoperative dysphagia is strongly associated with preoperative dysphagia. Preoperative symptomatology can significantly impact patient outcome.
Background: Self-expanding metal and plastic esophageal stents (SEMS and SEPS, respectively) are ... more Background: Self-expanding metal and plastic esophageal stents (SEMS and SEPS, respectively) are used in conjunction with chemoradiation for palliation of malignant dysphagia. To date, the dosimetric effects of stents undergoing proton radiotherapy are not known. Study aim: To investigate the proton radiotherapy dose perturbations caused by esophageal stents of varying designs and materials undergoing external beam treatment for esophageal cancer. Patients and methods: Simulated clinical protocol. Solid acrylic phantom was used to mimic the esophageal tissue environment. Stents made of nitinol, stainless steel and polyester were tested. Proton beam dose of 2 Gy-E was delivered to each stent in a single anterior to posterior field. Film and image based evidence of dose perturbation were main outcomes measured. Results: Only the stainless steel and plastic stents demonstrated slight overall dose attenuations (- 0.5 % and - 0.4 %, respectively). All the nitinol-based stents demonstrated minimal overall dose perturbations ranging from 0.0 % to 1.2 %. Negligible dose perturbations were observed on each of the stent surfaces proximal to the radiation source, ranging from - 0.8 % (stainless steel stent) to 1.0 % (nitinol stent). Negligible dose effects were also observed on the distal surfaces of each stent ranging from - 0.5 % (plastic and stainless steel stents) to 1.0 % (nitinol stent). Conclusion: Proton radiotherapy dose perturbations caused by stents of varying designs and material composition are negligible. Negligible dose perturbation is in keeping with the inherent advantage of proton therapy over traditional radiotherapy composed of photons - given its relative large mass, protons have little side scatter.
As antireflux surgery has been used increasingly for gastroesophageal reflux disease (GERD), a ne... more As antireflux surgery has been used increasingly for gastroesophageal reflux disease (GERD), a need has arisen for an accurate method to assess esophageal length. There are a number of preoperative tests that can help surgeons to establish the presence of a short esophagus, but intraoperative assessment after esophageal mobilization is the standard method. In this era of laparoscopic surgery, the surgeon mobilizes the esophagus extensively from the abdomen and then determines if mobilization is sufficient. We report an intraoperative technique that combines laparoscopic with endoscopic methods to determine the position of the gastroesophageal junction. Because two physicians are required, there is additional operating room time, resulting in increased costs. However, these costs are offset by the assurance that the complications of the short esophagus can be avoided. With experience, modifications were made, resulting in the technique described herein.
Esophageal shortening is a known complication of advanced gastroesophageal reflux disease that ma... more Esophageal shortening is a known complication of advanced gastroesophageal reflux disease that may preclude a tension-free antireflux procedure. A retrospective analysis was performed to test the accuracy of preoperative testing. From September 1993 to December 1998, 39 patients underwent esophageal mobilization with intraoperative length assessment. Patients were selected on the basis of irreducible hiatal hernia, stricture formation, or both. Patients in the upright position with a fixed hiatal hernia larger than 5 cm on an esophagram were considered to have a short esophagus. Manometric length two standard deviations below the mean for height was considered abnormally short. In 31 patients, intraoperative mobilization was sufficient to allow the gastroesophageal junction to lie 2 cm below the diaphragmatic crus, so no esophageal-lengthening procedure was required. Eight patients with a short esophagus required an esophageal-lengthening procedure after complete mobilization. Two patients subsequently underwent intrathoracic migration of the gastroesophageal junction (GEJ), with recurrence of symptoms and required gastroplasty during the second surgery. An esophagram had a sensitivity of 66% and a positive predictive value of 37%, whereas manometric length had a sensitivity of 43% and a positive predictive value of 25% for the diagnosis of short esophagus. The preoperative endoscopic finding of either a stricture or Barrett&#39;s esophagus was the most sensitive test for predicting the need for a lengthening procedure. Manometry and esophagraphy are not reliable predictors of the short esophagus. Additional tests and/or tests combined with other parameters are needed.
Small-bowel obstruction secondary to internal hernia is a known postoperative complication of lap... more Small-bowel obstruction secondary to internal hernia is a known postoperative complication of laparoscopic Roux-en-Y gastric bypass (RYGBP). Petersen&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s defect is the most common site of postoperative internal herniation. The authors describe their technique of closure of the infracolic component of the Petersen&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;s defect using continuous non-absorbable suture material. The method has been used successfully to reduce the incidence of internal herniation after laparoscopic RYGBP.
... Composites Science and Technology 69(7-8):1101-7. Paya, I., Yepes, V., Gonzalez-Vidosa, F. &a... more ... Composites Science and Technology 69(7-8):1101-7. Paya, I., Yepes, V., Gonzalez-Vidosa, F. &amp; Hospitaler, A. 2008. Multiobjective optimization of concrete frames by simulated annealing. Computer-Aided Civil and Infrastruc-ture Engineering 23(8):596-610. ...
... Furthermore, applied fire effect after applying the external load to the structure is an ... ... more ... Furthermore, applied fire effect after applying the external load to the structure is an ... Finally, thecreep and shrinkage strain might be considered in the future studies ... Finite Element Analysis of Fibre Reinforce Concrete Beam Subject to High Temperature by Using EURO-Code ...
JSLS : Journal of the Society of Laparoendoscopic Surgeons / Society of Laparoendoscopic Surgeons
Laparoscopic fundoplication has revolutionized the surgical treatment of gastroesophageal reflux ... more Laparoscopic fundoplication has revolutionized the surgical treatment of gastroesophageal reflux disease. Despite improvements in the technique of fundoplication, persistent dysphagia remains a significant cause of postoperative morbidity. Causes of persistent postoperative dysphagia were analyzed in a consecutive series of 167 patients after laparoscopic Nissen fundoplication. Short gastric vessel division and its effect on postoperative dysphagia were analyzed. Follow-up was possible in 139 patients (83%). The mean follow-up period was 27 +/- 21 months. Nine patients (6%) had persistent (moderate to severe) dysphagia, and 33 patients (24%) had mild dysphagia. The satisfaction score among patients with persistent dysphagia was significantly lower than that in patients with mild dysphagia (P < 0.0002). On the other hand, the satisfaction rate among patients with mild dysphagia and those who are asymptomatic was similar. Manometry, performed in 7 of 9 persistent dysphagia patients...
Large bowel obstruction with perforation is an anomalous presentation of pancreatic tail carcinom... more Large bowel obstruction with perforation is an anomalous presentation of pancreatic tail carcinoma. Pancreatic cancer is often difficult to diagnose clinically and is especially furtive when it is located in the tail of the pancreas. We describe a patient who presented with large bowel obstruction due to splenic flexure mass which proved to be due to pancreatic mucinous adenocarcinoma. Pancreatic adenocarcinoma can rarely have the same presentation as colon cancer, and should therefore be considered in the differential diagnosis of large bowel obstruction.
Postoperative pain after laparoscopic cholecystectomy (LC) is generally less than open cholecyste... more Postoperative pain after laparoscopic cholecystectomy (LC) is generally less than open cholecystectomy; however, the postoperative shoulder and abdominal pain experienced by patients still causes preventable distress. Intraperitoneal irrigation of the diaphragmatic surface and gallbladder fossa using normal saline, bupivacaine, or lignocaine may effectively control visceral abdominal pain after an LC. Two hundred patients with similar demographics undergoing elective LC were randomized to one of four groups of 50 patients each, including Group A placebo control, Group B with isotonic saline irrigation, Group C with bupivacaine irrigation, and Group D with lignocaine irrigation. All patients received preperitoneal abdominal wall infiltration with 0.25 per cent bupivacaine to control parietal (somatic) abdominal pain. The visual analogue and verbal rating pain scores at 0, 4, 8, 12 and 24 hours for both shoulder and abdominal pain were recorded in a prospective double-blind fashion at four points during the first 24 postoperative hours. Analgesia requirements, vital signs, blood glucose, and incidence of nausea and vomiting were also recorded. Patients in each group demonstrated a significant difference in visual analogue and verbal rating pain scores and analgesic consumption when compared with controls. Lignocaine controlled pain significantly better than saline or bupivacaine. Bowel function recovery was similar in all patients, and there were no significant complications. We conclude that intraperitoneal irrigation with either saline, bupivacaine, or lignocaine can significantly reduce visceral abdominal pain after LC. Lignocaine was the most efficacious local anesthetic in this trial and has a high safety profile when used at recommended doses.
... In addition, its use has been increasing for the repairing, strengthening and replacement of ... more ... In addition, its use has been increasing for the repairing, strengthening and replacement of old structures. ... Applied Soft Computing. ... [65] Ghiasi H, Fayazbakhsh K, Pasini D, Lessard L. Optimum stacking sequence design of composite materials Part II: Variable stiffness design. ...
With successful surgical treatment of gastroesophageal reflux disease (GERD), there is interest i... more With successful surgical treatment of gastroesophageal reflux disease (GERD), there is interest in understanding the anti-reflux barrier and its mechanisms of failure. To date, the potential use of vector volumes to predict the DeMeester score has not been adequately explored. 627 patients in the referral database received esophageal manometry and ambulatory 24-hour pH monitoring. Study data included LES resting pressure (LESP), overall LES length (OL) and abdominal length (AL), total vector volume (TVV) and intrabdominal vector volume (IVV). In cases where LESP, TVV or IVV were all below normal, there was an 81.4 % probability of a positive DeMeester score. In cases where all three were normal, there was an 86.9 % probability that the DeMeester score would be negative. Receiver-operating characteristics (ROC) for LESP, TVV and IVV were nearly identical and indicated no useful cut-off values. Logistic regression demonstrated that LESP and IVV had the strongest association with a pos...
To determine predictive factors for postoperative dysphagia after laparoscopic myotomy for achala... more To determine predictive factors for postoperative dysphagia after laparoscopic myotomy for achalasia. Logistic regression was used to investigate the possible association between the response (postoperative dysphagia, with two levels: none/mild and moderate/severe) and several plausible predictive factors. Eight patients experienced severe or moderate postoperative dysphagia. The logistic regression revealed that only the severity of preoperative dysphagia (with four levels: mild, moderate, severe, and liquid) was a marginally significant (P=0.0575) predictive factor for postoperative dysphagia. The severity of postoperative dysphagia is strongly associated with preoperative dysphagia. Preoperative symptomatology can significantly impact patient outcome.
Background: Self-expanding metal and plastic esophageal stents (SEMS and SEPS, respectively) are ... more Background: Self-expanding metal and plastic esophageal stents (SEMS and SEPS, respectively) are used in conjunction with chemoradiation for palliation of malignant dysphagia. To date, the dosimetric effects of stents undergoing proton radiotherapy are not known. Study aim: To investigate the proton radiotherapy dose perturbations caused by esophageal stents of varying designs and materials undergoing external beam treatment for esophageal cancer. Patients and methods: Simulated clinical protocol. Solid acrylic phantom was used to mimic the esophageal tissue environment. Stents made of nitinol, stainless steel and polyester were tested. Proton beam dose of 2 Gy-E was delivered to each stent in a single anterior to posterior field. Film and image based evidence of dose perturbation were main outcomes measured. Results: Only the stainless steel and plastic stents demonstrated slight overall dose attenuations (- 0.5 % and - 0.4 %, respectively). All the nitinol-based stents demonstrated minimal overall dose perturbations ranging from 0.0 % to 1.2 %. Negligible dose perturbations were observed on each of the stent surfaces proximal to the radiation source, ranging from - 0.8 % (stainless steel stent) to 1.0 % (nitinol stent). Negligible dose effects were also observed on the distal surfaces of each stent ranging from - 0.5 % (plastic and stainless steel stents) to 1.0 % (nitinol stent). Conclusion: Proton radiotherapy dose perturbations caused by stents of varying designs and material composition are negligible. Negligible dose perturbation is in keeping with the inherent advantage of proton therapy over traditional radiotherapy composed of photons - given its relative large mass, protons have little side scatter.
As antireflux surgery has been used increasingly for gastroesophageal reflux disease (GERD), a ne... more As antireflux surgery has been used increasingly for gastroesophageal reflux disease (GERD), a need has arisen for an accurate method to assess esophageal length. There are a number of preoperative tests that can help surgeons to establish the presence of a short esophagus, but intraoperative assessment after esophageal mobilization is the standard method. In this era of laparoscopic surgery, the surgeon mobilizes the esophagus extensively from the abdomen and then determines if mobilization is sufficient. We report an intraoperative technique that combines laparoscopic with endoscopic methods to determine the position of the gastroesophageal junction. Because two physicians are required, there is additional operating room time, resulting in increased costs. However, these costs are offset by the assurance that the complications of the short esophagus can be avoided. With experience, modifications were made, resulting in the technique described herein.
Esophageal shortening is a known complication of advanced gastroesophageal reflux disease that ma... more Esophageal shortening is a known complication of advanced gastroesophageal reflux disease that may preclude a tension-free antireflux procedure. A retrospective analysis was performed to test the accuracy of preoperative testing. From September 1993 to December 1998, 39 patients underwent esophageal mobilization with intraoperative length assessment. Patients were selected on the basis of irreducible hiatal hernia, stricture formation, or both. Patients in the upright position with a fixed hiatal hernia larger than 5 cm on an esophagram were considered to have a short esophagus. Manometric length two standard deviations below the mean for height was considered abnormally short. In 31 patients, intraoperative mobilization was sufficient to allow the gastroesophageal junction to lie 2 cm below the diaphragmatic crus, so no esophageal-lengthening procedure was required. Eight patients with a short esophagus required an esophageal-lengthening procedure after complete mobilization. Two patients subsequently underwent intrathoracic migration of the gastroesophageal junction (GEJ), with recurrence of symptoms and required gastroplasty during the second surgery. An esophagram had a sensitivity of 66% and a positive predictive value of 37%, whereas manometric length had a sensitivity of 43% and a positive predictive value of 25% for the diagnosis of short esophagus. The preoperative endoscopic finding of either a stricture or Barrett&#39;s esophagus was the most sensitive test for predicting the need for a lengthening procedure. Manometry and esophagraphy are not reliable predictors of the short esophagus. Additional tests and/or tests combined with other parameters are needed.
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