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SSL introduces ergonomic challenges while establishing the critical view during dissection of the Triangle of Calot (TOC). This study investigates the use of a novel percutaneous instrument platform and MAGS in performing SSL cholecystectomy with a technique that closely mimics four-port cholecystectomy. SSL cholecystectomy was performed on four female cadavers via a 15–18-mm incision made at the umbilicus for introduction of these devices and the working port. MAGS comprises an internal effector with a retractable monopolar cautery hook coupled across the abdominal wall to an external magnet held by the surgeon. The novel grasper was introduced percutaneously in the RUQ and comprises a 3-mm transabdominal shaft mated to a 5-mm end effector intracorporeally. Retraction was accomplished using the percutaneous grasper to manipulate the fundus and a standard 5-mm grasper at the umbilicus for the infundibulum. Dissection was performed by using a combination of the MAGS and a standard Maryland dissector. Total procedure time, time from procedure start to obtain a critical view of the TOC and clipping and dividing the cystic duct/artery, time for dissection of the gallbladder from the liver bed, and thickness of the abdominal wall at the umbilicus were measured. The critical view was obtained in each case, and all four procedures were completed successfully. Mean procedure time was 40 (range, 33–51) min; time from procedure start to obtaining the critical view and clipping and dividing the cystic duct/artery was 33 (range, 28–38) min, and time for dissection of the gallbladder from the liver bed was 6.7 (range, 3–13) min. The mean abdominal wall thickness was 1.9 (range, 1.5–2) cm. The use of a novel graspers and MAGS overcomes the limitations of SSL cholecystectomy and improves surgeon dexterity. Making SSL feel more like traditional laparoscopy will enable a wider adoption of this procedure in the community.

Background: Sigmoid volvulus is an exceptionally rare and potentially life-threatening condition in the pediatric age group. Study Design: We report our experience with three children treated for sigmoid volvulus and review the cases reported in the medical literature since 1940. Results: Since 1940, 63 cases of sigmoid volvulus in children (including this series) have been reported. The median age was 7 years and the male to female ratio was 3.5:1. Two distinct presentations (acute and recurrent) were identified. Abdominal symptoms dominated the clinical picture. Barium enemas either confirmed or were highly suggestive of sigmoid volvulus. Reduction by barium enema was successful in 77% (10 of 13) of the attempts. Forty-nine patients underwent operative treatment, with sigmoidectomy (with or without primary anastomosis) being the most common. The overall mortality rate was 6%, operative mortality was 8.1%, and neonatal mortality was 14%. Associated conditions were frequent. Particular emphasis should be placed on ruling out Hirschsprung's disease (present in 11 of 63 patients). Conclusions: Sigmoid volvulus remains a rare occurrence in children, but it should be included in the differential diagnosis of pain in children when colonic distention is present. An algorithm for treatment is proposed.

Calyceal diverticula are eventrations of the upper collecting system lying within the renal parenchyma and communicating with the main collecting system through small infundibuli. If they are left untreated, stasis of urine can promote infections or stone formation. Traditionally, these diverticuli have been managed with open techniques and more recently with percutaneous or endoscopic techniques. This report describes a modification of the percutaneous technique used successfully in the treatment of a 14-year-old boy in whom a neoinfundibulum was created, dilated, and temporarily stented to provide drainage of the diverticulum.

Minimally invasive components separation (MICS) is believed to decrease wound complications by reducing local tissue damage and eliminating the interruption of blood supply to the overlying skin and soft tissue. One drawback to the MICS technique is the difficulty with identifying the correct location for entry into the anterior abdominal wall. We believe that ultrasound can be used to visually assist identification of the correct surgical entry site (the avascular space between the external and internal abdominal oblique muscles, lateral to the linea semilunaris).The purpose of this study was to assess if novices can readily learn an ultrasound technique for identifying abdominal wall myofascial components via a video education tool.This research was an institutional review board-approved, prospective, observational study. Ten surgical residents were asked to watch a 1-min training video containing basic instructions on ultrasound technique for identifying the myofascial anatomy of the anterior abdominal wall. After watching the educational video, the subjects were asked to identify the linea semilunaris first by external anatomy, then by ultrasound. A grader, blinded to the identification of the subject, recorded if the subject correctly identified the location of the linea semilunaris by each method (external anatomy only versus ultrasound guided).Ten subjects were evaluated. Nine of ten (90 %) subjects correctly identified the linea semilunaris with ultrasound. Only three of ten (30 %) subjects correctly identified the linea semilunaris by physical exam.Ultrasound technology can aid in identification of the abdominal wall musculofascial units in MICS and be easily taught via short video instruction to novices with excellent results. Further studies will be necessary to prove that ultrasound use can decrease complications associated with entry into the appropriate avascular space between the external and internal abdominal oblique muscles, lateral to the linea semilunaris.

Laparoscopic ventral hernia repair using an underlay mesh frequently requires suture fixation across the abdominal wall, which results in significant postoperative pain. This study investigates the utility of a novel mesh fixation technique to reduce the strangulation force on the abdominal wall.Multiple 2-cm(2) pieces of polyester mesh (Parietex Composite, Covidien) were placed as an underlay against a porcine abdominal wall. Fixation was accomplished using either the standard 0-polyglyconate or the 0-polyglyconate barbed anchor suture designed to hold in tissue without the need to tie a knot (V-Loc 180; Covidien). Suture fixation began with a stab wound incision in the skin. A suture-passing device then was used to pass the suture across the abdominal wall and through the mesh. The suture passer was removed and reintroduced through the same stab wound incision but at a different fascial entry point 1.5 cm away. The tail of the suture was grasped and pulled up through both the mesh and the abdominal wall, creating a full-thickness U-stitch. One tail of the suture was attached to a tensiometer, and the strangulation force on the abdominal wall was measured while the suture was tied (standard) or looped (barbed). To compare pullout force, the tensiometer was attached to either the mesh or the suture, and traction was applied until material failure or suture pull through. Results are expressed as mean ± standard deviation. Comparisons were performed using Student's t-test.Eight pieces of mesh were placed for each suture. The average force required to secure the barbed suture (0.59 ± 0.08 kg) was significantly less than the force needed to secure the standard suture (2.17 ± 0.58 kg) (P0.0001). Table 1 compares the suture pullout forces with the mesh failure forces. Although the pullout force for the standard suture is significantly greater than for the barbed suture, both sutures have a pullout strength significantly greater than the mesh failure force. Table 1 Suture fixation forces for standard and barbed sutures Suture fixation force (kg) Standard suture 2.17 ± 0.58 Barbed suture 0.59 ± 0.08 P0.0001A barbed anchor suture used to secure mesh to the abdominal wall requires nearly 75% less strangulation force than a standard monofilament suture while still providing significantly greater pullout force than that required for the mesh to tear and fail. This method of mesh fixation should result in less postoperative pain and warrants a clinical trial.

Single-incision laparoscopic surgery (SILS) is limited by the coaxial arrangement of the instruments. A surgical robot with wristed instruments could overcome this limitation, but the arms often collide when working coaxially. This study tests a new technique of "chopstick" surgery to enable use of the robotic arms through a single incision without collision.Experiments were conducted utilizing the da Vinci S robot (Intuitive Surgical, Inc., Sunnyvale, CA) in a Fundamentals of Laparoscopic Surgery (FLS) box trainer with three laparoscopic ports (1 x 12 mm, 2 x 5 mm) introduced through a single "incision." Pilot work determined the optimal setup for SILS to be a triangular port arrangement with 2-cm trocar distance and remote center at the abdominal wall. Using this setup, five experienced robotic surgeons performed three FLS tasks utilizing either a standard robotic arm setup or the chopstick technique. The chopstick arrangement crosses the instruments at the abdominal wall so that the right instrument is on the left side of the target and the left instrument on the right. This results in separation of the robotic arms outside the box. To correct for the change in handedness, the robotic console is instructed to drive the "left" instrument with the right-hand effector and the "right" instrument with the left. Performances were compared while measuring time, errors, number of clutching maneuvers, and degree of instrument collision (Likert scale 1-4).Compared with the standard setup, the chopstick configuration increased surgeon dexterity and global performance through significantly improved performance times, eliminating instrument collision, and decreasing number of camera manipulations, clutching maneuvers, and errors during all tasks.Chopstick surgery significantly enhances the functionality of the surgical robot when working through a small single incision. This technique will enable surgeons to utilize the robot for SILS and possibly for intraluminal or transluminal surgery.

Introduction Single-incision laparoscopic surgery (SILS) is limited by the coaxial arrangement of the instruments. A surgical robot with ‘‘wristed’’ instruments could overcome this limitation but the ‘‘arms’’ collide when working coaxially. This video demonstrates a new technique of ‘‘chopstick surgery,’’ which enables use of the robotic arms through a single incision without collision. Methods Experiments were conducted utilizing the da Vinci S robot (Sunnyvale, CA) in a porcine model with three laparoscopic ports (12 mm, 2–5 mm) introduced through a single ‘‘incision.’’ Pilot work conducted while performing Fundamentals of Laparoscopic Surgery (FLS) tasks determined the optimal setup for SILS to be a triangular port arrangement with 2-cm trocar distance and remote center at the abdominal wall. Using this setup, an experienced robotic surgeon performed a cholecystectomy and nephrectomy in a porcine model utilizing the ‘‘chopstick’’ technique. The chopstick arrangement crosses the instruments at the abdominal wall so that the right instrument is on the left side of the target and the left instrument on the right. This arrangement prevents collision of the external robotic arms. To correct for the change in handedness, the robotic console is instructed to drive the ‘‘left’’ instrument with the right hand effector and the ‘‘right’’ instrument with the left. Results Both procedures were satisfactorily completed with no external collision of the robotic arms, in acceptable times and with no technical complications. This is consistent with results obtained in the box trainer where the chopstick configuration enabled significantly improved times in all tasks and decreased number of errors and eliminated instrument collisions. Conclusion Chopstick surgery significantly enhances the functionality of the surgical robot when working through a small single incision. This technique will enable surgeons to utilize the robot for SILS and possibly for intraluminal or transluminal surgery.

We tested the hypothesis that in spontaneously hypertensive rat (SHR) NO produced centrally influences the resting arterial blood pressure by attenuating mechanisms involving prostaglandins, angiotensin II, endothelin and sympathetic nervous system. L-NAME (200 micro g/5 micro l), an inhibitor of NO synthase, administered intracerebroventricularly (i.c.v.) to awake and freely moving rats increased mean arterial blood pressure (MABP) in a biphasic pattern: an early transient increase within 1 min and a late prolonged response starting at 45 min and persisting for the duration of experiment (180 min). The two pressor responses involve different neurochemical mechanisms and, based on their latencies, they appear to reflect different anatomical sites of action of L-NAME. The late, but not the early pressor response, was prevented by pretreatment with chlorisondamine (2.5 mg/kg, i.v.), a ganglionic blocker, indicating its dependence on the sympathetic nervous system. Both pressor responses were abolished by i.c.v. pretreatment with indomethacin (200 micro g/5 micro l, i.c.v.), an inhibitor of cyclo-oxygenase, showing that they are mediated by prostaglandin(s). In contrast, losartan (25 micro g/5 micro l), an angiotensin II AT(1) receptor antagonist, had no effect. The initial pressor response was also attenuated by pretreatment with the endothelin ET(A)/ET(B) receptor antagonist, PD 145065 (48 micro g/2 micro l, i.c.v.). Intravenous pretreatment with another ET(A)/ET(B) receptor antagonist, L-754,142 (15 mg/kg as a bolus+15 mg/kg/h for 180 min), however, attenuated both responses to L-NAME. It is possible that L-754,142 crossed the blood-brain barrier and blocked, in addition, central ET(A)/ET(B) receptors. These studies show that NO synthesized in the brain attenuates pressor mechanisms involving prostaglandin, endothelin and sympathetic nervous system, but not angiotensin II, to modulate resting arterial blood pressure.

Our objective was to test the hypothesis that the cGMP signal-transduction mechanism mediates nitric oxide's (NO) modulation of oxytocin (OT) and vasopressin (VP) secretion from the hypothalamo-neurohypophysial system. Three studies were conducted in adult male Sprague-Dawley rats: (1a) Euhydrated rats received an intracerebroventricular (icv) infusion (1 microl/min for 30 min) of artificial cerebrospinal fluid (aCSF), vehicle (2.6% dimethyl sulfoxide [DMSO]) or 1H-[1,2,4]oxadiazolo-[4,3-a]quinoxalin-1-one (ODQ) (0.05 microg/microl), an inhibitor of soluble guanylyl cyclase (sGC). ODQ did not affect basal levels of plasma VP or OT; (1b) Rats dehydrated for 24 h received aCSF or 8-Br-cGMP (icv), a membrane-permeable analog of cGMP, and plasma hormones were measured 2 min later. 8-Br-cGMP did not significantly change VP or OT levels; (2) Rats ingested water or 2% NaCl for 4 days, and NO synthase (NOS) and sGC activities were measured in posterior pituitaries, the anatomical site of hormone secretion. Salt loading enhanced (P0.001) production of [(14)C]citrulline, the coproduct of NO synthesis, without altering cGMP; (3) One SON was microdialyzed with [(14)C]arginine and NOS and sGC activities were quantified in microdialysates during intravenous (iv) infusion of isotonic or hypertonic saline in awake and anesthetized rats. In awake rats, [(14)C]citrulline recovery, but not cGMP, increased (P0.05) during intravenous infusion of both isotonic and hypertonic solutions, and after insertion of microdialysis probe itself. In anesthetized rats, however, where basal NOS activity is low, intravenous infusion of hypertonic, but not isotonic solution, increased [(14)C]citrulline recovery without affecting cGMP. Thus, in the forebrain, neither NO produced basally nor during osmotic stimulation depends on cGMP to modulate plasma vasopressin and oxytocin secretion.

The stem cell spheroids were infected with NV1066, a third-generation herpesvirus, or NDV-F3aa-GFP, a Newcastle Disease virus mutant. Both viruses carried the marker gene green fluorescent protein (GFP), which allowed monitoring by fluorescent microscopy. Cell cycle analysis and cell migration assay were also performed. Results: Viral infection of cancer stem cells was rapid (GFP expression was seen by 24 hours). The viruses from both families each produced efficient infection and killing of cancer. At doses of multiplicity of infection (MOI, number of viruses per tumor cell) of 0.5 or 1, >95% of cells were dead by day 6. Infection with virus also produced decreased migratory capacity of the cancer stem cells and shifted the population to a higher fraction in S phase. Conclusion: Multiple types of oncolytic viruses effectively target the stem cell subpopulation of pancreatic cancer cells. Infection decreases metastatic potential and effects killing of such stem cells. These data support clinical studies of oncolytic viruses in the treatment of chemoand radioresistant tumors.