Clinical Focus

  • Pediatric Surgery
  • Surgical Procedures, Minimally Invasive
  • Endoscopic Gastrointestinal Surgery

Academic Appointments

Professional Education

  • Board Certification: Pediatric Surgery, American Board of Surgery (2015)
  • Fellowship:Stanford University School of Medicine (2003) CA
  • Residency:UCSF - Dept of Surgery (2003) CA
  • Internship:UCSF - Dept of Surgery (2003) CA
  • Medical Education:University of Pennsylvania (2003) PA
  • Board Certification: General Surgery, American Board of Surgery (2010)


2015-16 Courses

Graduate and Fellowship Programs

  • Pediatric Surgery (Fellowship Program)


All Publications

  • A Prospective Randomized Trial of Ultrasound- vs Landmark-Guided Central Venous Access in the Pediatric Population JOURNAL OF THE AMERICAN COLLEGE OF SURGEONS Bruzoni, M., Slater, B. J., Wall, J., St Peter, S. D., Dutta, S. 2013; 216 (5): 939-943


    The purpose of this prospective randomized study was to compare landmark- to ultrasound-guided central venous access when performed by pediatric surgeons. The American College of Surgeons advocates for use of ultrasound in central venous catheter placement; however, this is not universally embraced by pediatric surgeons. Complication risk correlates positively with number of venous cannulation attempts.With IRB approval, a randomized prospective study of children under 18 years of age undergoing tunneled central venous catheter placement was performed. Patient accrual was based on power analysis. Exclusion criteria included known nonpatency of a central vein or coagulopathy. After randomization, the patients were assigned to either ultrasound-guided internal jugular vein access or landmark-guided subclavian/internal jugular vein access. The primary outcomes measure was number of attempts at venous cannulation. Secondary outcomes measures included: access times, number of arterial punctures, and other complications. Continuous variables were compared using 2-tailed Student's t-test. Discrete variables were analyzed with chi-square. Significance was defined as p < 0.05.There were 150 patients enrolled between April 2008 and September 2011. There was no difference when comparing demographic data. Success at first attempt was achieved in 65% of patients in the ultrasound group vs 45% in the landmark group (p = 0.021). Success within 3 attempts was achieved in 95% of ultrasound group vs 74% of landmark group (p = 0.0001).Ultrasound reduced the number of cannulation attempts necessary for venous access. This indicates a potential to reduce complications when ultrasound is used by pediatric surgeons.

    View details for DOI 10.1016/j.jamcollsurg.2013.01.054

    View details for Web of Science ID 000318680500013

  • Complete resection of a rare intrahepatic variant of a choledochal cyst JOURNAL OF PEDIATRIC SURGERY Salles, A., Kastenberg, Z. J., Wall, J. K., Visser, B. C., Bruzoni, M. 2013; 48 (3): 652-654


    The vast majority of choledochal cysts occur as either saccular or diffuse fusiform dilatation of the extrahepatic bile duct. We describe the complete resection of a rare single intrahepatic choledochal cyst communicating with the extrahepatic biliary tree. While previous reports describe partial resection with enteral drainage, we performed a complete resection of this rare choledochal cyst.

    View details for DOI 10.1016/j.jpedsurg.2012.12.016

    View details for Web of Science ID 000316470100037

  • Virtual Neck Exploration for Parathyroid Adenomas A First Step Toward Minimally Invasive Image-Guided Surgery JAMA SURGERY D'Agostino, J., Wall, J., Soler, L., Vix, M., Duh, Q., Marescaux, J. 2013; 148 (3): 232-238


    To evaluate the performance of 3-dimensional (3D) virtual neck exploration (VNE) as a modality for preoperative localization of parathyroid adenomas in primary hyperparathyroidism and assess the feasibility of using augmented reality to guide parathyroidectomy as a step toward minimally invasive imageguided surgery.Enhanced 3D rendering methods can be used to transform computed tomographic scan images into a model for 3D VNE. In addition to a standard imaging modality, 3D VNE was performed in all patients and used to preoperatively plan minimally invasive parathyroidectomy. All preoperative localization studies were analyzed for their sensitivity, specificity, positive predictive value, and negative predictive value for the correct side of the adenoma(s) (lateralization) and the correct quadrant of the neck (localization). The 3D VNE model was used to generate intraoperative augmented reality in 3 cases.Tertiary care center.A total of 114 consecutive patients with primary hyperparathyroidism were included from January 8, 2008, through July 26, 2011.The accuracy of 3D VNE in lateralization and localization was 77.2% and 64.9%, respectively. Virtual neck exploration had superior sensitivity to ultrasonography (P.001), sestamibi scanning (P=.07), and standard computed tomography (P.001). Use of the 3D model for intraoperative augmented reality was feasible.3-Dimensional VNE is an excellent tool in preoperative localization of parathyroid adenomas with sensitivity, specificity, and diagnostic accuracy commensurate with accepted first-line imaging modalities. The added value of 3D VNE includes enhanced preoperative planning and intraoperative augmented reality to enable less-invasive image-guided surgery.

    View details for DOI 10.1001/jamasurg.2013.739

    View details for Web of Science ID 000316682000005

    View details for PubMedID 23682370

  • Successful extracorporeal membrane oxygenation treatment for pheochromocytoma-induced acute cardiac failure AMERICAN JOURNAL OF EMERGENCY MEDICINE Sojod, G., Diana, M., Wall, J., D'Agostino, J., Mutter, D., Marescaux, J. 2012; 30 (6)


    The aim of this study is to report the case of a catecholamine-induced cardiogenic shock bridged to curative adrenalectomy using extracorporeal membrane oxygenation (ECMO) and medical management. A 37-year-old woman presented an acute cardiogenic shock due to a left-sided pheochromocytoma. Echocardiography revealed a severe global hypokinesia with a left ventricular ejection fraction of 15%. Despite maximal ionotropic support, adequate perfusion could not be achieved; and ECMO was used to bridge the patient during medical management with calcium-channel blockers. The left ventricular ejection fraction improved to 65%, and ECMO was discontinued after 11 days. An open left adrenalectomy was performed 10 days after ECMO. At 1-year follow-up, the patient is in good health with normal cardiac function. Pheochromocytomas can present with dramatic cardiovascular collapse. With timely diagnosis and medical therapy, followed by surgical resection, the cardiovascular effects can be reversed; and the condition, cured. Young patients with catecholamine-induced cardiac failure refractory to medical therapy are ideal candidates for short-term ECMO support, as the underlying cause is imminently reversible.

    View details for DOI 10.1016/j.ajem.2011.05.006

    View details for Web of Science ID 000305811600046

    View details for PubMedID 21741786

  • An Original Endoluminal Magnetic Anastomotic Device Allowing Pure NOTES Transgastric and Transrectal Sigmoidectomy in a Porcine Model: Proof of Concept SURGICAL INNOVATION Leroy, J., Perretta, S., Diana, M., Wall, J., Lindner, V., Harrison, M., Marescaux, J. 2012; 19 (2): 109-116


    While experimental natural orifice transluminal endoscopic surgery (NOTES) sigmoid colectomies have been reported, pure NOTES anastomoses are restricted by the limited reach of commercially available circular staplers. MAGNAMOSIS is a set of self-orienting magnetic rings that can be delivered endoluminally throughout the colon to generate a compression anastomosis. Aim. To assess the feasibility of a pure NOTES transrectal (TR) and transgastric (TG) approach to perform any segmental colectomy.One pig (50 kg) underwent the experimental procedure as follows: (a) creation of the TG access to the peritoneal cavity, (b) precise transluminal placement of the proximal MAGNAMOSIS ring, (c) creation of the TR access with the TEO and transrectal dissection of the sigmoid mesentery, (d) resection of the surgical specimen, (e) transrectal extraction of the specimen, (f) delivery and mating of the distal MAGNAMOSIS ring, and (g) closure of the TG and TR viscerotomies. The animal survived for 14 days at which time burst pressure and histology were performed.A pure NOTES TR and TG segmental colectomy was performed in 139 minutes. The postoperative course was uneventful. The animal had a formed bowel movement including the magnetic rings on postoperative day 5. Endoscopic examination at postoperative day 14 revealed a patent anastomosis. Necropsy revealed no abscess or signs of peritonitis. Burst pressure was >198 mm Hg. The histology showed a sealed anastomosis with mild inflammation.MAGNAMOSIS enabled a totally NOTES partial colectomy with combined TG and TR access. The flexible delivery options and low cost of manufacturing could make MAGNAMOSIS an attractive alternative to circular staplers.

    View details for DOI 10.1177/1553350611429029

    View details for Web of Science ID 000304822100001

    View details for PubMedID 22143749

  • Prospective evaluation of peritoneal fluid contamination following transabdominal vs. transanal specimen extraction in laparoscopic left-sided colorectal resections SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES Costantino, F. A., Diana, M., Wall, J., Leroy, J., Mutter, D., Marescaux, J. 2012; 26 (6): 1495-1500


    Natural orifice specimen extraction (NOSE) in colorectal surgery prevents the need for an enlarged port site or minilaparotomy to extract the surgical specimen. The downside of this technique may be an increased risk of bacterial contamination of the peritoneal cavity from the external milieu. The aim of this study was to prospectively analyze the peritoneal bacterial contamination in NOSE and non-NOSE laparoscopic colorectal procedures.Consecutive patients operated for sigmoid diverticulitis with laparoscopic approach and transanal extraction of the specimen from January to December 2010 at our university hospital were enrolled. Patients who underwent a laparoscopic sigmoidectomy in the same study period with conventional specimen extraction were used as reference. Peritoneal fluid samples were collected under sterile conditions at the end of the procedure and sent for gram stain as well as anaerobic, aerobic, and fungal cultures.Twenty-nine patients underwent laparoscopic sigmoidectomy for diverticulitis with transanal NOSE, while 9 patients underwent laparoscopic sigmoidectomy with conventional specimen extraction during the same period. The two groups were successfully matched 1:2 (17 NOSE and 9 non-NOSE) according age, sex, ASA, and Charlson comorbidity score. The contamination rate of peritoneal fluid was 100% vs. 88.9% in NOSE and non-NOSE procedures, respectively (P = 0.23). Overall and major complications rates were 27.6% vs. 11.10% (P = 0.41) and 5.08% vs. 11.1% (P = 1) in NOSE vs. non-NOSE procedures, respectively. In the NOSE group there was a statistically significant lower consumption of oral paracetamol (P = 0.007) and of oral tramadol (P = 0.02).Although a higher peritoneal contamination was found in the NOSE procedures, there were no significant differences in clinical outcomes relative to standard approach. Avoiding a minilaparotomy to extract the specimen resulted in a significantly lower postoperative analgesic requirement in the NOSE group.

    View details for DOI 10.1007/s00464-011-2066-6

    View details for Web of Science ID 000304161500001

    View details for PubMedID 22179455

  • Submucosal Endoscopic Myotomies for Esophageal Lengthening: A Novel Minimally Invasive Technique with Feasibility Study EUROPEAN JOURNAL OF PEDIATRIC SURGERY Wall, J., Perretta, S., Diana, M., Dhumane, P., Haro, J. A., Dallemagne, B., Becmeur, F., Krummel, T., Marescaux, J. 2012; 22 (3): 217-221


    Replacement conduits carry significant morbidity in long gap esophageal atresia. Surgical myotomies can lengthen the esophagus, but have not gained widespread adoption due to long-term dilatation. The aim of this study is to assess the feasibility of an emerging minimally invasive technique of submucosal endoscopic myotomy for esophageal lengthening.Bilateral submucosal lengthening endoscopic myotomies (BSLEM) were performed in three swine. Circular esophageal muscle fibers were selectively divided in a bilateral 3 cm longitudinal pattern. Ex-vivo tensile testing was performed on the BSLEM and compared with three circular myotomies, three spiral myotomies, and three controls.BSLEM was completed in all cases with one esophageal microperforation. The mean operating time was 38 minutes. Over physiologic force ranges of 0 to 100 g, the percentage esophageal elongation was significantly different among the four groups (p<0.05). Spiral myotomy enabled the maximal lengthening among the techniques. BSLEM enabled lengthening significantly greater than controls, but less than both types of surgical myotomy.BSELM is feasible and allows significant esophageal lengthening. Unlike surgical myotomies, BSELM enables selective division of circular fibers to potentially preserve perfusion near the anastomosis and prevent long-term dilatation. Studies are ongoing to characterize the ideal pattern of selective endoscopic myotomy and long-term effects.

    View details for DOI 10.1055/s-0032-1308711

    View details for Web of Science ID 000306110600008

    View details for PubMedID 22576306

  • Totally Endoscopic Magnetic Enteral Bypass by External Guided Rendez-Vous Technique SURGICAL INNOVATION Diana, M., Wall, J., Perretta, S., Dallemagne, B., Gonzales, K. D., Harrison, M. R., Agnus, V., Soler, L., Nicolau, S., Marescaux, J. 2011; 18 (4): 317-320


    This study aimed to assess the feasibility of a totally endoscopic enteral bypass using a self-orienting, dual ring, magnetic anastomosis system (MAGNAMOSIS) guided by a magnetic tracking system (3D METRIS).In an anesthetized pig, 2 endoscopes were advanced, one each into the stomach and the colon. Both endoscopes were equipped with a MAGNAMOSIS ring secured with an endoscopic snare and a 3D METRIS within one working channel. The whole procedure was followed laparoscopically. The tracking system guided tips of endoscopes to a "rendez-vous" location between the colon and stomach.MAGNAMOSIS magnets automatically joined in the correct configuration when guided to within 2 cm of each other. At necropsy, magnetic rings were secure without entrapment of excess bowel or mesentery.An endoscopic enteral bypass with magnetic anastomosis and magnetic tracking device was feasible. More accurate tracking and advanced techniques could enable endoscopic bypasses at multiple sites in the gastrointestinal tract.

    View details for DOI 10.1177/1553350611409761

    View details for Web of Science ID 000299896100004

    View details for PubMedID 21742664

  • Two novel endoscopic esophageal lengthening and reconstruction techniques SURGICAL ENDOSCOPY AND OTHER INTERVENTIONAL TECHNIQUES Perretta, S., Wall, J. K., Dallemagne, B., Harrison, M., Becmeur, F., Marescaux, J. 2011; 25 (10): 3440-3440


    Esophageal reconstruction presents a significant clinical challenge in patients ranging from neonates with long-gap esophageal atresia to adults after esophageal resection. Both gastric and colonic replacement conduits carry significant morbidity. As emerging organ-sparring techniques become established for early stage esophageal tumors, less morbid reconstruction techniques are warranted. We present two novel endoscopic approaches for esophageal lengthening and reconstruction in a porcine model.Two models of esophageal defects were created in pigs (30-35 kg) under general anesthesia and subsequently reconstructed with the novel techniques. The first model was a segmental defect of the esophagus created by thoracoscopically transecting the esophagus above the gastroesophageal (GE) junction. The first reconstruction technique involved bilateral submucosal endoscopic lengthening myotomies (BSELM) with a magnetic compression anastomosis (MAGNAMOSIS™). The second model was a wedge defect in the anterior esophagus created above the GE junction through a laparotomy. The second reconstruction technique involved an inverted mucosal-submucosal sleeve transposition graft (IMSTG) that crossed the esophageal gap and was secured in place with a self-expandable covered esophageal stent.Both techniques were feasible in the pig model. The BSELM approach lengthened the esophagus 1 cm for every 2 cm length of myotomy. The myotomy targeted only the inner circular fibers of the esophagus, with preservation of the longitudinal layer to protect against long-term dilation and pouching. The IMSTG approach generated a vascularized mucosal graft almost as long as the esophagus itself.Emerging endoscopic capabilities are enabling complex endoluminal esophageal procedures. BSELM and IMSTG are two novel and technically feasible approaches to esophageal lengthening and reconstruction. Further survival studies are needed to establish the safety and efficacy of these techniques.

    View details for DOI 10.1007/s00464-011-1711-4

    View details for Web of Science ID 000294964600048

    View details for PubMedID 21556998

  • Original Technique to Close the Transrectal Viscerotomy Access in a NOTES Transrectal and Transgastric Segmental Colectomy SURGICAL INNOVATION Leroy, J., Diana, M., Perretta, S., Wall, J., De Ruijter, V., Marescaux, J. 2011; 18 (3): 193-200


    Segmental colectomy is an ideal procedure for natural orifice transluminal endoscopic surgery (NOTES). Transanal endoscopic approaches have enabled rectosigmoid colectomy through a viscerotomy that is resected with the specimen. To extend NOTES segmental colectomy to the entire colon and beyond, a rectal viscerotomy will have to be safely and effectively closed at the end of the procedure. A new technique for rectal viscerotomy closure using a circular EEA hemorrhoid and prolapse stapler with DST series technology (Covidien) is described.

    View details for DOI 10.1177/1553350611411490

    View details for Web of Science ID 000297596400004

    View details for PubMedID 21727099

  • Robotic Gastrectomy Is Safe and Feasible, but Real Benefits Remain Elusive ARCHIVES OF SURGERY Wall, J., Marescaux, J. 2011; 146 (9): 1092-1092

    View details for Web of Science ID 000295002900027

    View details for PubMedID 22029074

  • Laparo-Endoscopic Single-Site (LESS) with Transanal Natural Orifice Specimen Extraction (NOSE) Sigmoidectomy: A New Step before Pure Colorectal Natural Orifices Transluminal Endoscopic Surgery (NOTES (R)) JOURNAL OF GASTROINTESTINAL SURGERY Leroy, J., Diana, M., Wall, J., Costantino, F., D'Agostino, J., Marescaux, J. 2011; 15 (8): 1488-1492


    We present the first human case of laparo-endoscopic single-site sigmoidectomy with transanal natural orifice specimen extraction.This technical achievement is a new step toward pure colorectal Natural Orifices Transluminal Endoscopic Surgery. It is the product of a gradual development with critical steps being conceived and standardised in years of experimental and clinical procedures.

    View details for DOI 10.1007/s11605-011-1557-z

    View details for Web of Science ID 000293243200035

    View details for PubMedID 21584823

  • Intellectual property and royalty streams in academic departments: Myths and realities SURGERY Krummel, T. M., Shafi, B. M., Wall, J., Chandra, V., Mery, C., Gertner, M. 2008; 143 (2): 183-191

    View details for DOI 10.1016/j.surg.2007.11.011

    View details for Web of Science ID 000253172300009

    View details for PubMedID 18242333

  • Impact of multiple lymphatic channel drainage to a single nodal basin on outcomes in melanoma ARCHIVES OF SURGERY Wall, J. K., Florero, M., Accortt, N. A., Allen, R., Kashani-Sabet, M., Morita, E., Leong, S. P. 2007; 142 (8): 753-756


    To determine the impact of multiple lymphatic channels (MLCs) on outcome in melanoma.Retrospective cohort study.Academic tertiary care center.Of 1198 consecutive selective sentinel lymphadenectomies performed from 1995 to 2000 for primary invasive melanoma, 502 patients were identified with extremity or truncal melanoma that drained to a single nodal basin. Three cohorts were formed based on lymphatic channels (none, single, and multiple). Tumors with drainage to multiple nodal basins as well as all head and neck tumors were excluded.Multiple variables, including patterns of lymphatic drainage, were analyzed for impact on disease-free and overall survival.Demographics were similar among groups, with a median follow-up of 5.6 years. Univariate analysis revealed MLCs as an independent risk factor for both disease-free (P = .04) and overall survival (P = .003). Multivariate analysis confirmed that tumor depth, sentinel lymph node status, and MLCs were risk factors for both disease-free and overall survival. Kaplan-Meier analysis showed worse survival in the MLCs group.Our study reveals that MLCs are an independent risk factor for recurrence and mortality in melanoma. Multiple lymphatic channels may facilitate the process of metastasis.

    View details for Web of Science ID 000248721200013

    View details for PubMedID 17709729