Our Faculty

Vikram Reddy, MD, PhD, MBA is chief of Colon and Rectal Surgery at Yale School of Medicine. He is a fellowship-trained colon and rectal surgeon. His goal is to help individuals have managed relief from chronic inflammatory bowel disease and its painful symptoms. He has extensive experience in the laparoscopic and robotic management and screening of anorectal cancer. He specializes in advanced laparoscopic management of colon and rectal diseases; screening and laparoscopic management of colon cancer; screening and management of rectal cancer (including laparoscopic or robotic sphincter preserving surgery and Transanal Endoscopic Microsurgery (TEMS); laparoscopic and robotic management of complicated or uncomplicated diverticulitis; management of inflammatory bowel disease (including laparoscopic bowel resection and ostomy, laparoscopic or robotic proctocolectomy, and J-pouch for ulcerative colitis); laparoscopic or robotic management of polyposis syndromes and disorders of continence.

Dr. Maija Cheung is an Assistant Professor in Surgery in the Division of Bariatrics and Minimally Invasive Surgery.  Dr. Cheung also serves as the Associate Program Director for Clinical Skills for the General Surgery Program and Associate Program Director for the Bariatric and Minimally Invasive Surgery Fellowship Program. Her clinical interests are in hernia, foregut and bariatric surgery and integrating robotics into this practice.Dr. Cheung completed her General Surgery Residency at Yale New Haven Hospital and was the first Yale Global Surgery Research Fellow.  Her research focused on capacity building and educational projects in pediatric surgery and trauma and emergency general surgery in Uganda. She has worked with a philanthropic organization, KidsOR since 2017 as an International Advisory Board member helping steer clinical development opportunities and data collection policies and in 2021 was appointed as their Global Lead for Surgery.Dr. Cheung completed her fellowship in Bariatrics and Minimally Invasive Surgery at Yale.  Her current research is focused on global trauma and surgical outcomes, developing education, simulation, and training programs both in the United States and in low income countries, and building reciprocal clinical and research collaborations between international institutions.

Andrew J. Duffy, MD, FACS, FASMBS is a Board Certified General Surgeon and is fellowship-trained in minimal access surgery. He is the Associate Surgical Chief of the Digestive Health Service line and the Medical Director of the Hernia Center for Yale-New Haven Health System. He has additional subspecialty certification through the American Board of Surgery in Metabolic and Bariatric Surgery. He offers minimally invasive surgery of the abdomen and GI tract, including laparoscopic and robotic techniques. Dr. Duffy has a long history in surgical education. He has developed simulator programs and utilized other technology to help develop the Yale surgical residents and fellows into top Minimally Invasive and Robotic Surgeons He is currently the interim Program Director for the General Surgery Residency Program at Yale His clinical goal is to offer the most effective surgery with the least recovery time and post-operative discomfort. Dr. Duffy is dedicated to helping individuals with acute and chronic issues related to hernias or with their stomach, intestines, gallbladder, or other abdominal organs. He specializes in all type of primary and recurrent abdominal wall. He has extensive experience at surgically treating hernia surgery-related complications, including mesh problems. He also offers minimally invasive techniques for correcting hiatal hernias, GERD, acid reflux, paraesophageal hernias, complications of prior stomach and hiatal hernia surgery, achalasia and other swallowing disorders. He also specializes in laparoscopic and robotic procedures for obesity, including gastric bypass, sleeve gastrectomy, adjustable gastric banding and revision of prior bariatric surgery. He specializes in laparoscopic gastrointestinal surgery; laparoscopic bariatric surgery for morbid obesity; laparoscopic gastric bypass surgery; laparoscopic adjustable gastric banding; laparoscopic sleeve gastrectomy; revisional bariatric surgery; laparoscopic surgery for reflux and achalasia; laparoscopic Nissen, laparoscopic Heller myotomy; laparoscopic splenectomy; laparoscopic paraesophageal hernia repair; laparoscopic repair of abdominal-wall hernias; laparoscopic repair of inguinal hernias; gall bladder; gall stones; cholecystectomy; gall stone pancreatitis; Gastroesophageal Reflux Disease (GERD); gastroparesis. Robotic surgery

Karen E. Gibbs, MD, FACS, FASMBS, FABQAURP, DABOM  is the current Chair of Surgery at Yale New Haven Health - Bridgeport Hospital — a destination site for fully-integrated digestive health care. Appointed to the position in September of 2021, she is the first black female Chair of Surgery in U.S. history. Dr. Gibbs specializes in laparoscopic, bariatric, foregut and endocrine procedures. Her clinical practice and research focuses on advancing the complex and integrated understanding of weight loss for the management and reversal of obesity-related disease and disorders of aging, including diabetes, and sleep apnea.Prior to Yale, Dr. Gibbs led several initiatives at Northwell Health, where she served as Associate Chair for the Department of Surgery; Chief of General, MIS & Bariatric Surgery; Director of the General Surgery Residency Program and the Advanced GI MIS Fellowship; and Director of Performance Improvement & Quality and Associate Medical Director for Quality at Staten Island University Hospital.  Dr. Gibbs received a bachelor degree from Boston University, attended Tufts University Medical School and completed her postdoctoral training at Montefiore Medical Center, Albert Einstein College of Medicine. She is a Board Certified General Surgeon and is fellowship-trained in Minimally Invasive and Bariatric Surgery; she is also Board Certified in Obesity Medicine.

Dr. Amit Khanna is an Assistant Professor in the Yale School of Medicine Department of Surgery. He serves as Director of Colon and Rectal Surgery for the Bridgeport region, and is responsible for leading the provision of colorectal surgical services across the area, in collaboration with the Digestive Health service line and Smilow Cancer Hospital Network teams. Dr. Khanna has more than 20 years of experience as a high-volume surgeon, specializing in the minimally invasive treatment and management of inflammatory bowel disease, colorectal malignancy, and anorectal diseases.

Dr. Leeds is an Assistant Professor in the Department of Surgery's Division of Colon & Rectal Surgery. His clinical practice broadly covers benign and malignant diseases of the colon, rectum, and anus. In addition, he leads a clinical research lab focused on identifying and optimizing modifiable risk factors of abdominal surgery. After obtaining an undergraduate degree at Princeton, Dr. Leeds taught high school science in Memphis, Tennessee with Teach For America. Dr. Leeds then went on to medical school at Emory University and completed clinical training in general surgery at The Johns Hopkins Hospital. He then finished subspecialty training in colon and rectal surgery at the Cleveland Clinic in Cleveland, Ohio. Along with his clinical training, Dr. Leeds has also obtained additional post-graduate degrees in business administration at the University of Oxford and clinical investigation at Johns Hopkins Bloomberg School of Public Health.

Walter E Longo, MD, MBA , FACS, FASCRS, Is one of five Yale surgeons who is board-certified specifically in colorectal cancer. He earned his medical degree from New York Medical College. He is fellowship trained and is a Board Certified General Surgeon and a Board Certified Colon and Rectal Surgeon. Dr. Longo is committed to providing patients with the highest standards for the diagnosis and medical and surgical management of the diseases of the colon, rectum, and anus using minimally invasive techniques. Watch a video with Dr. Walter Longo >>He specializes in screening and management of colon cancer; rectal cancer; anal cancer; sphincter preserving surgery; transanal removal of cancer; diverticulitis; inflammatory bowel disease; stricturoplasty; bowel resection; ostomy; polyposis syndromes and adenomatous polyps; hemorrhoids; fissures; fistulas; anal abscesses; disorders of continence; and pelvic floor disorders.

Dr. Anne Mongiu is an Assistant Professor in the Department of Surgery, whose clinical interests span the breadth of benign and malignant colon, rectal, pelvic and anal surgery. She completed her medical and doctoral degrees at Northwestern University, where her research was focused upon understanding mechanisms of cell motility. She completed her residency in General Surgery at Brigham and Women’s Hospital/Harvard Medical School, and then pursued a fellowship in Colon and Rectal Surgery at the University of Louisville, where she focused on minimally invasive (robotic) techniques for treating IBD, diverticular disease, and colorectal cancer.

Dr. John Morton is the System Lead for Surgical Quality and Bariatric Services in the Yale New Haven Health System of 6 hospitals and Vice-Chair for Quality, Division Chief for Bariatric and Minimally Invasive Surgery and Professor in the Department of Surgery at the Yale School of Medicine. He served as Chief of Bariatric and Minimally Invasive Surgery, Clinic Chief for the Bariatric and Metabolic Inter-Disciplinary Clinic and Director of Bariatric and Minimally Invasive Surgery Fellowship at Stanford University School of Medicine from 2003-2019. Dr. Morton received undergraduate, Masters in Public Health, and Medical Doctor Degrees from Tulane University and a Masters in Health Administration from University of Washington. He was the first surgical resident to receive a Robert Wood Johnson Clinical Scholar Fellowship in the program’s history at University of Washington and also completed an advanced laparoscopic surgery fellowship at University of North Carolina, Chapel Hill.  He served on Capitol Hill as Senator Bill Frist’s Health Policy Intern. He is a Diplomate of both the American Board of Surgery and American Board of Obesity Medicine and certified in Medical Quality by the American College of Medical Quality.  He has published over 173 articles and 21 book chapters with over 300 national and international presentations.  He led 5 site FDA Pivotal Trials and has received funding from National Institutes of Health and Gordon and Betty Moore Foundation. He has served as editor of five books: Quality in Obesity Treatment, Morbid Obesity: Perioperative Management, The ASMBS Textbook of Bariatric Surgery, 1st and 2nd editions and SAGES Handbook on Quality, Patient Safety and Outcomes. Furthermore, he is Clinical Editor for Bariatric Times (12,000 readership) and serves on 11 editorial boards including Obesity Surgery, Surgery for Obesity and Related Diseases, American College of Surgeons Case Studies in Surgery, and World Journal of Gastroenterology. His research efforts have been recognized by 28 research awards from 5 different surgical societies. As a teacher, Dr. Morton has received 5 teaching awards at Stanford in 8 years including the 2008 Arthur Bloomfield Clinical Teacher of the Year & 2011 Henry J. Kaiser Teaching Award.  Dr. Morton has the unique distinction of having served as Surgical Quality Director for two Top 20 US News & World Report Honor Roll Hospitals.  He is the inaugural national Chair of the Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program (MBSAQIP), a collaboration for 800 hospitals between the American Society of Metabolic and Bariatric Surgery and the American College of Surgeons. He has overseen 3 national standards, establishment of the clinical registry, and 3 national quality improvement projects within MBSAQIP. From 2014-18, the Stanford Bariatric Surgery program was noted to be Exemplary in five different categories by MBSAQIP. From 2014-5, he served as elected President of the American Society of Metabolic and Bariatric Surgery (ASMBS) composed of over 4000 members from 52 countries. In 2017, he received the highest honor accorded to a bariatric surgeon with the ASMBS Foundation Award for Outstanding Achievement and in 2019 received the Walter Pories Award. With over 3500 bariatric surgeries performed, he has been recognized as a bariatric surgery leader by Agency for Healthcare Research and Quality, RAND, American College of Surgeons, Who’s Who and America’s Top Surgeons. His clinical skills have been recognized as being named Castle Connolly’s Physician of the Year for Clinical Excellence in 2012. Dr. Morton also founded the first obesity related Political Action Committee, Obesity PAC on behalf of the American Society for Metabolic and Bariatric Surgery and Chair of the National Obesity Collaborative Care Summit for 35 Different Medical Societies.

Dr. Haddon Pantel, MD, is a fellowship trained colorectal surgeon. He treats benign, inflammatory, and cancerous diseases of the colon, rectum, and anus, including such problems as colon cancer, rectal cancer, diverticulitis and inflammatory bowel disease. He earned his medical degree from the University of Vermont followed by a General Surgery Residency at Lahey Clinic, and he subsequently completed fellowship training in Colon and Rectal Surgery at the Lahey Clinic as well. He is a Fellow if the American College of Surgeons and is board certified in both General Surgery and Colon and Rectal Surgery.

Dr. James Passarelli was born in New Haven CT and attended the Hopkins School and Tufts University. He graduated from New York Medical College in 1989 and did his surgical training at UPSTATE in Syracuse NY. His specific interests include laparoscopic surgery, hernia repairs and colon and rectal surgery.

Dr. Yavorek is a Clinical Instructor in Surgery and has over 25 years of clinical experience and resident training in New Haven. He graduated from Jefferson Medical College and served his surgical residency at Monmouth Medical Center in Long Branch, NJ and his colon and rectal surgery fellowship at Grant Medical Center in Columbus ,OH. Dr. Yavorek is board certified by the American Board of Surgery and the American Board of Colon and Rectal Surgery and is a fellow of both organizations. Most recently he was Site Director of Colon and Rectal Surgery at the St. Raphael's Campus of YNHH and he has assumed the role of Medical Director of Colon and Rectal Surgery at Lawrence and Memorial Hospital. He specializes in benign and malignant diseases of the colon, rectum and anus and has been performing minimally invasive colorectal surgery for 25 years with a special interest in robotic surgery for colon and rectal cancers.