2025

• Sand, Trond Halfdan; Uglem, Martin; Johnsen, Gjermund; Grøtting, Arnstein; Dunker, Øystein; Sandvik, Jorunn. (2025) Sensory Nerve Conduction Amplitudes and Z-Compounds Depend on Body Mass Index in Overweight and Obese Individuals. Muscle and Nerve
  Vitenskapelig artikkel
• Hyldmo, Åsne Ask; Hoff, Dag Arne Lihaug; Wibe, Arne; Bjerkan, Kirsti Kverndokk; Nymo, Siren; Johnsen, Gjermund. (2025) Chronic Abdominal Pain and Gastrointestinal Symptoms 12 Years After Primary Roux-en-Y Gastric Bypass: A Cross-Sectional Controlled Study. Obesity Surgery
  Vitenskapelig artikkel
• Barkhall, Eirin Rosø; Tro, Johanne; Sandvik, Jorunn; Nymo, Siren; Kulseng, Bård Eirik; Johnsen, Gjermund. (2025) Lipid Changes 10–15 Years After Roux-en-Y Gastric Bypass: A Prospective Observational Study. Obesity Surgery
  Vitenskapelig artikkel
• Ericson, Jessica; Klevebro, Fredrik; Sunde, Berit; Szabo, Eva; Halldestam, Ingvar; Smedh, Ulrika. (2025) Nutritional outcomes and impact of malnutrition in a randomised comparison between standard and prolonged time to surgery after neoadjuvant chemoradiotherapy for oesophageal cancer. European Journal of Surgical Oncology
  Vitenskapelig artikkel

2024

• Brudeseth, Simen; Sandvik, Jorunn; Nymo, Siren; Johnsen, Gjermund; Kulseng, Bård Eirik; Hoff, Dag Arne Lihaug. (2024) The Prevalence of Bradycardia 12 Years After Roux-en-Y Gastric Bypass for Severe Obesity. Obesity Surgery
  Vitenskapelig artikkel
• Bjerkan, Kirsti Kverndokk; Sandvik, Jorunn; Nymo, Siren; Johnsen, Gjermund; Hyldmo, Åsne Ask; Kulseng, Bård Eirik. (2024) Postbariatric hypoglycemia, abdominal pain and gastrointestinal symptoms after Roux-en-Y gastric bypass explored by continuous glucose monitoring. Obesity Research and Clinical Practice
  Vitenskapelig artikkel
• Sand, Trond Halfdan; Grøtting, Arnstein; Uglem, Martin; Augestad, Nils; Johnsen, Gjermund; Sandvik, Jorunn. (2024) Neuropathy 10–15 years after Roux-en-Y gastric bypass for severe obesity: A community-controlled nerve conduction study. Clinical Neurophysiology Practice (CNP)
  Vitenskapelig artikkel
• Hedberg, Jakob; Sundbom, Magnus; Edholm, David; Aahlin, Eirik Kjus; Szabo, Eva; Lindberg, Fredrik. (2024) Randomized controlled trial of nasogastric tube use after esophagectomy: Study protocol for the kinetic trial. Diseases of the esophagus
  Fagartikkel

2023

• Nilsson, K.; Klevebro, F.; Sunde, B.; Rouvelas, I.; Lindblad, M.; Szabo, E.. (2023) Oncological outcomes of standard versus prolonged time to surgery after neoadjuvant chemoradiotherapy for oesophageal cancer in the multicentre, randomised, controlled NeoRes II trial. Annals of Oncology
  Vitenskapelig artikkel
• Søfteland, Eirik Østensen; Aasebøstøl, Anne Kristin; Johnsen, Gjermund; Bringeland, Erling Audun. (2023) Endoluminal treatment for Zenker’s diverticulum–a population-based observational study. Scandinavian Journal of Gastroenterology
  Vitenskapelig artikkel
• Bjerkan, Kirsti Kverndokk; Sandvik, Jorunn; Nymo, Siren; Græslie, Hallvard; Johnsen, Gjermund; Mårvik, Ronald. (2023) Vitamin and Mineral Deficiency 12 Years After Roux-en-Y Gastric Bypass a Cross-Sectional Multicenter Study. Obesity Surgery
  Vitenskapelig artikkel
• Nymo, Siren; Lundanes, Julianne; Eriksen, Kevin; Aukan, Marthe Isaksen; Rehfeld, Jens Frederik; Holst, Jens Juul. (2023) Suboptimal Weight Loss 13 Years After Roux-en-Y Gastric Bypass Is Associated with Blunted Appetite Response. Obesity Surgery
  Vitenskapelig artikkel

2022

• Belgau, Ingrid Martine; Johnsen, Gjermund; Græslie, Hallvard; Mårvik, Ronald; Nymo, Siren; Bjerkan, Kirsti Kverndokk. (2022) Frequency of cholelithiasis in need of surgical or endoscopic treatment a decade or more after Roux-en-Y gastric bypass. Surgical Endoscopy
  Vitenskapelig artikkel
• Bjerkan, Kirsti Kverndokk; Sandvik, Jorunn; Nymo, Siren; Græslie, Hallvard; Johnsen, Gjermund; Mårvik, Ronald. (2022) The Long-Term Impact of Postoperative Educational Programs on Weight Loss After Roux-en-Y Gastric Bypass. Obesity Surgery
  Vitenskapelig artikkel
• Nymo, Siren; Lundanes, Julianne; Aukan, Marthe Isaksen; Sandvik, Jorunn; Johnsen, Gjermund; Græslie, Hallvard. (2022) Diet and physical activity are associated with suboptimal weight loss and weight regain 10–15 years after Roux-en-Y gastric bypass: A cross-sectional study. Obesity Research and Clinical Practice
  Vitenskapelig artikkel
• Sandvik, Elfrid Christine Smith; Aasarød, Kristin Matre; Johnsen, Gjermund; Hoff, Dag Arne Lihaug; Kulseng, Bård Eirik; Hyldmo, Åsne Ask. (2022) The Effect of Roux-en-Y Gastric Bypass on Non-Alcoholic Fatty Liver Disease Fibrosis Assessed by FIB-4 and NFS Scores—An 11.6-Year Follow-Up Study. Journal of Clinical Medicine
  Vitenskapelig artikkel
• Nymo, Siren; Lundanes, Julianne; Aukan, Marthe Isaksen; Sandvik, Jorunn; Johnsen, Gjermund; Græslie, Hallvard. (2022) Diet and physical activity are associated with suboptimal weight loss and weight regain 10–15 years after Roux-en-Y gastric bypass: A cross-sectional study. Obesity Research and Clinical Practice
  Vitenskapelig artikkel

2021

• Sandvik, Jorunn; Bjerkan, Kirsti Kverndokk; Græslie, Hallvard; Hoff, Dag Arne Lihaug; Johnsen, Gjermund; Kløckner, Christian. (2021) Iron Deficiency and Anemia 10 Years After Roux-en-Y Gastric Bypass for Severe Obesity. Frontiers in Endocrinology
  Vitenskapelig artikkel
• Strømmen, Magnus; Kløckner, Christian; Bjerkan, Kirsti Kverndokk; Græslie, Hallvard; Hoff, Dag Arne Lihaug; Johnsen, Gjermund. (2021) Characteristics of Patients Reporting Presumed Problematic Drinking Behavior After Gastric Bypass: Exploring Long-Term Data From the BAROBS Study. Frontiers in Endocrinology
  Vitenskapelig artikkel

2020

• Nilsson, Klara; Klevebro, Fredrik; Rouvelas, Ioannis; Lindblad, Mats; Szabo, Eva; Halldestam, Ingvar. (2020) Surgical Morbidity and Mortality From the Multicenter Randomized Controlled NeoRes II Trial: Standard Versus Prolonged Time to Surgery After Neoadjuvant Chemoradiotherapy for Esophageal Cancer. Annals of Surgery
  Vitenskapelig artikkel

2019

• Storli, Per Even; Johnsen, Gjermund; Juel, Ingebjørg Soterud; Grønbech, Jon Erik; Bringeland, Erling Audun. (2019) Impact of increased resection rates and a liver parenchyma sparing strategy on long-term survival after surgery for colorectal liver metastases. A population-based study. Scandinavian Journal of Gastroenterology
  Vitenskapelig artikkel
• Sunde, Berit; Johnsen, Gjermund; Jacobsen, Anne-Birgitte; Glenjen, Nils; Friesland, Signe; Lindblad, Mats. (2019) Effects of neoadjuvant chemoradiotherapy vs chemotherapy alone on the relief of dysphagia in esophageal cancer patients: secondary endpoint analysis in a randomized trial. Diseases of the esophagus
  Vitenskapelig artikkel
• Nymo, Siren; Johnsen, Gjermund; Mårvik, Ronald; Græslie, Hallvard; Kulseng, Bård Eirik; Sandvik, Jorunn. (2019) Patient satisfaction more than ten years after Roux-en-Y gastric bypass. Obesity Surgery
  Sammendrag/Abstract
• Döbeln, Gabriella Alexandersson von; Klevebro, Fredrik; Jacobsen, Anne-Birgitte; Johannessen, Hans Olaf; Nielsen, Niels Hilmer; Johnsen, Gjermund. (2019) Neoadjuvant chemotherapy versus neoadjuvant chemoradiotherapy for cancer of the esophagus or gastroesophageal junction: long-term results of a randomized clinical trial. Diseases of the esophagus
  Vitenskapelig artikkel
• Sunde, Berit; Klevebro, Fredrik; Johar, A; Johnsen, Gjermund; Jacobsen, Anne-Birgitte; Glenjen, Nils. (2019) Health-related quality of life in a randomized trial of neoadjuvant chemotherapy or chemoradiotherapy plus surgery in patients with oesophageal cancer (NeoRes trial). British Journal of Surgery
  Vitenskapelig artikkel
• Våpenstad, Cecilie; Hofstad, Erlend Fagertun; Bernstein, Tor Eivind; Aadahl, Petter; Johnsen, Gjermund; Mårvik, Ronald. (2019) Optimal timing of assessment tasks depending on experience level of surgical trainees. MITAT. Minimally invasive therapy & allied technologies
  Vitenskapelig artikkel

2017

• Våpenstad, Cecilie; Hofstad, Erlend Fagertun; Bø, Lars Eirik; Kuhry, Esther; Johnsen, Gjermund; Mårvik, Ronald. (2017) Lack of transfer of skills after virtual reality simulator training with haptic feedback. MITAT. Minimally invasive therapy & allied technologies
  Vitenskapelig artikkel

2016

• Döbeln, Gabriella Alexandersson von; Nilsson, Magnus; Adell, Gunnar; Johnsen, Gjermund; Hatlevoll, Ingunn; Tsai, Jon. (2016) Pulmonary function and cardiac stress test after multimodality treatment of esophageal cancer. Practical Radiation Oncology
  Vitenskapelig artikkel
• Chen, Duan; Olsen, Magnus Kringstad; Strømmen, Magnus; Johannessen, Helene; Bjøru, Hege Tevik; Salater, Sissel. (2016) Intragastric Injection of Botulinum Toxin a to Treat Obesity: Mechanism of Action and a Randomized, Double-Blind, Placebo-Controlled Phase II Trial With Open-Label Extension Study. Gastroenterology
  Sammendrag/Abstract
• Klevebro, Fredrik; Döbeln, Gabriella Alexandersson von; Wang, Na; Johnsen, Gjermund; Jacobsen, Anne-Birgitte; Friesland, Signe. (2016) A randomized clinical trial of neoadjuvant chemotherapy versus neoadjuvant chemoradiotherapy for cancer of the oesophagus or gastro-oesophageal junction. Annals of Oncology
  Vitenskapelig artikkel

2015

• Shikora, Scott A.; Toouli, James; Herrera, Miguel F.; Kulseng, Bård Eirik; Brancatisano, Roy; Kow, Lilian. (2015) Intermittent vagal nerve block for improvements in obesity, cardiovascular risk factors, and glycemic control in patients with type 2 diabetes mellitus: 2-year results of the VBLOC DM2 Study. Obesity Surgery
  Vitenskapelig artikkel
• Shikora, Scott A.; Toouli, James; Herrera, Miguel F.; Kulseng, Bård Eirik; Brancatisano, Roy; Kow, Lilian. (2015) Erratum to: Intermittent vagal nerve block for improvements in obesity, cardiovascular risk factors, and glycemic control in patients with type 2 diabetes mellitus: 2-year results of the VBLOC DM2 Study. Obesity Surgery
  Errata
• Klevebro, Fredrik; Johnsen, Gjermund; Johnson, Egil; Viste, Asgaut; Myrnäs, Torbjörn; Szabo, Eva. (2015) Morbidity and mortality after surgery for cancer of the oesophagus and gastro-oesophageal junction: A randomized clinical trial of neoadjuvant chemotherapy vs. neoadjuvant chemoradiation. European Journal of Surgical Oncology
  Vitenskapelig artikkel

2013

• Kodama, Yosuke; Johannessen, Helene; Furnes, Marianne Waldum; Zhao, Chun-Mei; Johnsen, Gjermund; Mårvik, Ronald. (2013) Mechanistic Comparison between Gastric Bypass vs. Duodenal Switch with Sleeve Gastrectomy in Rat Models. PLOS ONE
  Vitenskapelig artikkel
• Bringeland, Erling Audun; Wasmuth, Hans; Johnsen, Gjermund; Johnsen, Tommy; Juel, Ingebjørg Soterud; Mjønes, Patricia Gjertrud. (2013) Outcomes among patients treated for gastric adenocarcinoma during the last decade. Journal of Surgical Oncology
  Vitenskapelig artikkel
• Våpenstad, Cecilie; Hofstad, Erlend Fagertun; Bø, Lars Eirik; Chmarra, Magdalena Karolina; Kuhry, Esther; Johnsen, Gjermund. (2013) Limitations of haptic feedback devices on construct validity of the LapSim® virtual reality simulator. Surgical Endoscopy
  Vitenskapelig artikkel
• Shikora, S.; Toouli, J.; Herrera, M.F.; Kulseng, Bård Eirik; Zulewski, H.; Brancatisano, R.. (2013) Vagal blocking improves glycemic control and elevated blood pressure in obese subjects with type 2 diabetes mellitus. Journal of Obesity
  Vitenskapelig artikkel

2012

• Langø, Thomas; Vijayan, Sinara; Rethy, Anna; Våpenstad, Cecilie; Solberg, Ole Vegard; Mårvik, Ronald. (2012) Navigated laparoscopic ultrasound in abdominal soft tissue surgery: technological overview and perspectives. International Journal of Computer Assisted Radiology and Surgery
  Vitenskapelig oversiktsartikkel/review
• Tweden, K; Toouli, J; Herrera, M; Kulseng, Bård Eirik; Brancatisano, R; Pantoja, J P. (2012) VAGAL BLOCKING: TREATMENT OF OBESITY RELATED TYPE 2 DIABETES AND BLOOD PRESSURE-18 MONTH RESULTS. Obesity Surgery
  Sammendrag/Abstract
• Kodama, Yosuke; Johannessen, Helene; Furnes, Marianne Waldum; Zhao, Chun-Mei; Johnsen, Gjermund; Mårvik, Ronald. (2012) Gastric Bypass and Duodenal Switch Cause Body Weight Loss Through Different Mechanisms in Rats. Gastroenterology
  Sammendrag/Abstract
• Johannessen, Helene; Kodama, Yosuke; Zhao, Chun-Mei; Johnsen, Gjermund; Mårvik, Ronald; Kulseng, Bård Eirik. (2012) Evidence for the Hindgut Hypothesis After Ileal Interposition Associated With Sleeve Gastrectomy: Increased Number of GLP-1-Producing Cells in Interposed Ileum and Pancreatic Islets in Rats. Gastroenterology
  Sammendrag/Abstract
• Johannessen, Helene; Kodama, Yosuke; Zhao, Chun-Mei; Johnsen, Gjermund; Mårvik, Ronald; Kulseng, Bård Eirik. (2012) Altered Eating Behavior by Subdiaphragmatic Truncal Vagus Nerve Stimulation in Rats. Gastroenterology
  Sammendrag/Abstract
• Johannessen, Rune; Petersen, Hermod; Olberg, Petter; Johnsen, Gjermund; Fjøsne, Ulf; Kleveland, Per Martin. (2012) Airway symptoms and sleeping difficulties in operated and non-operated patients with gastroesophageal reflux disease. Scandinavian Journal of Gastroenterology
  Vitenskapelig artikkel

2011

• Farup, Per Grønaas; Blix, Ivar; Førre, Sigurd; Johnsen, Gjermund; Lange, Ove Juel; Johannessen, Rune. (2011) What causes treatment failure - the patient, primary care, secondary care or inadequate interaction in the health services?. BMC Health Services Research
  Vitenskapelig artikkel

1998

• Haug, Erik Skaaheim; Sæther, Ola Dalsegg; Ødegård, Asbjørn; Johnsen, Gjermund; Myhre, Hans Olav. (1998) Chylous complications after abdominal aortic surgery. International Angiology
  Vitenskapelig artikkel