Case Report of Duodenal Diverticulum and Choledochal Cyst

Case Report of Duodenal Diverticulum and Choledochal Cyst | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report Case Report of Duodenal Diverticulum and Choledochal Cyst Peng-ju Zhao, Yan Ma, Hai-bin Shi, Chuan Li This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-7295512/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background Duodenal diverticulum and choledochal cysts are rare conditions that can cause upper abdominal pain, a common symptom associated with various foregut organs. Despite their rarity, accurate diagnosis is essential as these conditions can be easily misdiagnosed due to their similar computed tomography (CT) imaging features. Case presentation: Two cases were documented: one involving a 75-year-old male with a choledochal cyst located in the pancreatic head, initially presenting as a congenital choledochal cyst type II. Due to the cyst's deep location and small size, a pancreatoduodenectomy was performed, with postoperative confirmation of a congenital choledochal cyst. The second case involved a 59-year-old male with a duodenal diverticulum. Diagnostic imaging included CT and magnetic resonance imaging (MRI), leading to surgical resection of the diverticulum due to its large size, following unsuccessful inversion attempts. Postoperative pathology confirmed the diagnosis. Both patients recovered without complications and were symptom-free during follow-up. Conclusions These cases underscore the diagnostic challenges posed by similar imaging appearances. Conservative or minimally invasive approaches should be prioritized, with surgical intervention reserved for cases where less invasive methods have been exhausted. Multidisciplinary collaboration remains crucial. Duodenal Diverticulum Choledochal Cyst Diagnostic Imaging Conservative Management Surgical Intervention Figures Figure 1 Figure 2 Figure 3 Figure 4 Background Upper abdominal pain is a common symptom originating from embryonic foregut organs, including the esophagus, stomach, pancreas, biliary system, and proximal duodenum, contributing to midline upper abdominal discomfort. Additionally, cardiac and aortic diseases can produce similar pain. Frequent causes include gastric ulcers, gallstones, and pancreatitis [ 1 ] . Although rare, duodenal diverticulum and choledochal cysts can also cause upper abdominal pain. Computed Tomography (CT) scans are generally the initial diagnostic method for such pain [ 2 ] ; however, the similar CT imaging of these diseases complicates accurate diagnosis. This paper presents cases of duodenal diverticulum and choledochal cysts, emphasizing diagnostic challenges and management strategies. Ethical Approval and accordance This study was conducted in accordance with the Declaration of Helsinki. All research data were processed anonymously and accessed by authorized personnel solely for research purposes. The study was approved by the Ethics Committee of the First Affiliated Hospital of Dali University (2025 − 1208). Case presentation Case 1 A 75-year-old male experienced recurring upper abdominal pain over a 20-day period. This pain was characterized by intermittent distension radiating to the back, unrelated to meals, and was not accompanied by symptoms such as jaundice, fever and vomiting. Physical examination revealed a symmetrical abdominal profile, absence of distension and mass. Tenderness was noted in the upper abdomen without rebound tenderness, muscle tension, or a positive Murphy's sign. There was no percussion pain in the liver and kidney regions. Bowel sounds were normal at four times per minute. Gastroscopy, doppler ultrasound of the hepatobiliary-pancreatic-spleen system, complete blood count, liver and kidney function tests, and tumor markers for the digestive system showed no abnormalities. The CT scan revealed a well-defined circular structure in the pancreatic head containing air and fluid, without significant edge enhancement (see Fig. 1). Magnetic Resonance Imaging (MRI) of the hepatobiliary and pancreatic region, combined with magnetic resonance cholangiopancreatography (MRCP), identified a cyst in the pancreatic head connected to the lower part of the common bile duct via a slender stalk (see Fig. 1). As endoscopic retrograde cholangiopancreatography (ERCP) was unavailable at our hospital, it was not performed. The preoperative diagnosis was a congenital choledochal cyst type II in adults. Conservative treatment was ineffective. Surgical options included open cyst removal or duodenal choledochal cyst anastomosis. However, during surgery, the cyst was found deeply embedded in the pancreatic head tissue and too small for the planned procedures, necessitating a pancreatoduodenectomy. Postoperative pathology confirmed a common bile duct cyst, verifying the diagnosis of a congenital choledochal cyst type II in adults (see Fig. 2). The patient recovered well postoperatively without complications such as a pancreatic fistula and was discharged on day 14 with no abdominal pain reported at the 3-month follow-up. Case 2 A 59-year-old male patient presented with recurrent upper abdominal pain persisting for one month. The patient has no history of abdominal trauma. The patient experienced colicky pain in the upper abdomen, predominantly while fasting, which intensified postprandially. There was no significant radiating pain, jaundice,fever, acid reflux, or vomiting. Physical examination revealed a symmetrical abdomen without distension and mass, a soft abdominal wall, and marked tenderness in the right upper quadrant, but no rebound tenderness, muscle guarding, or positive Murphy's sign. No percussion pain was noted in the liver and kidney areas. Bowel sounds were normal, occurring four times per minute. Gastroscopy, hepatobiliary pancreatic spleen color Doppler ultrasound, complete blood count, liver and kidney function tests, and digestive system tumor markers showed no abnormalities. A CT scan showed a well-defined circular structure in the pancreatic head primarily containing gas and fluid, with no significant edge enhancement (see Fig. 3). An MRI plain scan further suggested a diverticulum-like structure in the pancreatic head, without gas accumulation in the biliary system (see Fig. 3). The upper gastrointestinal barium meal test showed no signs of a duodenal diverticulum. The initial diagnosis suggested a duodenal diverticulum, and due to the ineffectiveness of conservative treatment, plans for open diverticulum resection were made. Surgical exploration revealed a diverticulum opening in the third part of the duodenum, which could not be inverted due to its large diameter. Consequently, a partial resection of the duodenum containing the diverticulum was performed, followed by end-to-end anastomosis. Postoperative pathology confirmed a duodenal diverticulum (see Fig. 4). The patient had a smooth postoperative recovery without complications such as anastomotic leakage, was discharged on the eighth day, and reported no abdominal pain at the three-month follow-up. Discussion Choledochal cysts are characterized by single or multiple cystic dilations of the biliary system, typically without significant obstruction. The incidence is 3–4 times higher in females and occurs at rates of 1/13,000 in Asian populations and 1/150,000 in Western populations. The etiology of choledochal cysts remains largely unknown [ 3 ] . Patients often present with non-specific right or upper abdominal pain and may occasionally exhibit jaundice, cholangitis, or pancreatitis. Todani classified choledochal cysts into five types: Type I involves cystic dilations of the common bile duct, Type II constitutes diverticula of the extrahepatic bile duct, Type III covers terminal cysts of the common bile duct, Type IV includes multiple intrahepatic and extrahepatic cysts, and Type V is known as Caroli's disease [ 4 ] . Type II is particularly rare and can be further classified based on location into upper, middle, and lower bile duct diverticula, with the lower being the least common [ 5 ] . CT imaging reveals cystic masses in the pancreatic head containing bile stasis and gas, yet without gas accumulation in the bile duct system [ 6 ] . Although ERCP has traditionally been the gold standard for diagnosing bile duct cysts, its invasive nature is leading to its replacement by MRCP [ 3 ] . Some bile duct cysts can be managed endoscopically, but many require surgical intervention to reduce the risk of complications such as cholangitis and malignancy [ 7 ] . Treatment for Type II bile duct cysts typically involves complete cyst resection, and some patients may need additional procedures, such as extrahepatic bile duct resection, hepatectomy, or pancreatoduodenectomy [ 8 ] . Duodenal diverticula form through congenital and acquired mechanisms: congenital factors include defects in the muscle layer of the intestinal wall during embryogenesis, resulting in intraluminal types; acquired factors are related to increased intra-intestinal pressure and muscle wall atrophy, leading to extraluminal types [ 9 ] . Studies indicate a prevalence of duodenal diverticula in 22% of individuals, with 95% being asymptomatic and 1–5% developing symptoms over time. Complications can include inflammation, ulcers, bleeding, cholangitis, pancreatitis, bowel obstruction, and perforation [ 10 , 11 ] . In 62% of cases, diverticula are located in the second part of the duodenum near the ampulla; 30% are in the third part, and 8% are in the fourth part [ 10 ] . The main diagnostic methods include upper gastrointestinal contrast, gastroscopy, and ERCP, though there is an increasing reliance on abdominal CT scans with intravenous and gastrointestinal contrast agents. Extraluminal diverticula appear on CT as circular structures outside the pancreatic head, containing air and/or fluid [ 12 ] . Surgery is warranted only when diverticula cause refractory pain, severe bleeding, or perforation [ 13 ] . ERCP is effective for diagnosing and treating intraluminal diverticula [ 14 ] , while surgical approaches for extraluminal types depend on their relationship with the duodenal ampulla and may involve procedures such as two-layer closure diverticula resection. Complex cases may require gastrectomy, gastrojejunostomy, duodenojejunostomy, or duodenal resection with a pylorus-preserving Whipple procedure [ 15 ] . Notably, duodenal diverticula and choledochal cysts may appear similar on CT, potentially leading to misdiagnosis. Choledochal cysts are often associated with pneumobilia, which is not typical of duodenal diverticula. Diagnosis of choledochal cysts is confirmed by gastrointestinal contrast or ERCP, whereas duodenal diverticula require ERCP or MRCP, often using multimodal imaging. Treatment of duodenal diverticula is typically conservative unless complications arise. Surgical pathways should consider organ preservation, such as diverticulum resection with anastomosis. Invasive resection is often necessary for choledochal cysts due to potential complications like cholangitis or malignancy. This report focuses on two individual cases, limiting the generalizability of the findings to broader populations. The rarity of duodenal diverticula and choledochal cysts results in limited data available to evaluate variations in presentations and outcomes across different demographics. Additionally, the decision for pancreatoduodenectomy was made due to the cyst's location; however, this approach might have been excessively aggressive without trialing less invasive diagnostics like ERCP, which was unavailable at our facility. The cases are primarily descriptive, lacking controlled comparisons or long-term follow-up data, which limits the ability to assess the long-term efficacy and risks of the surgical interventions performed. Future studies should aim for larger datasets and include multicenter trials to address these limitations for more comprehensive insights into the diagnosis and management strategies for these rare conditions. Conclusion In conclusion, duodenal diverticulum and choledochal cyst cases underscore the diagnostic challenges due to their similar imaging characteristics. Accurate diagnosis is essential to prevent unwarranted invasive procedures. It is advisable to prioritize conservative and minimally invasive approaches. Advanced imaging techniques such as MRCP can enhance diagnostic accuracy without the invasiveness of ERCP. Surgical intervention should be reserved for situations where conservative treatments are unsuccessful or complications develop. Multidisciplinary collaboration is crucial for developing effective treatment plans. Future research should focus on conducting larger studies to better understand these rare conditions and establish standardized management guidelines. Abbreviations CT: Computed Tomography;MRI: Magnetic Resonance Imaging;ERCP: Endoscopic retrograde cholangiopancreatography;MRCP: magnetic resonance cholangiopancreatography. Declarations Supplementary Information None. Acknowledgements We gratefully acknowledge all contributors to this study. We thank the Department of General Surgery at the First Affiliated Hospital of Dali University for their crucial support in data collection and analysis. Author contributions PJZ and YM were major contributors in writing the manuscript. HBS collected the patient data. PJZ and CL performed both surgeries and followed up the patients. PJZ realized the scarcity of the two cases, did literature searches, and revised the manuscript. All authors read and approved the final manuscript. Funding This research was funded by the Science Research Fund of the Yunnan Provincial Department of Education. The views expressed are the authors’own and do not reflect the agency’s views. Clinical trial number not applicable. Consent to Participate Participants provided freely-given, informed consent to participate in this study, ensuring they were fully aware of the study’s objectives and procedures. This process adhered to ethical guidelines. Availability of data and materials The datasets used and/or analysed during the current study are available from the corresponding author on reasonable request. Consent for publication The patients have given their consent for publication. Written informed consent was obtained from the patients for publication of this Case report and any accompanying images. A copy of the written consent is available for review by the Editor of this journal. Competing interests The authors declare that they have no competing interests. References Robinson P, Perkins J C. Approach to patients with epigastric pain. Emergency Medicine Clinics of North America, 2016, 34(2): 191-210. Expert Panel on Gastrointestinal Imaging; Vij A, Zaheer A, Kamel IR, Porter KK, Arif-Tiwari H, Bashir MR, Fung A, Goldstein A, Herr KD, Kamaya A, Kobi M, Landler MP, Russo GK, Thakrar KH, Turturro MA, Wahab SA, Wardrop RM 3rd, Wright CL, Yang X, Carucci LR. ACR appropriateness criteria® epigastric pain. Journal of the American College of Radiology: JACR, 2021, 18(11S): S330-S339. Serin KR, Ercan LD, Ibis C, Ozden I, Tekant Y. Choledochal cysts: Management and long-term follow-up. The Surgeon, 2021, 19(4): 200-206. Al Samaraee A, Bhattacharya V. Cystic duct cyst in adults: A systematic review of the sixth entity. Surgery Today, 2023, 53(5): 527-543. Saito T, Ando H, Ishihara S, Itoi T, Urushihara N, Otsuka M, Koshinaga T, Nagakawa Y, Hamada Y, Morotomi Y. Does Congenital Biliary Dilatation Todani Type II (Diverticular Type) Really Exist? J Pediatr Surg. 2024 Feb;59(2):240-246. Tarallo N, Curti M, Molinelli V, Leonardi A, Fugazzola C. Diverticulum of common hepatic duct leading to obstructive jaundice, a case report. BJR Case Rep. 2019 Jan 4;5(2):20180105. Brown ZJ, Baghdadi A, Kamel I, Labiner HE, Hewitt DB, Pawlik TM. Diagnosis and management of choledochal cysts. HPB (Oxford). 2023 Jan;25(1):14-25. Ouaïssi M, Kianmanesh R, Belghiti J, Ragot E, Mentha G, Adham M, Troisi RI, Pruvot FR, Dugué L, Paye F, Ayav A, Nuzzo G, Falconi M, Demartines N, Mabrut JY, Gigot JF; Working Group of the French Surgical Association. Todani Type II Congenital Bile Duct Cyst: European Multicenter Study of the French Surgical Association and Literature Review. Ann Surg. 2015 Jul;262(1):130-8. Bittle MM, Gunn ML, Gross JA, Rohrmann CA. Imaging of duodenal diverticula and their complications. Curr Probl Diagn Radiol. 2012 Jan-Feb;41(1):20-9. Oukachbi N, Brouzes S. Management of complicated duodenal diverticula. J Visc Surg. 2013 Jun;150(3):173-9. Boot M, Chew K, Archer J, Sowter S, Bergamin P. Iatrogenic duodenal diverticulum perforation: a systematic review. ANZ J Surg. 2023 May;93(5):1322-1328. Oddo F, Chevallier P, Souci J, Baque J, Buckley MJ, Fabiani P, Diaine B, Coussement A. Aspects radiologiques des complications des diverticules duodénaux [Radiologic aspects of the complications of duodenal diverticula]. J Radiol. 1999 Feb;80(2):134-40. Guerra F, Foghetti D, Patriti A. Laparoscopic Duodenal Diverticulectomy via the Inframesocolic Route. J Gastrointest Surg. 2021 May;25(5):1360-1362. Eghbali E, Tarzamni MK, Shirmohammadi M, Javadrashid R, Fouladi DF. Diagnostic performance of 64-MDCT in detecting ERCP-proven periampullary duodenal diverticula. Radiol Med. 2020 Apr;125(4):339-347. Sahned J, Hung Fong S, Mohammed Saeed D, Misra S, Park IS. Duodenal Diverticulitis: To Operate or Not To Operate? Cureus. 2019 Nov 26;11(11):e6236. Additional Declarations No competing interests reported. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Additionally, cardiac and aortic diseases can produce similar pain. Frequent causes include gastric ulcers, gallstones, and pancreatitis \u003csup\u003e[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]\u003c/sup\u003e. Although rare, duodenal diverticulum and choledochal cysts can also cause upper abdominal pain. Computed Tomography (CT) scans are generally the initial diagnostic method for such pain \u003csup\u003e[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]\u003c/sup\u003e; however, the similar CT imaging of these diseases complicates accurate diagnosis. This paper presents cases of duodenal diverticulum and choledochal cysts, emphasizing diagnostic challenges and management strategies.\u003c/p\u003e\u003cp\u003eEthical Approval and accordance \u003cp\u003eThis study was conducted in accordance with the Declaration of Helsinki. All research data were processed anonymously and accessed by authorized personnel solely for research purposes. The study was approved by the Ethics Committee of the First Affiliated Hospital of Dali University (2025\u0026thinsp;\u0026minus;\u0026thinsp;1208).\u003c/p\u003e"},{"header":"Case presentation","content":"\u003cp\u003e\u003cstrong\u003eCase 1\u003c/strong\u003e\u003cp\u003eA 75-year-old male experienced recurring upper abdominal pain over a 20-day period. This pain was characterized by intermittent distension radiating to the back, unrelated to meals, and was not accompanied by symptoms such as jaundice, fever and vomiting. Physical examination revealed a symmetrical abdominal profile, absence of distension and mass. Tenderness was noted in the upper abdomen without rebound tenderness, muscle tension, or a positive Murphy's sign. There was no percussion pain in the liver and kidney regions. Bowel sounds were normal at four times per minute. Gastroscopy, doppler ultrasound of the hepatobiliary-pancreatic-spleen system, complete blood count, liver and kidney function tests, and tumor markers for the digestive system showed no abnormalities. The CT scan revealed a well-defined circular structure in the pancreatic head containing air and fluid, without significant edge enhancement (see Fig.\u0026nbsp;1). Magnetic Resonance Imaging (MRI) of the hepatobiliary and pancreatic region, combined with magnetic resonance cholangiopancreatography (MRCP), identified a cyst in the pancreatic head connected to the lower part of the common bile duct via a slender stalk (see Fig.\u0026nbsp;1). As endoscopic retrograde cholangiopancreatography (ERCP) was unavailable at our hospital, it was not performed. The preoperative diagnosis was a congenital choledochal cyst type II in adults. Conservative treatment was ineffective. Surgical options included open cyst removal or duodenal choledochal cyst anastomosis. However, during surgery, the cyst was found deeply embedded in the pancreatic head tissue and too small for the planned procedures, necessitating a pancreatoduodenectomy. Postoperative pathology confirmed a common bile duct cyst, verifying the diagnosis of a congenital choledochal cyst type II in adults (see Fig.\u0026nbsp;2). The patient recovered well postoperatively without complications such as a pancreatic fistula and was discharged on day 14 with no abdominal pain reported at the 3-month follow-up.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eCase 2\u003c/strong\u003e\u003cp\u003eA 59-year-old male patient presented with recurrent upper abdominal pain persisting for one month. The patient has no history of abdominal trauma. The patient experienced colicky pain in the upper abdomen, predominantly while fasting, which intensified postprandially. There was no significant radiating pain, jaundice,fever, acid reflux, or vomiting. Physical examination revealed a symmetrical abdomen without distension and mass, a soft abdominal wall, and marked tenderness in the right upper quadrant, but no rebound tenderness, muscle guarding, or positive Murphy's sign. No percussion pain was noted in the liver and kidney areas. Bowel sounds were normal, occurring four times per minute. Gastroscopy, hepatobiliary pancreatic spleen color Doppler ultrasound, complete blood count, liver and kidney function tests, and digestive system tumor markers showed no abnormalities. A CT scan showed a well-defined circular structure in the pancreatic head primarily containing gas and fluid, with no significant edge enhancement (see Fig.\u0026nbsp;3). An MRI plain scan further suggested a diverticulum-like structure in the pancreatic head, without gas accumulation in the biliary system (see Fig.\u0026nbsp;3). The upper gastrointestinal barium meal test showed no signs of a duodenal diverticulum. The initial diagnosis suggested a duodenal diverticulum, and due to the ineffectiveness of conservative treatment, plans for open diverticulum resection were made. Surgical exploration revealed a diverticulum opening in the third part of the duodenum, which could not be inverted due to its large diameter. Consequently, a partial resection of the duodenum containing the diverticulum was performed, followed by end-to-end anastomosis. Postoperative pathology confirmed a duodenal diverticulum (see Fig.\u0026nbsp;4). The patient had a smooth postoperative recovery without complications such as anastomotic leakage, was discharged on the eighth day, and reported no abdominal pain at the three-month follow-up.\u003c/p\u003e\u003c/p\u003e\u003cp\u003e\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eCholedochal cysts are characterized by single or multiple cystic dilations of the biliary system, typically without significant obstruction. The incidence is 3\u0026ndash;4 times higher in females and occurs at rates of 1/13,000 in Asian populations and 1/150,000 in Western populations. The etiology of choledochal cysts remains largely unknown \u003csup\u003e[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]\u003c/sup\u003e. Patients often present with non-specific right or upper abdominal pain and may occasionally exhibit jaundice, cholangitis, or pancreatitis. Todani classified choledochal cysts into five types: Type I involves cystic dilations of the common bile duct, Type II constitutes diverticula of the extrahepatic bile duct, Type III covers terminal cysts of the common bile duct, Type IV includes multiple intrahepatic and extrahepatic cysts, and Type V is known as Caroli's disease \u003csup\u003e[\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]\u003c/sup\u003e. Type II is particularly rare and can be further classified based on location into upper, middle, and lower bile duct diverticula, with the lower being the least common \u003csup\u003e[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]\u003c/sup\u003e. CT imaging reveals cystic masses in the pancreatic head containing bile stasis and gas, yet without gas accumulation in the bile duct system \u003csup\u003e[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]\u003c/sup\u003e. Although ERCP has traditionally been the gold standard for diagnosing bile duct cysts, its invasive nature is leading to its replacement by MRCP \u003csup\u003e[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]\u003c/sup\u003e. Some bile duct cysts can be managed endoscopically, but many require surgical intervention to reduce the risk of complications such as cholangitis and malignancy \u003csup\u003e[\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]\u003c/sup\u003e. Treatment for Type II bile duct cysts typically involves complete cyst resection, and some patients may need additional procedures, such as extrahepatic bile duct resection, hepatectomy, or pancreatoduodenectomy \u003csup\u003e[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eDuodenal diverticula form through congenital and acquired mechanisms: congenital factors include defects in the muscle layer of the intestinal wall during embryogenesis, resulting in intraluminal types; acquired factors are related to increased intra-intestinal pressure and muscle wall atrophy, leading to extraluminal types \u003csup\u003e[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]\u003c/sup\u003e. Studies indicate a prevalence of duodenal diverticula in 22% of individuals, with 95% being asymptomatic and 1\u0026ndash;5% developing symptoms over time. Complications can include inflammation, ulcers, bleeding, cholangitis, pancreatitis, bowel obstruction, and perforation \u003csup\u003e[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e, \u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]\u003c/sup\u003e. In 62% of cases, diverticula are located in the second part of the duodenum near the ampulla; 30% are in the third part, and 8% are in the fourth part \u003csup\u003e[\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]\u003c/sup\u003e. The main diagnostic methods include upper gastrointestinal contrast, gastroscopy, and ERCP, though there is an increasing reliance on abdominal CT scans with intravenous and gastrointestinal contrast agents. Extraluminal diverticula appear on CT as circular structures outside the pancreatic head, containing air and/or fluid \u003csup\u003e[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]\u003c/sup\u003e. Surgery is warranted only when diverticula cause refractory pain, severe bleeding, or perforation \u003csup\u003e[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e]\u003c/sup\u003e. ERCP is effective for diagnosing and treating intraluminal diverticula \u003csup\u003e[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]\u003c/sup\u003e, while surgical approaches for extraluminal types depend on their relationship with the duodenal ampulla and may involve procedures such as two-layer closure diverticula resection. Complex cases may require gastrectomy, gastrojejunostomy, duodenojejunostomy, or duodenal resection with a pylorus-preserving Whipple procedure \u003csup\u003e[\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e]\u003c/sup\u003e.\u003c/p\u003e\u003cp\u003eNotably, duodenal diverticula and choledochal cysts may appear similar on CT, potentially leading to misdiagnosis. Choledochal cysts are often associated with pneumobilia, which is not typical of duodenal diverticula. Diagnosis of choledochal cysts is confirmed by gastrointestinal contrast or ERCP, whereas duodenal diverticula require ERCP or MRCP, often using multimodal imaging. Treatment of duodenal diverticula is typically conservative unless complications arise. Surgical pathways should consider organ preservation, such as diverticulum resection with anastomosis. Invasive resection is often necessary for choledochal cysts due to potential complications like cholangitis or malignancy.\u003c/p\u003e\u003cp\u003eThis report focuses on two individual cases, limiting the generalizability of the findings to broader populations. The rarity of duodenal diverticula and choledochal cysts results in limited data available to evaluate variations in presentations and outcomes across different demographics. Additionally, the decision for pancreatoduodenectomy was made due to the cyst's location; however, this approach might have been excessively aggressive without trialing less invasive diagnostics like ERCP, which was unavailable at our facility. The cases are primarily descriptive, lacking controlled comparisons or long-term follow-up data, which limits the ability to assess the long-term efficacy and risks of the surgical interventions performed. Future studies should aim for larger datasets and include multicenter trials to address these limitations for more comprehensive insights into the diagnosis and management strategies for these rare conditions.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eIn conclusion, duodenal diverticulum and choledochal cyst cases underscore the diagnostic challenges due to their similar imaging characteristics. Accurate diagnosis is essential to prevent unwarranted invasive procedures. It is advisable to prioritize conservative and minimally invasive approaches. Advanced imaging techniques such as MRCP can enhance diagnostic accuracy without the invasiveness of ERCP. Surgical intervention should be reserved for situations where conservative treatments are unsuccessful or complications develop. Multidisciplinary collaboration is crucial for developing effective treatment plans. Future research should focus on conducting larger studies to better understand these rare conditions and establish standardized management guidelines.\u003c/p\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eCT: Computed Tomography;MRI: Magnetic Resonance Imaging;ERCP: Endoscopic retrograde cholangiopancreatography;MRCP: magnetic resonance cholangiopancreatography.\u003c/p\u003e\n"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eSupplementary Information\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eNone.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe gratefully acknowledge all contributors to this study. We thank the Department of General Surgery at the First Affiliated Hospital of Dali University for their crucial support in data collection and analysis.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003ePJZ and YM were major contributors in writing the manuscript. HBS collected the patient data. PJZ and CL performed both surgeries and followed up the patients. PJZ realized the scarcity of the two cases, did literature searches, and revised the manuscript. All authors read and approved the final manuscript.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis research was funded by the Science Research Fund of the Yunnan Provincial Department of Education. The views expressed are the authors\u0026rsquo;own and do not reflect the agency\u0026rsquo;s views.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eClinical trial number\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003enot applicable.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent to Participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eParticipants provided freely-given, informed consent to participate in this study, ensuring they were fully aware of the study\u0026rsquo;s objectives and procedures. This process adhered to ethical guidelines.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analysed during the current study are available from the corresponding author on reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe patients have given their consent for publication. Written informed consent was obtained from the patients for publication of this Case report and any accompanying images. A copy of the written consent is available for review by the Editor of this journal.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eRobinson P, Perkins J C. Approach to patients with epigastric pain. Emergency Medicine Clinics of North America, 2016, 34(2): 191-210.\u003c/li\u003e\n\u003cli\u003eExpert Panel on Gastrointestinal Imaging; Vij A, Zaheer A, Kamel IR, Porter KK, Arif-Tiwari H, Bashir MR, Fung A, Goldstein A, Herr KD, Kamaya A, Kobi M, Landler MP, Russo GK, Thakrar KH, Turturro MA, Wahab SA, Wardrop RM 3rd, Wright CL, Yang X, Carucci LR. ACR appropriateness criteria\u0026reg; epigastric pain. Journal of the American College of Radiology: JACR, 2021, 18(11S): S330-S339.\u003c/li\u003e\n\u003cli\u003eSerin KR, Ercan LD, Ibis C, Ozden I, Tekant Y. Choledochal cysts: Management and long-term follow-up. The Surgeon, 2021, 19(4): 200-206.\u003c/li\u003e\n\u003cli\u003eAl Samaraee A, Bhattacharya V. Cystic duct cyst in adults: A systematic review of the sixth entity. Surgery Today, 2023, 53(5): 527-543.\u003c/li\u003e\n\u003cli\u003eSaito T, Ando H, Ishihara S, Itoi T, Urushihara N, Otsuka M, Koshinaga T, Nagakawa Y, Hamada Y, Morotomi Y. Does Congenital Biliary Dilatation Todani Type II (Diverticular Type) Really Exist? J Pediatr Surg. 2024 Feb;59(2):240-246.\u003c/li\u003e\n\u003cli\u003eTarallo N, Curti M, Molinelli V, Leonardi A, Fugazzola C. Diverticulum of common hepatic duct leading to obstructive jaundice, a case report. BJR Case Rep. 2019 Jan 4;5(2):20180105. \u003c/li\u003e\n\u003cli\u003eBrown ZJ, Baghdadi A, Kamel I, Labiner HE, Hewitt DB, Pawlik TM. Diagnosis and management of choledochal cysts. HPB (Oxford). 2023 Jan;25(1):14-25. \u003c/li\u003e\n\u003cli\u003eOua\u0026iuml;ssi M, Kianmanesh R, Belghiti J, Ragot E, Mentha G, Adham M, Troisi RI, Pruvot FR, Dugu\u0026eacute; L, Paye F, Ayav A, Nuzzo G, Falconi M, Demartines N, Mabrut JY, Gigot JF; Working Group of the French Surgical Association. Todani Type II Congenital Bile Duct Cyst: European Multicenter Study of the French Surgical Association and Literature Review. Ann Surg. 2015 Jul;262(1):130-8. \u003c/li\u003e\n\u003cli\u003eBittle MM, Gunn ML, Gross JA, Rohrmann CA. Imaging of duodenal diverticula and their complications. Curr Probl Diagn Radiol. 2012 Jan-Feb;41(1):20-9.\u003c/li\u003e\n\u003cli\u003eOukachbi N, Brouzes S. Management of complicated duodenal diverticula. J Visc Surg. 2013 Jun;150(3):173-9.\u003c/li\u003e\n\u003cli\u003eBoot M, Chew K, Archer J, Sowter S, Bergamin P. Iatrogenic duodenal diverticulum perforation: a systematic review. ANZ J Surg. 2023 May;93(5):1322-1328.\u003c/li\u003e\n\u003cli\u003eOddo F, Chevallier P, Souci J, Baque J, Buckley MJ, Fabiani P, Diaine B, Coussement A. Aspects radiologiques des complications des diverticules duod\u0026eacute;naux [Radiologic aspects of the complications of duodenal diverticula]. J Radiol. 1999 Feb;80(2):134-40.\u003c/li\u003e\n\u003cli\u003eGuerra F, Foghetti D, Patriti A. Laparoscopic Duodenal Diverticulectomy via the Inframesocolic Route. J Gastrointest Surg. 2021 May;25(5):1360-1362. \u003c/li\u003e\n\u003cli\u003eEghbali E, Tarzamni MK, Shirmohammadi M, Javadrashid R, Fouladi DF. Diagnostic performance of 64-MDCT in detecting ERCP-proven periampullary duodenal diverticula. Radiol Med. 2020 Apr;125(4):339-347.\u003c/li\u003e\n\u003cli\u003eSahned J, Hung Fong S, Mohammed Saeed D, Misra S, Park IS. Duodenal Diverticulitis: To Operate or Not To Operate? Cureus. 2019 Nov 26;11(11):e6236. \u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Duodenal Diverticulum, Choledochal Cyst, Diagnostic Imaging, Conservative Management, Surgical Intervention","lastPublishedDoi":"10.21203/rs.3.rs-7295512/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7295512/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eBackground\u003c/h2\u003e\u003cp\u003eDuodenal diverticulum and choledochal cysts are rare conditions that can cause upper abdominal pain, a common symptom associated with various foregut organs. Despite their rarity, accurate diagnosis is essential as these conditions can be easily misdiagnosed due to their similar computed tomography (CT) imaging features.\u003c/p\u003e\u003ch2\u003eCase presentation:\u003c/h2\u003e\u003cp\u003eTwo cases were documented: one involving a 75-year-old male with a choledochal cyst located in the pancreatic head, initially presenting as a congenital choledochal cyst type II. Due to the cyst's deep location and small size, a pancreatoduodenectomy was performed, with postoperative confirmation of a congenital choledochal cyst. The second case involved a 59-year-old male with a duodenal diverticulum. Diagnostic imaging included CT and magnetic resonance imaging (MRI), leading to surgical resection of the diverticulum due to its large size, following unsuccessful inversion attempts. Postoperative pathology confirmed the diagnosis. Both patients recovered without complications and were symptom-free during follow-up.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e\u003cp\u003eThese cases underscore the diagnostic challenges posed by similar imaging appearances. Conservative or minimally invasive approaches should be prioritized, with surgical intervention reserved for cases where less invasive methods have been exhausted. Multidisciplinary collaboration remains crucial.\u003c/p\u003e","manuscriptTitle":"Case Report of Duodenal Diverticulum and Choledochal Cyst","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-10-22 19:35:11","doi":"10.21203/rs.3.rs-7295512/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"78d6a0e8-f704-4969-8d67-763a3678a364","owner":[],"postedDate":"October 22nd, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-01-14T12:23:14+00:00","versionOfRecord":[],"versionCreatedAt":"2025-10-22 19:35:11","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-7295512","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7295512","identity":"rs-7295512","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}