Meckel's diverticulum is the most common gastrointestinal anomaly, often remaining asymptomatic but occasionally resulting in bowel obstruction. Herein, we present a case of a 6-year-old girl with an internal hernia caused by Meckel's diverticulum and mesenteric diverticular band as a rare cause of small bowel obstruction. Preoperative imaging diagnosis of this disease has been reported to be difficult. However, a detailed retrospective CT evaluation of the presented case confirmed key diagnostic findings, including identifying Meckel's diverticulum, strangulated small intestine, and findings suggesting ischemia. A meticulous CT evaluation, keeping in mind that internal hernia due to Meckel's diverticulum and mesodiverticular band is a rare cause of small bowel obstruction, is crucial. Such a detailed CT evaluation may contribute to an accurate and rapid preoperative diagnosis.journal articl

Kobayashi, Yuki

Kumazawa, Mariko

Kuwashima, Shigeko

Sakurai, Ryosuke

Soga, Shigeyoshi

Suzuki, Atsushi

Suzuki, Kan

Watanabe, Shun

English

Dokkyo Medical University Repository / 獨協医科大学リポジトリ

DKMJDokkyo Medical Journal4(1): 88-92, 2025Case ReportCT Findings of Complex Small Bowel Obstruction Due toInternal Hernia Caused by Meckel’s Diverticulum withMesodiverticular BandMariko Kumazawa1), Shigeko Kuwashima1), Ryosuke Sakurai1), Atsushi Suzuki1), Yuki Kobayashi1),Shun Watanabe2), Kan Suzuki2), Shigeyoshi Soga1)1) Department of Radiology, Dokkyo Medical University, Tochigi, Japan2) Division of Pediatric Surgery, Dokkyo Children’s Medical Center, Dokkyo Medical University, Tochigi, JapanSummaryMeckel’s diverticulum is the most common gastrointestinal anomaly, often remaining asymptomatic but oc-casionally resulting in bowel obstruction. Herein, we present a case of a 6-year-old girl with an internal herniacaused by Meckel’s diverticulum and mesenteric diverticular band as a rare cause of small bowel obstruction.Preoperative imaging diagnosis of this disease has been reported to be difficult. However, a detailed retro-spective CT evaluation of the presented case confirmed key diagnostic findings, including identifyingMeckel’s diverticulum, strangulated small intestine, and findings suggesting ischemia. A meticulous CT evalu-ation, keeping in mind that internal hernia due to Meckel’s diverticulum and mesodiverticular band is a rarecause of small bowel obstruction, is crucial. Such a detailed CT evaluation may contribute to an accurate andrapid preoperative diagnosis.Key Words: computed tomography, small bowel obstruction, Meckel’s diverticulum, internal hernia, meso-diverticular bandIntroductionMeckel’s diverticulum (MD) is the most commoncongenital malformation of the gastrointestinal tract,reported to be present in 2% of the population1). Mostpatients remain asymptomatic, but occasionally, smallbowel obstruction may occur due to MD. MD is one ofthe essential differential causes of small bowel obstruc-tion, especially in children2) and rarely in adults3).CT is a sensitive modality for diagnosing smallbowel obstruction4). However, small bowel obstructionassociated with MD is rare, and data on its CT find-ings are limited to date. The causes of small bowel ob-struction due to MD are diverse, including intussuscep-tion of an inverted MD, volvulus, Littre’s hernia, andinternal herniation of the small bowel underneath themesodiverticular band (MDB), further complicating im-aging diagnosis5,6). Additionally, CT is performed lessfrequently in children, who are more sensitive to radia-tion exposure than adults, further limiting its findings.Received March 11, 2024; accepted May 25, 2024; advance publication by J-STAGE March 27, 2025https://doi.org/10.51040/dkmj.2024-011Reprint requests to: Shigeyoshi Sogas-soga@dokkyomed.ac.jpDepartment of Radiology, Dokkyo Medical University School of Medicine, 880 Kita-Kobayashi, Mibu, Tochigi 321-0293 Japan89Bowel obstruction due Meckel’s diverticulum4 (1) (2025)Figure　1　Contrast-enhanced coronal CT imageDilated (asterisks) and collapsed (white arrows) small bowelloops are seen, suggesting small bowel obstruction. Moder-ate amounts of ascites are also seen.Figure　2　Intraoperative photographThe small intestine (curved arrow) is dilated with internalherniation, and the small intestinal wall is compressed atthe mesodiverticular band (arrowhead). The Meckel’s diver-ticulum is located behind the dilated intestine (dotted ar-row).Herein, we present a case of an internal herniacaused by MD with MDB as a rare cause of smallbowel obstruction. In the presented case, a detailed CTevaluation identified an MD near the site of obstruc-tion in the small intestine, and this finding may be thekey to an accurate preoperative diagnosis. CT mayplay a pivotal role in diagnosing and properly manag-ing this disease.Case PresentationA 6-year-old girl with no specific medical historypresented to our emergency room with abdominal painand vomiting.An abdominal radiograph revealed significant boweldilation. Subsequent CT showed a markedly dilatedand collapsed small intestine, suggesting small bowelobstruction (Fig. 1). Wall thickening of the distal smallintestine and moderate ascites were also observed. Al-though the cause of the small bowel obstruction wasnot clear at this point, CT findings prompted the deci-sion for emergency surgery. Laparoscopic surgery wasattempted; however, due to marked intestinal dilata-tion, a sufficient field of view could not be obtained.Consequently, open surgery was performed.Intraoperatively, a 5 cm MD was found in the distalileum 35 cm proximal from the ileocecal valve, and a1.5 cm long fibrous band (MDB) at the tip of the MDwas attached to the mesentery. The small intestinewas ischemic due to an internal hernia in the herniagate formed between the MD, mesodiverticular band(MDB), and mesentery (Fig. 2 and 3). Intraoperative ex-cision of the MDB led to the release of the strangula-tion of the small intestine, and improvement in thecolor tone and blood flow was confirmed. Subse-quently, a wedge resection of the MD was performed.The patient experienced an uneventful recovery andwas discharged one week after surgery.In the presented case, the cause of the small bowelobstruction was not determined preoperatively. How-ever, a detailed retrospective evaluation of the preop-erative CT using thin-section images and multiplanarreformation revealed a tubular blind-ended structurewith a similar density to the small intestine in the vi-cinity of the area of the caliber change of the dilatedsmall intestine (Fig. 4), which was deemed to be theMD and MDB. These findings were compatible withsmall bowel obstruction due to internal hernia causedby MD and MDB. In addition, some small intestinalwalls showed poor contrast enhancement (Fig. 5), sug-gesting intestinal ischemia due to strangulation.90 Mariko Kumazawa DKMJFigure　3　Schematic illustration of the mechanism of internal hernia caused by Meckel’s diverticulum and mesodiverticularbandA The mesodiverticular band (arrowhead) is attached to the tip of the Meckel’s diverticulum (dotted arrow), and mesentery serves as the hernia gate (asterisk).The gray curved arrow indicates the direction the ileum passes through the hernia gate, resulting in an internal hernia.B Internal herniation of the small bowel loop underneath the Meckel’s diverticulum and mesodiverticular band is illustrated.Figure　4　Contrast-enhanced axial CT images (A and B) demonstrate dilated (asterisks) and collapsed small bowel loops (white arrows). Image B represents a more caudal image than image A. Both images indicate a luminal structure similar to the small intestine, but with a blind end, is seen near the transition point, suggesting a Meckel’s divertic-ulum. A band (arrowhead) composed of fat density on CT was identified at the tip of Meckel’s diverticulum (dotted arrow), which was likely considered a mesodiverticular band (C).91Bowel obstruction due Meckel’s diverticulum4 (1) (2025)Figure　5　Contrast-enhanced coronal CT imageAreas of poor contrast effect in the mucosa (white arrows)of the dilated small bowel loops suggest ischemia. Collapsedsmall bowel loops and ascites can also be seen.DiscussionThis case provides two valuable clinical suggestions:internal hernia due to MD and MDB should be consid-ered a rare cause of small bowel obstruction, and iden-tification of MD through detailed CT evaluation canplay an important role in accurate preoperative diag-nosis and appropriate patient management.First, although the etiology of small bowel obstruc-tion is diverse, MD with MDB has been reported as arare cause3). The MDB is a remnant of the vitelline ar-tery, which supplies the blood flow to the MD. Thisband extending from the tip of the diverticulum to theadjacent mesentery can trap a bowel loop and causeobstruction or volvulus7). A high mortality rate hasbeen reported in small bowel obstruction due to MDand MDB, and timely surgery is critical8). Therefore, inpatients with small bowel obstruction, MD/MDBshould be kept in mind as a rare differential diagnosis.Second, in the presented case, CT allowed the identi-fication of MD and this finding may contribute to accu-rate preoperative diagnosis. Previous reports suggestthat accurate preoperative diagnosis of internal herniacaused by MD and MDB is often difficult2,9). The mainreason for this limitation is the difficulty differentiatingnormal small bowel from Meckel’s diverticulum. How-ever, in recent years, the spatial and contrast resolu-tion of CT has improved dramatically, and there havebeen scattered reports of accurate preoperative diag-nosis using CT3,9). In the presented case, MD was notnoticed preoperatively. However, a detailed postopera-tive CT evaluation identified MD, suggesting that amore accurate preoperative diagnosis is possible if adetailed imaging evaluation is performed with this dis-ease in mind.Intriguingly, a previous study demonstrated thatMeckel’s diverticulum is identified more frequently onCT in symptomatic patients than in asymptomatic pa-tients (56.5% versus 25.8%)10). The study also showed ahigher rate of MD identification in subjects with moreintra-abdominal fat than in those with less10). In the pre-sent case, the patient was symptomatic, did not havescarce intra-abdominal fat, and had ascites. These fac-tors may have reduced the difficulty of differentiationand recognition of the bowel wall and MD.As children are more susceptible to radiation expo-sure than adults, it is crucial to minimize radiationdose by adhering to the ALARA (As Low As Reason-ably Achievable) principle during diagnostic imagingprocedures. However, CT is considered an essential di-agnostic imaging tool for small intestinal obstruction inadults. Recent advancements in radiation dose reduc-tion techniques, such as artificial intelligence-based im-age processing and photon-counting detectors, holdpromise for making CT an even more valuable tool indiagnosing and managing small bowel obstruction inpediatric patients. Further studies are needed to deter-mine the optimal balance between the risks and bene-fits of expanding CT use in children and establishingoptimal radiation dose protocol. Besides, combining CTfindings with other clinical information, physical exami-nation, and potentially other imaging modalities is cru-cial for achieving an accurate diagnosis and guidingappropriate treatment decisions.In conclusion, MD and MDB are rare causes of smallbowel obstruction, and detailed CT evaluation withthis condition in mind may contribute to accurate andrapid preoperative diagnosis.grant numbers and sources of supportnot applicableAuthor ContributionsMariko Kumazawa, Shigeko Kuwashima, andShigeyoshi Soga wrote the original manuscript. Mariko92 Mariko Kumazawa DKMJKumazawa prepared figures. Shun Watanabe and KanSuzuki faced this patient and collected data. MarikoKumazawa, Shigeyoshi Soga, Ryosuke Sakurai, AtsushiSuzuki, and Yuki Kobayashi revised the manuscript.Conflict of InterestAll authors associated with this case report have noconflict of interest.References1) Satya R, O’Malley JP: Case 86: Meckel diverticulumwith massive bleeding. Radiology 236: 836-840, 2005.2) Elsayes KM, Menias CO, Harvin HJ, et al.: Imagingmanifestations of Meckel’s diverticulum. AJR Am JRoentgenol 189: 81-88, 2007.3) Yazgan C, Sahin T, Ozmen M: Unusual cause of smallbowel obstruction: mesodiverticular band of Meckel’sdiverticulum demonstrated by CT. BJR Case Rep 3:20150255, 2017.4) Aufort S, Charra L, Lesnik A, et al.: Multidetector CTof bowel obstruction: value of post-processing. Eur Ra-diol 15: 2323-2329, 2005.5) Sharma RK, Jain VK: Emergency surgery forMeckel’s diverticulum. World J Emerg Surg 3: 27,2008.6) Ludtke FE, Mende V, Kohler H, et al.: Incidence andfrequency or complications and management ofMeckel’s diverticulum. Surg Gynecol Obstet 169: 537-542, 1989.7) Prall RT, Bannon MP, Bharucha AE: Meckel’s diver-ticulum causing intestinal obstruction. Am J Gastroen-terol 96: 3426-3427, 2001.8) Vork JC, Kristensen IB: Meckel’s diverticulum and in-testinal obstruction--report of a fatal case. Forensic SciInt 138: 114-115, 2003.9) Tutar O, Velidedeoglu M, Yanik I, et al.: Computed to-mography features of small bowel obstruction due tomesodiverticular band. JBR-BTR 97: 25-27, 2014.10) Kawamoto S, Raman SP, Blackford A, et al.: CT De-tection of Symptomatic and Asymptomatic Meckel Di-verticulum. AJR Am J Roentgenol 205: 281-291, 2015.©Dokkyo Medical Society 2025. Thisarticle is licensed under the CreativeCommons Attribution-NonCommercial-NoDerivatives4.0 International License (https://creativecommons.org/licenses/by-nc-nd/4.0/). The copyright of this article re-mains with Dokkyo Medical Society. This license allowsanyone to download, reuse, copy, reprint, or distributethe article, provided the work is attributed to the origi-nal author(s) and the source, but does not allow for thedistribution of modified versions or for commercial useswithout permission of Dokkyo Medical Society (https://dokkyomed-igakukai.jp/dkmj/)

CT Findings of Complex Small Bowel Obstruction Due to Internal Hernia Caused by Meckel's Diverticulum with Mesodiverticular Band

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CT Findings of Complex Small Bowel Obstruction Due to Internal Hernia Caused by Meckel's Diverticulum with Mesodiverticular Band

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