The Journal of Emergency Medicine, Vol. -, No. -, pp. 1–3, 2014 Copyright Ó 2014 Elsevier Inc. Printed in the USA. All rights reserved 0736-4679/$ - see front matter
http://dx.doi.org/10.1016/j.jemermed.2013.12.004
Visual Diagnosis in Emergency Medicine
INCARCERATED MORGAGNI HERNIA: AN UNUSUAL CAUSE OF LARGE BOWEL OBSTRUCTION Harika Tirumani, MBBS,* Prashanth Saddala, MBBS,† and Najla Fasih, FRCR‡ *Dana Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, †Kurnool Medical College and Hospital, Kurnool, India, and ‡Department of Diagnostic Radiology, The Ottawa Hospital, Ottawa, Ontario, Canada Reprint Address: Harika Tirumani, MBBS, Dana Farber Cancer Institute, Harvard Medical School, 450 Brookline Avenue, Boston, MA 02215
CASE REPORT A 67-year-old woman presented to the emergency department (ED) with a 2-day history of constipation and abdominal distension and 4 h of epigastric pain. Her history was remarkable for diabetes and hypertension and absence of any surgery. Clinical examination was notable for a distended abdomen with decreased bowel sounds and absence of peritoneal signs. Laboratory investigations revealed leukocytosis and normal liver function test and pancreatic enzymes. A plain abdominal radiograph revealed an elevated right hemidiaphragm and dilated, fecal matter loaded loop of large bowel in the right flank that could be traced up to the midline in the epigastric region, where there was an abrupt cutoff of the colon (Figure 1). Other than a few loops in the left upper quadrant, the rest of the colon and all of the small bowel loops were free of any air in the lumen. Although a diagnosis of large bowel obstruction was suspected, the cause was uncertain. Computed tomography (CT) scan of the abdomen and pelvis with i.v. contrast and without oral contrast was performed. It demonstrated a large retrosternal anterior diaphragmatic hernia containing a dilated loop of transverse colon, as well as omentum with luminal narrowing of the colon at the point of entry and mild soft tissue stranding in the hernia sac, consistent with incarcerated Morgagni hernia (Figure 2). The colon
Figure 1. Supine abdominal radiograph revealing dilated right and transverse colon (asterisk), an elevated right hemidiaphragm, and a gas shadow in the midline overlying the xiphisternum (arrow).
RECEIVED: 27 August 2013; FINAL SUBMISSION RECEIVED: 25 November 2013; ACCEPTED: 2 December 2013 1
2
H. Tirumani et al.
Figure 2. Axial (A), sagittal (B), and coronal reformatted (C, D) contrast-enhanced computed tomography images demonstrating right paracardiac retrosternal herniation of the omentum and transverse colon (arrows) causing obstruction of the right and transverse colon (asterisk). Note the stranding of the omental fat, which is concerning for early ischemia (arrowhead).
proximal to the hernia was dilated and filled with fecal matter. The small bowel loops were not dilated. An emergent transabdominal laparotomy with reduction of the hernia and mesh repair of the diaphragmatic defect was performed. DISCUSSION Large-bowel obstruction is less common than smallbowel obstruction. Malignant colonic neoplasms are the most common cause of large-bowel obstruction in adults, accounting for up to 60% of cases, and often involve the sigmoid colon (1). Up to 10%–28% of colon cancers are complicated by bowel obstruction (2). The other causes include diverticular strictures, volvulus, ischemic strictures, fecal impaction, obstructed hernias, and pseudo-
obstruction. Colonic obstruction is a medical emergency that requires early recognition and prompt surgical management due to the risk of perforation and peritonitis. Morgagni hernia is a rare type of diaphragmatic hernia, accounting for 1%–2% of all diaphragmatic hernias. It occurs through the retrosternal space or Larrey’s space, often on the right side due to defective fusion of the septum transversarum with costal arches. Morgagni hernia is rare in adults, and it is seen most frequently in overweight middle-aged women. The hernia may contain omentum, transverse colon, and rarely gall bladder, stomach, and liver. Often an incidental finding, it can very rarely present with acute abdomen due to bowel obstruction, strangulation, or gastric volvulus (3 6). There are only a few case reports of incarcerated or obstructed Morgagni hernia (4 6).
Incarcerated Morgagni Hernia
Morgagni hernia is seen on chest radiograph as homogeneous right cardiophrenic angle opacity or as multiple intrathoracic bowel loops. The findings are often confused with right middle lobe collapse or consolidation, eventration, pericardial cyst, or mediastinal mass (4). CT scan is the most accurate diagnostic modality and is crucial for delineation of the retrosternal defect and the contents in the hernia sac. In addition, CT scan can demonstrate features that can suggest obstruction and compromise of the herniated bowel loops. Such features include dilatation of the bowel loops proximal to the hernia, narrow hernia sac neck, thickening of the herniated bowel loop, soft tissue stranding, and free fluid in the hernia sac. Prompt recognition of these features can avoid catastrophic bowel gangrene and perforation. Although large bowel obstruction is frequently seen on CT scan as an air-filled colon and in later stages as dilated fluid-filled small bowel loops, the fecal-loaded dilated colon without small bowel dila-
3
tation in our case suggested early obstruction. Surgery, either open or laparoscopic, is the mainstay of treatment of incarcerated Morgagni hernia (3).
REFERENCES 1. Khurana B, Ledbetter S, McTavish J, Wiesner W, Ros PR. Bowel obstruction revealed by multidetector CT. AJR Am J Roentgenol 2002;178:1139–44. 2. Tirumani SH, Ojili V, Gunabushanam G, Chintapalli KN, Ryan JG, Reinhold C. MDCT of abdominopelvic oncologic emergencies. Cancer Imaging 2013;13:238–52. 3. Chick JF, Chauhan NR, Lai JH, Khurana B. Incarcerated Morgagni hernia mimicking acute cholecystitis. Intern Emerg Med 2012; 7(Suppl. 2):S169–71. 4. Eren S, Gumus H, Okur A. A rare cause of intestinal obstruction in the adult: Morgagni’s hernia. Hernia 2003;7:97–9. 5. Gangopadhyay AN, Upadhyaya VD, Gupta DK, Sharma SP. Obstructed Morgagni’s hernia. Indian J Pediatr 2007;74:1109–10. 6. Wigfield CH, Birla R, Butt T, et al. Morgagni hernia presenting with bowel obstruction in a lung transplant recipient: case report. Transplant Proc 2008;40:3826–8.
http://dx.doi.org/10.1016/j.jemermed.2013.12.004
Visual Diagnosis in Emergency Medicine
INCARCERATED MORGAGNI HERNIA: AN UNUSUAL CAUSE OF LARGE BOWEL OBSTRUCTION Harika Tirumani, MBBS,* Prashanth Saddala, MBBS,† and Najla Fasih, FRCR‡ *Dana Farber Cancer Institute, Harvard Medical School, Boston, Massachusetts, †Kurnool Medical College and Hospital, Kurnool, India, and ‡Department of Diagnostic Radiology, The Ottawa Hospital, Ottawa, Ontario, Canada Reprint Address: Harika Tirumani, MBBS, Dana Farber Cancer Institute, Harvard Medical School, 450 Brookline Avenue, Boston, MA 02215
CASE REPORT A 67-year-old woman presented to the emergency department (ED) with a 2-day history of constipation and abdominal distension and 4 h of epigastric pain. Her history was remarkable for diabetes and hypertension and absence of any surgery. Clinical examination was notable for a distended abdomen with decreased bowel sounds and absence of peritoneal signs. Laboratory investigations revealed leukocytosis and normal liver function test and pancreatic enzymes. A plain abdominal radiograph revealed an elevated right hemidiaphragm and dilated, fecal matter loaded loop of large bowel in the right flank that could be traced up to the midline in the epigastric region, where there was an abrupt cutoff of the colon (Figure 1). Other than a few loops in the left upper quadrant, the rest of the colon and all of the small bowel loops were free of any air in the lumen. Although a diagnosis of large bowel obstruction was suspected, the cause was uncertain. Computed tomography (CT) scan of the abdomen and pelvis with i.v. contrast and without oral contrast was performed. It demonstrated a large retrosternal anterior diaphragmatic hernia containing a dilated loop of transverse colon, as well as omentum with luminal narrowing of the colon at the point of entry and mild soft tissue stranding in the hernia sac, consistent with incarcerated Morgagni hernia (Figure 2). The colon
Figure 1. Supine abdominal radiograph revealing dilated right and transverse colon (asterisk), an elevated right hemidiaphragm, and a gas shadow in the midline overlying the xiphisternum (arrow).
RECEIVED: 27 August 2013; FINAL SUBMISSION RECEIVED: 25 November 2013; ACCEPTED: 2 December 2013 1
2
H. Tirumani et al.
Figure 2. Axial (A), sagittal (B), and coronal reformatted (C, D) contrast-enhanced computed tomography images demonstrating right paracardiac retrosternal herniation of the omentum and transverse colon (arrows) causing obstruction of the right and transverse colon (asterisk). Note the stranding of the omental fat, which is concerning for early ischemia (arrowhead).
proximal to the hernia was dilated and filled with fecal matter. The small bowel loops were not dilated. An emergent transabdominal laparotomy with reduction of the hernia and mesh repair of the diaphragmatic defect was performed. DISCUSSION Large-bowel obstruction is less common than smallbowel obstruction. Malignant colonic neoplasms are the most common cause of large-bowel obstruction in adults, accounting for up to 60% of cases, and often involve the sigmoid colon (1). Up to 10%–28% of colon cancers are complicated by bowel obstruction (2). The other causes include diverticular strictures, volvulus, ischemic strictures, fecal impaction, obstructed hernias, and pseudo-
obstruction. Colonic obstruction is a medical emergency that requires early recognition and prompt surgical management due to the risk of perforation and peritonitis. Morgagni hernia is a rare type of diaphragmatic hernia, accounting for 1%–2% of all diaphragmatic hernias. It occurs through the retrosternal space or Larrey’s space, often on the right side due to defective fusion of the septum transversarum with costal arches. Morgagni hernia is rare in adults, and it is seen most frequently in overweight middle-aged women. The hernia may contain omentum, transverse colon, and rarely gall bladder, stomach, and liver. Often an incidental finding, it can very rarely present with acute abdomen due to bowel obstruction, strangulation, or gastric volvulus (3 6). There are only a few case reports of incarcerated or obstructed Morgagni hernia (4 6).
Incarcerated Morgagni Hernia
Morgagni hernia is seen on chest radiograph as homogeneous right cardiophrenic angle opacity or as multiple intrathoracic bowel loops. The findings are often confused with right middle lobe collapse or consolidation, eventration, pericardial cyst, or mediastinal mass (4). CT scan is the most accurate diagnostic modality and is crucial for delineation of the retrosternal defect and the contents in the hernia sac. In addition, CT scan can demonstrate features that can suggest obstruction and compromise of the herniated bowel loops. Such features include dilatation of the bowel loops proximal to the hernia, narrow hernia sac neck, thickening of the herniated bowel loop, soft tissue stranding, and free fluid in the hernia sac. Prompt recognition of these features can avoid catastrophic bowel gangrene and perforation. Although large bowel obstruction is frequently seen on CT scan as an air-filled colon and in later stages as dilated fluid-filled small bowel loops, the fecal-loaded dilated colon without small bowel dila-
3
tation in our case suggested early obstruction. Surgery, either open or laparoscopic, is the mainstay of treatment of incarcerated Morgagni hernia (3).
REFERENCES 1. Khurana B, Ledbetter S, McTavish J, Wiesner W, Ros PR. Bowel obstruction revealed by multidetector CT. AJR Am J Roentgenol 2002;178:1139–44. 2. Tirumani SH, Ojili V, Gunabushanam G, Chintapalli KN, Ryan JG, Reinhold C. MDCT of abdominopelvic oncologic emergencies. Cancer Imaging 2013;13:238–52. 3. Chick JF, Chauhan NR, Lai JH, Khurana B. Incarcerated Morgagni hernia mimicking acute cholecystitis. Intern Emerg Med 2012; 7(Suppl. 2):S169–71. 4. Eren S, Gumus H, Okur A. A rare cause of intestinal obstruction in the adult: Morgagni’s hernia. Hernia 2003;7:97–9. 5. Gangopadhyay AN, Upadhyaya VD, Gupta DK, Sharma SP. Obstructed Morgagni’s hernia. Indian J Pediatr 2007;74:1109–10. 6. Wigfield CH, Birla R, Butt T, et al. Morgagni hernia presenting with bowel obstruction in a lung transplant recipient: case report. Transplant Proc 2008;40:3826–8.
