Abstract
Background
A Morgagni hernia is a rare congenital defect typically located in the right anterior diaphragm. These defects are usually diagnosed in childhood and repaired; however, 5% are found in adults. Then, they are usually asymptomatic and often found incidentally on chest radiography. Few cases of incarceration or strangulation in adulthood are in the literature. To our knowledge, no case of an incarcerated Morgagni hernia following a minimally invasive procedure has been reported.
Summary
A 50-year-old woman, five days postrobotic-assisted laparoscopic total abdominal hysterectomy and bilateral salpingo-oophorectomy (TAH-BSO), presented to the emergency department with a three-day history of severe epigastric abdominal pain with associated nausea, vomiting, and obstipation. The patient related a five-year history of similar, though much less severe, intermittent epigastric pain. Physical exam was notable for epigastric tenderness. A CT scan revealed an incarcerated Morgagni hernia containing a portion of the transverse colon. She underwent an emergent exploratory laparotomy with a reduction of the incarcerated transverse colon and repair of the diaphragmatic defect. Her recovery was uneventful, and all symptoms resolved.
Conclusion
Morgagni hernias are rare, usually asymptomatic, diaphragmatic hernias. We present the first known case report of an incarcerated Morgagni hernia in an adult, likely exacerbated by a robotic-assisted laparoscopic TAH-BSO. With the increase in minimally invasive procedures, we believe that previously innocuous symptoms or processes may be exacerbated by increased intraabdominal pressure due to pneumoperitoneum or patient positioning. Considering this, we believe the abdominal wall and diaphragm should be thoroughly examined for hernias during laparoscopic procedures, and previously asymptomatic diaphragmatic hernias should be evaluated for risk of incarceration. Hernia repair at the time of or prior to the minimally invasive procedure may be prudent.
Key Words
Morgagni hernia; congenital diaphragmatic hernias; incarcerated hernia
Case Description
The patient is a 50-year-old woman who presented to the emergency department (ED) with a three-day history of epigastric pain and two days of nausea, vomiting, and obstipation. Her symptoms worsened approximately 12 hours prior to presentation. She reported having undergone a robotic-assisted laparoscopic total abdominal hysterectomy with bilateral salpingo-oophorectomy (TAH-BSO) for a uterine fibroid on the same day the epigastric pain began. Moreover, she also reported having a five-year history of less severe, similar pain, which always resolved spontaneously; she believed this episode would do the same. She appeared in painful distress and showed significant epigastric tenderness upon physical examination. An abdominal and pelvic computed tomography (CT) scan was obtained in the emergency room, demonstrating a right anterior diaphragmatic hernia containing a loop of transverse colon (Figure 1). The defect was further associated with congestion and edema of the antimesenteric border of the herniated bowel (Figure 2).
Figure 1. Abdominal and Pelvic CT Scan. Published with Permission
Figure 2. CT Showing Incarcerated Morgagni Hernia. Published with Permission
Consequently, the patient was taken emergently to the operating room for an open repair of the diaphragmatic hernia. A loop of incarcerated transverse colon was identified in the hernia sac of the right anteromedial, diaphragmatic defect. The colon was decompressed distally. The colon was carefully reduced from the hernia defect and inspected. Acute inflammatory changes were noted around the herniated mesocolon. A clear, compressed transition point was also identified, consistent with the site of obstruction. No evidence of ischemia or necrosis of the colon was noted. The hernia sac was dissected, adopting a preperitoneal approach from the surrounding structures, and reduced. The diaphragmatic defect, measuring approximately 4 × 2 cm, was repaired using interrupted horizontal mattress sutures (0 Ethibond) with Teflon pledgets. Her postoperative course was uneventful. She described the complete resolution of her symptoms immediately postoperatively and later at her follow-up appointments.
Discussion
A Morgagni hernia is a congenital anterior diaphragmatic defect that arises due to a lack of fusion of the fibrotendinous elements of the diaphragm to the xiphisternum and costal margin creating the foramen of Morgagni.1 While a congenital diaphragmatic hernia occurs in about 1 in 2000-5,000 live births, a Morgagni hernia accounts only for 2% to 3% of those cases.1,2 Most patients are asymptomatic, with very few presenting with incarceration or strangulation.1,2 Morgagni hernias are rare and usually diagnosed in childhood. Though most patients are asymptomatic, surgical repair is recommended to avoid complications.3 Later in life, these patients may present with vague symptoms1 (e.g., abdominal pain, nausea, and/or vomiting), and the diagnosis of a Morgagni hernia is usually formulated later in the evaluation process.1-3 Surgical intervention is performed to repair the defect; patient recovery is often uneventful. Acute presentations of a Morgagni hernia are quite uncommon; they rarely are incarcerated.1 Given the rarity of an incarcerated Morgagni hernia, we report the first case, to our knowledge, of an incarcerated Morgagni hernia in an adult, likely exacerbated by a robotic-assisted TAH-BSO performed three days prior to presentation.
Factors that may have contributed to the transverse colon incarcerating in the diaphragmatic defect are described. First, the pneumoperitoneum during the TAH-BSO may have further displaced the colon into the hernia sac due to increased intraabdominal pressure as well as enlarging and insufflating the sac. Conditions that lead to increased intraabdominal pressure, such as cough (encouraged during the postoperative course) and pain from abdominal trauma (a recent abdominal procedure), may result in further herniation through fascial defects and, hence, lead to a worsening of the symptoms.3,4 Pneumoperitoneum has rarely been explored as a factor that exacerbates hernias in asymptomatic patients. However, a few case reports of incarcerated Spigelian hernia after laparoscopic surgery, possibly caused by the increased intra-abdominal pressure, are noted.5,6 Secondly, our patient was placed in the Trendelenburg position for the gynecologic procedure. The positioning may have placed increased pressure on the colon at the hernia sac, forcing more bowel into the defect. This may have enhanced her symptoms due to the entrapment of more bowel. Finally, general endotracheal anesthesia and paralysis during minimally invasive abdominal and pelvic procedures may relax the diaphragmatic defect leading to a potential increase in the hernia contents.
Given the increase in minimally invasive pelvic procedures with associated pneumoperitoneum and the need for Trendelenburg positioning, preoperative evaluation of a patient with an asymptomatic diaphragmatic hernia should possibly be considered. In addition, systematic evaluation of the abdominal wall and diaphragm should become a routine step in laparoscopic procedures. This would identify these hernias for intraoperative assessment and help determine the need and timing for repair. In this case, the hernia was overlooked during the index gynecologic surgery, and an examination of the abdominal wall and diaphragm would have potentially identified it. This further raises the question of whether asymptomatic diaphragmatic hernias should be repaired at the time of or before laparoscopic abdominal surgeries to avoid the risk of incarceration or strangulation.7 Few studies have previously reported incidental findings of diaphragmatic hernia.8 In their case report, Smith et al. discussed a case that was identified and repaired during laparoscopic cholecystectomy.9 Given the paucity of information for treating these incidentally found hernias during other operations, management is at the discretion of the surgical team. While most surgeons recommend repair of Morgagni hernias once a diagnosis is made, management of cases found intraoperatively during other procedures has yet to be established.
Based upon a review of the literature, we identified 24 case reports published between 1981 and to date describing incarcerated or strangulated Morgagni hernias (Table 1). Similarities to our patient included a presentation of abdominal pain and vomiting, and one case report described the patient as having epigastric tenderness. Most patients were male, and more than 90% of the incarcerated Morgagni hernias were right-sided, although they can also be found on the left side or appear bilaterally.1,2 The right-sided predominance is postulated to result from extensive left-sided pericardial attachments, which prevents the development of the hernia on this side.10 Over 60% of the cases involved incarceration of the transverse colon, and the majority of cases described using an open surgical technique.
Table 1. Reported Cases of Incarcerated or Strangulated Morgagni Hernia. Published with Permission
