Paraoesophageal omental hernia

Description

A 61-year-old man with recently diagnosed gastro-oesophageal reflux disease re-presented to his primary care physician due to persisting epigastric and pharyngeal pain refractory to maximal proton pump inhibitor therapy. Examination was unremarkable. Endoscopy with biopsy showed features of resolving gastritis. CT at another institution revealed a mediastinal mass originally reported as a lipoma or a well-differentiated liposarcoma, prompting his referral to our surgical unit. Initial chest radiographs revealed a retrocardiac mass (figure 1A). Follow-up arterial phase CT at our institution (figure 2A–C) more clearly demonstrated the transverse colon approaching the diaphragm and its omental attachment streaming through a hiatal defect. The omentum was characterised by several vessels, an important feature of omental hernias, but not lipomas or liposarcomas. Although biopsy was considered, the CT findings obviated any concerns. Paraoesophageal omental hernias are rare and sometimes confused for mediastinal lipomas and liposarcomas, but have important radiological signs that distinguish them from these tumours.^{1 2} Correct diagnosis is important as it can prevent unnecessary and invasive investigations such as angiography, biopsy and thoracotomy.^1–3 On review of the initial CT images, omental vessels, displacement of the transverse colon and a hiatal defect were visible. The patient underwent successful laparoscopic hiatal hernia repair with full resolution of his symptoms. Chest radiography performed 3 weeks postoperatively showed anatomical resolution (figure 1B). We remain sceptical that his hernia was the source of his symptoms, as previous cases reported in literature have been asymptomatic.^1–3

Figure 1.

Chest radiography of a patient with paraoesophageal omental hernia. (A) Preoperatively there is a retrocardiac mass of lipomatous density with no gastric bubble. (B) Postoperatively there is anatomical resolution.

Figure 2.

Arterial phase CT of a patient with paraoesophageal omental hernia in (A) axial, (B) sagittal and (C) coronal planes.

Learning points.

• Paraoesophageal omental hernias are rare and sometimes confused for lipomas and liposarcomas.

• Key radiological findings of omental hernias are omental vessels, superior/posterior displacement of the colon and a hiatal/diaphragmatic defect. Unenhanced CT may only show the latter two features.

• Unnecessary investigations can be avoided with correct diagnosis.