# True Diaphragmatic Hernia (Morgagni Hernia) Incidentally Diagnosed with Positive Contrast Peritoneography in a Cat: A Rare Case Report and a Review

## TL;DR

A cat with a rare Morgagni hernia was diagnosed using contrast peritoneography and successfully treated surgically.

## Contribution

This case highlights the diagnostic value of peritoneography in identifying rare congenital diaphragmatic hernias in cats.

## Key findings

- Contrast peritoneography confirmed a congenital pleuroperitoneal hernia in a cat.
- The hernia was analogous to the human Morgagni hernia, located ventrally and to the right.
- The cat fully recovered after surgical repair of the diaphragmatic defect.

## Abstract

An 18-month-old domestic shorthair cat survived a fall from the second floor with minor injuries and no breathing issues. Routine radiographs suggested an unusual diaphragmatic hernia, which, contrast peritoneography revealed to be a pleuroperitoneal hernia—a congenital defect. This was confirmed and surgically repaired during laparotomy. The cat fully recovered. This case emphasizes the diagnostic value of peritoneography for hernias. The diaphragmatic defect, being ventral and to the right, corresponds to the right anterolateral hernia found in humans, known as “Morgagni hernia”.

An 18-month-old neutered male domestic shorthair cat was presented for an emergency consultation after falling from the second floor. The cat sustained minor traumatic injuries but did not exhibit dyspnea. Routine radiographic examination raised suspicion of a diaphragmatic hernia, but the circumscribed nature of the soft tissues visible in the thorax was atypical for a classic traumatic diaphragmatic hernia. A positive contrast peritoneography highlighted the likely presence of a hernial sac, which strongly suggested a “true diaphragmatic hernia”, also known as “pleuroperitoneal hernia”. This diagnosis was confirmed during laparotomy, which allowed for the visualization of a 3 cm radial diaphragmatic defect in the right ventral quadrant of the pars sternalis. The diaphragm’s edges were rounded. A portion of the falciform ligament and a part of the omentum were protruding through the defect and were contained within a hernial sac. Herniorrhaphy was performed. The cat recovered without complications. Given its presentation and location, ventrally and to the right, this anomaly is analogous to what is described in humans as “Morgagni hernia”. Six other cases of Morgagni hernias have probably been reported in cats but were not identified as such. This case underscores the utility of peritoneography, a straightforward technique useful for diagnosing diaphragmatic hernias, which enables differentiation between acquired traumatic forms and congenital forms, particularly peritoneopericardial hernias and pleuroperitoneal hernias. True diaphragmatic hernias are almost always serendipitous discoveries.