BACKGROUND
Morgagni hernias are a rare subtype of congenital diaphragmatic hernia, representing only 2% to 4% of all cases. In adults, they are most commonly diagnosed in middle or later life and show a female predominance. Adult patients may remain asymptomatic and receive an incidental diagnosis; however, surgical repair is generally considered due to the potential risks of incarceration, obstruction, and strangulation. Laparoscopic surgery has emerged as a minimally invasive treatment option. Cases involving this combination of features, including an asymptomatic young adult man with obesity and a large defect, have rarely been reported.
CASE REPORT
We report the case of an 18-year-old asymptomatic man with class II obesity (body mass index, 36.7 kg/m²) who was incidentally diagnosed with a large Morgagni hernia during a routine health examination. Chest and abdominal computed tomography (CT) revealed a diaphragmatic defect measuring up to 6.9 cm in diameter; a large hernia sac protruded into the thoracic cavity. To prevent future complications, laparoscopic repair with composite mesh reinforcement and preservation of the hernia sac was successfully performed. The postoperative course was uneventful. On postoperative day 4, chest CT showed a small localized fluid collection in the region of the residual hernia sac. Because the patient remained asymptomatic, conservative observation was implemented. No recurrence was detected during 1 year of follow-up.
CONCLUSIONS
This case suggests that a large asymptomatic Morgagni hernia in a patient with class II obesity can be safely treated by laparoscopic repair with primary defect closure, composite mesh reinforcement, and preservation of the hernia sac.

Keywords: Case Reports; Hernia, Diaphragmatic; Laparoscopy; Obesity