Isolated Gastric Antral Herniation Mimicking Mesenteroaxial Volvulus: The Role of Endoscopy — A Case Report

In a type II paraesophageal hiatal hernia, the gastroesophageal junction (GEJ) remains below the diaphragm while portions of the stomach herniate through the hiatus.The herniated segment is usually the fundus or body, and isolated herniation of the distal stomach is exceptionally rare.A 52-year-old woman with known iron-deficiency anemia presented with sudden, severe epigastric pain.Her hemoglobin level was 8.2 g/dL, her lactate level was normal, and there were no peritoneal signs.Computed tomography revealed the gastric antrum within the thoracic cavity, with the GEJ located below the herniated segment.The appearance of incomplete rotation was interpreted as mesenteroaxial gastric volvulus.Upper gastrointestinal endoscopy identified the GEJ at 38 cm from the incisors, in its normal anatomical position, and approximately 250 mL of semiliquid content was aspirated, decompressing the dilated fundus and body.The endoscope was advanced through the deformed distal body into the intrathoracic antral segment; however, the pyloric channel could not be identified, and repeated maneuvers failed to achieve reduction.The antral mucosa was mildly hyperemic, without ulceration, erosion, or necrosis.Because these findings showed no evidence of strangulation and the patient remained stable, exploration was performed as a planned procedure rather than an emergency intervention after optimization.Exploratory laparotomy confirmed isolated herniation of the antrum within a type II paraesophageal hernia, without gastric torsion.The patient was discharged on the fourth postoperative day and remained asymptomatic at four months.Isolated antral herniation should be included in the differential diagnosis of radiologically suspected gastric volvulus.