A<unk>   is the protrusion (or herniation) of the upper part of the stomach into the thorax through a tear or weakness in the diaphragm.<unk>  may be classified into four subtypes: type I: Sliding hernia and type II, III, IV: paraesophageal hernias (rolling hernias). It is understood that<unk>  is the result of either decreased elastin of phrenoesophageal membrane due to aging that increases the risk of developing hiatal hernia. Pressure gradient between intra-abdominal and intra-thoracic pressure leads to the esophagogastric junction being displaced into normal<unk> . A rise in intraabdominal pressure and lower thoracic pressure can cause hernia. Esophageal shortening, pulls the junction into the<unk> . This physiological shortening occurs as a normal response to swallowing. The LES is shorter and weaker in large<unk>  and have severe reflux symptoms and trauma. Paraesophageal hernia are less common and have lesser incidence of GERD.<unk>  may be caused by older age, trauma, congenital defects, increase in the abdominal pressure, obesity, and smoking.<unk>  presents as gastroesophageal reflux disease (GERD) with dysphagia and must be differentiated from other causes of dysphagia.<unk> s affect around 1 to 20% of the population. If left untreated, patients with a<unk>  may progress to develop strangulation, esophageal adenocarcinoma, and gastric volvulus. Prognosis is generally excellent and recovery after surgery in a large hernia is approximately 90%. The disease is well controlled with medical therapy but not cured. The symptoms include acid reflux, and pain, similar to heartburn, in the chest and upper stomach. In most patients,<unk> s cause no symptoms. Sometimes patients experience heartburn and regurgitation, when stomach acid refluxes back into the esophagus. Physical examination of patients with<unk>  is usually normal and unhelpful in the diagnosis. On chest radiographs, a paraesophageal hernia may appear as a soft-tissue-opacity lesion posterior to the heart near the esophageal<unk> . CT helps verify migration of the stomach cranially through the<unk> . Sagittal and coronal reformatted images often help demonstrate the hernia and the hiatal defect. Barium swallow may be helpful in the diagnosis of a<unk> . Findings on a barium swallow suggestive<unk>  include anatomy and size of a hernia, the orientation of the stomach location of the gastroesophageal junction. In majority of cases, patients experience no discomfort and no treatment is required. However, when a hiatal hernia is large, it is likely to cause esophageal stricture which results in discomfort. Symptomatic patients benefit from not lying down immediately after meals and also benefit by elevating the head of their beds. If stress has been identified as the major risk factor, stress reduction techniques may be practiced, or if overweight, weight loss may be indicated. Certain medications causes lower esophageal sphincter (or LES to relax those medications should be avoided. Anti-acid drugs like proton pump inhibitors and H2 receptor blockers can be used to decrease the acid secretion. Surgery is the mainstay of treatment for patients with a symptoms or complications. Paraesophageal hernias can be repaired transabdominally or transthoracically. Laparoscopic approach is preferred for most patients. A Nissen-fundoplication is usually done with the surgery. A fixation of the stomach to the abdominal wall (anterior gastropexy) can be used to reduce the risk of gastric reherniation into the thoracic cavity. Complications include pneumonia, pulmonary embolism, heart failure, postoperative leak, and recurrence.
Hiatus hernia
Spigelian hernia
Internal hernia
Incisional hernia
Intussusception
Imperforate anus
Pyloric stenosis
Esophageal cyst