What is Parahiatal Hernia?
A Parahiatal hernia is a rare condition in which certain organs in your belly push through an abnormal opening in the diaphragm, the muscle that aids in breathing and separates your chest from your abdomen. This usually happens between the left parts of the right and left sections of your diaphragm. The diaphragm usually has standard openings for various structures, but in this case, the opening is abnormal. The hiatal opening, located in line with the 10th bone in your spine, allows the food pipe (esophagus) to travel through the right part of the diaphragm to connect with the stomach. This forms an area called the gastroesophageal junction. A Parahiatal hernia usually happens on the left side of this junction.
It can be confusing to tell the difference between a Parahiatal hernia and a Hiatus hernia because they are so similar in location.
A Hiatus hernia is a more common type of hernia that affects the diaphragm. There are different types of Hiatus hernias. The most common is the “sliding type,” where the gastroesophageal junction moves upwards. A less common is the “paraoesophageal type,” where the stomach rolls without movement of the gastroesophageal junction, or it can roll while the gastroesophageal junction migrates. In the most severe case of diaphragmatic hernia, other abdominal organs in addition to the stomach move upwards into the chest. The distinguishing feature of a Hiatus hernia is that the organs push through a normal opening in the diaphragm instead of an abnormal one, which is what happens in a Parahiatal hernia. Usually, the only organ that gets displaced in a Hiatus hernia is the stomach, but in rare cases, it can include others such as the transverse colon, omentum, small intestine, and spleen.
What Causes Parahiatal Hernia?
The details on PHH aren’t very clear in medical literature, but we do know that, like other types of diaphragmatic hernias, PHH can be something a person is born with (congenital) or something they develop later in life (acquired).
Among congenital diaphragmatic defects, the two most common are the Bochdalek hernia and the Morgagni hernia. The Bochdalek hernia is a defect located towards the back and side that happens when certain folds in the diaphragm don’t close correctly during development. The Morgagni hernia is a defect towards the front and middle that occurs when various parts of the diaphragm don’t join together as they should. Both of these conditions usually happen on the left side of the body.
Acquired diaphragmatic defects, on the other hand, can happen due to trauma, after esophageal surgery, or when the diaphragm muscle progressively weakens.
According to the evidence we do have about diaphragmatic hernias, congenital PHH seems to be a defect located in the back and middle of the diaphragm, which happens when a specific part of the diaphragm known as the dorsal mesentery doesn’t develop properly.
Risk Factors and Frequency for Parahiatal Hernia
Parahiatal hernia (PHH) cases are often discovered by accident and are usually documented in individual case reports. As such, getting an exact figure of how often this type of hernia occurs is tricky. However, estimates suggest that between 0.2% and 0.35% of individuals could have a Parahiatal hernia. This condition commonly turns up in older people and occurs in both males and females equally.
Signs and Symptoms of Parahiatal Hernia
Parahiatal Hernia (PHH) is a condition that may present symptoms similar to other diaphragmatic hernias, making it a challenge to differentiate it from the more common paraesophageal hernias. Patients with PHH typically do not experience symptoms of acid reflux, unless a hiatal hernia is also present. Identifying these conditions separately is crucial because it impacts the method of treatment and the overall patient outcomes.
These defects are often discovered unexpectedly during other medical check-ups or while repairing a hiatal hernia. Some case studies in medical literature have reported urgent cases involving either intestinal entrapment or a twisted intestine (volvulus).
Patients with PHH may experience:
- Discomfort in the upper belly area
- Nausea
- Vomiting
- Chest pain after eating, similar to angina
- Feeling full early in your meal
- In severe cases, breathing problems
Patients may show signs of anemia due to stomach erosion at the neck of the hernia, mild discomfort in the upper belly, and reduced breath sounds in the left lower chest area.
Testing for Parahiatal Hernia
A chest X-ray can be helpful in examining sizable defects related to peritoneal hiatal hernia (PHH), which is a type of diaphragmatic hernia (a condition where an organ moves into an unusual position due to a hole in the diaphragm). Signs of this could be an air-fluid level, which is a classic sign of diaphragmatic hernia, along with the appearance of small or large bowel loops filled with gas.
Further, a procedure called an “Esophagogastroscopy on J-maneuver” can help visualize the abnormal opening caused by the PHH alongside the normal esophageal opening. This aids in distinguishing PHH from a standard hiatal hernia. However, at times, PHH may look like a gastric diverticulum (a small pouch in the stomach) during this procedure.
A contrast swallow study is another diagnostic tool that can help identify other esophageal disorders that may co-exist, such as achalasia (a condition affecting food passage through the esophagus) or gastroesophageal reflux disease (GERD), and it can confirm the presence of a diaphragmatic hernia. However, this test alone cannot definitively identify PHH.
In order to reach a more certain diagnosis, and to assess the severity of any reflux disease, your doctor may recommend manometry and pH studies. These tests measure the esophagus’s performance and the level of acid in the esophagus, respectively. The gathered data can then guide your surgeon toward the most appropriate type of repair. However, the final decision will heavily rely on your health history and the findings during any emergency surgery.
In most cases, a Computed Tomography (CT) scan of the chest and upper abdomen with 3-dimensional views is the most favored test since it can offer the most precise depiction of the diaphragmatic hernia’s anatomy. This test is beneficial in recognizing the distinguishing features of PHH.
Treatment Options for Parahiatal Hernia
Paraesophageal hiatal hernia (PHH), a condition where part of your stomach pushes through the diaphragm into the chest, can be managed in two ways, depending on how it presents. These are either with conservative (non-surgical) treatment or surgery.
If PHH does not cause symptoms or problems (dormant), it can sometimes be managed with non-surgical treatments. However, these treatments are not recommended when there are complications such as the stomach twisting on itself (gastric volvulus).
Surgery is the recommended approach for larger PHH or those causing symptoms. The operation aims to get the stomach back in its normal position, remove the hernia sac, and seal the hole that permitted the hernia to develop. This is typically done with a laparoscopic approach, which is minimally invasive surgery using small incisions. If the hole is large or the tissue is weak, reinforcement, like a mesh, may be used to strengthen the area. A special absorbable mesh is usually preferred for this purpose.
An additional procedure to prevent acid reflux, where stomach acid backs up into the esophagus (the tube connecting the mouth to the stomach), may be needed if you have reflux symptoms or when the part of the body where the stomach and esophagus meet (the gastroesophageal junction or GEJ) is disturbed.
The risk of complications or recurrence of hernia or acid reflux may increase if an anti-reflux procedure is not performed during the hernia operation. However, there might be a reduced risk of difficulty swallowing (dysphagia). Whether an anti-reflux procedure is performed or not often depends on individual situations. Generally, a procedure called partial Toupet fundoplication is performed, but it may vary depending on the surgeon’s preference and specialty.
The European Association of Endoscopic Surgery created guidelines on how to manage PHH. These guidelines heavily lean towards surgery in most adults with moderate to large PHH, even those without symptoms, over non-surgical treatment. However, they suggest non-surgical treatment is advisable for frail patients with little or no symptoms. They also recommend using mesh for hiatal closure, favoring an anti-reflux procedure over a stomach anchoring procedure (gastropexy) during elective surgery. On the other hand, in emergency situations with patients having heart or lung instability, they suggest a gastropexy might be favorable over an anti-reflux procedure. However, remember these recommendations depend on individual situations and require a joint decision between the doctor and the patient.
What else can Parahiatal Hernia be?
When doctors try to diagnose a condition called PHH, they need to ensure it’s not actually one of the following ailments, which can resemble PHH:
- Type III or IV Paraesophageal hiatus hernia
- Traumatic diaphragmatic hernia
- Gastric diverticulum
- Acute coronary event
- Acute pancreatitis
To figure out the correct diagnosis, doctors will conduct a thorough examination of the patient and may use various imaging techniques.
What to expect with Parahiatal Hernia
The general outlook for PHH, or Pseudomyxoma Hepatis, is hard to determine. This is because not many people are aware of it and there have only been a few cases reported in medical literature. According to the few studies that have been published on it, PHH usually has a good outcome if treated quickly, and there are no significant health complications or deaths reported after surgery. Only one study reported a case where the condition came back after treatment out of 8 patients.
Possible Complications When Diagnosed with Parahiatal Hernia
Before surgery, PHH (paraesophageal hernia) often doesn’t come to doctors’ attention until patients start experiencing symptoms when it’s large. It can cause the stomach to twist and trap in the chest (gastric volvulus) and lead to ischemia and bowel obstruction, depending on the contents of the hernia. It’s important to diagnose it early to prevent damage and death (necrosis) to part of the stomach (gastric fundus).
During the surgery, it’s not rare for surgeons to accidentally harm the pleura, the tissue that wraps around your lungs and chest cavity, causing air around the heart (pneumothorax). But usually, it heals within 24 hours without causing any more problems. High-pressure pneumothorax (tension pneumothorax) is much rarer, happening in 1-2% of cases. Major bleeding is also rare, with incidents occurring in 2% of cases. Then we have damages to the stomach and esophagus are even rare, seen in only 1% of cases. After removing the hernia, the space created inside the chest cavity usually gets filled up by the lungs but can sometimes develop a fluid collection (seroma). If the sac isn’t completely removed, there’s a higher risk of this fluid getting infected. If the fluid collection isn’t infected, doctors usually just keep an eye on it without doing anything. But if it’s infected, radiologists may need to drain it, and the patient will need appropriate antibiotics.
Common Side Effects:
- Gastric volvulus (stomach getting twisted and trapped)
- Ischemia (tissues not getting enough blood)
- Bowel obstruction
- Necrosis of the gastric fundus (death of part of the stomach)
- Pneumothorax (air around the heart)
- Tension pneumothorax
- Major bleeding
- Damage to the stomach and esophagus
- Fluid collection in the chest cavity
- Infection
Recovery from Parahiatal Hernia
The post-surgery care for PHH, or partial hepatic hemangioma, is focused on the concept of enhancing recovery. Patients start moving around shortly after surgery, begin drinking fluids as soon as possible, and receive suitable pain relief. Typically, if the patient hasn’t had an anti-reflux procedure, they can start a soft diet soon after surgery. If they have had the procedure, their diet will be slowly increased over the following two weeks.
Preventing Parahiatal Hernia
A paraesophageal hiatal hernia (PHH) is a medical condition where internal body organs bulge unusually through an abnormal opening between the left part of two muscle-like structures in the chest, called right and left crura of the diaphragm. By contrast, a hiatal hernia occurs when these organs bulge through the normal opening in the right muscle-like structure or crus.
It’s important to know that PHH does not always require a procedure known as an antireflux procedure, unless it’s accompanied by gastroesophageal reflux disease (a condition that causes stomach acid to flow back into the tube that connects your mouth and stomach) or a hiatal hernia.
Doctors need to stay alert especially with high-risk patients. After ruling out immediate life-threatening situations, they should consider the chance of a diaphragmatic hernia (a hole in the diaphragm, the muscle separating the chest from the abdomen), which allows abdominal organs to move into the chest).
