Intraocular Pressure in Laparoscopic Inguinal Hernia Repair

Inguinal hernia is a common clinical condition, accounting for approximately 75% of abdominal wall hernias. It is more common in men than women, affecting approximately 25% of men and 2% of women throughout their lifetime. Due to its frequent occurrence, inguinal hernia surgery is one of the most common operations worldwide. The incidence of inguinal hernia shows a bimodal distribution, with the highest incidence occurring around the age of 5 and over 70. Two-thirds of these hernias are indirect hernias.

Many previous studies have identified several risk factors in its etiology, including advanced age, male gender, smoking, family history, conditions causing intra-abdominal pressure, and collagen connective tissue diseases.

The most fundamental point in diagnosing inguinal hernia is physical examination. Physical examination is the easiest and most accurate way to diagnose the hernia. However, while most inguinal hernias are diagnosed by physical examination, radiological examination may be necessary in cases where the body structure prevents physical examination. Radiological methods include ultrasonography, computed tomography and rarely magnetic resonance imaging.

The primary treatment for inguinal hernia is surgical options. In addition to the standard open surgical approach, the Lichtenstein technique, laparoscopic methods such as transabdominal preperitoneal (TAPP) and total extraperitoneal (TEP) approaches are currently the most commonly used surgical procedures.

The most frequently used laparoscopic treatment methods worldwide are TAPP and TEP procedures. In both methods, mesh is placed in the preperitoneal space, but in the TAPP technique, it is necessary to enter the abdominal cavity to place the mesh. In the TEP procedure, all procedures are performed without opening the peritoneal wall and without entering the abdomen.

While it is debated whether one procedure is superior to the other, there are discussions about their relative advantages and disadvantages. The most important advantage of the TEP procedure is that it is performed without entering the abdominal cavity; its disadvantage is that the surgeon performing the operation has to work in a narrower area. The advantages of the TAPP procedure are that it is a simpler technique, has a wider working area, and is suitable for bilateral evaluation. The disadvantage is the higher risk of intra-abdominal organ injury and intra-abdominal adhesions.

Both methods result in less postoperative pain, seroma, chronic pain, hematoma, and wound infection compared to the Lichtenstein technique.

Many surgeons use the Trendelenburg position, approximately 30 to 45 degrees, when performing laparoscopic procedures. The advantage of the Trendelenburg position is that it allows for better visualization of the abdominal and pelvic organs and creates space for the operation. However, the Trendelenburg position also has some complications, such as increasing intraocular pressure.

Also, in laparoscopic surgeries, pneumoperitoneum is created by introducing CO₂ gas into the abdomen. This increases intra-abdominal pressure, causing the diaphragm to be pushed upward and raising thoracic pressure. As a result, central venous pressure increases and intracranial venous return becomes difficult, which can lead to a temporary increase in intraocular pressure.

When the patient is placed in a head-down position, this return becomes even more difficult, and intraocular venous pressure increases even more. Similarly, prolonged surgery time can lead to increased hypoventilation and hypercapnia, which can cause choroidal congestion and increase intraocular pressure.

Perioorbital swelling and venous congestion caused by prolonged surgery time and the position used can cause compartment syndrome in the orbital space and even lead to vision loss.

The current literature indicates that the increase in intra-abdominal pressure during laparoscopic surgery, the patient's position, and the surgery time can lead to an increase in intraocular pressure.

Inclusion criteria

• Being over 18 years of age
• Having been diagnosed with inguinal hernia
• Those wishing to participate in the study

Exclusion criteria

• Patients under 18 years of age
• Patients diagnosed with glaucoma
• Patients with rheumatological diseases (rheumatoid arthritis, SLE, etc.)
• Patients with chronic kidney and liver failure
• Patients who have undergone corneal transplantation
• Patients with malignancy
• Patients diagnosed with bilateral inguinal hernia
• Patients with ocular trauma
• Myopia or hyperopia exceeding three diopters
• Patients using systemic steroids
• Body Mass Index > 30 kg/m2
• Those who do not wish to participate in the study