TürkçePleural fibrosis is a chronic condition characterized by thickening of the pleural membrane surrounding the lungs and loss of its elasticity. This condition restricts lung expansion, leading to reduced respiratory capacity. It usually develops following inflammation, infection, or asbestos exposure and may show a progressive course.
Symptoms of pleural fibrosis arise from restricted lung function and most commonly present as shortness of breath that worsens with exertion. Chest pain, a dry cough, and a sensation of stiffness in the chest wall may accompany it. In advanced cases, a marked reduction in lung volume is observed, increasing the risk of respiratory failure.
The causes of pleural fibrosis include previous pleural infections, tuberculosis, hemothorax, and surgical procedures. In particular, asbestos exposure is an important risk factor. Chronic inflammatory processes increase fibrotic tissue within the pleural layers, resulting in permanent structural changes.
Treatment of pleural fibrosis is planned according to the underlying cause and the rate of disease progression. Observation may be sufficient in mild cases, while surgical decortication may be considered in advanced cases. Pulmonary rehabilitation and supportive therapies play an important role in improving quality of life.
How Does the Pleural Membrane Function in a Healthy Person and How Does the Process of Pleural Fibrosis Begin?
Inside the chest cavity of a healthy person lies a remarkable anatomical structure with a perfectly functioning system. A very thin, double-layered membrane surrounds the outer surface of the lungs, the inner wall of the chest cavity, and the central space where the heart is located. This membrane is called the pleura. The inner layer closely covers the lungs, extending into every groove and fissure. The outer layer adheres to the inner surface of the chest wall and the diaphragm muscle.
Between these two delicate membrane layers is a microscopic space that is almost impossible to see with the naked eye. Within this narrow space is a very small amount of specialized fluid that is continuously produced and reabsorbed. The sole purpose of this fluid is to prevent friction between the lungs and the chest wall as the lungs expand and contract with every breath. Just as a few drops of water placed between two sheets of glass allow them to slide smoothly over each other, this fluid serves as the perfect lubricant for normal lung function.
However, once this delicate balance is disrupted, the process of pleural fibrosis is triggered. Various diseases cause much more fluid than normal to accumulate between the pleural layers. Over time, this fluid becomes inflamed, and sticky clotting proteins known as fibrin begin to accumulate within it. The small channels and lymphatic vessels normally responsible for clearing excess fluid become blocked by these sticky proteins. The fluid that can no longer be removed gradually thickens, solidifies, and settles onto the pleural surface. The normally flexible tissue is slowly invaded by connective tissue cells, transforming into a thick, rigid, non-elastic shell. The lung then becomes trapped within this shell.
What Are the Main Causes Leading to the Development of Pleural Fibrosis (Pleural Thickening)?
Identifying the true underlying cause of pleural thickening is the most important step in planning the treatment pathway that will restore the patient’s health. Extensive investigations in the fields of pulmonology and thoracic surgery have shown that this condition is most commonly associated with unresolved infections.
According to data from our country, the principal etiological factors responsible for this condition include:
- Nonspecific infections
- Tuberculosis
- Bacterial pneumonia
- Sharp object injuries
- Penetrating injuries
- Postoperative infections
- Gunshot wounds
- Malignant mesothelioma
How Can Untreated Pneumonia Progress to Pleural Fibrosis?
Common illnesses such as pneumonia caused by bacterial infection or exposure to cold should never be underestimated. Depending on the severity of the infection, these lung diseases may cause fluid to accumulate around the pleura. If the patient’s symptoms are ignored and this fluid is not recognized and drained early using appropriate medical methods, the condition may rapidly worsen. Initially clear and free-flowing, the fluid soon becomes infected as microorganisms multiply, progressing into a dangerous collection of pus known as empyema.
This process does not occur suddenly but progresses through distinct stages. In the first stage, the fluid remains relatively thin and is comparatively easy to manage. However, over time it becomes thicker, with clots and sticky strands forming that bind the pleural layers together. If proper treatment is still not provided at this stage, the condition advances to the organized phase. The infected fluid solidifies completely, forming a thick, leather-like shell around the lung. At this point, neither antibiotics alone nor simple needle drainage can successfully resolve the condition.
How Does Tuberculosis Trigger the Development of Pleural Fibrosis?
Tuberculosis is one of the most challenging causes of pleural disease. When the tuberculosis bacterium reaches the pleural membrane, the body’s immune system mounts an extremely intense and destructive response. This creates a severe inflammatory reaction between the pleural layers.
Even in patients who adhere to their tuberculosis treatment, permanent pleural thickening or damage may still be observed months after therapy begins. Tuberculous empyema follows an even more severe course. The inflammation between the pleural layers becomes chronic, and calcifications, often described as “stone-like” changes, develop over time. These calcified, inflamed areas containing high concentrations of tuberculosis bacteria may occasionally create abnormal air passages (fistulas) between the lung and the pleural cavity, making treatment considerably more complex.
What Symptoms Are Seen in Patients with Pleural Fibrosis and What Are Its Physical Effects?
Pleural fibrosis does not develop overnight. In most cases, it progresses slowly and insidiously. Although patients may initially pay little attention to their symptoms, daily activities gradually become increasingly restricted. The most prominent complaint is shortness of breath during physical activity, which eventually may occur even at rest. Patients may also experience a dull, persistent chest pain that does not significantly change with breathing. This pain results from continuous pressure exerted by the thickened, hardened tissue against the inner chest wall and the nerves beneath the ribs.
The main physical examination findings include:
- Reduced breath sounds
- Absent breath sounds
- Dullness to percussion
- Reduced tactile fremitus
- Narrowing of the chest wall
- Tracheal deviation
- Asymmetrical chest movements during breathing
As the disease becomes chronic, the thickened pleura may create such a strong inward pulling force that a visible depression develops on the affected side of the chest. As the lung decreases in volume, the trachea may also shift from the healthy side toward the diseased side.
How Is Pleural Fibrosis Diagnosed Using Modern Imaging Techniques?
After the patient’s symptoms have been evaluated and a clinical examination completed, imaging technologies are used to determine the extent of internal damage. Although a standard chest X-ray provides initial clues, much more advanced imaging techniques are required to accurately evaluate millimeter-scale pleural thickening, trapped pleural fluid, and possible calcifications.
Why Are CT Scans and Pulmonary Function Tests Essential Before Pleural Fibrosis Surgery?
Computed tomography has become an indispensable guide for diagnosing pleural fibrosis and especially for surgical planning. Contrast-enhanced CT scans provide a three-dimensional map of the chest cavity.
One of the most important CT findings is the split pleura sign. This imaging feature clearly demonstrates that organized infected fluid remains trapped between the thickened inner and outer pleural layers. CT also helps distinguish whether pleural thickening results from a simple infection or from more serious conditions such as asbestos exposure or cancer.
Pulmonary function tests objectively measure how much the disease has reduced lung capacity. Because pleural fibrosis prevents the lungs from expanding normally, it produces a restrictive pattern of lung disease.
The pulmonary function parameters measured most carefully include:
- Forced vital capacity
- Forced expiratory volume in one second
- Maximum voluntary ventilation
- Vital capacity
These test results not only determine the patient’s lung capacity before surgery but also provide an objective way to monitor recovery after treatment.
When Should Surgical Intervention (Decortication) Be Performed for Pleural Fibrosis?
The surgical removal of the rigid fibrous shell surrounding the lung is known as decortication. This procedure is far more complex than simply draining fluid from the pleural cavity. Decortication involves meticulously peeling away the diseased fibrous tissue tightly attached to the lung surface while preserving the healthy lung beneath. It can be compared to carefully peeling the thick skin from an orange without damaging the fruit inside.
Timing is critically important. The ideal time for intervention is during the stage when the fluid has begun to organize but before irreversible damage has occurred within the lung tissue itself. If fluid accumulation persists despite months of medical therapy and much of the lung remains compressed, surgery should be considered. Particularly in infected cases, prolonged reliance on antibiotics alone after diagnosis allows the disease to organize further, making surgery more difficult and prolonging hospitalization.
What Are the Benefits of Minimally Invasive Surgery for Pleural Fibrosis?
In the past, open surgery requiring large incisions between the ribs was the standard approach for removing the thickened pleural membrane. Today, however, minimally invasive techniques have transformed treatment. In Video-Assisted Thoracoscopic Surgery (VATS), only a few small incisions measuring a few centimeters are made in the chest wall. High-definition cameras and long surgical instruments are inserted through these openings, allowing the operation to be performed while viewing a monitor.
The greatest advantage of this minimally invasive approach is that the ribs do not need to be forcibly spread apart using surgical retractors. Rib spreading can compress the nerves running beneath the ribs, resulting in severe chronic pain that may last for months. This risk is minimized with minimally invasive surgery.
The main advantages of VATS include:
- Very low pain levels
- Low infection risk
- Rapid recovery
- Short hospital stay
- Early chest drain removal
- Preservation of the immune system
- Preservation of respiratory muscles
- Small cosmetic scars
Although minimally invasive surgery offers many benefits, some exceptional situations still require conversion to traditional open surgery to ensure patient safety, particularly when the disease is very advanced, the pleura has become heavily calcified, or extremely dense adhesions are present.
Which Additional Surgical Procedures Are Used in Advanced Cases of Pleural Fibrosis?
In very advanced tuberculosis cases or when lung tissue has suffered irreversible damage, simply removing the fibrous pleura may not provide an adequate solution. Even after decortication, the lung may be too damaged to re-expand and fill the chest cavity. If this remaining space fills with air, it creates an ideal environment for recurrent infection.
In such difficult situations, additional procedures are used to eliminate this dead space. In patients too weak to tolerate major surgery, a small permanent opening may be created in the chest wall to allow continuous drainage of infected material. Although this approach does not completely eliminate the disease, it serves as an effective palliative treatment by preventing systemic infection. Another option involves using the patient’s own muscle tissue to fill the space that the lung can no longer occupy.
What Steps Are Followed During Recovery After Pleural Fibrosis Surgery?
Decortication is a technically demanding and delicate procedure. While removing the thick fibrous shell that has adhered to the lung for years, tiny abrasions naturally develop on the outer surface of the lung. These microscopic injuries may allow small amounts of air to leak as the patient breathes after surgery.
Managing this situation is a routine part of postoperative thoracic surgical care. Thin chest tubes placed during surgery drain accumulated fluid and escaping air into a specialized underwater drainage system. If the air leak lasts longer than expected, gentle suction can be applied to the drainage system, helping the lung gradually adhere to the chest wall and allowing the leak to seal.
In some patients, particularly those unsuitable for surgery or before an operation, special medications may be administered through these chest tubes into the pleural cavity. The primary goal is to dissolve the organized material within the pleural space.
The main fibrinolytic agents used include:
- Urokinase
- Streptokinase
- Tissue plasminogen activator
These medications liquefy the clots, fibrous membranes, and organized infected material, allowing them to drain much more easily through the chest tube. Patients are periodically repositioned onto their sides or forward in bed to help the medication reach every area within the pleural cavity.
How Does Pleural Fibrosis Surgery Affect Patients’ Quality of Life?
The primary goal of pleural surgery is not only to eliminate infection but also to restore the patient’s ability to breathe freely. Following a successful operation, patients typically experience a clear and noticeable improvement in breathing capacity.
Follow-up chest X-rays and CT scans demonstrate complete removal of the thick diseased pleura, while the previously shrunken lung expands once again to fill the chest cavity. Pulmonary function test values improve steadily over the following months, approaching normal levels. Patients are no longer troubled by the debilitating shortness of breath that previously occurred while climbing stairs, walking, or performing daily activities.
Of course, surgical success alone is not sufficient. Postoperative breathing exercises and chest physiotherapy are essential for restoring normal lung flexibility. When intervention is performed early, before permanent damage develops, and followed by appropriate rehabilitation, patients can overcome restrictive breathing limitations and return to normal life with comfortable, unrestricted breathing. Recovery is particularly rapid and complete in younger individuals and children due to their greater regenerative capacity.
Frequently Asked Questions
Prof. Dr. Alper Fındıkcıoğlu graduated from Istanbul University Faculty of Medicine and completed his thoracic surgery residency at Dr. Siyami Ersek Hospital. He began his academic career at Başkent University in 2005; he received the title of associate professor in 2014 and professor in 2022. He has extensive experience in lung cancer, chest wall diseases, and minimally invasive surgery. Since 2024, he has been continuing his professional work at Acıbadem Hospital.
