Paraseptal emphysema (PSE) is a type of pulmonary emphysema. In PSE, the outermost parts of the lungs fill with enlarged air spaces. This can cause breathing difficulties and other respiratory symptoms.

Currently, there is no cure for PSE or other forms of pulmonary emphysema. However, treatments are available to help slow the progression of the disease, alleviate symptoms, and improve quality of life.

This article describes PSE, including its causes, symptoms, diagnosis, and treatment. We also define mild versus severe PSE and provide information on a person’s outlook.

A doctor holding up a chest x-ray to see signs of paraseptal emphysema.Share on Pinterest
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There are three types of pulmonary emphysema, which differ depending on which part of the lungs it affects. Paraseptal emphysema (PSE) is a type of emphysema, along with centrilobular and panlobular emphysema.

The lungs contain tiny air sacs called alveoli, responsible for exchanging oxygen and carbon dioxide when a person breathes in and out. In emphysema, the alveoli become inflamed and rupture, creating air pockets within the lungs. These air pockets decrease the surface area of the lungs, making the lungs less efficient at exchanging gases.

Different kinds of emphysema affect different parts of the lungs. People with PSE have damage to the alveoli in the outermost parts of their lungs.

There are two main forms of PSE: mild PSE and severe or substantial PSE. Both types involve lucencies, which are areas of lower-density lung tissue.

Scientists define mild PSE as when a person has rows of small lucencies along the outermost parts of their lungs, and each lucency is no larger than 1 centimeter (cm) in diameter. Severe PSE is when lucencies are present in other parts of the lungs, and the lucencies are larger than 1 cm in diameter.

Emphysema occurs when a chronic trigger, such as smoking, causes inflammation in the alveoli within the lungs. The most common cause of emphysema is inhaling cigarette smoke, which could be from smoking or inhaling second-hand smoke.

Other factors that may play a role in the development of emphysema include:

The symptoms of PSE are the same as those for other types of pulmonary emphysema and may include:

These symptoms may worsen as the disease progresses.

The outlook for people with pulmonary emphysema depends on several factors, including:

  • the person’s age and overall health
  • how well the condition responds to medical intervention
  • whether the person experiences complications as a result of the condition

According to a 2021 review, some possible complications of emphysema include:

People with PSE are also at increased risk of developing a collapsed lung. Moreover, evidence also indicates a relationship between cancer and emphysema. Individuals with both PSE and chronic obstructive pulmonary disease (COPD) may be at increased risk of developing certain forms of lung cancer.

As a 2021 review explains, doctors may diagnose PSE using lung function tests and chest X-rays.

A doctor may need to differentiate between the three main types of pulmonary emphysema:

  • Centrilobular (proximal acinar): Affects the more central regions of the lungs.
  • Paraseptal (distal acinar): Affects the outer regions of the lungs.
  • Panlobular (panacinar): Affects all areas of the lungs.

Any of the above types of emphysema have the potential to develop into bullous emphysema (BE). The development of bullae characterizes this type of emphysema, which are air pockets greater than 1 cm in diameter. Large bullae typically cause more severe respiratory symptoms and may require surgical treatment.

Currently, there is no cure for pulmonary emphysema. However, treatments are available to slow the progression of the disease, alleviate symptoms, and improve quality of life. This may involve multiple therapies, such as:

Paraseptal emphysema (PSE) is a type of pulmonary emphysema. There are three main types of pulmonary emphysema. They involve damage to the tiny air sacs or alveoli within the lungs, but each type differs according to the parts of the lungs they affect. Paraseptal emphysema affects alveoli in the outer regions of the lungs.

As with other types of pulmonary emphysema, PSE can cause respiratory issues, such as breathing difficulties, coughing, and wheezing.

Although there is no cure for pulmonary emphysema, treatments can help to slow the progression of the disease and alleviate symptoms. Treatment options include anti-inflammatory medications to reduce airway inflammation, bronchodilators to ease breathing, and opioids to help with pain management. A person can consult their doctor about their individual treatment options and outlook.