What Are Kerley Lines?

Kerley lines are radiographic findings consistent with fluid in the interstitial tissue of the lungs. They are divided into several types based on their visual appearance, which can provide more information on their origins and nature. Patients with Kerley lines may have a number of different conditions, but congestive heart failure is a common cause. During treatment for the disease that caused the fluid buildup, follow-up x-rays can indicate whether the patient’s lungs are healing in response to therapy.

Doctors may request chest x-rays for patients with suspected lung or heart disease to gather data on conditions inside the chest and establish a reference to use in follow-up visits. People with certain parasites or conditions such as pulmonary fibrosis and some cancers can develop pulmonary edema, where fluid gathers in and around the lungs. The interstitium contains blood vessels and small sacs known as alveoli that exchange carbon dioxide for oxygen. When fluid builds up in this region, patients may struggle to breathe, the level of oxygen in the blood can drop, and Kerley lines develop.

In patients with Kerley lines, the x-ray will have a fine threading of opaque lines, indicating that fluid is present. Kerley A lines are long and typically do not branch. B and C lines are shorter, with B lines tending to take on a parallel, ladder-like appearance. A radiologist can review the film and discuss the findings with the patient. Other issues may be visible on the x-ray as well, such as pockets of fluid created by disease.

Chronic irritation and inflammation in the lungs can lead to scarring, which will decrease overall lung function. If a patient has Kerley lines and other traces of lung disease, it may be necessary to perform a spirometry study. In this testing, a technician guides the patient through a series of breathing exercises with equipment to measure lung capacity and other characteristics. This can provide information about the patient’s level of function and also creates a baseline to use in follow-up studies that may determine whether the patient’s lung function is improving.

Treatment options for a patient with Kerley lines depend on the cause. Medications may help manage issues like parasites and cancers. Some patients need diet and lifestyle modifications. Severe organ damage may qualify a patient for a transplant to replace failing organs that may be contributing to edema and other problems. Careful monitoring throughout treatment can identify early signs of complications such as secondary illnesses or bad reactions to medications.