Dr. David Midthun of Pulmonary and Critical Care Medicine at the Mayo Clinic states that noncancerous lung nodules commonly occur due to a prior fungal infection, a bacterial infection, a mycobacterial infection or a benign tumor. A solitary lung nodule sometimes indicates an early cancer.Know More
Dr. Midthun explains that lung nodules are common and usually noncancerous. They are typically scars that result from a prior infection, such as histoplasmosis or coccidiodomycosis. A CT scan of the chest reveals one or more tiny nodules in many cases. These nodules look white because they are denser than the surrounding lung, which contains air and appears darker. Smaller nodules are mostly noncancerous, particularly those that are less than 5 millimeters in size. However, larger nodules that measure more than 20 millimeters have more than a 50 percent chance of being cancerous.
When a solitary lung nodule is detected, doctors typically consider other factors that affect the probability of the nodule being cancerous, notes Dr. Midthun. Smokers have a higher risk of lung cancer. People older than 50 are also more likely to have a malignant nodule. Moreover, a family history of lung cancer and asbestos exposure both present an increased risk factor. The nodule is most likely noncancerous if there is no change in size, shape or appearance after comparing the patient's current X-ray or CT scan with a previous one.Learn more about Organs
New Health Guide explains that white spots on toenails can be caused by injury, allergic reaction, zinc deficiency, calcium deficiency, fungal infection or illness. In most cases, white spots, also called leukonychia, are not a cause for concern. However, if the spots appear frequently or in patterns, MDhealth.com warns that medical attention is necessary to track down the exact cause.Full Answer >
Terminal bronchioles are the air passages into the lungs. They branch into respiratory bronchioles and secrete a nonsticky surfactant to maintain the airway. Surfactant is a proteinaceous compound that maintains the airway in the smallest bronchioles and alveoli by keeping surface tension during inspiration and keeping them from collapsing during expiration.Full Answer >
The variances in predicted vital capacity as related to height has to do with the size of the lungs and amount of room for the diaphragm to expand inside the body. Height is only one factor that is calculated into the vital capacity measurements.Full Answer >
Bronchioles are tiny airways that carry oxygen to alveoli, or air sacs, in the lungs and help stabilize breathing in the respiratory system, according to About.com. Bronchioles are lined with smooth muscular walls that constrict or expand to regulate airflow and prevent irritants from passing further along the respiratory tract.Full Answer >