There are three types bronchiectasis that can be seen on CT scan, namely cylindrical, varicose, and cystic bronchiectasis. Prevention
In preventing bronchiectasis, it is necessary to prevent the lung infections and lung damage that can cause it. Children should be immunized against measles, pertussis, pneumonia, and other acute respiratory infections of childhood. Additionally, parents should stay alert to keep children from inhaling objects such as pieces of food or small toys that may get stuck in small airways. Smoking and other toxic fumes and gases should be avoided by all patients with bronchiectasis to decrease the development of infections (such as bronchitis) and further complications.Treatments to slow down the progression of this chronic disease include keeping bronchial airways clear and secretions weakened through various forms of airway clearance. Aggressively treating bronchial infections with antibiotics to prevent the destructive cycle of infection, damage to bronchi and bronchioles, and more infection is also standard treatment. Regular vaccination against pneumonia, influenza, and pertussis are generally advised. A healthy body mass index and regular doctor visits may have beneficial effects on the prevention of progressing bronchiectasis. The presence of hypoxemia, hypercapnia, dyspnea level and radiographic extent can greatly affect the mortality rate from this disease. Management
A comprehensive approach to the management of bronchiectasis is recommended. It is important to establish whether an underlying modifiable cause, such as immunoglobulin deficiency or alpha-1 antitrypsin deficiency is present. The next steps include controlling infections and bronchial secretions, relieving airway obstructions, removing affected portions of lung by surgery, and preventing complications.
The medication has low but significant affinity for human serum sex hormone-binding globulin (SHBG), about 25% of that of testosterone and 5% of that of DHT. Metabolism
The biological half-life of methyltestosterone is approximately 3 hours (range 2.5–3.5 hours). The duration of action of methyltestosterone is said to be 1 to 3 days, and is described as relatively short among AAS. Excretion
Methyltestosterone is excreted 90% in the urine as conjugates and other metabolites, and 6% in feces. Chemistry
Methyltestosterone, also known as 17α-methyltestosterone or as 17α-methylandrost-4-en-17β-ol-3-one, is a synthetic, 17α-alkylated androstane steroid and a derivative of testosterone differing from it only in the presence of a methyl group at the C17α position. Close synthetic relatives of methyltestosterone include metandienone (17α-methyl-δ1-testosterone) and fluoxymesterone (9α-fluoro-11β-hydroxy-17α-methyltestosterone). Derivatives
Methyltestosterone and ethyltestosterone (17α-ethyltestosterone) are the parent structures of all 17α-alkylated AAS. Major 17α-alkylated AAS include the testosterone derivatives fluoxymesterone, metandienone (methandrostenolone), and methyltestosterone and the DHT derivatives oxandrolone, oxymetholone, and stanozolol. Synthesis
A chemical synthesis of methyltestosterone from dehydroepiandrosterone (DHEA) with methandriol as an intermediate proceeds as follows:

History
Methyltestosterone was first synthesized in 1935 along with methandriol and mestanolone. It was the second synthetic AAS to be developed, following mesterolone (1α-methyl-DHT) in 1934, and was the first 17α-alkylated AAS to be synthesized. The drug was introduced for medical use in 1936. Society and culture
Generic names
Methyltestosterone is the INN, USAN, USP, BAN, and JAN of the drug and its generic name in English and Japanese, while méthyltestostérone is its DCF and French name and metiltestosterone is its DCIT and Italian name.