What is screening?
Screening means looking for something that you don't now that you have, so it can be identified and if needed treated before it causes any issues.
With hht screening means looking for any abnormal blood vessels that may cause you any prolems.
Screeing and treatments may cause harm, so doctors carefully work out which types or what place is best to screen for each individual.
In case of pumonary avm's the benefits from screening and treating them far outweighs the risks and since pumonary avm's are common in people with hht, it is recomend that screening of the lungs is done in a person with hht.