Ventilation-perfusion (V/Q) scan is a specialized test that uses a radioactive substance to show the parts of the lungs that are getting oxygen (ventilation scan) and getting blood flow (perfusion scan) to see if there are portions of the lungs with differences between ventilation and perfusion.
Moleskin may be the first commercial blister treatment and prevention product I remember using. My dad always kept some moleskin in his pack and at the first complaint of any hot or sore feet, out it would come.
At the first sign of outbreak, apply a drop of Tea Tree oil diluted with carrier oil on the blisters several times throughout the day. For pain and discomfort, diluted Lavender essential oil works well. Other helpful essential oils for cold sores all work best when diluted with carrier oil such as sweet almond oil.