Conclusion: if the scalp is injected with plasma, that does not invalidate the fast. That is in contrast to injection of blood via a vein, which takes the place of food and drink, so the fast is invalidated thereby.

If it is possible to delay the elective surgery until after Ramadan without causing any hardship or difficulty, then it is not permissible for you to break the fast because of that.

It is permissible to use a laser for removing the hair that the Lawgiver has commanded us to remove and for other permissible uses unless trustworthy doctors state that the body may be harmed by that. Laser hair removal does not break your fast because it has nothing to do with fasting.

The correct view is that swallowing mucus does not break the fast because it does not come under the same heading as food and drink. Putting a finger in one’s ear does not break the fast either.

The fast of one who has intercourse with his wife at night and wakes up in the morning in a state of janabah (major ritual impurity) is still valid. For more, please see the detailed answer.