What causes visible veins post sclerotherapy?
Thanks for your query.
Your absolutely right in asking the right question : If there were some kind of phlebitis going on should there not be swelling?
Since the phlebitis is a local condition if the vein, it may not give swelling 'locally' unless the inflammation progresses beyond the outer lining of the vein ( tunica adventitia ).
And the area can not be swollen unless the venous drainage is totally blocked, meaning in your case the area of lower leg and ankle are drained well bu another veins.
Trapped blood from the sclerotherapy might have given the swelling immediately.
No venous insufficiency NOR reflux
This does not mean that there is venous insufficiency or reflux.
As there is no edema, this is suggestive of the best collateral venous drainage.
If the valves along the collateral veins are intact, there is no fear of potential of new varicose veins development.
This will take time to settle. The body too takes care of this and heals on its own. There is no redness no there is nothing to worry about infection much. Pressurized vein sensation is due to entrapped edema into the vein, there is no way for the edema to leak out and get reabsorbed immediately.
Do not rub over it. No local ointments really work. Give rest to the are. Keep the leg in elevated position above the heart level , whenever possible / you are taking rest or lying down. May help relive the pain.