18 weeks post opp.. folds and puckering are not dissolved - How do I fix this? (photo)

It is still relatively early in the healing and maturation process from your surgery. You can expect continued improvement for at least 6 months. It would be advised  that your defer any surgical intervention for at least that period of time. You may eventually find that the result is acceptable to you. Even if it turns out that you are still in need of a revision, any improvement will allow you to have a lesser surgery. This would serve to improve your final outcome. 

There is a nearly always some degree of irregularity of the lower pole in the setting of a vertical mastopexy. This is a function of the operation itself which foregoes a horizontal excision in favor of a more limited scar burden.While much of this will settle with time, some may require revision which often comes in the form of a limited transverse/horizontal excision and scar.As always, discuss your concerns with a board certified plastic surgeon (ABPS).

Dear cmstrangel,I understand your concern and it is quite normal to be concerned about the outcome following a breast lift surgery. However, you are still in the very early stages of the healing process.Your will need to be patient at this moment and follow what your surgeon has instructed you to do post operatively.At the early stage of the healing process, the tissues are still swollen. Once the swelling subsides  you will be able to see the final result of your surgery.Daniel Barrett, MD
Certified, American Board of Plastic Surgery
Member, American Society of Plastic Surgery
Member, American Society of Aesthetic Plastic Surgery

With vertical reduction mammoplasty in certain surgeons hands a small revision is necessary is the puckering does not resolve.  I would wait closer to 6 months to make that decision whether a small revision under the breast is necessary.  The result above the fold along with the shape looks good at this point and the lower area of concern can be corrected.

Managing the excess skin of the lower portion of the breast following a short scar procedure is tricky. It still beats a horizontal scar in my opinion.  Give it up to a year, follow your surgeon's advice, and do not try to force an early revision.