Should I have posterior ptosis repair or anterior approach with levator advancement? (photos)

The Mullerectomy (posterior ptosis surgery) will burn a bridge.  Every surgery uses up something.  The is no substitute for an in person consultation with a detailed examination.  However, it is highly likely that you have levator dehiscence ptosis.  The problems caused by this will not be addressed with the Mullerectomy and it is highly probably that this surgery will fail.  The reason is that when the levator aponeurosis tendon, which is how the levator palpebral superiors muscle inserts into the eyelid, is disinherited, it is not in place needed to make the Mullerectomy effective.  The result is that in this situation posterior ptosis surgery fails.  Also this approach does not address your other issues.  It does not support your upper eyelid lashes which are ptotic and you have loose eyelid platform skin.  Ideally, then you have this work done, instead of having a hollow upper eyelid, you will have a crease and an upper eyelid fold. You have a fold now but they are asymmetric and very high because your eyebrows are elevated to compensate for the heavy upper eyelid.  What you need in my opinion is anterior surgery to fix the levator dehiscence which will correct the ptosis, you also need an anchor blepharoplasty to define a hard crease in the upper eyelid, snug the eyelid platform skin, and support the upper eyelid lashes.  Surgeons like the posterior approach because the procedure is far less complicated than anterior levator ptosis surgery.  Many eyelid surgeons do not fully understand the anatomy.

Posterior approach ptosis has several advantages:  1) more predictable result; 2) better eyelid contour; 3) scar-less.  It is usually the best technique for mild ptosis repair. That's all I can say without examining you.

Great question!  I can understand the difference in opinions.  The "posterior approach" is appropriate and will improve some aspects of the differences between the eyes.  The "anterior approach" will leave an external scar but allow for greater symmetry and a more accurate result.  You can have the "posterior approach" and if you want a greater change afterwards have an "anterior approach" .  Both approaches will improve symmetry, but perfection is hard to achieve.