Can vertical orbital asymmetry be easily fixed? (Photo)

If your CT scan was not of the 3D variety, this will be needed to assess the bony shape and the position of the orbital floors of both eyes. Assuming there is a vertical bony asymmetry between the two orbits a custom orbital floor-rim implant can designed to elevate the lower eye. While I would not call this surgery easy, the computer designing of the needed implant augmentation makes the surgery more predictable. 

Hello,
Judging from your photo, if you look closely the light reflection on each pupil it is at the same level on both sides (or very close to it).  I therefore think the primary problem is the enophthalmos (eyeball sitting back inside the orbit on that side) rather than the hypoglobus.  
Without looking at your CT it's hard to say why this is happening but typically with the syndrome there is some collapse of the orbital floor.  If so, this can potentially be reconstructed with an implant (preferably custom in such a case) to correct the deformity.  If as you say however the bony orbit looks 'normal' then it could be due to soft tissue atrophy (wasting) within the orbit, which would be difficult if not impossible to correct.
If you have not already I would recommend consulting with a surgeon who has extensive cranio-maxillo-facial experience to discuss this problem further.
Thanks