Clarification of General Cataract Questions

Dr. O:
Would appreciate your thoughts on the following questions:
l. RE: One Piece Molded IOLs (i.e. the Alcon Toric IOL) -
Are there any drawbacks to this IOL with wider haptics compared to the 3-piece
haptic IOLs? Do they pose any implant problems, and how well do they adhere to
the capsular bag?
2. RE: Regaining Depth Perception -
What is the best type of IOL to implant and how should they be configured in order to regain one's depth perception - (such as is so essential in architectural work, etc.)
Would you suggest mono IOLs in both eyes with the diopters set within close range of each other in order to get the L/R eye to see depth?
What actually does the eye do in order to see depth?
3. How long (generally) does it take for a cataract to mature to the point where in order to extract the lens, a larger incision must be made?

Thank you again for your indepth responses.
Sincerely,
Laura 5121

[Ray T Oyakawa, MD]

1)  This IOL probably needs to have less complications  for implantation. A surgeon experienced with the IOL should not have a problem. This IOL is more difficult in implant if the capsular bag is compromised such as a radial tear in the anterior capsule or posterior capsular rupture.  The haptic can stick to the optic making unfolding difficult at times.  One must also make sure the haptics are completely in the bag.    This is frequently an unrecognized complication that can cause problems later with pigment dispersion, glaucoma, etc. due to the iris rubbing the haptic.  Due to the previous reason, this IOL can not be implanted in the sulcus.  These lens are very good and adhere well to the capsular back.  This makes the Toric lens stay in place when implanted.  However, very infrequently, the toric IOL can rotate after implantation requiring repositioning.  This may be more common in high myopes with a large capsular bag. At the same time they can be removed much easier than other IOLs.  

I always have a three piece IOL as a backup.  This lens can be implanted if there is capsular rupture.

2)  The best depth perception is when both eyes are equal in refraction. A slight monovision will decrease depth perception.  I would recommend  Alcon Toric IOLs if the eyes have astigmatism and aim for plano.  Depth perception occurs from each eye looking at an object from a slightly different angle.

3)  Hard question to answer.  I have seen eyes with cataract progression in a few months when I though it would take a few years and the opposite.  Cataract removal depends heavily on the patient's need.  You might remove 20/25 cataracts in a surgeon and not remove a 20/80 cataract in a patient who does not read, drive or watch TV.  I have taken out cataract in patients with 20/20 vision but when stressed with light (glare test) the vision drops to 20/40.  These patient usually complain of glare, difficulty driving at night or toward the sun.  Our examining room check vision in the most ideal high contrast environment and does not necessarily represent real life.

[peakhope]

Before getting a toric IOL, do consider your other options: Laser surgery or LRI's. There is no single best option for everyone, as each has pros and cons. And some eye might have conditions that rule out one or more of the choices.

I had LRI's and am extremely happy with them.