purpose of and pros/cons of 3 piece IOLs

Does anyone know the purpose of 3 piece IOLs?

I'm a high myope and an MD I'm considering for cataract surgery said Alcon doesn't make a 1 piece IOL in my prescription. (he says I need a +4.5 power to correct me to  a -.5)

Why does a power lower than..say..+6 require a 3 piece IOL?  

Are 3 piece IOLs larger than 1 piece IOLs?

What are the pros and cons of 3 piece IOLs?

Thanks in advance for any help.

[John C Hagan III, MD, FACS, FAAO]

One piece IOLs have the optic and the two struts that hold it in place (haptics) carved from a single piece of plastic, silicon or other material.  In a 3 piece there are two haptics and one optic that are fastened together.  The thickness, weight, diameter and power are every similiar.

I am not a bio-engineer so I cannnot tell you why different manufacturering techniques are used.

JCH MD

[Capes55]

Thank you again for your help

[JodieJ]

A power lower than +6 does NOT require a 3-piece IOL.  The fact is that the only IOLs made by Alcon in powers lower than +6 happen to be in an older 3-piece model.  I've read that one-piece IOLs have become more popular in recent years because they are easier for surgeons to implant.

Capes55, there is an aspheric monofocal IOL available in the power you need.  It is the SofPort by Bausch & Lomb, available in powers 0 through +34.  It offers the same  enhanced contrast sensitivity/dim light vision benefit as the AcrySof IQ and Tecnis IOLs.  Elsewhere on this forum, Dr. Kutryb has indicated that it is the implant he prefers.  Since your Doc #2 indicated that he would implant a Tecnis if it came in your power, perhaps he would consider using a SofPort.

[John C Hagan III, MD, FACS, FAAO]

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