Monday, February 6, 2012

Cataract Surgery & Lens Implant Pseudoaccommodation

Question: My cataract lens implant works BETTER than it should!! I had a Tecnis® 1-piece IOL implanted a few months ago. My surgeon assures me that this was indeed the lens that was implanted and that it is securely seated in the posterior capsular wall. Nevertheless, despite the fact that the Tecnis® 1-piece is a standard monofocal lens, without glasses I can read a newspaper or alternatively clearly see objects far away. In other words I can accommodate using an IOL that was not designed to accommodate! How can this be?

When I posed this question to my cataract surgeon and to Abbott Medical Optics all I received was congratulations on my good fortune but no convincing explanation. I would have thought that my bizarre situation would be of great interest to the ophthalmology community. What is the explanation for this medical miracle?

Answer: Pseudoaccommodation with Lens Implants after Cataract Surgery is a well known clinical and optical phenomenon that has been researched and reported on for quite some time. Your situation is neither bizarre or completely unpredictable. Certain optical factors such as the presence of "against the rule" astigmatism and higher order aberrations such as coma and trefoil are highly predictive of a set of optical circumstances that create an increased depth of focus allowing patients to see clearly BOTH at far and near after Cataract Surgery. This can further be increased through the use of particular types of aspheric lens implants (IOL) that act to synergistically increase the depth of field thus actually increasing the seeming ability to accommodate. In fact, through careful preoperative measurement of higher order aberrations and through planned construction and location of the Cataract incision along with careful calculation and selection of the IOL and its asphericity, it is possible to ACTUALLY CREATE PSEUDOACCOMMODATION for many patients-AND IN FACT there are Cataract & Refractive Surgeons who do this as a matter of course for their patients who are interested in doing so.

It is estimated that as many as 45% of patients who have had certain types of monofocal lens implants are positively affected by the presence of Pseudoaccommodation and even more might benefit through popper measurement, screening and wound construction. Without seeming cynical, it would be quite understandable why Lens Implant manufacturers might not want either Cataract Surgeons or patients to know too much about this as it would then have the potential to be a suitable substitute for the purchase of the significantly more expensive Multifocal Lens Implants that they clearly see as a greater source of profitability. That said, creating and leveraging Pseudoaccommodation requires extensive measurement, calculation, surgical planning and skill of Cataract Surgeons and thus patients exploring this option should be prepared to pay fees associated with the necessary testing that are not typically covered by Medicare or commercial insurances.

Important Note: The information presented on the About Cataract Surgery Blog or provided in response to a request for information in the Ask Cataract Surgeons section on is not intended to diagnose or treat eye problems, eye conditions or eye diseases including appropriateness of treatment, risks, complications or side effects as related to Cataracts, Cataract Surgery of Lens Implants. In particular a response to an inquiry made on the Ask Cataract Surgeons section of is not meant to take the place of the professional medical care provided by your eye doctor, ophthalmologist and Cataract Surgeon surgeon. Contacting us via e-mail or any other means is not a substitute for medical care.

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