Resident's Review

My Experience With a T9 Toric Lens

By Matthew C. Ralstin, MD

A 79-year-old patient presented with complaints of difficulty focusing during daily activities. She'd been wearing spectacles as long as she could remember. Her best-corrected vision was 20/50 in each eye with a refraction of −7.25 +6.00 ×180 OD and −7.00 +6.25 ×174 OS.

Preop, Surgery and Postop

The patient had moderate to severe (3+) nuclear sclerotic cataracts in both eyes. Pre-operative keratometry readings agreed with measurements from the IOLMaster (Carl Zeiss Meditec). She had 4 to 5 diopters of against-the-rule astigmatism.

Because the patient had a great deal of corneal astigmatism, I asked if she would like to be less dependent on eyeglasses. She couldn't remember not needing her glasses but was very interested in my IOL recommendation of the SN6AT9 Alcon lens.

After entering her keratometric readings into the AcyrSof IQ Toric IOL Calculator and reviewing her readings, I recommended the T9 toric lens for this patient because it was aspheric and also offered the best potential for achieving decreased spectacle independence for distance postoperatively due to the amount of astigmatism the IOL could correct at the corneal plane. I performed surgery on her right eye using the Alcon Infiniti system. I made a 2.4 mm temporal clear corneal incision. There was 0.5 D of surgically induced astigmatism.

She required more phaco energy due to the denseness of her cataract and her cornea became hazy during surgery. We rotated the lens and were close to where we wanted the lens to be positioned. We then removed the viscoelastic gel and realized we were a bit under-rotated. We had some difficulty visualizing because of her hazy cornea, so we decided to leave the lens where it was. There were no further surgical complications.

At the first postop visit, the patient reported that she can see her alarm clock when she wakes in the morning, which she's never been able to do even when she was much younger and without cataracts. She notices her vision is greatly improved. She has 20/40 uncorrected vision and she's happy. She recently had cataract surgery on her left eye, resulting in 20/40 uncorrected visual acuity on postop day 1. She reports that she doesn't reach for her glasses like she used to — the ability to not only remove the cataract but also to correct her preexisting corneal astigmatism in a single procedure has made a difference in her vision.

In Closing

I enjoyed the opportunity to help this patient become less dependent on her spectacles. I've had several patients with lower-powered toric lenses who are very happy and enjoy excellent uncorrected vision. I learned that with a higher powered toric, it's very important to be meticulous when positioning the lens in the intended axis, however these patients have always known bad quality of vision since they were younger. Debulking the majority of the corneal astigmatism is still a benefit to these patients. I'm excited about the higher power IQ Toric IOLs, and plan to take advantage of this lens that allows for the correction of large amounts of astigmatism and the cataract with a single procedure. nMD

Dr. Ralstin recently completed his ophthalmology residency at Indiana University. He will be practicing comprehensive ophthalmology with the Whipple Eye Center in Avon, Indiana. Dr. Ralston has no relevant financial disclosures.