REMINDER When ophthalmologist Curtin G. Kelley, MD, treats astigmatism, he puts a sticky note on the operating machine that tells him the lens power and rotation where it should end up.

I've spent my professional life correcting the blurry vision caused by astigmatism, which occurs when the surface or lens of the eye is unevenly curved. Much of that correction happens in the office, with prescribed glasses or contact lenses. But sometimes, the best way to correct astigmatism is through surgery.

One type of astigmatism correction surgery — perhaps the best known — is laser vision correction. This procedure reduces the need for glasses by using a laser to create a flap in the cornea, lifting the flap and reshaping the cornea. In another type of surgery, the flap is created with a manual incision, rather than a laser. Astigmatism correction surgery can also be combined with cataract surgery when the surgeon inserts a corrective toric lenses directly into the eye. There are many conversations to be had — and decisions to be made — before the patient arrives for surgery. Here's what you should know about helping patients get to the post-operative finish line with no more astigmatism.

1 See it
When a patient wants to end her dependence on glasses or contact lenses, one of an ophthalmologist's first steps is to analyze the type of astigmatism the patient has. The 3 primary types of astigmatism are myopic (nearsightedness), hyperopic (farsightedness) or a combination of the two. Because astigmatism can be masked by prior contact lens use, patients should stop wearing their contacts before their baseline astigmatism levels are measured: 1 week for soft daily wear lenses and 3 to 4 weeks for hard, or rigid glass permeable, lenses. This lets the eye unmold for an accurate measurement revealing the patient's true baseline astigmatism. It's also important before surgery to manage any ocular surface diseases. This could mean, for example, treating severely dry eyes before taking measurements and committing to astigmatism correction surgery.

2 Line it up
In order to surgically correct a patient's astigmatism during cataract surgery, we need to make sure the "planets" align. By this I mean that all 3 of a patient's key astigmatism measurements must match for the patient to be a surgical candidate. We take measurements in the office to ensure this alignment.

The eyeball is a 360-degree sphere, and we measure it in degrees. When we take measurements of the eye, we're looking at axial length (the front-to-back measurement of the eye) and the front of the eye curvature. We use corneal topography and manual keratometry to measure the eye's curvature and analyze astigmatism. A third technique, using an optical biometer, takes those same measurements, but also measures axial length.

Because astigmatism correction is all about alignment, it's key for the surgery to hit the eye at just the right axis. You can connect the optical biometer to a toric alignment device in the surgical suite to confirm the alignment of the lens during surgery. Measurements must be similarly aligned for laser vision correction surgery, though instead of replacing the lens, the surgeon is reshaping the cornea. We use a series of custom analyzers in the office to, for example, measure iris markings and find 6 o'clock and 12 o'clock on the patient's eye. The surgeon will reconfirm those measurements under the laser scope in the surgical suite to ensure he's treating the astigmatism in the right place.

???Because astigmatism correction is all about alignment, it's key for the surgery to hit the eye at just the right axis.

3 Discuss it
Once we've assessed the patient's level of astigmatism, and her candidacy for surgery, it's time to help patients understand the importance of treating astigmatism. The surgeon will educate the patient about the negative impact astigmatism can have on her vision. People who don't have astigmatism corrected often face complications, such as ghost vision and double vision. It can also make poor night vision even worse.

Astigmatism affects vision at all focus points: near, medium and far. We make it clear to the patient that we want to do everything we can to reduce the astigmatism, but not overtreat it.

It's important to note that neither laser vision correction surgery nor the surgical implantation of astigmatic lenses during cataract surgery are typically covered by insurance. Both offer a great opportunity to get the patient out of glasses or contacts, but the implants tend to cost more. Nevertheless, inserting corrective lenses during cataract surgery is becoming a wonderful option for eliminating astigmatism.

ADD ON Treating astigmatism is a non-covered service, so facilities can charge patients additional fees for improved vision outcomes.

4 Address it
Once the plan is in place, it's our job as a surgical team to ensure it is properly executed. Every step, from the initial, in-office evaluation to patching the corrected eye at the end of the procedure, is a potential error source. That's why it's essential for the surgical staff to be on the same page as the surgeon. We mark the eye to create a reference point for surgery. We either use surgical cameras to intraoperatively confirm the IOL is where it's supposed to be aligned or make alignment marks at 6 o'clock and 12 o'clock on the patient's numbed eye. When I'm performing surgery, I put a simple sticky note on the operating machine that tells me the lens power and rotation where it should end up. The scrub nurse uses a sterile marker to write the same numbers down elsewhere — with the promise not to let me out of the surgical suite until we confirm the lens is where it should be.

5 Tweak it
As with all surgeries, astigmatism correction requires some post-operative management. Often patients need a minor touch-up procedure, which is often part of the package for premium patients. While most implantable lenses are quite stable, they do sometimes rotate away from their intended location post-surgery. To correct this, the surgeon can do a minor procedure to make a small adjustment of the tilt in the eye. OSM