Improving cataract surgery outcomes in eyes requiring endothelial corneal transplants

Prior to any cataract operation, measurements are obtained to determine the power of the intraocular lens (IOL) to be implanted once the cataract is removed.  These measurements include the curvature of the cornea, the length of the eye (axial length), the position and thickness of the cataractous lens, the thickness of the cornea, the refractive error of the eye, and maps of the anterior and posterior corneal curvature (topography and tomography).  An accurate prediction of the refractive error of the eye after cataract surgery can be determined by using these measurements in several lens formulas.  My goal for cataract surgery is to perform the operation safely and without complication, but also to accurately measure and predict the refractive error of the eye.  This allows me to select the correct power and best IOL for each individual patient.

Descemet stripping automated endothelial keratoplasty (DSAEK) is one of the preferred treatments for endothelial failure and endothelial dystrophies, such as Fuchs corneal dystrophy.  DSAEK is sometimes performed at the same time as cataract surgery, particularly when patients have both endothelial dysfunction and cataract.  Combining the procedures can be more convenient for patients and helps patients avoid a period of time with poor vision between scheduled separate procedures.  DSAEK is sometimes performed after cataract surgery, should the endothelium be considered healthy enough for cataract surgery to be done alone first. 

The curvature of the cornea changes with a DSAEK operation and can therefore impact the power of the IOL selected to be inserted at the time of cataract surgery.  The refractive error of an eye having DSAEK surgery typically changes by approximately +1 to +1.5 diopters.  That means if a lens is selected without taking into account the DSAEK operation, a patient would end up with more than +1 diopter of refractive error, requiring correction with glasses or contact lenses for both distance and near vision.  Some recent studies have looked at the data and determined that changes in both the anterior and posterior cornea curvature play a role in this hyperopic (far-sighted) shift.  Accurate measurement of both anterior and posterior corneal curvature and adjusting the lens choice to take into account the shift caused by DSAEK surgery, allows me to give patients excellent postoperative vision, with minimal refractive error. 

Please discuss all of your questions with me during your consultation, to be sure you fully understand all of these issues and their implications for your vision. 

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s