Here’s the conundrum. Many of us would like to implant more toric IOLs and wish that patients came to us better prepared to choose a toric refractive package. But not all referring optometrists are equipped to make a definitive recommendation. Those who don’t have topography in the office really can’t be certain whether the patient is a candidate for a toric IOL because that decision has to be based on corneal, rather than refractive, astigmatism.
For those who have topography, I generally advise that patients who have with-the-rule (WTR) corneal astigmatism of 1.4 D or more or against-the-rule (ATR) corneal astigmatism of 0.7 D or more will be good candidates for a monofocal toric IOL or for the Tecnis Symfony toric (Johnson & Johnson Vision) if the patient would like to improve near and distance vision.
For lower astigmats or with referring doctors who don’t have a topographer, I’ve found that the best approach is to encourage optometrists to talk about astigmatism management more generally, in the context of the lifestyle benefits of achieving better uncorrected vision. That gets the patient thinking about options and sets up the opportunity for me to discuss the most appropriate solution, whether that be laser arcuate incisions, limbal relaxing incisions, a toric IOL, toric extended depth of focus lens, laser vision correction or some combination of the above.
When educating referral sources about toric IOLs, here are two more things they need to know about postoperative management:
1. Very high astigmats and those with large eyes or very large capsular bags are the most likely to have residual astigmatism or to have an issue with IOL rotation postoperatively. We need to have an extra level of awareness in evaluating outcomes postop in these patients.
2. That said, toric IOL rotation and the need for repositioning are actually quite rare. In most cases, especially when the spherical equivalent is near plano and the refractive astigmatism is 0.5 D or less, the cause of any postoperative dissatisfaction is most likely to be a small amount of residual error or ocular surface problems. Optimizing the ocular surface and encouraging patients to use their postoperative drops, including artificial tears, are essential.
Disclosure: Yeu reports she is a consultant/adviser for Alcon, Allergan, ArcScan, Bausch + Lomb/Valeant, Bio-Tissue, BVI, i-Optics, J&J Vision, Lensar, Kala Pharmaceuticals, Novartis, Ocular Science, Ocular Therapeutix, Ocusoft, Omeros, Science Based Health, Shire, SightLife Surgical, Sun, TearLab, TearScience, Veracity and Zeiss; does research for Alcon, Allergan, Bausch + Lomb, Bio-Tissue, i-Optics, Kala and Topcon; and has an ownership interest in ArcScan, Modernizing Medicine, Ocular Science, SightLife Surgical and Strathspey Crown.