Mystery Case: What are these linear marks?

You’re doing a routine case and it is progressing beautifully. A good incision, a centered 5-mm capsulorhexis, efficient nucleus removal, but when it comes to IOL insertion, we notice something. There are multiple small linear marks that are noted.

Are these lines bits of cortex? Are they scratches on the IOL? It turns out that these lines are micro-fractures in the optic of the hydrophobic acrylic IOL. When we place the IOL into the injector cartridge, we lubricate it with viscoelastic and then as we advance the pusher, the IOL is curled and compressed. This compression can rarely cause linear damage to the IOL.

In this case, the lens was perfectly loaded and we followed the manufacturer’s instructions exactly. Higher power IOLs do have thicker optics which can contribute to the risk of optic fractures. We tend to use larger caliber cartridges with these higher power IOLs. Interestingly, some of the lower power IOLs which are meant for highly myopic eyes, particularly in the low single digits and minus powers (such as +5 to -5), can have very thick optics despite the low dioptric power.

Should we leave this IOL in place or do an IOL exchange? Either option is fine, but my recommendation is to leave it and wait. If the patient is symptomatic in the post-op period, we can easily return to the operating room to perform the IOL exchange. We have all seen many patients with posterior capsule striae and haze who are surprisingly asymptomatic. We have to weigh the risk of the IOL exchange procedure versus the degree of symptoms caused by the optic imperfections.

Click below to watch the video of this IOL with fractures of the optic:

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