Dptr extremes 22-31 dptr

Since nearly all cataracts after previous myopia surgery were nuclear cataract it is not surprising to see that the mean refractive anomaly before surgery was -3.86 in the myopia group.

After cataract surgery and after eventual Lasik and piggy back surgery the mean and extreme values for Sf.Eq.

were in the myopia group 0.47 +/1.3 D(extremes +2 to -3) in the myopia group and in the hyperopia group.

0.08+/-0.28(extremes -0.5 to +1.25). This learns us that the calculation was much easier after hyperopic compared to myopic refractive surgery²¹ since the outcome was better in hyperopia. But however the pre-existing refractive anomaly was much higher in myopia than in hyperopia.

Follow-up and Secondary Procedures after Cataract Surgery

We started Excimer laser surgery in 1991 and at that time very high myopia values were treated.²²

The mean follow up after cataract surgery in the myopia group was 1850+/-931 days with the longest follow up being 2981 days: 27 eyes had a follow up of at least 3 years and 516+/-612 days I for the hyperopes.In the hyperopia group were more recently operated eyes included.

During the follow up in this whole group: 11 eyes needed a YAG laser capsulotomy and 8 needed supplementary touch up with LASIK in order to correct residual refractive errors-spherical or astigmatic.

No complication at all was encountered in this follow up period.

A Piggyback IOL

Since we know that there is a learning curve in calculating the refractive errors after previous surgery it is not a shame to admit that we needed to add an extra IOL in the sulcus in 6 eyes of the myopia group and in one eye of the hyperopia group; the powers of these IOL’s were between -4 and +9 D.All piggy back IOL’s except one were plus lenses. The mean value of the plus lenses was 5.7+/-1.6D.

The secondary surgery itself was always without any problem; the extra IOL was placed in the sulcus. When analyzing these data please remember that some of the earlier implantations were done already in 1999.

SUMMARY

1. Cataract surgery and IOL implantation after previous refractive surgery is extremely rewarding.

2. Technically ,there are no hazards on condition to take the routine precautions for this particular type of surgery.

3. Cataract surgery after previous myopic refractive laser surgery was performed at a younger age compared to the hyperopia population.

4. Exact IOL power calculation may still pose a problem nowadays.

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