Evaluating a toric lens with low add power

April 1, 2014

Dr Morris recently discussed his study, evaluating the Lentis MF-15 toric lens as an effective treatment for astigmatism despite having a low add power. Here, we present the key outcomes of his talk.

His study evaluated the clinical performance of the Lentis MPlus MF-15 (Oculentis, Berlin, Germany), which is a multifocal toric lens with a rotationally asymmetric design, in patients with preoperative corneal astigmatism.1 "One of the things we were particularly interested in looking at, was how effective this lens would be at delivering reading vision," he said.

The study

Both uncorrected and corrected distance and near vision were assessed pre- and postoperatively. Manifest refraction, keratometry, operative and post-op complication rates were measured, and patient satisfaction, spectacle independence and symptomatology were assessed from inspection of electronic case notes.

Results

The team found that 53.8% of their study group achieved N6, which is roughly equivalent to J3, and 80% achieved N8. "So, although the lens has low add power," continued Dr Morris, "it still delivers good reading vision in about 60% of patients."

Regarding accuracy, he noted that 88% of patients were within 0.5 D and 98% were within 1 D spherical equivalence. "As far as correcting astigmatism is concerned, the vector analysis plot showed that 92% of eyes were within ±1 D error vector, demonstrating that this lens effectively treats astigmatism," he said.

Summary

So, despite only having a low add power the Lentis MF-15 toric lens was found to effectively treat astigmatism and enhance both distance and near vision. "We had 60% spectacle independence when reading for our patients and in our questionnaires no patients had significant dysphotopsia with this low powered lens," he concluded.

Reference

1. R. Morris, 'Clinical performance of a multifocal toric intraocular lens with a rotationally asymmetric design and +1.50 addition', Free Paper Presentation, ESCRS 2013, Amsterdam, The Netherlands.