Clinical Results Of Opposite Clear Corneal Incisions (Occi) With The Implantation Of A New Non-Diffractive Extended Depth Of Focus (Edof) Intraocular Lens (Isopure®).

To evaluate the efficacy of OCCI during cataract surgery in a large cohort of bilateral cataract patients with pre-existing mild-to-moderate corneal astigmatism, in terms of reduction of corneal astigmatism, unaided visual acuity, spectacle independence and patient-reported photic phenomena.

Vista Alpina Eye Clinic, Visp, Switzerland

Single-center retrospective study including 124 eyes of 62 patients with 0 to 1.5 D corneal astigmatism, undergoing bilateral cataract surgery with implantation of Isopure® (BVI).

Mini-monovision was used in all patients. Algorithm-based OCCI were applied in 68 eyes with pre-existing corneal astigmatism from 0.6 D to 1.5 D. In eyes with 0.4-0.5 D a 2.1 mm near-clear corneal incision was placed on the steep axis, and in eyes with 0.3 D or less the incision was placed at 115°.

Visual acuity, spectacle independence and picture-referenced photic phenomena were assessed 4 to 6 weeks postoperatively.

Three patient subgroups were defined:
A: both eyes non-OCCI (n=16 patients)
B: one non-OCCI eye and one OCCI eye (n=24)
C: both eyes OCCI (n=22)

Postoperative residual refractive astigmatism was 0.60 D in both non-OCCI and OCCI eyes (77% of OCCI eyes < 1.0 D, 61% < 0.75D).

In plano eyes, the postoperative monocular uncorrected distance visual acuity was 0.06 logMAR in both non-OCCI and OCCI eyes.

Binocular uncorrected distance (bUDVA) and intermediate (bUIVA) visual acuities were similar (p = 0.4) in the three patient subgroups:
bUDVA: subgroup A -0.03 ± 0.06 logMAR, B -0.01 ± 0.06 logMAR, and C -0.02 ± 0.09 logMAR; p = 0.4;
bUIVA: subgroup A 0.1 ± 0.11 logMAR, B 0.13 ± 0.10 logMAR, and C 0.15 ± 0.13 logMAR; p = 0.12.

Spectacle independence (far vision 96%, intermediate 95%, near 34%) and rates of photic phenomena (37%) were also similar in the three patient subgroups (both p = 0.4).

A toric version of Isopure® is not yet available and we have instead applied OCCI in bilateral cataract patients with pre-existing corneal astigmatism of up to 1.5 diopters.

Residual astigmatism and clinical outcomes in patients with mild-to-moderate corneal astigmatism treated with OCCI were similar to those in patients with no or only minimal astigmatism. Tolerance to the mild residual astigmatism was excellent.

OCCI are a safe and effective tool to broaden the range of application of Isopure® and allow implantation in patients with mild-to-moderate corneal astigmatism.