Toric IOL With Frosted Haptics Shows Similar Stability to Non-Toric Version

At least 2 manufacturers have developed toric intraocular lenses (IOLs) with textured haptic arms that may create more static friction with the capsular bag, and thus reduce postoperative rotation, according to a study published in Clinical Ophthalmology. Clinical trial investigators compared an IOL prototype that has squared, frosted haptics with a non-toric IOL in a proof-of-concept study.

The open-label clinical trial (ClinicalTrials.gov Identifier: NCT04327518) included 202 eyes of 125 individuals (average age 68.4+8.3 years), who were followed for 3 months. Objective assessments involved photographs graded by 2 independent, masked examiners.

One day after implant, mean absolute rotation of toric lenses was 0.82±1.0°, and at 1 week 0.84±0.92°, a similar result to the comparison non-toric monofocal —  0.73±0.75° at 1 day, and 0.71±0.69° at 1 week. Both trials show no meaningful change in rotation between 1-day and 1-week following surgery. 

With the toric IOL, 98.9% of patients had 5° rotation from the target axis or less after 1 day, and 99.5% at 1 week, compared with the non-toric which reached 100% at both time points. With both lenses, mean signed lens rotation showed a slight clockwise drift; with the toric lens, this change measured 0.23±1.27° at 1 day and -0.07±1.25° after 1 week. Also, no significant correlations appeared between axial length and rotation.

Average monocular uncorrected distance visual acuity (UDVA) with the toric IOL was 0.09±0.22 logMAR 1 day after surgery, and 0.03±0.14 logMAR at 1 week. Best-corrected distance visual acuity (BDVA) after 1 week was -0.06±0.10 logMAR. Further, 84.0% of eyes exhibited a cylinder equal to or better than 0.5 D of target, and 98.5% within 1.0 D. In a 1-week survey, surgeons were “satisfied” or “very satisfied” with rotational stability in 98.0% of cases, and UDVA in 97.5%. The analysis noted no events of lens repositioning or exchange due to misalignment.

“Low residual refractive astigmatism (0.30±0.35 D at 1-week), excellent [uncorrected distance visual acuity] (monocular 0.03 ± 0.14 [~20/21] and binocular -0.06±0.10 [~20/17] logMAR), and very high rates of surgeon satisfaction were achieved with the [toric IOL], demonstrating the benefits of this toric lens design,” according to the investigators.

Limitations of this paper included assessment for just 1 textured-haptic toric IOL, and inclusion only of individuals predicted to reach BDVA of at least 20/30. On the other hand, investigators speculate prototyping new haptics in non-toric IOLs may predict the design’s stability when applied to toric lenses.

Disclosures: Johnson & Johnson Surgical Vision, Inc. funded this study. Several study authors have disclosed affiliations with Johnson & Johnson, or the biotech and eye care product industries. Please see the original reference for a full list of disclosures.