In a prospective evaluation including 20 eyes, a trifocal toric IOL effectively reduced astigmatism, had good postoperative rotational stability, provided a full range of excellent uncorrected visual acuity with good contrast sensitivity, caused no significant phoic phenomena, and was associated with high patient satisfaction.
All patients underwent a complete ophthalmological examination preoperatively and three months after surgery. Astigmatism was measured with corneal topography (Sirius, CSO Italia) and optical biometry (IOLMaster 700, Carl Zeiss Meditec).
All of the surgeries were done using a femtosecond laser (LenSx, Alcon) for the corneal incisions, anterior capsulotomy, and lens pretreatment followed by phacoemulsification through a 2.2 mm incision (Centurion Vision Systems, Alcon).
The patients ranged in age from 46 to 75 years; their mean age was 62 years, and all procedures were for cataract.
Preoperatively, mean corneal astigmatism was 1.8 D (range 0.82 to 4.30 D). Mean predicted residual astigmatism was 0.12 D (range 0.01 to 0.71).
The eyes had average axial length (mean 23.9 mm, range 22.16 to 26.99) and anterior chamber depth (mean 3.1 mm, range 2.51 to 3.80).
At three months after surgery, all patients achieved uncorrected visual acuity (VA) of 0.1 logMAR or better at distance, intermediate, and near, and 90% of patients reported complete spectacle independence.
Mean logMAR uncorrected VA was 0.005 at distance, 0.06 at intermediate, and 0.05 at near.
Defocus testing was also done over the range of +1.0 to – 3.0 D. The curve showed peaks at 0.00 D and -1.50 D.
Mean refractive astigmatism was 0.39±0.38 (0-(-)1 D) and mean manifest astigmatism was 0.05±0.22 (0-(-)1 D)
“Refractive astigmatism (This is manifest) was <1 D in all eyes and it was ≤0.50 D in 94% of eyes,” Dr. Akova reported.
Contrast sensitivity testing was also done, and the results showed that all patients maintained normal contrast at all spatial frequencies under both mesopic and photopic conditions.
No patients experienced any disturbing optic phenomena. Three patients (15%) reported mild halos, and only one patient (5%) reported glare, which was also mild.
Visual function was also assessed at three months after surgery using the Visual Function Index Test (VF-14). The best possible score on this instrument is 100, and the patients in the study had a mean VF-14 score of 97.63.
Rotational stability was assessed by evaluating IOL alignment at three months after surgery. Mean rotation was 3.3°, and in no case did the IOL rotate >10°.
“We also saw no evidence of posterior capsule opacification, although the follow-up at three months is still a short duration,” Dr. Akova concluded.
Yonca A. Akova, MD
E: [email protected]
This article was adapted from Dr. Akova's presentation at the American Academy of Ophthalmology 2019 annual meeting. Dr. Akova is a consultant to Alcon.