Implantation of a Bitoric Trifocal Lens: 1-Year Results
Purpose
To evaluate the visual outcomes and quality of vision after implantation of a bitoric trifocal IOL implantation and comparison with its bifocal version.
Methods
This retrospective quality management investigation comprises results after bilateral implantation of bitoric trifocal aspheric intraocular lens (IOL) (LISA TD 939, Carl Zeiss Meditec) in 40 patients and of the toric bifocal IOL (LISA TD 909, Carl Zeiss Meditec) in 40 patients. Follow-up exams have been performed monocular seven days postoperatively, binocular exams followed after 1 and 3 month after surgery. Subjective refraction (SR), defocus curve (DC), contrast sensitivity (CS), halos and glare assessment (HGA) and a patient questionnaire were documented.
Results
The 3 month postoperative SEQ was -0.05 ± 0.04 logMAR, UDVA was 0.0 logMAR. Uncorrected Intermediate (UIVA) and near (UNVA) visual acuity were comparable between both IOL types (UIVA < 0.1 logMAR, UNVA < 0.2 logMAR). The respective defocuscurve showed 2 peaks for near- and far distance VA. UIVA was represented by a plateau instead of a peak at around 70 cm with a decimal visus of 0.05 ± 0.01 logMAR. The target refraction (+/- 0.5D SEQ) was achieved in all patients. No postoperative IOL rotation or change of refraction occurred. CS of the toric trifocal IOL was comparable to CS of phakic younger patients. Photopsia like halos and glares occurred in almost all cases, but with an average size and intensity of less than 30% of the maximum possible.
Conclusion
Considering life style aspects of most of our patients in case of a computer-based daily routine, as well as menage, handcraft or night driving, the trifocal lens accomplishes patients needs better compared to the former bifocal generation IOL including tricky light conditions, especially in younger patients. All patients are able to conduct nocturnal car trips.