The Relationship between Kappa Angle and Photic Phenomena after Trifocal Intraocular Lens Implantation

Koç H., kaya f.

Düzce Tıp Fakültesi Dergisi, vol.25, no.2, pp.173-178, 2023 (Scopus) identifier

  • Publication Type: Article / Article
  • Volume: 25 Issue: 2
  • Publication Date: 2023
  • Doi Number: 10.18678/dtfd.1278566
  • Journal Name: Düzce Tıp Fakültesi Dergisi
  • Journal Indexes: Scopus, Academic Search Premier, CINAHL, EMBASE, Directory of Open Access Journals, TR DİZİN (ULAKBİM)
  • Page Numbers: pp.173-178
  • Istanbul Medipol University Affiliated: Yes


Aim: This study aimed to investigate the relationship between photic phenomena and the kappa angle after trifocal lens implantations. Material and Methods: Fifty eyes of 35 cases, 17 female and 18 male, were included in the study. The kappa angle was calculated with the Lenstar LS900 low-coherence interferometry device using the pupil barycenter parameter. It was also calculated by using the iris barycenter parameters. According to the calculations using the pupil barycenter distance, the patients were divided into two groups with the preoperative pupil barycenter distance below 0.4 mm and above 0.4 mm. A questionnaire was applied to the patients to evaluate complaints and satisfaction in the postoperative period. Results: The mean preoperative pupil barycenter distance was 0.38±0.12 mm and 52.0% (n=26) of the measurements were below 0.40 mm, while the mean preoperative iris barycenter distance was 0.40±0.15 mm and 46.0% (n=23) of the measurements were below 0.40 mm. No significant correlation was found between the preoperative pupil barycenter distance and the preoperative iris barycenter distance (rs=0.086, p=0.553). Additionally, there was no statistically significant difference between the two groups concerning symptoms such as halo and glare (p=0.948). Conclusion: When considering a kappa angle upper limit of 0.6 mm, there is no discernible difference in the frequency of occurrence of photic phenomena. We believe that both iris barycenter parameters and pupil barycenter parameters, utilized for kappa angle calculations, can be effectively employed to determine the deviation distance.