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

Abstract

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.

Keywords

• iris barycenter
• kappa angle
• photic phenomena
• pupil barycenter
• trifocal intraocular lens

Trifokal Göziçi Lens İmplantasyonu Sonrasında Kappa Açısı ve Fotik Fenomenler Arasındaki İlişki

Abstract

Amaç: Bu çalışmanın amacı, trifokal lens implantasyonları sonrası fotik fenomen ile kappa açısı arasındaki ilişkiyi araştırmaktır. Gereç ve Yöntemler: Çalışmaya 17 kadın ve 18 erkek olmak üzere 35 olgunun toplam 50 gözü dahil edildi. Kappa açısı, pupil barycenter parametresi kullanılarak Lenstar LS900 düşük koherens interferometri cihazı ile hesaplandı. Aynı zamanda iris barycenter parametreleri kullanılarak da hesaplandı. Pupil barycenter mesafesi kullanılarak yapılan hesaplamalara göre hastalar ameliyat öncesi pupil barycenter mesafesi 0,4 mm'nin altında olanlar ve 0,4 mm'nin üzerinde olanlar şeklinde iki gruba ayrıldı. Ameliyat sonrası dönemde şikayetleri ve memnuniyetleri değerlendirmek amacıyla hastalara anket uygulandı. Bulgular: Ameliyat öncesi ortalama pupil barycenter mesafesi 0,38±0,12 mm ve ölçümlerin %52,0'si (n=26) 0,40 mm'nin altında iken, ameliyat öncesi ortalama iris barycenter mesafesi 0,40±0,15 mm ve ölçümlerin %46,0'sı (n=23) 0,40 mm'nin altındaydı. Ameliyat öncesi pupil barycenter mesafesi ile ameliyat öncesi iris barycenter mesafesi arasında istatistiksel olarak anlamlı bir korelasyon yoktu (rs=0,086, p=0,553). Ek olarak, iki grup arasında halo ve kamaşma gibi semptomlar açısından da istatistiksel olarak anlamlı bir fark yoktu (p=0,948). Sonuç: Kappa açısı için üst sınır 0,6 mm olarak dikkate alındığında fotik fenomenlerin meydana gelme sıklığında fark edilebilir bir fark yoktur. Kappa açısı hesaplamalarında kullanılan hem iris barycenter parametrelerinin hem de pupil barycenter parametrelerinin sapma mesafesini belirlemek için etkili bir şekilde kullanılabileceğine inanıyoruz.

Keywords

• iris barycenter
• kappa açısı
• fotik fenomen
• pupil barycenter
• trifokal intraoküler lens

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