Corneal Aberrations in Keratoconus: A Pentacam Scheimpflug Imaging Study

Öz

Objective To investigate high-order corneal aberration alterations at different KC stages using a Pentacam Scheimpflug camera (OCULUS, Wetzlar, Germany), and to compare data with healthy eyes Materials and Methods This retrospective comparative study investigated clinical data of 50 patients (100 eyes) with KC and 59 healthy individuals (118 eyes) who underwent corneal topography using the Pentacam Scheimpflug camera in our clinic. Demographic characteristics, total aberrations, HOAs, coma and spherical aberrations of all participants were extracted and recorded. Results Mean age in the KC group was 29.7±10.3 years and 32.1±12.4 years in the control group. These two groups were compatible in terms of age and sex (P=0.11; P=0.76, respectively,). In the keratometric classification, KC was mild in 63, moderate in 23, and severe in 14 eyes. Differences in low-order astigmatism, trefoil, coma, tetra-foil, high-order astigmatism, high-order spherical aberration, and root mean square values between eyes with KC and healthy eyes were statistically significant (P<0.05). In addition, there were statistically significant differences in the corneal aberrations between the keratometric classification groups. Conclusions There is direct proportionality between the KC stage and corneal HOA changes, which may be helpful for staging and improving the safety of refractive surgery.

Anahtar Kelimeler

• Corneal Aberrations
• Corneal Topography;
• Irregular Corneal Astigmatism
• Keratoconus
• Pentacam Scheimpflug Camera

Keratokonustaki Korneal Sapmalar: Bir Pentacam Scheimpflug Görüntüleme Çalışması

Öz

Amaç Farklı keratokonus evrelerindeki yüksek dereceli kornea aberasyon değişikliklerini Pentacam Scheimpflug kamera ile araştırmak ve verileri sağlıklı gözlerle karşılaştırmak Gereç ve Yöntem Bu retrospektif karşılaştırmalı çalışmada, kliniğimizde Pentacam Scheimpflug kamera kullanılarak kornea topografisi yapılan keratokonuslu 50 hasta (100 göz) ve 59 sağlıklı bireyin (118 göz) klinik verileri araştırıldı. Çalışmaya dahil edilen tüm katılımcıların demografik özellikleri, toplam aberasyonları, yüksek dereceli korneal aberasyonları, koma ve küresel aberasyonları kaydedilip analize edildi. Sonuçlar Keratokonus grubunda ortalama yaş 29.7 ± 10.3 yıl ve kontrol grubunda 32.1 ± 12.4 yıl idi. İki grupta yaş ve cinsiyet açısından uyumlu idi (sırasıyla P = 0.11; P = 0.76). Keratometrik sınıflandırmaya göre 63 gözde hafif, 23 gözde orta ve 14 gözde şiddetli keratoconus var idi. Düşük dereceli astigmat, yonca (trefoil), koma, tetra-folyo, yüksek dereceli astigmat, yüksek dereceli sferik aberasyon ve kök ortalama kare (root mean square) değerleri keratokonuslu gözler ile sağlıklı gözler arasındaki farklılıklar istatistiksel olarak anlamlı idi (P <0.05). Ayrıca keratometrik sınıflandırma grupları arasında kornea aberasyonlarında istatistiksel olarak anlamlı farklılıklar var idi. Sonuç Keratokonus evresi yüksek dereceli korneal aberasyon değişiklikleri ile ilişkilendirlmektedir. Bu ilişki özellikle refraktif cerrahinin evrelendirilmesi ve güvenliğinin iyileştirilmesinde yardımcı olabilir.

Anahtar Kelimeler

• Korneal Sapmalar;
• Korneal Topografya;
• Düzensiz Korneal Astigmatizma
• Keratokonus;
• Pentacam Scheimpflug Kamera

Kaynakça

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