KERATOKONUSTA KORNEA ENDOTEL HÜCRE ÖZELLİKLERİNİN TOPOGRAFİK EKTAZİ GÖSTERGELERİ İLE KARŞILAŞTIRILMASI

Abstract

Amaç: Keratokonuslu gözlerde kornea endotel hücre özellklerini incelemek ve topografik keratokonus tarama indeksleri ile korelasyonunu araştırmak.

Gereç ve Yöntemler: Bu prospektif çalışmada keratokonus hastalarında ve sağlıklı gözlerde kombine Scheimpflug-Placido disk kornea topografi cihazı (CSO Sirius, Floransa, İtalya) ile ön yüzey apikal kurvatür, en ince kornea kalınlığı (EİKK), simetri indeksi, keratokonus verteksi ve Baiocchi-Calossi-Versaci (BCV) indeksi adı verilen keratokonus tarama indeksleri kaydedildi. Kornea endoteli temassız speküler mikroskopi cihazı (Konan Cell Check SL, Hyogo, Japonya) ile incelendi. Endotel hücre yoğunluğu (EHY), hücre alanlarının değişkenlik katsayısı (DK) ve altıgen hücre yüzdesi (AHY) kaydedildi. Keratokonus tarama indeksleri ve endotel hücre özellikleri keratokonuslu gözler ve sağlıklı gözler arasında karşılaştırıldı. Topografik indeksler ile endotel hücre özellikleri arasındaki korelasyon incelendi.

Bulgular: Çalışmamızda keratokonus grubunda 45 keratokonus hastasının 70 gözü ile kontrol grubunda 50 sağlıklı gönüllünün 50 gözü bulunmaktaydı. Hastalık şiddetine göre 24 göz hafif, 36 göz orta, 10 göz ileri keratokonus grubuna alındı. Keratokonus grubunda DK kontrol grubuna göre anlamlı olarak yüksekti (p=0.015). Ortalama EHY ve AHY ise kontrol grubundan düşüktü, ancak bu fark istatistiksel olarak anlamlı değildi. Keratokonus evreleri arasında endotel hücre özellikleri açısından anlamlı fark saptanmadı (p>0.05). EİKK ile EHY arasında zayıf ama anlamlı korelasyon saptandı (r=0.231; p=0.011). DK ile keratokonus tarama indekslerinin büyük kısmı ve apikal kurvatür arasında zayıf ama anlamlı korelasyon olduğu izlendi (r=~0,2; p<0.05).

Sonuç: Keratokonusta endotel hücre alan varyasyonu artmaktadır. Bu artış topografik keratokonus tarama indeksleri ve apikal kurvatür ile koreledir. Kornea endotel hücre özelliklerinin keratokonus şiddeti ile beraber değişebildiği göz önünde bulundurulmalıdır.

Keywords

• Keratokonus,kornea topografisi,kornea endotel hücre yoğunluğu,speküler mikroskopi

The Comparison of Corneal Endothelial Cell Properties with the Topographic Ectasia Indexes in Keratoconus

Abstract

Objective: To investigate the corneal endothelial cell characteristics in eyes with keratoconus and to analyze their correlation with topographic keratoconus screening indices.

Material and Methods: In this prospective study, apical curvature and keratoconus screening indexes including thinnest corneal thickness (TCT), symmetry index, keratoconus vertex, and Baiocchi-Calossi-Versaci index were recorded in keratoconus patients and healthy eyes using a combined Scheimpflug-Placido disc corneal topography device (CSO Sirius, Florence, Italy). Corneal endothelium was examined with non-contact specular microscopy device (Konan Cell Check SL, Hyogo, Japan). The endothelial cell density (ECD), coefficient of variation of cell areas (CV) and percentage of hexagonal cells (HEX) were recorded. The keratoconus screening indexes and endothelial cell properties were compared between the keratoconic and healthy eyes. The correlation between topographic indexes and endothelial cell properties was evaluated.

Results: In our study, there were 70 eyes of 45 keratoconus patients in the keratoconus group and 50 eyes of 50 healthy volunteers in the control group. Twenty-four eyes were recruited to mild, 36 eyes to medium, and 10 eyes to advanced to keratoconus groups according to the severity of disease. In keratoconus group CV was significantly higher than in the control group (p=0.015). Mean ECD and HEX were also lower than the control group, but this difference was not statistically significant. No significant difference was found between the stages of keratoconus in terms of endothelial cell characteristics (p>0.05). A weak but significant correlation was found between TCT and ECD (r=0.231; p=0.011). There was a weak but significant correlation between CV and most of the keratoconus screening indexes and apical curvature (r=~0.2; p<0.05).

Conclusion: Endothelial cell area variation increases in keratoconus. This increase is correlated with topographic keratoconus screening indexes and apical curvature. It should be kept in mind that corneal endothelial cell characteristics may change with the severity of keratoconus.

Keywords

• Corneal topography,corneal endothelial cell density,keratoconus,specular microscopy

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