Pterjiumda Topografik Keratokonus İndekslerinin İncelenmesi

Abstract

Amaç: Pterjiumlu gözlerde topografik keratokonus indekslerindeki değişiklikleri değerlendirmek ve pterjiumun kornea morfolojisi üzerindeki etkisini ortaya koymaktır. Materyal ve metod: Pterjium tanısı konulan 78 hastanın tek gözü çalışmaya dahil edildi. En iyi düzeltilmiş görme keskinliği ve biyomikroskopik muayene yapıldı. Hastalar pterjium evresine göre üç farklı gruba ayrıldılar. Scheimpflug tabanlı kornea topografisi kullanılarak, K1, K2, Km, Kmax, ISV, IVA, KI, CKI, IHA, IHD, Rmin, KISA% ve IS gibi parametreler kaydedildi ve istatistiksel olarak değerlendirildi. Bulgular: Hastaların yaş ortalaması 45,48 ± 14,17 yıldı. Keratokonus indekslerinin çoğu normal sınırlar içinde kaldı; ancak ISV (35,07 ± 31,85), IHA (8,49 ± 11,02) ve KISA% (22,24 ± 25,49) geniş bir aralık gösterdi. pterjium evresi arttıkça yaş ve astigmatizma (p=0.03, p<0.001) ve görme düzeyi azalmaktadır (p<0.001). Ortalama keratokmetri değerindeki değişim ve en ince kornea kalınlığındaki azalma anlamlı değildi. Evre 3 pterjiumda, ISV, IHA, IHD, Rmin, KISA, indekslerinde anlamlı artış saptanırken, IVA, IS, KI de anlamlı azalma saptandı. Sonuç: Pterjium ektatik değişikliklere neden olmasa da, belirli keratokonus endekslerinde yansıyan önemli lokal kornea yüzey düzensizliklerine yol açabilir. Kantitatif topografik analiz, pterjiumun görsel etkisinin anlaşılmasına ve cerrahi planlamaya rehberlik etmeye yardımcı olabilir.

Keywords

• Pterjiyum
• keratokonus indeksleri
• korneal topografi
• keratometri

Examination of Topographic Keratoconus Indices in Pterygium

Abstract

Background: This study aimed to evaluate alterations in topographic keratoconus indices in eyes with pterygium and to assess the effect of pterygium on corneal morphology. Materials and Methods: A total of 78 eyes from patients diagnosed with pterygium were included in this study. Best-corrected visual acuity (BCVA) and slit-lamp biomicroscopy were performed. Patients were categorized into three groups according to the stage of pterygium. Scheimpflug-based corneal tomogra-phy was used to assess the following parameters: K1, K2, Km, Kmax, ISV, IVA, KI, CKI, IHA, IHD, Rmin, KISA%, and IS. All data were statistically analyzed. Results: The mean age of the patients was 45.48 ± 14.17 years. While most keratoconus indices re-mained within normal limits, ISV (35.07 ± 31.85), IHA (8.49 ± 11.02), and KISA% (22.24 ± 25.49) demon-strated considerable variability. With advancing pterygium stage, both age and refractive astigmatism increased (p = 0.03, p < 0.001), whereas BCVA significantly decreased (p < 0.001). Changes in mean keratometry and minimum corneal thickness were not statistically significant. In stage 3 pterygium, ISV, IHA, IHD, Rmin, and KISA% significantly increased, while IVA, IS, and KI significantly decreased. Conclusions: Although pterygium does not induce true ectatic changes, it may cause localized corneal surface irregularities that are reflected in certain keratoconus indices. Quantitative topographic assess-ment can enhance our understanding of the visual impact of pterygium and assist in preoperative plan-ning.

Keywords

• Pterygium
• keratoconus indices
• corneal topography
• keratometry

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