Turkiye Klinikleri Journal of Ophthalmology

.: ORIGINAL RESEARCH
The Comparison of Peripheral Corneal Stromal Demarcation Line Depth Percentages After Standard and Accelerated Collagen Crosslinking
Periferal Korneal Stromal Demarkasyon Hat Derinliği Yüzdelerinin Standard ve Hızlandırılmış Kollajen Çapraz Bağlama Sonrası Kıyaslanması
Ayşe ÇİÇEKa, Mustafa ATAŞa, Döndü Melek ULUSOYa, Necati DURUa, Süleyman DEMİRCANa
aKayseri Training and Research Hospital, Clinic of Opthalmology, Kayseri, TURKEY
Turkiye Klinikleri J Ophthalmol. 2020;29(2):129-35
doi: 10.5336/ophthal.2019-70114
Article Language: EN
Full Text
ABSTRACT
 Objective: To assess the effectiveness of accelerated cross-linking (CXL) on cornea periphery by comparing stromal demarcation line (SDL) depths in accelerated CXL with conventional CXL. Material and Methods: Patients with progressive keratoconus who were applied conventional 30 minutes CXL with 3 mW/cm2 (conventional group) or accelerated 10 minutes CXL with 9 mW/cm2 (accelerated group) were involved in the study. The SDL was measured in central and 3 mm periphery at the postoperative first month by using anterior segment optical coherence tomography. The SDL in the periphery was calculated as the proportion of central for each group seperately (SDL in the periphery/SDL in the central*100). The proportions were compared between two groups. Results: The mean central SDL depths in conventional and standard group were 302±49 μm and 251±42 μm, respectively (p: 0.004). The mean SDL percentages at 3-mm periphery ( superior, inferior, temporal, nazal) in conventional group were 84±14, 76±18, 77±12 ve 71±12, respectively. The same measurements in accelerated group were 74±12, 76±08, 70±12 and 70±12, respectively. Apart from the superior peripheral cornea there was no difference between two groups (p: 0.079). The SDL percentage at superior cornea was lower in accelerated group compared to conventional group (p: 0.044). Conclusion: The SDL percentage at superior cornea is lower in accelerated group compared to conventional group. It is a convenient advice to think again while deciding application of accelerated CXL in conditions effecting superior cornea.

Keywords: Collagen cross-linking; stromal demarcation line; anterior segment optical coherence tomography
ÖZET
 Amaç: Standard ve hızladırılmış protokol kollajen çapraz bağlama (KÇB) tedavisi sonrası santral ve periferik stromal demarkasyon hat (SDH) derinliğini kıyaslayıp hızlandırılmış protokolün kornea periferindeki etkinliğini değerlendirmek. Gereç ve Yöntemler: Otuz dakika boyunca 3 mW/cm2 dozunda standard protokol (standard grup) veya 10 dakika boyunca 9 mW/cm2 dozunda hızlandırılmış protokol (hızlandırılmış grup) KÇB uygulanmış ilerleyici keratokonus hastalığı olan kişiler çalışmaya dâhil edildi. SDH santral ve 3 mm periferden ön segment optik koherens tomografi kullanılarak postoperatif birinci ayda ölçüldü. Perifer SDH santralin yüzdesi şeklinde her grup için hesaplandı (perifer SDH/ santral SDH* 100). Yüzdeler iki grup arasında kıyaslandı. Bulgular: Çalışmaya 26 hastanın 42 gözü dâhil edildi, 38 gözde SDH gözlenebildi. (Bunlardan 18'i standard grup, 20'si hızlandırılmış gruptaydı). Standard ve hızlandırılmış grupta santral SDH derinliği sırasıyla 302±49 μm ve 251±42 μm idi (p=0,004). Üç mm periferden (üst, alt, temporal, nazal) ölçülen ortalama SDH yüzdeleri standard grupta sırasıyla 84±14, 76±18, 77±12 ve 71±12 idi. Aynı ölçümler hızlandırılmış grupta sırasıyla 74±12, 76±08, 70±12 ve 70±12 idi. Üst bölge hariç iki grup arasında fark yoktu (p>0,05). Üst korneada SDH yüzdesi hızlandırılmış grupta Standard gruba kıyasla daha düşük bulundu (p= 0,044). Sonuç: Üst korneada SDH yüzdesel olarak hızlandırılmış grupta standard gruba kıyasla daha düşüktür. Klinik uygulamalarda korneanın üst bölgesini etkileyen durumlar için KÇB tedavisi yapılacak hastalarda hızlandırılmış protokol uygulama kararı alırken tekrar düşünülmesi yerinde olacaktır.

Anahtar Kelimeler: Kollajen çapraz bağlama; stromal demarkasyon hattı; ön segment optik koherens tomografi
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