Refractive Errors and Optical Biometry Parameters Associated with Tilted Disc Syndrome

Öz

Evaluation and comparison of optical biometry parametres of patients with tilted disc to myopia cases to elucidate the origin of astigmatism. Upon fundoscopic examination 22 right eyes with tilted disc (Group 1) and 21 right eyes with a refractive error of ≥-0,75 (Diopters=D) (Group 2), who were diagnosed between 2014 and 2016 were included. Refraction and optical biometry measurements were obtained and compared 30 minutes after instilling %1 cyclopentholate. The mean age (years) of Group 1 was 41.5±17.6, while it was 26.2±7.8 in group 2. The mean spherical equivalent (D) was -5.10±3.72 in group 1, and -2.81±3.29 in group 2 (p=0.047). The mean cylindrical power (D) was -2.43±1.96 in group 1, and -0.63±0.67 in group 2 (p=0.001). The best corrected visual accuities (logMAR) were significantly lower in group 1 (p=0.001). The mean axial length of group 1 was 25.96±1.47 mm, while in group 2 it was 24.56±1.51 mm (p=0.001). There were no significant differences between two groups regarding lens thickness, anterior chamber depth and keratometry values. The mean keratometric values (D) were; K1: 42.60±1.93 in group 1 and 43.03±1.56 in group 2; K2: 44.46±2.14 in group 1 and 44.03±1,54 in group 2. The mean central corneal thickness (micron) were significantly lower in group 1; 523.82±25.90 (group 1) and 552.10±36.76 (group2) (p=0.006). Considering the fact that the difference between the keratometric values among groups was not significant, we concluded that the link between astigmatism and tilted disc could be due to lenticular and/or retinal changes. 

Anahtar Kelimeler

• tilted disc,optical biometry,astigmatism

Tilte (Eğik) Disk Sendromunda Kırılma Kusuru ve Optik Biyometri Özellikleri

Öz

Tilte diskli olgulardaki optik biyometri ölçümlerinin, miyop olgularla karşılaştırılarak astigmatizma değerlerin kaynağının değerlendirilmesi.2014-2016 yılları arasında, fundus muayenesinde tilte disk saptanan 22 hastanın sağ gözü (Grup 1) ile -0,75 (Diyoptri=D) ve üzeri miyopik refraksiyon kusuru saptanan 21 hastanın sağ gözü (Grup 2) dahil edildi. %1’lik siklopentolat uygulamasından 30 dk. sonra, refraksiyon ve optik biyometri ölçümleri yapıldı. Grup 1 ve 2 için elde edilen veriler karşılaştırıldı. Grup 1’in ortalama yaşı (yıl) 41,5±17,6 iken, grup 2’nin 26,2±7,8 idi. Ortalama siferik değerler (D) grup 1’de -5,10±3,72, grup 2’de -2,81±3,29 saptandı (p=0,047). Ortalama silindirik değerler (D) grup 1’de -2,43±1,96, grup 2’de -0,63±0,67 idi (p=0,001). En iyi düzeltilmiş görme keskinliği (EİDGK) (logMAR) grup 1’de anlamlı düzeyde düşüktü (p=0,001). Ortalama aksiyel uzunluk grup1’de 25,96±1,47, grup 2’de ise 24,56±1,51 olarak bulundu (p=0,001). İki grup arasında lens kalınlığı, ön kamara derinliği ve keratometri değerleri (D) açısından anlamlı fark yoktu. Grup 1 K1 değerleri 42,60±1,93, grup 2 ise 43,03±1,56; grup 1 K2 değerleri 44,46±2,14, grup 2 ise 44,03±1,54 olarak bulundu. Ortalama merkezi kornea kalınlığı (mikron) grup 1’de anlamlı olarak düşüktü; 523,82±25,90’e, 552,10±36,76 (p=0,006). Astigmatizma ile eğik optik disk görünümü arasındaki ilişkinin, keratometri değerlerimize yansımamış olması nedeniyle, astigmatizmanın lense ve/veya retinaya bağlı farklılıklardan ortaya çıkabileceğini düşünüyoruz.

Anahtar Kelimeler

• tilte disk,optik biyometri,astigmatizma

Kaynakça

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