Evaluation of the Effect of Inferior Oblique Myectomy on Corneal and Anterior Segment Parameters

Abstract

Purpose: This study aimed to evaluate the effect of inferior oblique myectomy (IOM) surgery on the cornea and anterior segment. Methods: The sheimpflug corneal topographies of 56 eyes of 33 patients who underwent IOM were analyzed at preoperative, postoperative 1 week, 1 month, 3 months, and 6 months. Astigmatism degree (Cyl), astigmatism axis (Ax), K1, central corneal thickness (CCT), anterior chamber depth (ACD), anterior chamber volume (ACV), iridocorneal angle (ICA), and horizontal visible iris diameter (HVID) were evaluated. Results: The mean corneal Cyl, K1, ICA, ACD, and HVID did not change after IOM (p=0.671, p=0.377, p=0.431, p=0.588, p=0.795, respectively). There was a statistically significant change in Ax (p=0.025). The right Ax decreased, and the left Ax increased the most at 1 month (p=0.025, p=0.882, respectively). Ax increase was also detected in the left eye that was not operated on. The mean CCT increased and mean ACV decreased at 1 month (p=0.588, p=0.270, respectively), but these changes returned to preoperative values at 3 months. Conclusion: The manifestation of anterior segment alterations and intorsion in both eyes following inferior oblique myectomy may contribute to diminished visual acuity and the potential onset of amblyopia. These alterations merit consideration during the assessment, and if deemed necessary, the provision of new spectacles should be considered as a preventive measure against anisometropic amblyopia.

Keywords

• inferior oblique myectomy
• cornea
• astigmatism
• anterior segment

İnferior Oblik Miyektominin Kornea Ve Ön Segment Üzerine Etkisinin Değerlendirilmesi

Abstract

Amaç: Çalışmamız inferior oblik miyektominin (İOM) kornea ve ön segment üzerine etkisini değerlendirmeyi amaçlamaktadır. Yöntem: Bu çalışmada İOM yapılan 33 hastanın 56 gözünün ameliyat öncesi, ameliyat sonrası 1. hafta, 1. ay, 3. ay ve 6. ay sheimpflug kornea topografileri incelendi. Astigmatizma derecesi (Cyl), astigmatizma aksı (Aks), K1, santral kornea kalınlığı (SKK), ön kamera derinliği (ÖKD), ön kamera volümü (ÖKV), iridokorneal açı (IKA) ve horizontal görünür iris çapı (HGİÇ) değerlendirildi. Bulgular: IOM sonrası ortalama kornea Cyl, K1, IKA, ÖKD ve HGİÇ değişmedi. (sırasıyla p=0,671, p=0,377, p=0,431, p=0,588, p=0,795). Cyl'de değişiklik olmamasına rağmen (p=0,671), Aks'ta değişiklik oldu (p=0,025). Sağ Ax düşüşü ve sol Ax artışı birinci ayda maksimumdu (sırasıyla p=0,025, p=0,882). Ayrıca ameliyat edilmeyen sol gözlerde dahi Aks artışı tespit edildi. Ortalama SKK 1. ayda arttı ve Ortalama ÖKV azaldı ve 3. ayda ameliyat öncesi değerlere döndü (sırasıyla p=0.588, p=0.270). Sonuç: İnferior oblik miyektomiyi takiben her iki gözdeki ön segment değişiklikleri ve intorsiyon, görme keskinliğinin azalmasına ve potansiyel ambliyopi başlangıcına katkıda bulunabilir. Gerekli görülmesi halinde anizometropik ambliyopiye karşı koruyucu bir önlem olarak yeni gözlükler yazılmalıdır.

Keywords

• inferior oblik miyektomi
• kornea
• astigmatizma
• ön segment

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