Sains Malaysiana 53(9)(2024): 3097-3111

http://doi.org/10.17576/jsm-2024-5309-15

Analysis of Schlemm's Canal Measurement and Evaluation with Fourier-Domain Optical Coherence Tomography in Primary Open-Angle Glaucoma

(Analisis Pengukuran dan Penilaian Saluran Schlemm dengan Tomografi Koheren Optik Fourier-Domain dalam Glaukoma Sudut Terbuka Primer)

SUCIJANTI¹, ZHI LAN YUAN^1,*, YA LIANG¹, SUN HONG¹, LIU WEI GU¹ & SI ZHENLI²

¹Department of Ophthalmology, First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China

²Department of Ophthalmology, Nanjing Tongren Hospital, Nanjing, Jiangsu Province, China

Received: 18 November 2023/Accepted: 17 July 2024

Abstract

The most common cause of permanent vision loss or blindness in the world is glaucoma. Primary Open Angle Glaucoma (POAG) develops when the eye drainage canals clog over time, increasing intraocular pressure and damaging the optic nerve. In POAG, an ophthalmology examination usually shows an open anterior chamber and chronic, irreversible multifactorial optic neuropathy followed by central visual field loss. OCT is specifically employed to investigate the elasticity of tissue, particularly in Schlemm's canal. This study aims to analyzed the morphological parameters of Schlemm's canal among patients with POAG and normal healthy control. In this observational study, we included one hundred patients, among them 50 patients had POAG, and 50 healthy controls, and both eyes were assessed. We measured the study cohort's and the healthy cohort's eyes' elevated IOP and the Schlemm's canal cross-sectional area (CSA). RT-Vue OCT was used to analyze both eyes' temporal, superior, inferior, and nasal regions. The data were analyzed using both univariate and bivariate methods. The characteristics of the morphological measurement of Schlemm's canal results were similar to those of Kagemann et al. There was a significant difference between age and SC measurement, but no correlation was observed between SC measurement and IOP or visual acuity. OCT is a useful way to evaluate the morphological status of Schlemm Canal in glaucoma patients. The eyes with POAG had smaller Schlemm's Canal- CSA than the normal eyes. The Schlemm canal-CSA in Chinese people had no differences from that of peoples of other races.

Keywords: Glaucoma; intraocular pressure; OCT; Schlemm's canal; visual acuity

Abstrak

Penyebab paling biasa kehilangan penglihatan kekal atau buta di dunia adalah glaukoma. Glaukoma Sudut Terbuka Primer (POAG) berkembang apabila saluran saliran mata tersumbat dari masa ke masa, meningkatkan tekanan intraokular dan merosakkan saraf optik. Dalam POAG, pemeriksaan oftalmologi biasanya mendedahkan ruang anterior terbuka dan neuropati optik multifaktorial kronik yang tidak dapat dipulihkan diikuti dengan kehilangan medan penglihatan pusat. OCT digunakan secara khusus untuk mengkaji keanjalan tisu, terutamanya dalam saluran Schlemm. Kajian ini bertujuan untuk menganalisis parameter morfologi saluran Schlemm dalam kalangan pesakit POAG dan kawalan sihat normal. Dalam kajian pemerhatian ini, kami memasukkan seratus pesakit, antaranya 50 pesakit mempunyai POAG dan 50 kawalan sihat dengan kedua-dua mata telah dinilai. Kami mengukur IOP kohort kajian dan mata kohort yang sihat dan kawasan keratan rentas kanal Schlemm (CSA). RT-Vue OCT digunakan untuk menganalisis kawasan temporal kedua-dua mata, superior, inferior dan hidung. Data dianalisis menggunakan kaedah univariat dan bivariat. Ciri pengukuran morfologi hasil kanal Schlemm adalah serupa dengan ciri Kagemann et al. Terdapat perbezaan yang signifikan antara umur dan pengukuran SC, tetapi tiada korelasi diperhatikan antara pengukuran SC dan IOP atau ketajaman penglihatan. OCT adalah cara yang sesuai untuk menilai status morfologi kanal Schlemm pada pesakit glaukoma. Mata dengan POAG mempunyai Kanal Schlemm - CSA yang lebih kecil daripada mata biasa. Kanal Schlemm-CSA dalam kalangan kaum Cina tidak mempunyai perbezaan daripada kaum lain.

Kata kunci: Glaukoma; saluran Schlemm; ketajaman visual; OCT; tekanan intraokular

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*Corresponding author; email: zhilanyuan@vip.sina.com