Trc 50

Patients with idiopathic MH (minimum diameter ≥ 650 μm) who underwent 23-gauge PPV with ILM peeling or ILM insertion at Beijing Tongren Hospital from November 2016 to September 2020 were collected. The comprehension ophthalmological examinations were completed at baseline, 1 and 4 months after the operation, including Snellen BCVA, slit-lamp testing on the anterior segment and lens status, fundus photography (fundus camera, TRC-50; Topcon, Tokyo, Japan), OCT (Cirrus high-definition OCT; Carl Zeiss, Dublin, CA, USA) and MP-3 (microperimeter MP-3; NIDEK, Gamagori, Japan). The research was approved by the Medical Ethics Committee of Beijing Tongren Hospital, Capital Medical University and adhered to the tenets of Declaration of Helsinki.

All study subjects received a comprehensive ophthalmic examination including a visual acuity assessment, measurements of intraocular pressure (IOP) and non-dilated refraction using an autorefractor (Topcon AT; Topcon Corp., Tokyo, Japan), and axial length using corneal touch A-scan ultrasonography (Model 820; Allergan-Humphrey, San Leandro, CA, USA). Color fundus photographs were also taken using a fundus camera TRC 50 (Topcon, Paramus, NJ, USA) or Nonmyd 7 (Kowa, Tokyo, Japan) to identify any retinal pathology following pupil dilation. Two retinal specialists (S.H. and M.K.) evaluated the clinical records, ocular measurements, and color fundus photographs to exclude those with a previous history of ocular surgery, decreased visual acuity in the absence of any pathological cause (amblyopia), or retinal/choroidal pathologies that could affect choroidal volume and distribution.

Comprehensive ophthalmic examinations were conducted in the Department of Ophthalmology at the Samsung Medical Center in Seoul, South Korea. Medical and ocular histories of the participants were taken and they underwent, visual acuity (VA) assessment, intraocular pressure measurement, non-cycloplegic refraction with an autorefractor (Topcon AT; Topcon Corp., Tokyo, Japan), and axial length measurement with A-scan ultrasonography (Model 820; Allergan-Humphrey, San Leandro, CA). After pupil dilation, color fundus photography was performed using a fundus camera (TRC 50, Topcon, Paramus, New Jersey, USA; or Nonmyd 7, Kowa, Tokyo, Japan). Two retinal specialists (S.H. and M.K.) evaluated the clinical records, ocular measurements, and color fundus photographs. Eyes with a previous history of ocular surgery or ocular conditions that may affect retinal thickness, such as severe cataract, glaucoma, epiretinal membrane, diabetic retinopathy, retinal vein occlusion, age-related macular degeneration, and pathologic myopia were excluded from the study.