• Journal of the Optical Society of Korea
• /
• 제15권1호
• /
• pp.68-73
• /
• 2011

This study investigated, using the Orbscan II topography system, the influence of age and sex related changes on the corneal thickness and anterior corneal curvature, more specifically the fine structure of the cornea, in a Korean young population. The Orbscan II topography system is a computer-assisted slit-beam scanning technology that can map the anterior section of the cornea. The mean central corneal thickness of all subjects was $547.532{\pm}44.529\;{\mu}m$. There was no statistical difference (p>0.5) in the mean central corneal thickness between males and females. Sex and age related changes in the mean central corneal thickness had no specific statistical difference (P>0.5). There was a negative correlation between the anterior corneal curvature and the central corneal thickness in all subjects, except for the twenty year olds. However, the thickness relationship between the mean central corneal and the eight paracentral corneal thicknesses had strong statistical differences in all subjects. Also age and sex related changes in the central corneal thickness and the anterior corneal curvature in all subjects had no statistically significant difference, except from 20-26 years old (p>0.05). This information could be a suitable reference basis for future studies in the young population of Asia and for the development of examination tools for corneal refractive surgery.

• Applied Microscopy
• /
• 제44권3호
• /
• pp.88-95
• /
• 2014

This study examined the effects of quercetin on corneal opacity caused by corneal edema by suppressing the damage on corneal endothelial cell, which was induced by mitomycin-C (MMC). In the MMC-treated group, the number of keratocytes was noticeably fewer compared to that of other groups. Although this group showed normal amount of fiber in the corneal stroma, the thickness was shown to be very thick and the alignment of the corneal endothelial cells that worked as the barrier against aqueous humor was irregular. According to such results, it was known that corneal opacity induced by MMC is not caused by proliferation of keratocytes, but by corneal edema triggered by the infiltration of aqueous humor. In the MMC+quercetin and quercetin+MMC-treated groups, the number of keratocytes was higher and polymorphonuclear leukocytes infilteration was lower significantly compared to that of the MMC-treated group. Although the amounts of fiber and endothelioid cell arrangement were normal, there was more space observed in the corneal stroma. Nonetheless, these groups showed significantly lower stromal thickness compared to that of the MMC group. In conclusion, quercetin has the effect on the reduction of corneal opacity caused by corneal edema that work MMC-induced damage to the corneal endothelial cells.

• 한국임상수의학회지
• /
• 제37권4호
• /
• pp.213-216
• /
• 2020

Two cats were presented to the Dana Animal Hospital Eye Center and were diagnosed with corneal sequestrum through full ophthalmic examination. After lamellar keratectomy using a reusable corneal trephine blade and a crescent microsurgical knife, porcine urinary bladder submucosa extracellular matrix (UBM, ACeLL Vet^® corneal disc) was applied to the corneal defects. In both cases, no corneal sequestrum recurrences were observed until 119 days and 253 days after the surgery, respectively. Porcine UBM could be recommended as a surgical scaffold for treatment of corneal sequestrum in cats.

• 한국임상수의학회지
• /
• 제38권2호
• /
• pp.98-102
• /
• 2021

Three dogs with different extents of corneal edema were presented to the Dana Animal Hospital Eye Center. The dogs (3 eyes) were diagnosed with corneal endothelial degeneration with clinical signs of corneal edema, conjunctival hyperemia, and mild blepharospasm through a full ophthalmic examination. For the treatment of corneal edema, superficial keratectomy using a crescent microsurgical knife was performed, and a conjunctival advancement hood flap was applied to the stromal defects. In two cases where corneal edema and opacity were observed only in a part of the cornea, corneal edema was reduced and did not progress to other parts of the cornea and corneal transparency and vision were also well-maintained during the follow-up on days 349 and 231 after the surgery. In a case where the whole cornea was edematous and cloudy, corneal edema and opacity had not clearly improved at the last follow-up on day 275 after the surgery. In conclusion, SKCAHF relieved corneal edema and improved vision, and the prognosis tended to be better when there was less corneal edema caused by CED.

• 한국임상보건과학회지
• /
• 제7권1호
• /
• pp.1205-1214
• /
• 2019

Purpose: To investigate the effect of color soft contact lenses on the corneal thickness in young Korean population. Methods: The subjects consisted of 112 eyes (7 males, 49 females) with the mean age of $20.987{\pm}1.093years$ (range 20-25 years) in young Korean population during 2018. Test was compared the corneal thickness before and after wearing color soft contact lenses. The thinnest cornea thickness(TCT), central cornea thickness(CCT), pupil centre thickness(PCT), superior corneal thickness(SCT),inferior corneal thickness(ICT), medial corneal thickness(MCT), lateral corneal thickness(LCT) of the cornea was measured using the Pentacam pachymetry. The statistically analysis was perform the Shaparo-Wilk test. Results: The right eye was a statistically significant among the CCT,LCT, MCT and TCT values(p<0.001) in the compared the corneal thickness before and after wearing soft colour contact lenses. Also the left eye was a statistically significant among the LCT and MCT values(p<0.001) in the compared the corneal thickness before and after wearing soft colour contact lenses. However, there was no statistical difference (p>0.5) in the mean PCT between before and after wearing color soft contact lenses. Conclusion: These results suggested that the color soft contact lens wear can the effect the regional thickness of cornea. Therefore, the analysis of corneal topography with Pentacam can provide correct and useful diagnostic information of the morphology of the RGP contact lens fitting and diagnosis of corneal refraction surgery.

• Current Optics and Photonics
• /
• 제3권1호
• /
• pp.72-77
• /
• 2019

This study was performed to analyze the optical aberrations of the cornea induced by myopic refractive surgery. Corneal total higher-order aberrations, spherical aberration and coma for 4-mm and 6-mm pupils were measured using a wave-front analyzer. The amount of aberrations of the oblate corneal optics by the achieved correction was found to be larger than for the prolate corneal shape with complete eye, in an emmetropia control group. The change in corneal shape acts as an optical factor that degrades the quality of the retinal image; it seems to be one of the important factors related to quality of vision.

• 한국임상수의학회지
• /
• 제35권6호
• /
• pp.311-314
• /
• 2018

Squamous cell carcinoma (SCC) is a form of neoplasm that origins from the epithelial surface of many organs. Ocular occurrence in small animals is rare, especially in the central cornea without the involvement of limbus or conjunctiva. In the current case, a 10-year-old, spayed female Shih-Tzu was presented with a central corneal mass. Through an ophthalmic examination the sign of corneal scarring around the mass was found. Pink fleshy lesion that protruded outward was removed through superficial keratectomy. The mass with the size of $8.5{\times}6.5$ millimeter was histopathologically diagnosed as corneal SCC infiltrating not only the epithelium, but also the superficial corneal stroma with surrounding superficial lymphoplasmacytic and neutrophilic chronic keratitis. Also, the adjacent, non-affected corneal epithelium was markedly hyperplastic and keratinized; the adjacent stroma was moderately vascularized and fibrotic. The pulse-dose therapy using 1% topical 5-flourouracil were applied for five cycles. The tumor has not recurred through nine months of follow-up time.

• 한국안광학회지
• /
• 제14권2호
• /
• pp.35-39
• /
• 2009

목적: 본 연구는 각막지형검사기의 각막형상을 이용하여 각막수차를 구현하는 프로그램을 개발하고자 하며, 개발된 프로그램을 이용하여 저니케 다항식(Zernike Polynomial)으로 파면과 각막수차를 구현하고자 한다. 방법: 각막지형검사기인 ORBSCAN의 각막형상 데이터로부터 각막의 형상을 재구성하기 위해 저니케 다항식을 사용하였으며, 이때 동공의 유효구경은 6 mm를 고려하였다. 구현된 각막형상으로부터 광선추적을 사용하여 동일한 광학적 거리의 파면을 구현하는 프로그램을 개발하였으며, 파면으로부터 6차 28항의 저니케 계수로 각막수차를 구현하였다. 결론: 본 연구에서는 각막지형검사기의 각막형상으로부터 각막의 수차와 파면을 구현하는 프로그램을 개발하였으며, 이러한 결과는 각막지형검사기 개발과 콘택트렌즈 및 OK렌즈 처방에 유용하게 적용될 수 있으리라 사료된다.

• 한국안광학회지
• /
• 제19권3호
• /
• pp.377-382
• /
• 2014

목적: 전후면 각막난시와 전체 각막난시를 측정하고, 이들의 관계를 분석하여 후면 각막난시가 미치는 영향을 알아보았다. 방법: 각막굴절교정수술을 목적으로 방문한 22~28세의 31명(31안)을 대상으로 하였다. 각막질환이 있는 경우는 제외하였고, 회전 샤임플러그 카메라를 이용하여 수술 전에 전체 각막난시와 전후면 각막난시를 구분하여 측정하였다. 굴절력이 가장 큰 경선과 가장 작은 경선의 차이로 난시의 크기를 계산하였고, 가장 가파른 경선의 방향에 따라 직난시와 도난시로 분류하였다. 결과: 전체 각막난시와 전후면 난시의 평균은 $1.13{\pm}0.76D$, $1.51{\pm}0.84D$, 그리고 $-0.59{\pm}0.17D$ 였다. 후면 각막난시의 크기는 대상자들 모두 -1.0 D에서 -0.25 D에 분포하였고, 전체 각막난시의 크기를 100으로 봤을 때 전면 각막난시의 크기는 $142.9{\pm}29.9%$ 였다. 전체 각막난시는 전면난시의 크기와 가장 높은 상관성(y=0.871x-0.184, $R^2=0.982$)을 보였고, 후면 난시와는 높은 음의 상관성(y=-2.974x-0.184, $R^2=0.698$)을 보였다. 대상자들의 각막전면과 후면난시는 모두 직난시에 분류되었다. 결론: 20대 대상자의 전면과 후면 각막난시는 각각 0.2 D에서 -3.8 D, 그리고 -1.0 D에서 -0.25 D의 크기를 가졌고, 전면과 후면난시 모두 직난시의 비율이 높았다.

• 한국임상수의학회지
• /
• 제40권2호
• /
• pp.152-157
• /
• 2023

A two-year-old, spayed female, Bichon Frise, was referred for severe corneal edema and corneal ulcer in the left eye (OS). The cornea had gradually swelled over one week after phacoemulsification performed a month prior, and that was refractory to 5% sodium chloride eye drop instillation or temporary partial tarsorrhaphy. A complete ophthalmic examination was performed. Severe corneal edema with intrastromal bullae and moderate anterior chamber flare was found on slit-lamp biomicroscopy in the OS, which obstructed the fundus examination. Corneal thickness was measured using high-resolution ultrasound biomicroscopy. The thickness of the OS cornea was 2.74 mm. The "letter-box" conjunctival flap was planned. Dorsal and ventral superficial keratectomy followed by a hood conjunctival flap was performed. Topical and systemic antibiotics and 5% sodium chloride eye drops were prescribed. Decreased corneal thickness was observed at one week, two weeks, and two months postoperatively (1.53 mm, 1.32 mm, and 0.92 mm, respectively). There were no postoperative complications, such as ocular discomfort or recurrent corneal ulcers. The "letter-box" conjunctival flap, a type of superficial keratectomy and conjunctival advancement hood flap, effectively relieved the severe irreversible corneal edema. This could be a simple but effective surgical intervention for patients with endothelial cell damage especially after phacoemulsification.