The Effect of Amniotic Membrane Graft on the Inhibition of Corneal Opacity After Traumatic Injury

PURPOSE: This study was performed to evaluate the effect of amniotic membrane graft on corneal opacity after traumatic penetrating injury. METHODS: Corneal penetrating wound was made, 6mm in length. A total of 60 rabbit eyes were divided into three groups: (1) applied with amniotic membrane (n=20); (2) applied with contact lens (n=20); (3) control (n=20). Corneal opacity was analyzed with photoslit microscopy finding, histopathological finding, and expression of alpha-smooth muscle actin. RESULTS: Grade of corneal opacity was lower in amniotic membrane applied group (p<0.05). Infiltration of the inflammatory cells and expression of alpha-smooth muscle actin were also lower in amniotic membrane applied group. Histological structures of stromal cells were more regular in amniotic membrane applied group. CONCLUSIONS: Amniotic membrane graft can be an effective therapeutic method for prevention of corneal opacity after trauma by inhibiting infiltration of the inflammatory cells, proliferation of stromal cell and wound contracture by fibroblasts.

Effects of Transforming Growth Factor-beta on Proliferation, Collagen synthesis, Migration and Metalloproteinase Secretion of Human Retinal Pigment Epithelial Cells

PURPOSE: This study was performed to evaluate the effect of TGF-beta on proliferation, collagen synthesis, migration, and matrix metalloproteinase (MMP) secretion of human RPE cells in vitro. METHODS: The cultured human RPE cells were treated with either TGF-beta1 or TGF-beta2 in concentrations of 0, 0.1, 1, 10 ng/ml respectively. The cell number was measured in 3, 6, 9 days, and the collagen synthesis and cell migration was measured. [3H]-thimidine uptake assay was done to evaluate the change of DNA synthesis. And the secretions of MMP1, MMP2, MMP3, MMP9, TIMP1 (tissue inhibitor of metalloproteinase), and TIMP2 were measured by electrophoresis and Western blot analysis. RESULTS: TGF-beta1 and TGF-beta2 significantly inhibited the proliferation of RPE cells in a concentration -and time-dependent manner (p<0.05). [3H]-thymidine uptake was decreased by TGF-beta1 and TGF-beta2 in a concentration-dependant manner. The collagen synthesis of RPE cells was significantly increased by high concentration of TGF-beta1 and TGF-beta 2. However, the migration of RPE cells was not affected by TGF-beta. As the concentration of TGF-beta1 and TGF-beta2 increased, the secretions of MMP1, MMP2, MMP3 and MMP9 decreased, while the secretion of TIMP1 and TIMP2 increased after 72 hours. CONCLUSIONS: These results suggest that the TGF-beta1 and TGF-beta2 may have critical effect on the development of PVR and provide clues to possible therapeutic solutions for controlling PVR process.

A Case of Benign Nonte ratoid Medulloepithelioma of the Optic Nerve Head

Medulloepithelioma(diktyoma) is a uncommon congenital tumor that is generally believed to arise from the embryonic neuroepithelium of the medullary tube. This tumor usually arises from the ciliary body epithelium. But medulloepitheliomas of the retina and optic nerve may also occur, although it is extremely rare, because the embryonal medullary epithelium that lines the optic vesicle is continuous with the epithelium lining the cavity of the optic nerve during the early embryonal period. The occurrence of medulloepithelioma of the optic nerve is exceptionally rare, with only a few cases have been previously reported. We report a first case of medulloep-ithelioma of the optic nerve head in Korea in a 5-year-old girl who presented with a poor vision and squint of the left eye.

The Effect of Intravitreal Injection of Retinoic Acid on Experimentally Induced Proliferative Vitreoretinopathy using Human Retinal Prgment Epithelium in Rabbits

The retinoic acid have been demonstrated to modulate the growth and differentiation of several cell types including retinal pigment epithelium.We evaluated the effect of intravitreal infection of retinoic acid on experimentally induced PVR using human retinal pigment epithelium in the rabbit. 35 eyes of rabbit were induced PVR by injecting of human retinal pigment epithelial cells and were divided into three groups; Control group, group 1(retinoic acid 0.05mg/0.1ml DMSO was injected) and group 2(retinoic acid 0.1mg/0.1ml DMSO was injected). The stages of PVR were observed on days 3, 7, 14 and 28. The mean PVR stage progressed in all three groups. The PVR stage in control group is lower than other groups on days 3 and the PVR stage in group 3 is higher than other groups on days 28. In conclusions, intravitreal injected retinoic acid cannot inhibit PVR proliferation on 0.05 and mg/0.1ml concentration and it had toxic effect on retina in 0.1mg/0.1ml concentration. This results may present the lower limit of concentration to use retinoic acid intravitreously.

The Effect of Retinoic Acid on Experimentally-Induced Proliferative Vitreoretinopathy in the Rabbit

The proliferative vitreoretinopathy was a complication followed by operation of rhegmatogenous retinal detachment. It was the mot, comon cause of a failure of retinal detachment surgery. It was characterized by the growth of cellular fibrous membrance in detached both retinal side and vitreous and also developed by giant retinal dialysis, posterior segmental trauma, excessive cryotherapy, endophthalmitis, retianl vascular disease. In order to prevent and treat of proliferative vitreoretinopathy, various methods of operation and drugs have been researched. We executed the experiment using the rabbit to observe the effect of retinoic acid that is known by inhibition of migration and proliferation of retinal pigment epithelial cell and fibroblast in vitro. With 121 eyes of rabbit, we induced the proliferative vitreoretinopathy by injecting of human retinal pigment epithelial cell, human fibroblast, and rabbit fibroblast into eyeball of rabbits. The extent of proliferative vitreoretinopathy was compaired by injecting those cells with the group that was injected by retinoic acid and control. The result was that in those cell groups, the extent of proliferative vitreoretinopathy was significantly higher in the rabbit fibroblast group than the other two groups(P<0.05). And in the groups that were injected retinoic acid, when subconjuctivaly injected(0.3mg/0.3ml), proliferative vitreoretinopathy was effectively suppressed and when intravitrealy injected (0.05mg/0.1ml), vitreoretinopathy was more increased than the control group. This result was probably caused by high concentration of retinoic acid in vitreous and further evaluation with various concentration of retinoic acid is needed. In conclusion, we recommend a rabbit fibroblast and subconjunctival injection of retinoic acid for the study on the suppressive effect of proliferative vitreoretinopathy.

The Effect of Nitric Oxide on Cultured Bovine Retinal Pigment Epithelial Cell

Nitric oxide (NO), a potencially toxic radical, is generally regarded as a multi-potent molecule to be implicated in a wide range of biological function. The presence of nitric oxide synthase(NOS) in the retina, the constitutive isoform in photoreceptor outer segments and and the inducible form in retinal pigment epithelial (RPE) cells, has been demonstrated. The effect of NO in retina has been studying mainly as neurotransmitter. Present study was undertaken to find the role of NO in cultured bovine retinal pigment epithelial cells. Cultured bovine retinal pigment epithelial cells were treated with various concentrations of NO generator, S-nitroso-N-acetyl-D, L-penicillamine (SNAP). The survival fractions were measured by MTT assay. The morphologic changes were observed with inverted phase contrast microscope and electron microscope. To evaluate the characteristics of cell death, cells were lysed for DNA extraction, and the agarose gel electrophoresis was done. NO brought a decrease in the survival fraction of cultured bovine retinal pigment epithelial cells as concentrations increased. At high concentrations, cells became sparse. Electron microscopic study showed destruction of nuclear membrane and chromatin condensation in 1 mM SNAP treated group. These findings were compatible with apoptotic cell death that was supported with DNA laddering pattern in agarose gel electrophoresis. NO can induce damage to retinal pigment epithelial cells, and damaged cells are destined to apoptotic cell death.

The Treatment of the Macular Holes with Specific Causative Factors by Removal of the Posterior Hyaloid Membrane during Total Vitrectomy

Total vitrectomy and removal of the posterior hyaloid membrane were done in 7 patients who were diagnosed as macular hole with specific causative factors. The causative factor of 2 patients is high myopia and of remainers is trauma. Of the 7 patients treated by removal of the posterior hyaloid membrane during total vitrectomy, 3 patients showed anatomical and functional success, 2 patients only the anatomical success, and 2 patients failure. The postoperative complications included phthisis bulbi, proliferative vitreoreinopathy, optic atrophy, and macular degeneration, and iatrogenic rhegmatogenous retinal detachment. Two patients of the 3 success cases complained of mild diplopia after operation.

A Case of Orbital Pseudotumor Associated with Periscleritis

Idiopathic orbital inflammation or pseudotumor is an inflammatory swellings of the orbital contents and has the false clinical impression of a neoplasm. Clinically, the disease can be further characterized according to which orbital structure is predominantly involved myositis, periscleritis, trochleitis, perineuritis and dacryoadenitis. The authors experienced a 22-year-old male patient who had complained of headache, proptosis, decreased visual acuity and ocular pain on his both eyes, 11 weeks before admission. According to orbital CT finding and ocular examination he was diagnosed as orbital pseudotumor associated with periscleritis. After the medical treatment his symptoms were significantly improved. In this article we present our case with a brief review of the literature related to orbital psudotumor.

Clinical Evaluation for Branch Retinal Vein Occlusion

It is known that branch retinal vein occlusion (BRVO) is related with systemic vascular diseases. From January 1987 to December 1990, we experienced 46 patients who were diagnosed as BRVO among 18,057 patients who visited eye department during the same period, We evaluated 29 patients of BRVO who were followed up over 1 year. The incidence of BRVO was 026%. Male were 11(38%) and female were 18(62%), and there were no significant difference in morbidity between male and female. The average age of affected patients was 5:3 years. The average distance between the disc margin and the site of occlusion was 0.86 disc diameter. The type of BRVO was non-sichemic in 18 patients and that of remainders was ischemic. Most common site of occlusion was the crossing between the first branch of artery and the first branch of vein. The most common systemic disease associated with BRVO was hypertension. The visual prognosis was not affected by the factors including the associated systemic diseases, the type of BRVO and the site of BRVO. However, there was a significant correlation (p

A Statistical Analysis of Ocular Injuries of Inpatients

The authors analysed 127 patients(130 eyes) with ocular injuries among 561 inpatients who had been admitted to Chung-Ang University Hospital during the period of 3 years from January 1986 to December 1988. 1. The incidence of ocular injuries was 22.6% of all inpatients. 2. The incidence was more common in male(91.3%) and in the age of second(40.1%) and third decade(20.5%). 3. The most common cause of ocular injuries was industrial acddent(34.6%), followed by fight(22.0%) and traffic accident(18.9%). 4. The ocular injuries commonly developed between 11 and 14 o'clock(29.9%). Especially, 43.2% of the industrial ocular injuries occurred at this time. 5. The most common causative agent of ocular injuries was broken glass pieces(26.8%), followed by metal(18.9%) and fist and foot(17.3%). 6. The most common nature of ocular injuries was eyeball perforation(53.0%), followed by hyphema(18.5%). 7. The expectancy of a good visual outcome were nonperforating injury, corneal laceration and absence of severe prolapse of intraocular tissue. 8. The most common complication was corneal opacity(58.7%).

A Study on Interrelationship of the Refractive Error and the Ocular Fundus Findings

In order to investigate the fundus fundings in myopic eyes and to clarify the correlation between the refractive error and the myopic fundus changes, 7968 eyes of school children with refractive error in Seoul were selected and the observation of ophthalmoscopic features of crescent of optic nerve, cup to disc(C/D) ratio and the spontaneous venous pulsation were attempted. The result of the study were summarized as follows: 1. The optic nerve crescent was counted in 2643 eyes(33.2%) among 7968 eyes and the temporal crescent was the most frequent localization(72.8%) in 2643 eyes. 2. The incidence of the optic nerve crescent was increased in proportion to the degree of myopia regardless of its localization type, however the incidence of the crescent was decreased at -7.0 D or higher myopes. 3. The mean horizontal C/D ratio was 0.24 +/- 0.13 and the C/D ratio of 0.4 or more were common in the myopia of -2.0 D or more. The correlation between the C/D ratio and the refractive error appeared statistically significant(p<0.05). 4. In most of eyes(98.6%), difference of the C/D ratio between right and left eye was 0.2 or less. 5. The spontaneous venous pulsation on the optic disc was observed in 594 of 7968 eyes(7.5%).

Survey on the Visual Impairments and Ocular Health Status in Urban School Students

As a partial effort of the survey in the National Plan for the Eye Health, the analysis of the visual impairment mainly refractive errors among 4,004 School Children in Seoul(1986) with the ancilliary questionnaire on various conditions was attempted. The number of the student with subnormal vision(0.7 or less) was 1,552(38.8 %), and this rate was increased with the higher school grade. Of the 2,551 eyes with subnormal vision(0.7 or less), the confirmed refractive errors consisted of myopia 2,170(78.7%), hyperopia 237(8.6%), and mixed astigmatism 144(5.2%) eyes. The number of glasses wearer among the students of vision 0.5 or below(1,129) was 770(63.2%), of which the under-corrected cases 380(49.3%) weregreater in number with the over corrected cases. The causes of not-wearing glasses in the students who belonged to the vision 0.5 or below indicated in prominence of numbers of 1) no complaints without glasses in 172(42.0%), 2) unwareness of the visual impairment in 77(20.0%), and 3) annoyance to wearing glasses in 51(13.4%), rather than economical reasons in 12(3.1%). The amblyopic components were estimated among 129 cases(3.2%) in combination of refractive errors. Further program to supply the glasses with appropriated prescription and the details on the practical aspects of related elements would be discussed.

A Case of Corneal Ulcer Caused by Paecilomyces in Diabetic Patient Wearing Soft Contact Lens

Fungal corneal ulcer is well known longstanding and troublesome disorder in eye clinic. Paecilomyces, a well known saprophytic fungi, is rarely pathogenic in normal humal being. Authors experienced a case of corneal ulcer caused by Paecilomyces in diabetic patient wearing soft contact lens, that was proved by Gram stain and Sabouraud agar culture. We report this as the first case of corneal ulcer caused by Paecilomyces in Korea.