• Volume 2,Issue 4,2009 Table of Contents
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    • >Scientific Hypothesis
    • Role of psychological stress and the hypothalamicpituitary -adrenal axis in the pathophysiology of central serous chorioretinopathy

      2009, 2(4):283-285.

      Abstract (1169) HTML (0) PDF 194.22 K (951) Comment (0) Favorites

      Abstract:Central serous chorioretinopathy (CSC) is characterized by serous detachment of the sensory retina as a consequence of the focal leakage of fluid from the choriocapillaries to subretinal space through a defect of the retinal pigment epithelium (RPE). The exact cause of CSC has not well unknown. Psychological stress is thought to contribute to CSC, but the physiologic mechanisms are unclear. It is hypothesized that psychological stress can induce CSC through the mechanism of the hypothalamic-pituitary-adrenal (HPA) system. Psychological stress can adversely affect HPA axis and causes glucocorticoid levels to elevate. Increased glucocorticoids constrict choroid vessels, which leads to ischemia of choroids and damage vascular endothelial cells, thus causing vasopermeability to increase. RPE dysfunction will occur as a result of abnormalities in the choroidal circulation. The large molecules including protein may enter the subretinal space through the damaged vessels and RPE.

    • >Basic Research
    • Anti cataract potential of phyllanthus niruri in galactose induced cataractogenesis of rat

      2009, 2(4):286-290.

      Abstract (1620) HTML (0) PDF 438.15 K (1227) Comment (0) Favorites

      Abstract:AIM: To evaluate anti cataract effect of phyllanthus niruri (PN) both in vitro and in vino galactose induced cataract. METHODS: Aqueous extract of PN was evaluated against galactose-induced cataract both in vitro and in vivo. Galactosaemic cataract was induced in rats by feeding 300g/L galactose diet. PN was administered orally at three-dose levels 75, 150 and 300mg/kg of body weight. Rat lenses were subjected to osmotic stress in vitro by incorporating galactose (30mmol/L) in the culture medium. The effect of PN (720 and 880ug/mL) on the glutathione (GSH) and polyols levels was studied. RESULTS: PN significantly delayed the onset and progression of cataract in vivo. In addition to the delay in reaching various stages of development of cataract, stage IV did not develop with lower doses till the completion of experimental period. Lenses treated with PN 880ug/mL concentration showed higher levels of GSH and decreased levels of polyols in vitro.In vivo , 75mg/kg significantly delayed the onset and progression of cataract as compared to control. CONCLUSION: Phyllanthus niruri delays the process of cataracto-genesis in the experimental models. However, further study is required to extrapolate the use in human beings for the prevention of cataract.

    • Gel and porous polyethylene implants for anophthalmic cavity reconstruction-evaluation using the B scan ultrasound

      2009, 2(4):291-293.

      Abstract (1302) HTML (0) PDF 248.80 K (814) Comment (0) Favorites

      Abstract:AIM: To evaluate the host response of the gel and porous polyethylene implants in anophthalmic cavities using the B scan ultrasound. METHODS: Thirty-six white rabbits underwent unilateral enucleation with placement of gel or porous polyethylene spheres implants. The animals were submitted to clinical examination weekly and to ultrasound evaluation on 30, 60 and 90 days after surgery. RESULTS: All rabbits with gel polyethylene spheres, except one, showed implant extrusion probably because the gel spheres have hydrated and increased in volume. The B ultrasound of the gel polyethylene implant did not show vessels inside during the following period. Five animals (27.8%) with porous polyethylene spheres presented implant extrusion after 30 days of surgery. According to B ultrasound, the porous polyethylene implant showed irregular and heterogeneous architecture and reflective peaks similar to vascularized tissues. CONCLUSION: More studies are required to determine the ideal volume of gel polyethylene implant necessary to correct the diminished orbital content in the anophthalmic cavity. The B ultrasound effectiveness showed in this study for anophthalmic socket implants evaluation provides useful information for further in vivo studies and might substitute expensive methods of implants vascularization evaluation.

    • Inhibitory effect of captopril on retinal neovascularization in mice

      2009, 2(4):294-297.

      Abstract (1164) HTML (0) PDF 569.08 K (824) Comment (0) Favorites

      Abstract:AIM: To study the inhibitory effect of captopril on retinal neovascularization (RNV). METHODS: Sixty seven-day-old mice were randomly divided into treated group and control group with thirty mice in each group. These mice were exposed to 750 ± 50mL/L oxygen for 5 days and then to room air. The treated group had been injected captopril (2.7mL/kg), while control group had been injected 9g/L sodium chloride (2.7mL/kg) by intravitreal for 5 days. The mice were sacrificed at the 17th day after birth and the eyes were enucleated. Adenosine diphosphate-ase (ADPase) stained retina flat-mounts was performed to assess the retinal vascular profiles, Hematoxylin Eosin (HE) staining method was applied to count the number of new vascular cell nuclei and the expression of matrix metalloproteinase-2 (MMP-2) and pigment epithelium derived factor (PEDF) was detected by immunohistochemical method. · RESULTS: Comparing with control group, regular distributions, good branch and reduced density of RNV were observed in the treated group. The number of nucleus of new vessels vascular endothelial cells breaking through the internal limiting membrane was less in the treated group than in the control group ( <0.05). Stain of retinal MMP-2 was weaker in the treated group than in the control group and stain of retinal PEDF was stronger in the treated group than in the control group. CONCLUSION: Intravitreal injection of captopril (2.7mL/kg) may block the RNV in the oxygen-induced mouse model and the method may provide an effective method for preventing RNV.

    • Effect of fetal bovine serum on the proliferation and differentiation of murine corneal epithelial cells in vitro

      2009, 2(4):298-301.

      Abstract (1610) HTML (0) PDF 418.77 K (1071) Comment (0) Favorites

      Abstract:AIM: To investigate the effect of fetal bovine serum (FBS) on the proliferation and differentiation of murine corneal epithelial cells in vitro . METHODS: Mouse corneal epithelial cells (MCEs) were cultured in serum-free low-Ca2+ medium (KSFM) and KSFM supplemented with 100mL/L FBS, respectively. Population doublings (PDs) were determined. The expressions of corneal epithelial cell markers p63, keratin 19 (K19) and involucrin were investigated by RT-PCR and Western blotting analyses. RESULTS: Cells in KSFM were stably subcultured over 25 passages; however, none of the cell lines could pass P3 in KSFM with FBS. In KSFM, the cells showed typical cobblestone appearance and expressed p63, K19 and involucrin. After medium was supplemented with FBS, cells became homogeneous, large and squamous. Furthermore, both RT-PCR and Western blotting analyses showed that the expression of involucrin was increased significantly. CONCLUSION: FBS has effects of inhibiting proliferation and triggering differentiation of MCEs.

    • Quantitative detection of the expression level of transforming growth factor -βand its receptors in pterygium with RT- PCR

      2009, 2(4):302-305.

      Abstract (1094) HTML (0) PDF 187.67 K (765) Comment (0) Favorites

      Abstract:AIM: To quantitatively investigate transforming growth factor-β (TGF-β ) and its receptors in normal bulbar conjunctival tissues and pterygiumtissues. · METHODS: Thirty cases of pterygium patients were randomly selected to undergo surgical resection of pterygium lesion, and the normal margin of bulbar conjunctival tissues were collected as control. Gene expression was detected quantitatively by the method of quantitative real-time PCR (QRT-PCR) analysis. ·RESULTS: The expression level of TGF-β 1 and TGF-β 2 was 4.26×10-7±1.45×10-7 and 1.08×10-10±0.68×10-10 in normal bulbar conjunctival tissues, while 10.67 ×10-7 ±7.47 ×10-7 and 8.23 ×10-11 ±6.63 ×10-11 in pterygium tissues. The expression level of TGF-β RI and TGF-β RII was 0.003015±0.0036 and 5.33 ×10-5 ±5.05 ×10-5 in normal bulbar conjunctival tissues, while 0.000379 ±0.000281 and 1.002 ×10-5 ±9.04 ×10-6 in pterygium tissues. The expression level of TGF-β 1 and TGF-β 2 in pterygium was elevated ( P<0.01). TGF-β 1 expression level in pterygium increase 2.9±2.8 times than in normal conjunctiva. TGF-β 2 expression level in pterygium increase 7.5 ±1.4 times than in normal conjunctiva. The expression level of TGF-β RI in pterygium was significantly lower ( P<0.05). The expression level of TGF-β RII in pterygiumwas significantly lower (P<0.01). ·CONCLUSION: QRT-PCR is an effective method to quantitatively detect gene expression in eye. The upregulation of TGF-β 1 and TGF-β 2 and down-regulation of their receptors expression may play an important role in the pathogenesis of pterygium, which is noteworthy further investigation in diagnosis and treatment of pterygium."

    • N -acetylcysteine and Taurine inhibit hyperoxia - induced cataract in rabbit lens

      2009, 2(4):306-309.

      Abstract (1347) HTML (0) PDF 466.43 K (896) Comment (0) Favorites

      Abstract:AIM: To investigate the efficacy of N-acetylcysteine (NAC) and Taurine (Tau) in preventing hyperoxia-induced the lens opacification and the changes of biochemical parameters on organ cultured rabbit lenses. METHODS: Twenty-four lenses from adult rabbits were divided into the control group, the hyperoxia-exposed group, the hyperoxia-exposed group containing 20mmol/L of NAC, the hyperoxia-exposed group containing 80mmol/L of Tau, respectively. The treated groups incubated with hyperoxia (PO2 >80%) for 4 hours per day throughout a 7-day period. Lens transparency, histology and enzymatic activities measurements were determined after this incubation. RESULTS: Gross morphological examination of these lenses revealed some severe cortical opacification in the hyperoxia-exposed group, moderate cortical opacification in the control group and the Tau treated group. There was minimal cortical opacification in the NAC treated group. The glutathione (GSH) content and the activity of Na, K-ATPase were significantly decreased in the hyperoxia-exposed group than that of the control group, by 37.8% ( P<0.05) and 53.5% ( P<0.05), respectively. However, they were increased in the two treated groups, especially in the NAC treated group. There were no significant differences in the water-soluble protein content and the catalase and GSH reductase activities in all group lenses. CONCLUSION: Hyperoxia can induce the cortical opacification in the lens. The role of NAC in the prevention of hyperoxia-induced cataract is superior to Tau.

    • Implantation of modified poly 2 -hydroxyethy methacrylate -Polymethyl methacrylate Keratopro - stheses in rabbit and monkey corneas

      2009, 2(4):310-315.

      Abstract (1040) HTML (0) PDF 636.36 K (816) Comment (0) Favorites

      Abstract:AIM: To investigate the bio-colonization of poly 2-hydroxyethy methacrylate (PHEMA) sponge with cornea tissue and evaluate the therapeutic effects of modified porous poly 2-hydroxyethy methacrylate-Polymethyl methacrylate (PHEMA-PMMA) Keratoprostheses (KPro) on rabbit and monkey corneas. METHODS: The KPro were made using two-stage polymerization combined with mechanical cutting. The experiments were divided into two groups. In the control group, ten normal rabbit eyes received lamellar implantation of PHEMA sponges. The sponges were obtained 2 weeks, 1, 2, 3 and 4 months after operation. The cell proliferation and neovascularization inside the sponges were observed using light and transmission electron microscopy (TEM) and immunohistochemistry. In the experimental group, the porous PHEMA-PMMA KPros were inserted into the lamellar pockets of eight rabbit corneas and two monkey corneas (stage I operation). The healing process was investigated by slit-lamp microscopy. The anterior lamellar cornea tissues were removed 3 months after surgery, exposing the underneath transparent core (stage II operation). The operated eyes were then followed up for 3-6 months. RESULTS: No complications were observed in the control group. Under the light microscope, fibroblasts started to grow into the cornea 2 weeks after operation; lots of cells, accompanied with new blood vessels, invaded into the cornea 2-3 months after surgery. Invading cells of sponge, as well as keratocytes, were positive for vimentin. Under the electron microscope, the invading cells looked healthy and were surrounded by extracellular matrix and collagen. In eight rabbit eyes which received KPro implantation, anterior lamellar cornea melting happened in two eyes after the stage II operation. The remaining six corneas retained their central cores during observation after the stage II operation. Two operated monkey eyes were found no complication throughout the whole follow-up. CONCLUSION: The PHEMA sponge can obtain a tight fusion with the host cornea. The modified PHEMA-PMMA KPros have obtained relatively stable results after implantation into animal corneas. "

    • Quantitative detection of the expression level of transforming growth factor -β1 and -β2 in rat retina with real time PCR

      2009, 2(4):316-319.

      Abstract (1295) HTML (0) PDF 544.15 K (827) Comment (0) Favorites

      Abstract:AIM: To quantitatively detect the expression level of transforming growth factor-β1 (TGF-β1) and transforming growth factor-β2 (TGF-β2) genes in the retina of normal rat in order to determine the expression difference of TGF-β1 and TGF-β2 in retina. METHODS: The total RNA was isolated from which the first strand of cDNA was prepared. The mRNA levels of TGF-β1 and TGF-β2 were detected quantitatively by real time polymerase chain reaction (PCR). RESULTS: The mRNA levels of TGF-β1 and TGF-β2 were 0.0008±0.0003 and 0.0378±0.009, respectively. Expression of TGF-β2 was obviously higher than that of TGF-β1 in rat retina with statistical significance (t =12.37, P <0.001).The ratio of TGF-β2/TGF-β1 was 55.00±26.61. CONCLUSION: Quantitative reverse transcription polymerase chain reaction (QRT-PCR) can specifically and accurately detect gene expression level in rat retina. In retina the TGF-β2 gene is expressed more abundantly than TGF-β1. It is suggested that TGF-β2 play an important role in retina diseases.

    • Effects of naringenin on ocular blood flow and choroidal neovascularization in experimental animals

      2009, 2(4):320-323.

      Abstract (1433) HTML (0) PDF 406.61 K (894) Comment (0) Favorites

      Abstract:AIM: To investigate the effects of naringenin on laser- induced experimental choroidal neovascularization (CNV) in rat models, ocular blood flow and retinal function recovery after ischemic insults in rat eyes. METHODS: Male Brown Norway rats were treated to break the Bruch's membrane. Naringenin 10g/L (20mg/kg) was given once per day through intraperitoneal injection for 4 weeks after laser treatment. The development of CNV was determined by fluorescein angiography (FA) performed on week 2 and 4. The colored microsphere technique and electroretinography method were used for the study of ocular blood flow and retinal function recovery, respectively. RESULTS: The choroidal blood flow in elevated intraocular pressure (IOP) rabbit eyes was significantly increased by 10g/L naringenin solution as compared to control group (P < 0.05). The retinal function recovery after ischemic insults in rat eyes indicated significant increase of b-wave recovery in treated group, as compared to control group (P <0.05). The intensity of fluorescein leakage from the photocoagulated lesions significantly decreased in treated group, compared to the control group (75.8%-95.0%, P <0.01). CONCLUSION: Naringenin could prevent the development of CNV on laser-induced experimental rat models, increase the choroidal blood flow in elevated IOP rabbit eyes and be beneficial on retinal function recovery in ischemic rat eyes.

    • Effects of hydralazine on ocular blood flow and laser-induced choroidal neovascularization

      2009, 2(4):324-327.

      Abstract (1910) HTML (0) PDF 633.43 K (1130) Comment (0) Favorites

      Abstract:AIM: To investigate the effect of hydralazine on choroidal blood flow in rabbits and laser-induced choroidal neovascularization (CNV) in rats and on tube formation of human umbilical vein endothelial cells (HUVEC). METHODS: Female New Zealand white rabbits were used with raised intraocular pressure (IOP) of the left eye to 40mmHg. Hydralazine (10g/L) eye drops were instilled and ocular blood flow was measured with colored microspheres technique. Male Brown Norway rats were treated with Nd:YAG laser to break Bruch's membrane. Hydralazine (5, 10, 20g/L) eye drops or saline alone was instilled three times a day for 4 weeks after laser treatment. Fluorescein angiography (FA) and choroidal flat mount were used to measure the area of CNV. Tube formation of HUVEC was studied at different concentrations of hydralazine. RESULTS: With raised IOP to 40mmHg on rabbits, 10g/L hydralazine eye drops enhanced the choroidal blood flow significantly at 30 and 60 minutes after drug instillation. After 4 weeks of drug treatment, 5, 10 and 20g/L hydralazine eye drops all reduced the CNV formation dramatically measured by fluorescein angiography and choroidal flat mount. When HUVEC was cultured on matrix gel for 48 hours, the tube formation of HUVEC were prevented.by hydralazine at 3-30mg /L. CONCLUSION: Hydralazine prevents CNV formation in vivo and HUVEC tube formation in vitro, and enhances rabbits' choroidal blood flow after ischemia. It is hoped that hydralazine could be used to treat age-related macular degeneration in the future.

    • Preliminary findings of immunological characteristics in primary human corneal endothelial cells

      2009, 2(4):328-330.

      Abstract (1292) HTML (0) PDF 186.22 K (909) Comment (0) Favorites

      Abstract:AIM: To evaluate the function of primary human corneal endothelial cells (HCEC) serving as immunological cells. METHODS: Expression of HLA-DP, -DQ, -DR, CD40, CD80, and CD86 was determined by immunohistochemical methods. Meanwhile, purified peripheral blood mononuclear cells(PBMC) were cocultured with primary HCEC which were pre-treated with and without γ -IFN respectively. The activation of lymphocytes was determined by FACS analysis. RESULTS: In coculture system, T lymphocyte was activated by primary HCEC, HLA-DP, -DQ, -DR and CD40 expression were increased by γ -IFN induction. Costimulatory molecular CD80 was shown on the endothelial cells. CONCLUSION: Primary HCEC are assumed to be involved in the corneal transplantation rejection process as potential antigen presenting cells (APC).

    • Optimization of culture medium for primary retinal pigment epithelium cells and investigation of medium effects on growth factor expression

      2009, 2(4):331-337.

      Abstract (1396) HTML (0) PDF 641.37 K (1020) Comment (0) Favorites

      Abstract:AIM: To optimize the conditions for in vitro culture of retinal pigment epithelium (RPE) cells, we characterized expressions of various growth factors in RPE cells, including tumor necrosis factor (TNF-α), vascular endothelial growth factor (VEGF), β fibroblast growth factor (βFGF), transforming growth factor β2 (TGFβ2), and interferon-γ (IFN-γ). We also studied expressions of caspase-3 under different concentrations of fetal bovine serum (FBS) with insulin- transferrin-sodium selenite (ITS) supplement. METHODS: First, we investigated if the expressions of TNF-α, VEGF, βFGF, TGFβ2, IFN-γ, and caspase-3 in FBS and ITS with of concentration. Second, we cultured primary RPE cells from eyes of forty C57 BL/6 mice in standard dulbecco's modified eagle's medium (DMEM) containing 20, 40, 100mL/L FBS and 20, 40, 100mL/L FBS together with 10g/L ITS. Immunohistochemical staining and cell counting were performed to verify the existence and growth condition of RPE cells. The expressions of TNF-α, VEGF, βFGF, TGFβ2 and IFN-γ were determined using cells and supernatant from passage-3 to -4 primary RPE cell after 48 hours of culture with RT-PCR and enzyme-linked immunosorbent assays (ELISA). The expression of casepase-3 was determined via Western blotting. The major outcome measurement was the expression level of growth factors in cultured RPE cells and the experiment design was to expose the RPE cells to different culture medium. RESULTS: TNF-α, VEGF, βFGF, TGFβ2, but not IFN-γ, were expressed and the expressions increased with concentration. No expression of the aforementioned genes was detected in presence of ITS. The primary cultures of RPE cells were successfully established. TNF-α, VEGF, βFGF, TGFβ2 (but no IFN-γ) and the active caspase-3 were detected in 20, 40, 100mL/L FBS or 20, 40, 100mL/L FBS combined with 10g/L ITS; the expressions were upregulated with increasing concentration of FBS. There was no significant difference in the expression of growth factors between these groups. However, significant differences were shown among different concentration of FBS (P<0.01). The lowest expression was observed in 20mL/L FBS or 20mL/L FBS combined with 10g/L ITS medium with RPE cells. But RPE cells were shown in better growth condition in 20mL/L FBS combined with 10g/L ITS. CONCLUSION: TNF-α, VEGF, βFGF, TGFβ2 and caspase-3 are expressed in RPE cells and supernatants. The production of above 20mL/L FBS combined with 10g/L ITS in DMEM may be the ideal cell culture medium that supports the normal growth of RPE cells.

    • Injection of tissue plasminogen activator into the optic nerve in an animal model of retinal vein occlusion

      2009, 2(4):338-343.

      Abstract (1426) HTML (0) PDF 1.29 M (924) Comment (0) Favorites

      Abstract:AIM: To investigate the feasibility and efficacy of tissue plasminogen activator (tPA) injection into the optic nerve as a treatment for retinal vein occlusion in rabbits. METHODS: Rose Bengal-mediated laser-induced retinal vein occlusions were produced in rabbit eyes. Fluorescein angiography (FA) was performed on each eye 3 days before laser irradiation and 30 minutes after laser irradiation. The treatment group (n =20 veins) received intra-optic nerve injection of tPA (12.5μg in 0.05mL BSS) and the controls (n = 24 veins) received 0.05mL BSS. FA was repeated to determine the recanalization of the vessel at 3 and 7 days after treatment, followed by histological examination. RESULTS: Rose Bengal-mediated laser-induced retinal vein occlusions were successfully developed and confirmed by FA. The incidence of the recanalization of the vessels in treatment animals was 70.0%, while 16.7% in the control animals (P = 0.001). CONCLUSION: Intra-optic nerve tPA injection increases the incidence of recanalization of the occluded vessels. Although further studies are needed, our data suggested that injection of tPA into the optic nerve may have a potential benefit in the treatment of central retinal vein occlusion.

    • Electrophysiological evaluation of the safety of injection of tissue plasminogen activator into optic nerve in rabbits

      2009, 2(4):338-347.

      Abstract (1251) HTML (0) PDF 244.39 K (862) Comment (0) Favorites

      Abstract:AIM: To investigate the safety of tissue plasminogen activator (tPA) intra optic nerve injection in rabbits. METHODS: Group 1 and 2 (6 eyes in each group) received injection of tPA 25μg and 12.5μg in 0.1mL balanced saline solution (BSS). Group 3 (6 eyes) received injection of 0.1mL BSS. Six eyes in Group 4 as a normal control received no injection. The eyes were examined with slit lamp biomicroscope, indirect ophthalmoscope, visual evoked potentials (VEP) and electroretinography (ERG) at 1, 3, 7, 14 and 28 days after injection. RESULTS: No evidence of optic nerve or retinal toxicity or physical damage were revealed by ophthalmoscopy, VEP, and ERGs after the injection of tPA into the optic nerve. The means of the latency of the first peak of the VEP were 24.6±1.5, 24.1±1.9, 24.0±2.0 and 24.6±1.3mS respectively for the above specified groups (P =0.4112). The means of the amplitude of the first peak of the VEPs were 124±42, 145±41, 132±48 and 117±29μV respectively (P =0.0649). The means of the latency of a-waves were 6.0±0.4, 5.9±0.4, 5.9±0.5 and 5.8±0.3mS respectively (P =0.6279). The means of the amplitude of a-waves were 110±14, 112±15, 110±16 and 108?1μV respectively (P =0.7248). The means of the amplitude of b-waves were 151±12, 148±14, 144±16 and 141?0μV respectively (P =0.0957). CONCLUSION: Injection of tPA upto 25μg in 0.1mL into optic nerve is well tolerated.

    • Neovascularization profile in rat allogenic penetrating keratoplasty

      2009, 2(4):348-351.

      Abstract (1352) HTML (0) PDF 434.72 K (786) Comment (0) Favorites

      Abstract:AIM: To observe the neovascularization process with no intervention in rat allogenic penetrating keratoplasty. METHODS: Allogenic penetrating keratoplasties were successfully performed in 34 female SPF SD rats with no intervention after operations. Corneal neovascularization (CNV) process was noted on day 4, 7, 15 and 30 with operating microscope. The vascular area surface was calculated using the formula C /12×3.14×[r 2-(r -I )2]. RESULTS: CNV was noted in 29 out of 34 rats (85%). Firstly, the new vessels distributed around the cornea like a brush then gradually extended towards the center. The vessels were distorted and massive with branched tails, they continued growing to reticulated veins in peak time then gradually atrophied. The average neovascularization area (SE) on day 4, 7, 15 and 30 was 11.8±3.5mm2, 18.5±4.0mm2,14.4±4.3mm2 and 6.0±1.8mm2, respectively and 12.7±1.9mm2 in total. The average percentage that new vessels accounting the whole cornea area (SE) was 30.8%±8.7%, 65.3%±12.8%, 59.4%±14.5%,36.2%±10.9% and 48.7%±6.4% in total. CONCLUSION: In rat allogenic penetrating keratoplasties without intervention, CNV presents on day 4 and reaches the maximum area on day 7. Then the vessels gradually atrophies, about 50% of the maximum area still remains on day 30.

    • Comparison of IOL master and ultrasound biomi - croscopy in anterior chamber depth measurement

      2009, 2(4):352-354.

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      Abstract:AIM: To compare the measurement of anterior chamber depth (ACD) inclusive of corneal thickness using intraocular lens (IOL) master and ultrasound biomicroscopy (UBM) and evaluate the repeatability of each method. METHODS: Two consecutive measurements of ACD were prospectively performed using IOL master and UBM in 60 eyes in 60 individuals. Mean values were compared using the paired t test. For each individual, ACD measurements was performed 5 times to estimate the repeatability of each method by a coefficient of variation (CV). RESULTS: The mean ACD was 2.95?.25mm with the IOL master and 2.96±0.22mm with the UBM. This difference was not statistically significant (P =0.631). The coefficient of variation (CV) was 0.56%±0.26% and 0.65%±0.36% in IOL master and UBM, respectively. CONCLUSION: The mean ACD of IOL master is the same as UBM. The repeatability of IOL master is better than UBM.

    • >Clinical Research
    • Topographic changes at the optic disc in 33 patients with primary open angle glaucoma

      2009, 2(4):355-358.

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      Abstract:AIM: To show frequency of progression and the progression at the optic disc in primary open angle glaucoma (POAG). METHODS: A total of 33 patients (66 eyes), 14 male and 19 female, aged 14 to 79 with POAG were imaged using the Heidelberg Retina Tomography II (HRT II) three or more times during follow-up periods of 6 years (2000-2006). Disc progression was determined by regression analysis of global and segmental changes in optic disc parameters. Every patient was tested by Octopus G1 once a year. Imaged optic disc parameters with scanning laser tomography were: rim area (ra), cup/disc (C/D), rim volume (rv), mean RNFL thickness (mRNFL). Imaged segments of the optic disc were global (G), temporal (T), temporal superior (TS), temporal inferior (TI), nasal (N), nasal superior (NS) and nasal inferior (NI). RESULTS: Global frequency of progression according to c/d ratio existed in 34 eyes (51%), but 32 eyes (48%) were without frequency of progression. Progression existed in 12 eyes (18%) in temporal, 7 eyes (10.6%) in TS, 14 eyes (21%) in TI, 8 eyes (12%) in N, 7 eyes (10.6%) in NS, and 13 eyes (20%) in NI segment. Without progression were 5 eyes (8%). CONCLUSION: Disc progression in our study is mostly in N and TI segments. Most frequently are stricken TI and NI, but most infrequently NS segment. Most sensitive parameter is c/d ratio. Segmental scanning is of importance in POAG progression analysis.

    • Corneal topography and hyperopia

      2009, 2(4):359-361.

      Abstract (1644) HTML (0) PDF 273.16 K (1050) Comment (0) Favorites

      Abstract:AIM: To evaluate Orbscan II corneal topography in hyperopic cases. METHODS: A retrospective, observational, consecutive, clinical case series in 295 eyes of hyperopic patients who undergo a LASIK evaluation. The information that was reviewed included age, sex of the patients and the Orbscan II corneal topographic maps. Refractive powers and the following test indices produced by Orbscan II were analyzed: keratometry, corneal diameter, pupil diameter and anterior chamber depth. · RESULTS: The total mean corneal thickness was 546.3±35.5μm. It was found; 547.3±38.4μm in 17-29 years old, 553.4±38.3μm in 30-44 years old and 546.2±29.3μm in older than 45 years old. The mean corneal thickness was found 551.5±35.9μm in female, and 542.6±34.7μm in male. The total mean depth of anterior chamber was 2.57±0.40mm and in 17-29 years old patients was 2.82±0.39mm. In 30- 44 years old patients was 2.49±0.39mm and in patients older than 45 years old was 2.37±0.40mm. The mean depth of anterior chamber was 2.53±0.40mm in female and 2.60±0.40mm in male. A reverse significant relation between corneal thickness and keratometry were found. Refractive error severity had a reverse correlation with depth of anterior chamber and a correlation with keratometry (P =0.061, r = 0.108).Corneal thickness had a reverse correlation with keratometry (P =0.005, r =0.160), and correlation with pupil diameter (P =0.013, r =0.144). · CONCLUSION: We provides a description and analysis of Orbscan II findings in hyperopic patients These show mean corneal thickness 546.3±35.5μm and anterior chamber depth 2.57±0.40mm in hyperopic patients.

    • Hospital -base epidemiology, risk factors and microbiological diagnosis of bacterial corneal ulcer

      2009, 2(4):362-366.

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      Abstract:AIM: To determine the predisposing factors, clinical and microbial characteristics of bacterial corneal ulcer. METHODS: Three hundred patients (300 eyes) of clinically suspected microbial corneal ulcer were included in the study. Data was collected through history and slit lamp examination. Using standard techniques, corneal scraping was performed. A portion of each scraping was examined by direct microscopy for the presence of bacteria, fungi and acanthamoeba by using 100g/L potassium hydroxideand also by Gramand staining. Another portion was inoculated directly on the surface of solid media such as blood agar, Mac-Conkey agar, chocolate agar and Sabouraud's agar. A bacterial corneal ulcer was defined as a suppurative corneal infiltrate and overlying epithelial defect associated with presence of bacteria on corneal scraping examination and cured with antibacterial therapy. RESULTS: Of the 300 patients, sixty were lost in follow up, they were excluded from study. Of the remaining 240, bacterial corneal ulcer was identified in 156 (65.0%) patients. The age of patients ranged from 14 to 74 (mean age of 48) years. Majority of them were male (102). Corneal localization of the ulcers was distributed as central in 96 (61.5%) patients and peripheral in 60 (38.5%) patients. Ulcer depth in 82 (52.6%) patients was less than 1/3 of corneal thickness. In 64 (41.0%) patients, anterior chamber inflammation was 1+ to 2+ Tyndall effect with 1+ to 2+ cells present. Bacteria were isolated in 125 (80.0%) patients from the corneal smears. Sixty-nine percent of isolated bacteria were Grams' positive, and 39% were Grams' negative. Gram negative bacteria were associated with severe anterior chamber inflammation (P =0.003) and depth more than 2/3 of cornea (P =0.001). The most frequent organism isolated was Staphylococcus aureus. Forty percent of patients had good visual outcome with visual acuity same or better than the level at admission. Among the others 60% patients, final outcome was poor. CONCLUSION: Bacterial corneal ulcer is aserious ocular infectious disease that remains a therapeutic challenge and vision threatening ocular condition. Rapid isolation of bacteria and treatment with intensive ocular antibiotics represent decisive steps in the management of such pathologies.

    • >Investigation
    • Ocular involvement in leprosy: a field study of 1 004 patients

      2009, 2(4):367-372.

      Abstract (1897) HTML (0) PDF 289.20 K (1210) Comment (0) Favorites

      Abstract:AIM: To determine the prevalence of ocular involvement and pattern of ocular morbidity in leprosy patients. METHODS: Leprosy patients were examined in their respective treatment centers by the ophthalmologist over a period of three years. After recording visual acuity, anterior segment was examined with torch light and magnifying loupe. Intraocular pressure was measured with Schiotz tonometer. Fundus was examined, after dilating pupils with tropicamide eye drops, with direct ophthalmoscope. RESULTS: Out of 1 004 patients examined, 530 were suffering from lepromatous leprosy, 413 from tuberculoid leprosy, 61 from borderline leprosy. Ocular lesions related to leprosy were noted in 606 (60.3%) patients. Corneal changes (81.1%) were the most frequently observed lesions followed by eyelid changes (42.1%). Potentially sight threatening lesions such as lagophthalmos (17.3%), corneal anaesthesia (36.1%), and iridocyclitis (14.7%) were seen in these patients. None of the patients showed any fundus changes related to leprosy. Cataract, not related to systemic disease, was noted in 177 (17.6%) leprosy patients. Blindness related to leprosy was seen in 169 (16.8%) patients; chronic iridocyclitis with its complications was the most common cause of blindness in these patients. CONCLUSION: Ocular involvement was seen in 60.3% of leprosy patients; corneal lesions being the most common. One or more potentially sight threatening lesions were seen in two-thirds of these patients. Blindness related to leprosy was seen in 16.8% of patients. Early referral of patients with eye problems and treatment of potentially sight threatening lesions and cataract will reduce the prevalence of blindness in leprosy patients.

    • >Review
    • Recent advances on the modified endostatin and ocular neovascularization

      2009, 2(4):373-376.

      Abstract (1434) HTML (0) PDF 217.16 K (852) Comment (0) Favorites

      Abstract:Endostatin (ES), the C-terminal fragment of collagen XVIII, is a potent angiogenesis inhibitor. At present, there are a large number of research papers on ES. It has already been on clinical stage Ⅱ and been widely used in inhibition of neovascularization (NV). However, how to improve the bioactivity of ES is still a matter of ongoing discussion. The objective of this review is to elucidate the relationship between the modified ES and ocular neovascualrization, and to discuss the superiority based on the structure modification. The structure can be changed either by covalent modification or by genetic mutation. It is proposed that the secondary structral ES enhance the anti-angiogenic activity. Studies on modified ES also shed light on our understanding of the molecular action mechanisms of ES. Modified ES may be exploited as a new angiogenesis inhibitor for therapeutic applications, in substitution of the native ES.

Editors-in-Chief: Yan-Nian Hui and Peter Wiedemann

Established in April, 2008

ISSN 2222-3959 print

ISSN 2227-4898 online

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