Epidemiology of Glaucoma in Asia-Pacific

Primary open angle glaucoma is the second most important cause of permanent blindness in the Asia Pacific region. Thus it is very important to identify epidemiological and other risk factore which are associated with open angle glaucoma. The risk for glaucoma optic nerve damage increases with the age and with the level of the intraocular pressure. In this paper, I will highlight our study of several risk factors for development of the open angle glaucoma like (1) elevated intraocular pressure, (2) myopia, (3) suspicious large optic disc cup, (4) cupping with disc haemorrhages and (5) nerve fibre defect. The general and systemic conditions which are implicated as risk factore are (1)family history of glaucoma, (2)increase in age, (3)diabetes mellitus, (4) cardio vascular conditions like central retinal vein occlusion etc. (5) the endocrine disorders with increased thyroid and increased cortico steroids responsiveness in patients with glaucoma will be discussed.     

Advances in Management of Retinoblastoma

Retinobiastoma is a highly malignant intraocular tumor of children that requires accurate diagnosis to prompt treatment. This article reviewed clinical, pathological and follow-up data on 1 147 cases of retinobiastoma registered in Japan from 1975 to 1982. It is obvious that the prognosis of children with retinobiastoma has improved remarkably in recent years. The current advances in the management of the retinobiastoma were discussed.     

The evaluation of chosen cytokines in induction of ocular changes in Sjögren's syndrome of dry eye

PURPOSE: To evaluate the role of pro-inflammatory cytokines interleukin-8 (IL-8) and interferon-gamma (IFN-gamma) in pathogenesis of Sjogren's syndrome of dry eye (SS--dry eye), and in induction of ocular changes in this disease. MATERIAL AND METHODS: Tear samples were collected from 25 patients with Sjogren's syndrome of dry eye and 33 healthy volunteers. Cytokine levels were determined by ELISA. Ophthalmic examinations, including tests for dry eye, were used to study the ocular surface. The levels of these cytokines in tears and dry eye findings were compared. RESULTS: The tears level of IL-8 and IFN-gamma in SS--dry eye patients were significantly higher than those in controls. We found positive correlation between the tears levels of pro-inflammatory cytokines and dry eye findings (subjective and objective assessments and diagnostic tests). CONCLUSIONS: The elevated level of pro-inflammatory cytokines in tears fluid of patients with Sjogren's syndrome of dry eye may be important factor in the pathogenesis of this disease. Significant correlation between tears level of cytokines and dry eye findings suggest, that these cytokines induce inflammatory changes of ocular surface in Sjogren's syndrome of dry eye.     

mRNA Expression of Vimentin Gene in Lens of Transgenic Mouse and DNA Amplification in Human Cataracts

Purpose: To investigate the role of vimentin gene in cataractogenesis. Methods: The 12. 7kb chicken vimentin genes were microinjected into the male pronuclei of 918 fertilized mice eggs. 841 injected embryos were transferred into oviducts of pseudopregnant recipient females, of which 12 pregnant mice gave birth to 49 offsping mice. The integration and expression of exogenous gene in the offsping were analysed by Southern and Northern blot hybridizations. In the human senile cataract, the lens vimentin gene was analyzed with the chicken vimentin gene probe.Results: It showed that four of F1 offspring were transgenic mice in which the chicken vimentin gene was integrated in their genomes. The transgenic band was 12kb, similar to the 12. 7kb chicken vimentin fragment injected. One 2kb vimentin mRNA was visualized on E2 mouse lens blot, which revealed that the chicken vimentin gene was efficiently expressed in this transgenic mouse. In the human senile cataract lens, 12kb BamHI-restricted vimentin fragments     

Phacoemulsification in review: Optimization of cataract removal in an in vitro setting

Phacoemulsification, initially used in the late 1960s, continues to be the standard of care for cataract removal. An animal model was developed so that, in a controlled research setting, all the various machines, handpieces, tips, and settings could be investigated. As a general rule, the higher power, vacuum, and aspiration settings lead to optimally efficient phacoemulsification. In addition, both new phacoemulsification platforms and newly developed devices have been shown to improve efficiency. As a result, we recommend that the integration of these recent developments should be considered in future investigations.     

【In Press】 Changes in intrinsic excitability of ganglion cells in degenerated retinas of RCS rats

AIM: To evaluate the intrinsic excitability of retinal ganglion cells (RGCs) in degenerated retinas. METHODS: We investigated the intrinsic excitability of various morphologically defined RGC types using a combination of patch-clamp recording and the Lucifer yellow tracer in retinal whole-mount preparations harvested from Royal College of Surgeons (RCS) rats, a common retinitis pigmentosa (RP) model, in a relatively late stage of retinal degeneration (P90). Several parameters of RGC morphologies and action potentials (APs) were measured and compared to those of non-dystrophic control rats, including dendritic stratification, dendritic field diameter, peak amplitude, half width, resting membrane potential, AP threshold, depolarization to threshold, and firing rates. RESULTS: Compared with non-dystrophic control RGCs, more depolarizations were required to reach the AP threshold in RCS RGCs with low spontaneous spike rates and in RCS OFF cells (especially A2o cells), and RCS RGCs maintained their dendritic morphologies, resting membrane potentials and capabilities to generate APs. CONCLUSION: RGCs are relatively well preserved morphologically and functionally, and some cells are more susceptible to decreased excitability during retinal degeneration. These findings provide valuable considerations for optimizing RP therapeutic strategies.     

Role of intravitreal bevacizumab in the management of Eales’ disease

Purpose To evaluate the role of intravitreal bevacizumab in the treatment of Eales’ disease. Study design Retrospective, interventional case series. Methods Two patients with proliferative Eales’ disease were managed with an intravitreal injection of bevacizumab (1.25 mg). The presence of persistent retinal neovascularization despite adequate laser photocoagulation caused recurrent episodes of vitreous hemorrhage in the first patient. The second patient had florid retinal and disc neovascularization with a dispersed vitreous bleed, which prevented laser therapy. Both patients were followed up for 6 months. Results Rapid regression of the retinal neovascularization and clearing of the vitreous hemorrhage were observed in both cases following intravitreal bevacizumab therapy, allowing laser photocoagulation. In both patients, the visual acuity improved, and no signs of recurrence were observed 6 months post-treatment. Conclusion Intravitreal bevacizumab injections may be effective as an adjunctive or alternative treatment of retinal neovascularization in Eales’ disease, where inadequate visualization precludes laser photocoagulation. This approach may also be useful in avoiding vitreoretinal surgical intervention in certain cases. Intravitreal bevacizumab was well tolerated by our patients, and no adverse effects were observed.     

Establishment of Retinoblastoma Model in NOD-SCID Mice and Study of Metastasis

Purpose: To establish model of retinoblastoma subcutaneously in NOD-SCID mice and study rules of formation and distribution of retinoblastoma metastasis. Methods: Retinoblastoma cells SO-RB50 were inoculated subcutaneously in NOD-SCID mice. Animal acts and tumor formation, growth and metastasis in NOD-SCID mice were observed. Primary and metastatic tumors were studied pathohistologically by HE and immunohistochemical staining. Results: The latent periods of tumor growth were 12-19 days and the taken rate of tumor was 100%. 32 days later, 5 NOD-SCID mice were found with tumors that had metasta sized to areas mainly located in the abdominal cavity and the side of the kidney; the metastatic time of tumors in the mice also differed. The tumor cells of the primary nodules and the metastasis were similar with human retinoblastoma cells and positive in immunohistochemical staining of NSE. Conclusion: The subcutaneous model of retinoblastoma in NOD-SCID mice showed a high taken rate and a short latent period of tumor, which had a high metastatic rate and was the best model in research of behaviors of retinoblastoma at present. Eye Science 2005 ;21:185-191.     

Analysis of Oscillatory Potentials of Flash Electroretinogram in Frequency Domain and Time Domain in Retinal Vein Occlusion

Purpose: To analyse the parameters of frequency domain and time domain of the OPs in branch retinal vein occlusion (BRVO) and central retinal vein occlusion (CRVO). Methods : OPs from 9 eyes of BRVO, 9 eyes of CRVO and 40 normal control eyes were tested . The frequency spectra of the OPs were derived through Fast Fourier Transform (FFT) . The mean frequency spectra, the total power, the maximum magnitude, the maximum power and the dominant frequency in frequency domain of the OPs from the eyes of BRVO, CRVO and the normal control group were compared with each other. The OPs waveforms were reconstructed with the OPs frequency spectra data by counter-FFT. In time domain, the latencies, the amplitudes and the sum of the amplitudes of the four wavelets of OPs were measured and compared in the above subjects.Results: There were no statistically significant differences in the magnitudes of frequency spectra, the total power, the maximum magnitude and the maximum power in the frequency range from 110 to 250 Hz     

Surgical reversal of Presbyopia starts in China

Ｄｒ.Ｓｈａｃｈａｒ ,ｉｎ 1992 ,ｐｕｔｆｏｒｗａｒｄａｃｈａｌｌｅｎｇｅｔｏｔｈｅＨｅｌｍｈｏｌｔｚ’ｓｃｌａｓｓｉｃａｌｔｈｅｏｒｙｏｆａｃｃｏｍｍｏｄａｔｉｏｎ ,ｗｈｉｃｈｐｒｅｓｂｙ ｏｐｉａｉｓｄｅｄｕｃｅｄｔｈｒｏｕｇｈｔｈｅｄｅｃｒｅａｓｅｄｓ     

Role of interleukin-1β in hypoxia-induced depression of glutamate uptake in retinal Müller cells

Background

It is suggested that hypoxic–ischemic retinal diseases induce loss of retinal ganglion cells. Excess glutamate release is involved in these conditions. A predominant function of Müller cells is to regulate glutamate levels, but in these diseases the function is compromised. The present study was performed to investigate the role of interleukin-1β(IL-1β)on the glutamate uptake in retinal Müller cells under hypoxia and to study the possible mechanism.

Methods

The levels of IL-1β,Kir4.1, and GLAST in retinal Müller cells under hypoxia were analyzed by Western blotting and realtime-RT-PCR, and glutamate uptake assay was undertaken to investigate the activity of GLAST. After being treated with IL-1βunder normoxia, these proteins (Kir4.1 and GLAST) and their mRNAs, and glutamate uptake activity in Müller cells were investigated. To confirm the effect of IL-1βon glutamate uptake activity in Müller cells, addition of IL-1ra was used.

Results

Under hypoxia, Müller cells glutamate uptake, Kir4.1 and GLAST expressions were decreased significantly; however, IL-1βexpression was increased. IL-1βtreatment induced depression of glutamate uptake, decrease of Kir4.1 and GLAST expressions in retinal Müller cells under normoxia. Moreover, addition of IL-1ra significantly ameliorated decreases in Kir4.1 and GLAST expressions, and compromise of glutamate uptake activity in retinal Müller cells under hypoxia.

Conclusions

These findings indicated that decreases in Kir4.1 and GLAST expressions and depression of glutamate uptake in retinal Müller cells under hypoxia may be induced by the inflammatory cytokine IL-1β.     

Rapid Diagnosis of Chlamydial Conjunctivitis in Laboratory

Purpose: To evaluate the techniques of rapid and accurate diagnosis of chlamydialconjunctivitis.Methods: Total 100 conjunctivitis patients (200 eyes) were studied. Twenty-two of100 cases were diagnosed as chlamydial conjunctivitis. The infected epithelia werescraped from tarsal conjunctiva of both eyes and stained separately with Giemsa (100cases) and immunofluorescence (anti-chlamydial antigen monoclonal antibody, 100cases).Result: In immunofluorescent staining, 38 cases were seen positive staining and 62were negative. In Giemsa staining, 29 were positive, and 71 were negative. In 22 caseswith clinical diagnosis of chlamydial conjunctivitis, 13 cases were confirmed, and 9were excluded by immunofluorescent staining. Technically, immunofluorescent andGiemsa stain takes 45 and 40 minutes, respectively.Conclusion: Comparing to Giemsa stain, 38 of 100 scraping specimens were positive(38% ) by immunofluorescent staining, 29 of 100 per cent were positive by Giemsastaining. Giemsa staining takes 5 minutes less     

Corneal Topography Research of Myopia in Chinese

Purpose: To determine corneal topography parameters of myopia in Chinese and help for studies of causes of myopia, distingiush other corneal diseases (such as early keratoconus), further explore the accurateness and safeness of the clinical effects of radii keratotomy(RK) or photorefractive keratectomy (PRK). Methods: Fifty-eight eyes with mild or moderate myopia were examined by computer-assisted photokeratography. (TMS-1 Computed Anatomy Inc. New York. NY)Results: The corneal topography of most (68%) of the examined eyes showed symmetric bowtie pattern; the corneal surface of most (75%) of the examined eyes showed positive aspheric shape (steeper centrally, flatter peripherally); the refractive power of central cornea is at mean 44. 165 ± 1. 429D; the refractive difference between 1 to 25 ring in keratoscpe was at mean 1. 655 ± 0. 785D; the mean SRI was 0. 558 ± 0. 768, the mean SAI was 0. 296 ± 0. 149; the mean Smik was 44. 209±1. 515D. The apex and visual axis were dislocation in all the cornea     

Development of PVEP in Infants and Children

The development of components of VEP was studied in 150 infants and children between 2 weeks and 9 years of age participated as subjects. Ten adult subjects, 25 ito 35 years of age were also studied. The results indicated that the VEP had a simple wave form, consisting of only a slowly rising positive wave to 140‘, 70‘ and 35‘ checks from infants of 2 to 8 weeks following birth. P_1 wave appeared in response to 17.5‘ check stimulus at 10 weeks following birth. The latencies of P_1 components shortened d...     

Morphometry of Axons in Optic Nerves of Siamese‘s Twins

Purpose: To observe the development of optic nerve, we examined four optic nerves from Siameses Twins by absolute counts of axons.Methods: Mean axon diameter, mean axon density, totally axonal population and optic nerve area were noted for each optic nerve. The mean axon diameter and the mean axon density were compared between paraxial(inner sectors) and cortical(outer sectors) areas of the nerves.Results: More myelinated axons were seen in the inner sectors as compared to the outer sectors (average 11 axons/1 000 jjum2 in inner sectors and 34 axons/1 000 u,m2 in outer sectors( P = 0. 036) . The myelinated fibers were also smaller(63 microns) in the outer sectors as compared to the inner sectors(72 microns) ( P - 0. 001). The average cross sectors area for the four 40 week stage optical nerves of Siamese Twins was 3. 32 x 103 as compared to 1 million axons for 32-week-old normals.Conclusion: Our finding of fewer axonal number and small myelinated fibers in the Siamese Twins suggests hypoplasia. Myelinat