Painful-blind eye: A forgotten palliative care.

Painful-blind eye (PBE) is a challenging and debilitating condition that greatly affects the quality of life of patients. Although PBE can result from a variety of etiologies, currently there is no guideline or consensus on how to approach therapeutically these patients, and most treatments are experience-based. We summarized the evidence from available studies to investigate the current state of PBE treatment strategies. This review revealed that the information available about therapeutic approaches in patients with PBE is insufficient and outdated, therefore, new experimental and larger studies are needed to reach an agreement about this condition.

Neuroprotective effect of mesenchymal stem cell-derived extracellular vesicles on optic nerve injury in chronic ocular hypertension.

Mesenchymal stem cells have neuroprotective effects that limit damage to the retina and photoreceptors, and which may be mediated by extracellular vesicles (or exosomes) released by mesenchymal stem cells. To investigate the neuroprotective effect of extracellular vesicles derived from umbilical cord mesenchymal stem cells on glaucoma, we established rat models of chronic ocular hypertension by injecting conjunctival fibroblasts into the anterior chamber to mimic optic nerve injury caused by glaucoma. One week after injury, extracellular vesicles derived from umbilical cord-derived mesenchymal stem cells were injected into the vitreous cavity. We found that extracellular vesicles derived from mesenchymal stem cells substantially reduced retinal damage, increased the number of retinal ganglion cells, and inhibited the activation of caspase-3. These findings suggest that mesenchymal stem cell-derived extracellular vesicles can help alleviate optic nerve injury caused by chronic ocular hypertension, and this effect is achieved by inhibiting cell apoptosis.

Chronic Glaucoma Induced in Rats by a Single Injection of Fibronectin-Loaded PLGA Microspheres: IOP-Dependent and IOP-Independent Neurodegeneration.

To evaluate a new animal model of chronic glaucoma induced using a single injection of fibronectin-loaded biodegradable PLGA microspheres (Ms) to test prolonged therapies. 30 rats received a single injection of fibronectin-PLGA-Ms suspension (MsF) in the right eye, 10 received non-loaded PLGA-Ms suspension (Control), and 17 were non-injected (Healthy). Follow-up was performed (24 weeks), evaluating intraocular pressure (IOP), optical coherence tomography (OCT), histology and electroretinography. The right eyes underwent a progressive increase in IOP, but only induced cohorts reached hypertensive values. The three cohorts presented a progressive decrease in ganglion cell layer (GCL) thickness, corroborating physiological age-related loss of ganglion cells. Injected cohorts (MsF > Control) presented greater final GCL thickness. Histological exams explain this paradox: the MsF cohort showed lower ganglion cell counts but higher astrogliosis and immune response. A sequential trend of functional damage was recorded using scotopic electroretinography (MsF > Control > Healthy). It seems to be a function-structure correlation: in significant astrogliosis, early functional damage can be detected by electroretinography, and structural damage can be detected by histological exams but not by OCT. Males presented higher IOP and retinal and GCL thicknesses and lower electroretinography. A minimally invasive chronic glaucoma model was induced by a single injection of biodegradable Ms.

Clinical presentation, treatment, and genetic and histopathological analysis of juvenile cataracts and secondary glaucoma in a rhesus macaque (Macaca mulatta).

This report describes the clinical and histological findings, genetic study, and treatment in a 1.3-year-old rhesus macaque with bilateral cataracts and unilateral secondary glaucoma. Intravitreal injection of gentamicin decreased the intraocular pressure from 56 to <2 mm Hg. A putative genetic cause of the cataracts was not identified.

[Congenital ocular melanocytosis]. / L'image du mois. Mélanocytose oculaire congénitale.

Congenital oculodermal melanocytosis represents a unilateral accumulation of melanocytes in the episclera, sclera and uveal tract. Clinically, it manifests with iris heterochromia, episcleral and scleral pigmented patches, dark pigmentation of the trabecular meshwork and the fundus. This congenital disorder is a predisposing factor for uveal melanoma and chronic glaucoma. We report here the case of a Caucasian woman who presents some of these characteristics.

La mélanocytose oculaire congénitale représente une accumulation unilatérale de mélanocytes au niveau de la sclère, l'épisclère et l'uvée. D'un point de vue clinique, on peut retrouver une hétérochromie irienne, une pigmentation de l'épisclère, de la sclère, du trabéculum et du fond d'œil. Un risque majoré de mélanome uvéal et de glaucome chronique est retrouvé chez ces patients. Nous rapportons ici le cas d'une jeune patiente caucasienne qui présente certaines de ces caractéristiques cliniques de façon tout à fait asymptomatique.

Glaucoma-associated pain results in mechanical sensitivity changes in dogs: A pilot study.

PURPOSE: To explore the effects of chronic, uncontrolled glaucoma on pressure sensitivity in dogs before and after enucleation of the painful globe. METHODS: Client-owned dogs undergoing enucleation for chronic glaucoma with no other sources of pain were enrolled. Normal dogs of similar breeds and skull morphology were enrolled as controls. Craniofacial ratio (CFR) and relative palpebral fissure width (RPFW) were assessed in all patients. Serial mechanical quantitative sensory testing (QST) was performed the day before surgery, and 14, 30, 60, and 120 days after surgery. QST consisted of electronic Von Frey (eVF), and blunt algometry (BA) performed above and below the nonglaucomatous eye, the metacarpus, and metatarsus. Cochet-Bonnet esthesiometry (CB) was also performed on the remaining eye. RESULTS: Twelve dogs (6 per group) were included. Compared to baseline values, sensitivity tended to decrease over time (increased thresholds) in treatment dogs while it stayed constant or increased slightly in control dogs. The difference in change from baseline sensitivity between control and treatment groups was significant at day 120 using BA at supraorbital (P = .0153), infraorbital (P = .0209), and metacarpal sites (P = .007) and overall (P = .0470). This divergence was also significant using CB (P = .0470) on the opposite cornea. As patient CFR and RPFWV increased, both eVF (P = .005-.023) and BA (P = .004-.041) increased. CONCLUSIONS: Sensitivity to mechanical stimuli decreased both locally and at remote sites in dogs following enucleation for painful chronic glaucoma. Cranial conformation is associated with differences in sensitivity.

Brimonidine enhances inhibitory postsynaptic activity of OFF- and ON-type retinal ganglion cells in a Wistar rat chronic glaucoma model.

Glaucoma is a multifactorial disease in which retinal ganglion cells (RGCs) undergo excitotoxic damage, leading to their degeneration. The α2-adrenoceptor (α2-AR) agonist brimonidine exerts a neuroprotective effect by regulating postsynaptic excitatory N-methyl-D-aspartate (NMDA) receptor activity in RGCs. However, researchers have not clearly determined whether or how brimonidine regulates inhibitory synaptic transmission in rat models of chronic glaucoma. Whole-cell voltage-clamp and current-clamp recordings were performed in ON- and OFF-type RGCs in retinal slices. Brimonidine directly and acutely enhanced γ-aminobutyric acidergic (GABAergic) transmission mediated by ionotropic GABAA receptors in ON- and OFF-type RGCs in rat retinal slices; this effect occurred at the synaptic terminals and was independent of action potentials and multi-synaptic connections. The highly selective α2-AR antagonist yohimbine blocked the effects of brimonidine. Regarding the postsynaptic GABA receptor sensitivity, brimonidine also increased the amplitude of the GABA-induced current. Additionally, compared to RGCs from the control group, the frequencies and amplitudes of spontaneous excitatory postsynaptic currents (sEPSCs) and miniature excitatory postsynaptic currents (mEPSCs) did not change after brimonidine gravity perfusion. Brimonidine significantly decreased the spontaneous firing frequency of rat RGCs with intact synaptic inputs and decreased the resting membrane potential of RGCs, changes that were blocked by the highly selective GABAA receptor antagonist SR95531. SR95531 alone increased spontaneous action potentials and the resting membrane potential. Based on these findings, an α2-AR agonist facilitated the frequency of the GABAergic inhibitory postsynaptic currents (IPSCs), directly increased the amplitude of the postsynaptic GABA-induced current (GABA receptor reactivity/sensitivity), suppressed the firing frequency of spontaneous action in RGCs with intact synaptic inputs and decreased the resting membrane potential of RGCs, thus deactivating RGCs from the neural network level and reducing the excitotoxic damage occurring during the pathological process of chronic glaucoma.

Diode laser cyclophotocoagulation paves way to a safer trabeculectomy in eyes with medically uncontrollable intraocular pressure.

High intraocular pressure (IOP) not responding to systemic and topical anti-glaucoma medications renders the eye at risk for both intra- and post-operative complications of glaucoma filtration surgery. Laser cyclophotocoagulation is able to lower IOP in such refractory glaucoma eyes and may make the surgical event safer. This study assessed diode laser cyclophotocoagulation (DLCP) when used as a temporary measure for lowering IOP prior to performing trabeculectomy. This study is a  retrospective analysis of cases planned for trabeculectomy surgery, uncontrolled on maximally tolerable systemic anti-glaucoma medications. They were analysed for response to DLCP in terms of IOP control, vision-related complications, increased inflammation, post-trabeculectomy hypotony and chances of phthisis and ciliary shutdown. Twelve eyes of ten patients aged 35-65 years were identified and all followed up for at least 2 years. One week following DLCP, the IOP (mean ± SD) declined by 51 % from 46.8 ± 5.4 to 22.8 ± 3.3 mmHg. The IOP was further reduced to 15.4 ± 2.7 mmHg at 4 weeks after trabeculectomy; it remained in the mid-teens for a minimum of 2 years in all cases. The mean (±SD) visual acuity improved from 1.4 ± 0.4 to 0.8 ± 0.4 LogMAR equivalents following trabeculectomy. In four eyes, phacoemulsification was performed 5-7 months after trabeculectomy with improvement in best-corrected visual acuity. One patient developed transient hypotony, post-trabeculectomy, which resolved by 6 days. There were no other complications like increased inflammation, prolonged hypotony or suprachoroidal haemorrhage. DLCP is, thus, effective and safe for temporarily controlling IOP; thereby trabeculectomy can be performed in a quieter ocular milieu.

Differential Modulation of GABAA and NMDA Receptors by an α7-nicotinic Acetylcholine Receptor Agonist in Chronic Glaucoma.

Presynaptic modulation of γ-aminobutyric acid (GABA) release by an alpha7 nicotinic acetylcholine receptor (α7-nAChR) agonist promotes retinal ganglion cell (RGC) survival and function, as suggested by a previous study on a chronic glaucomatous model from our laboratory. However, the role of excitatory and inhibitory amino acid receptors and their interaction with α7-nAChR in physiological and glaucomatous events remains unknown. In this study, we investigated GABAA and N-methyl-D-aspartate (NMDA) receptor activity in control and glaucomatous retinal slices and the regulation of amino acid receptor expression and function by α7-nAChR. Whole-cell patch-clamp recordings from RGCs revealed that the α7-nAChR specific agonist PNU-282987 enhanced the amplitude of currents elicited by GABA and reduced the amplitude of currents elicited by NMDA. The positive modulation of GABAA receptor and the negative modulation of NMDA receptor (NMDAR) by PNU-282987-evoked were prevented by pre-administration of the α7-nAChR antagonist methyllycaconitine (MLA). The frequency and the amplitude of glutamate receptor-mediated miniature glutamatergic excitatory postsynaptic currents (mEPSCs) were not significantly different between the control and glaucomatous RGCs. Additionally, PNU-282987-treated slices showed no alteration in the frequency or amplitude of mEPSCs relative to control RGCs. Moreover, we showed that expression of the α1 subunit of the GABAA receptor was downregulated and the expression of the NMDAR NR2B subunit was upregulated by intraocular pressure (IOP) elevation, and the changes of high IOP were blocked by PNU-282987. In conclusion, retina GABAA and NMDARs are modulated positively and negatively, respectively, by activation of α7-nAChR in in vivo chronic glaucomatous models.

Over-diagnosis and over-treatment in Ophthalmology: A review of the literature. / Sobrediagnóstico y sobretratamiento en Oftalmología: revisión de la literatura.

OBJECTIVE: To determine if the pernicious effects of over-diagnosis and over-treatment have been studied in the most common ocular diseases. MATERIAL AND METHODS: Bibliographic search conducted in PubMed. RESULTS: The search algorithm used retrieved 29 articles related with the topic. Most of them address the issue tangentially. Only 4 of them address the problem directly. One of them focuses on the problem of over-diagnosis and over-treatment in idiopathic intracranial hypertension. The remaining 3 focus on the problem of over-diagnosis and over-treatment in glaucoma. CONCLUSION: The ophthalmology community has thought very little about the detrimental effects of over-diagnosis and over-treatment.

Glaucoma crónico de ángulo estrecho en gemelas dicigóticas / Chronic narrow-angle glaucoma found in dizygotic twins

Caso clínico: se informa el caso de una pareja de gemelas dicigóticas con diagnóstico de glaucoma crónico de ángulo estrecho en 2004, cuyol padre murió ciego; una hija de una de ellas fue diagnosticada posteriormente como afectada de glaucoma crónico de ángulo abierto. Se determinó la cigosidad de las gemelas mediante protocolo establecido al respecto. En los 4 ojos de las pacientes se determinaron presiones intraoculares por aplanación en cifras que fluctuaban entre 26-32 mmHg, cámaras anteriores y ángulos camerulares estrechos, perimetrías computarizadas tubulares en 3 ojos respetando los 5° centrales y en otro tubular que respetaba los 10° centrales con atrofias ópticas en evolución en los 4 ojos. Se efectuó trabeculectomía bilateral en ambas pacientes y se mantuvo el control de su enfermedad glaucomatosa. Conclusiones: se plantea la necesidad de la búsqueda de otros afectados en un núcleo familiar donde se diagnostiquen pacientes con glaucoma crónico de ángulo estrecho

Clinical case: here is the case of a dizygotic twin pair diagnosed with chronic narrow-angle glaucoma in 2994. Their father had died blind and a daughter of one of them was later diagnosed as a chronic open-angle glaucoma patient. A specific protocol allowed determining the zygocity of the twins. The intraocular pressures in the four eyes of the patients were measured with applanation tonometry and ranged 26-32 mmHg, narrow anterior chambers and camerular angles, computerized tubular perimetries in three eyes around central 5° and another tubular perimetry of central 10°, with developing atrophies in the four eyes. Both patients underwent bilateral trabeculectomy and the control over their glaucoma disease was kept. Conclusions: It is necessary to look for other people affected in a family setting where there exists diagnosis of chronic narrow-angle glaucoma

An algorithm for glaucoma screening in clinical settings and its preliminary performance profile.

PURPOSE: To devise and evaluate a screening algorithm for glaucoma in clinical settings. METHODS: Screening included examination of the optic disc for vertical cupping (≥0.4) and asymmetry (≥0.15), Goldmann applanation tonometry (≥21 mmHg, adjusted or unadjusted for central corneal thickness), and automated perimetry. In the diagnostic step, retinal nerve fiber layer imaging was performed using scanning laser polarimetry. Performance of the screening protocol was assessed in an eye hospital-based program in which 124 non-physician personnel aged 40 years or above were examined. A single ophthalmologist carried out the examinations and in equivocal cases, a glaucoma subspecialist's opinion was sought. RESULTS: Glaucoma was diagnosed in six cases (prevalence 4.8%; 95% confidence interval, 0.01-0.09) of whom five were new. The likelihood of making a definite diagnosis of glaucoma for those who were screened positively was 8.5 times higher than the estimated baseline risk for the reference population; the positive predictive value of the screening protocol was 30%. Screening excluded 80% of the initial population. CONCLUSION: Application of a formal screening protocol (such as our algorithm or its equivalent) in clinical settings can be helpful in detecting new cases of glaucoma. Preliminary performance assessment of the algorithm showed its applicability and effectiveness in detecting glaucoma among subjects without any visual complaint.

Economic burden of glaucoma in Rivers State, Nigeria.

BACKGROUND: Primary open angle glaucoma is reported to blind 150,000 people in the Nigerian population and over 7000 in Rivers State, and requires constant follow-up. Compliance is a challenge, given that most inhabitants live below the poverty line. This study was performed to determine how Nigerian patients are affected economically by the disease. METHODS: Consecutive adult patients attending the eye clinic of the University of Port Harcourt Teaching Hospital, Rivers State, Nigeria, with a diagnosis of primary open angle glaucoma and on outpatient antiglaucoma treatment in the first 6 months of 2006, were recruited for the study. The lowest paid government worker was on USD50 (N7500.00) per month and the gross domestic product per capita was USD1150 for the period under review. RESULTS: We enrolled 120 consecutive patients of mean age 52.7 ± 10.4 years, with a male to female ratio of 2:3. The most common occupations were in the civil service (n = 56, 46.7%). All participants were on topical antiglaucoma treatment. The average cost of medical antiglaucoma medication was N6000 (USD40) per month. Computed to include indirect costs, including medical laboratory tests, transportation, and care by patient escorts, an average sum of USD105.4 (N15,810) was spent by each patient per month. Most of the patients (73.3%) were responsible for their own treatment costs. No patient accepted the cheaper option of surgery (USD275.4, N41,310). Eighty of the patients (66.7%) visited our eye clinic monthly. Direct and indirect loss to the economy was USD3,064587 per annum from those already blind. This was in addition to the USD 4.1 million being spent yearly on medical treatment by those who were visually impaired by glaucoma. CONCLUSION: Middle-income earners spent over 50% of their monthly income and low-income earners spend all their monthly earnings on treatment for glaucoma. This situation often resulted in noncompliance with treatment and hospital follow-up visits. To reduce the economic burden of glaucoma, trabeculectomy performed by experienced surgeons should be offered as first-line treatment for glaucoma in this country, rather than medical therapy.

Caracterización del glaucoma crónico simple en un área de salud del Municipio Especial Isla de la Juventud / Characterization of simple chronic glaucoma in a health area from the Isla de la Juventud Special Municipality

Objetivo: identificar las características clínico-epidemiológicas del glaucoma crónico simple en personas mayores de 40 años, en el área de salud Dr. Juan Manuel Páez Inchausti, Nueva Gerona, Isla de la Juventud. Métodos: se realizó un estudio descriptivo y transversal durante el segundo semestre de 2008, en una de las dos áreas de salud que cubren la atención primaria de la población de Nueva Gerona. Se chequeó el 98,8 por ciento de la población mayor de 15 años y, después de aplicados los criterios de selección, fueron considerados 90 pacientes con diagnóstico previo de la enfermedad, de acuerdo con los parámetros estipulados para el seguimiento de esta. Se analizaron las variables edad, sexo, color de la piel, relación presión intraocular-excavación papilar, alteraciones campimétricas, síntomas y signos, antecedentes familiares de la enfermedad según grado de parentesco y enfermedades sistémicas y oculares asociadas con enfoque de riesgo. El procesamiento de la información se realizó mediante el método porcentual. Resultados: se reportó mayor número de pacientes entre 60 y 69 años (24,4 por ciento), de mujeres (53,3 por ciento) y de piel blanca (38,9 por ciento). Los rangos predominantes de valores de presión intraocular y de excavación papilar fueron entre 16 y 21 mmHg (40,0 por ciento), y entre 0,4 y 0,7 (37,8 por ciento); en la relación entre ambas variables predominaron ambos rangos (16,7 por ciento). Conclusiones: Las características clínico-epidemiológicas más relevantes del glaucoma crónico simple en los pacientes estudiados no difieren, en general, de lo reportado en la literatura, con excepción del predominio en mujeres de piel blanca, lo que puede deberse a la conformación de la muestra. La información obtenida del presente estudio debe considerarse parte del registro inicial de las características de la enfermedad en Cuba(AU)

Objective: To identify the clinical-epidemiological features of simple chronic glaucoma in persons aged over 40 in the "Dr. Juan Manuel Pßez Inchausti" health area, Nueva Gerona, Isla de la Juventud municipality. Methods: A cross-sectional study was conducted during the second trimester of 2008 in one the health area covering the primary care of inhabitants of Nueva Gerona. The 98.8 percent of patients aged over 15 was examined and after applications of selection criteria, 90 patients with a diagnosis previous to disease were considered according to the stipulated parameters for its follow-up. Following variables were analyzed: age, sex, skin color, relation intraocular-papillary excavation, campimetry alterations, symptoms and signs, family disease backgrounds according to the relationship degree and systemic and ocular diseases associated with risk approach. The information processing was made by conceptual method. Results: There was more reported patients aged between 60 and 69 (24.4 percent), of women (53.3 percent) and of white race (38.9 percent). The predominant values ranks of intraocular pressure and of papillary excavation were between 16 and 21 mmHg (40.0 percent), between 0.4 and 0.7 (37.8 percent); in relation between both variables the two ranks predominate (16.7 percent). Conclusions: The more relevant clinical-epidemiological features of the simple chronic glaucoma in study patients not differing in general from that reported in literature, except the white race women predominance maybe due to sample conformation. The information obtained from present study must to be considered as part of initial registry of disease features in Cuba(AU)

Caracterización del glaucoma crónico simple en un área de salud del Municipio Especial Isla de la Juventud / Characterization of simple chronic glaucoma in a health area from the Isla de la Juventud Special Municipality

Objetivo: identificar las características clínico-epidemiológicas del glaucoma crónico simple en personas mayores de 40 años, en el área de salud Dr. Juan Manuel Páez Inchausti, Nueva Gerona, Isla de la Juventud. Métodos: se realizó un estudio descriptivo y transversal durante el segundo semestre de 2008, en una de las dos áreas de salud que cubren la atención primaria de la población de Nueva Gerona. Se chequeó el 98,8 por ciento de la población mayor de 15 años y, después de aplicados los criterios de selección, fueron considerados 90 pacientes con diagnóstico previo de la enfermedad, de acuerdo con los parámetros estipulados para el seguimiento de esta. Se analizaron las variables edad, sexo, color de la piel, relación presión intraocular-excavación papilar, alteraciones campimétricas, síntomas y signos, antecedentes familiares de la enfermedad según grado de parentesco y enfermedades sistémicas y oculares asociadas con enfoque de riesgo. El procesamiento de la información se realizó mediante el método porcentual. Resultados: se reportó mayor número de pacientes entre 60 y 69 años (24,4 por ciento), de mujeres (53,3 por ciento) y de piel blanca (38,9 por ciento). Los rangos predominantes de valores de presión intraocular y de excavación papilar fueron entre 16 y 21 mmHg (40,0 por ciento), y entre 0,4 y 0,7 (37,8 por ciento); en la relación entre ambas variables predominaron ambos rangos (16,7 por ciento). Conclusiones: Las características clínico-epidemiológicas más relevantes del glaucoma crónico simple en los pacientes estudiados no difieren, en general, de lo reportado en la literatura, con excepción del predominio en mujeres de piel blanca, lo que puede deberse a la conformación de la muestra. La información obtenida del presente estudio debe considerarse parte del registro inicial de las características de la enfermedad en Cuba

Objective: To identify the clinical-epidemiological features of simple chronic glaucoma in persons aged over 40 in the "Dr. Juan Manuel Pßez Inchausti" health area, Nueva Gerona, Isla de la Juventud municipality. Methods: A cross-sectional study was conducted during the second trimester of 2008 in one the health area covering the primary care of inhabitants of Nueva Gerona. The 98.8 percent of patients aged over 15 was examined and after applications of selection criteria, 90 patients with a diagnosis previous to disease were considered according to the stipulated parameters for its follow-up. Following variables were analyzed: age, sex, skin color, relation intraocular-papillary excavation, campimetry alterations, symptoms and signs, family disease backgrounds according to the relationship degree and systemic and ocular diseases associated with risk approach. The information processing was made by conceptual method. Results: There was more reported patients aged between 60 and 69 (24.4 percent), of women (53.3 percent) and of white race (38.9 percent). The predominant values ranks of intraocular pressure and of papillary excavation were between 16 and 21 mmHg (40.0 percent), between 0.4 and 0.7 (37.8 percent); in relation between both variables the two ranks predominate (16.7 percent). Conclusions: The more relevant clinical-epidemiological features of the simple chronic glaucoma in study patients not differing in general from that reported in literature, except the white race women predominance maybe due to sample conformation. The information obtained from present study must to be considered as part of initial registry of disease features in Cuba

Individualización de pacientes con baja visión en el Centro Oftalmológico del Hospital General Docente Dr Juan Bruno Zayas Alfonso / Individualization of low vision patients in Dr Juan Bruno Zayas Alfonso Teaching General Hospital Ophthalmologic Center

Se efectuó un estudio descriptivo y transversal de 73 pacientes con baja visión, que asistieron a la consulta del Centro Oftalmológico del Hospital General Docente Dr Juan Bruno Zayas Alfonso de Santiago de Cuba, desde julio hasta diciembre del 2009, a fin de describir algunas características clínicas y demográficas. La degeneración macular asociada a la edad primó en más de 25,0 por ciento de los integrantes de la casuística, seguida por el glaucoma crónico simple y la miopía degenerativa y, según lugar de procedencia, los pertenecientes al municipio de Santiago de Cuba representaron 73,0 por ciento del total. Se logró rehabilitar a 89,0 por cientode los pacientes examinados y tratados

A descriptive and cross sectional study of 73 patients with low vision who visited the Ophthalmologic Center at Dr Juan Bruno Zayas Alfonso Teaching General Hospital in Santiago de Cuba was carried out from July to December 2009 in order to describe some clinical and demographic characteristics. Macular degeneration associated with age prevailed in more than the 25,0 per cent of the case material, followed by simple chronic glaucoma and degenerative myopia and, according to origin place, those belonging to Santiago de Cuba municipality represented 73,0 per cent of the total. It was possible to rehabilitate the 89,0 per cent of the examined and treated patients

Expression of Nitric Oxide Synthase Isoforms in a Rat Model of Chronic Glaucoma

PURPOSE: This study investigated the expression of three isoforms of nitric oxide synthase (NOS): neuronal (nNOS), inducible (iNOS), and endothelial (eNOS) in an experimental rat model of chronic glaucoma. The aim was to research the role of nitric oxide (NO) as a neurotoxic molecule in connection with damage to and the degeneration of retinal ganglion cells in glaucoma. METHODS: Retinal tissues were obtained after inducing chronic elevation of intraocular pressure by cauterization of episcleral vessels. We then performed quantification and localization of NOS isoforms through western blot and immuno-fluorescence staining of the tissues. RESULTS: The expression of nNOS and iNOS increased significantly but that of eNOS did not. nNOS expressed in the amacrine and displaced amacrine cell of the normal retinal tissue, as well as in retinal ganglion cells in the experimental group. iNOS that expressed in the microglia of the normal retinal tissue was also expressed in the cell thought to be an astrocyte or Muller cell end-feet in the experimental group. Administration of L-NAME (NG-nitro-L-arginine-methyl-esther), a non-specific NOS inhibitor, tended to reduce retinal ganglion cell loss, but this result was without statistical significance. CONCLUSIONS: These results showed that the cytotoxicity of excessive NO took part in retinal ganglion cell loss in glaucoma, and the expression of nNOS in retinal ganglion cells suggests that it may play an important role in the selective death of the retinal ganglion cell.

EFFECTS OF TETRAMETHYLPYRAZINE ON RETINA OF RABBITS WITHEXPERIMENTAL GLAUCOMA / 药物分析学报

Objective To observe the effects of tetramethyipyrazine(TMP) on retina to find out whether it can protect retina from glaucomatous damage. Methods Twenty-four rabbits were randomly divided into four groups. One eye of each rabbit was model eye induced by 2％ methylcellulous, and the other was control eye. Normal saline, TMP, timolol and a combination of timolol and TMP were administrated to group A, B, C and D respectively. At the end of 4th week, eyes were excavated for light and electron microscopic study. Results The numbers of ganglion cells (P ＜0. 01) and bipolar cells (P ＜0. 01) in model eye were different significantly between group A and B. In group A, the model eye ganglion cells were karyopyknosis, chromatin margination and nuclear membrane rupture; some in ner nuclear cells dcveloped marked lytic changes; outer segment appeared disorganized; but group B changed slight ly. Conclusion The results suggest that TMP may protect retina from glaucomatous damage.