Exploring the Potential of Wild Olive (Acebuche) Oil as a Pharm-Food to Prevent Ocular Hypertension and Fibrotic Events in the Retina of Hypertensive Mice.

SCOPE: Our laboratory has previously described the antioxidant and anti-inflammatory potential of a wild olive (acebuche, ACE) oil against hypertension-associated vascular retinopathies. The current study aims to analyze the antifibrotic effect of ACE oil on the retina of hypertensive mice. METHODS AND RESULTS: Mice are rendered hypertensive by administration of NG-nitro-L-arginine-methyl-ester (L-NAME) and simultaneously subjected to dietary supplementation with ACE oil or a reference extra virgin olive oil (EVOO). Intraocular pressure (IOP) is measured by rebound tonometry, and retinal vasculature/layers are analyzed by fundus fluorescein angiography and optical coherence tomography. Different fibrosis-related parameters are analyzed in the retina and choroid of normotensive and hypertensive mice with or without oil supplementation. Besides preventing the alterations found in hypertensive animals, including increased IOP, reduced fluorescein signal, and altered retinal layer thickness, the ACE oil-enriched diet improves collagen metabolism by regulating the expression of major fibrotic process modulators (matrix metalloproteinases, tissue inhibitors of metalloproteinases, connective tissue growth factor, and transforming growth factor beta family). CONCLUSION: Regular consumption of EVOO and ACE oil (with better outcomes in the latter) might help reduce abnormally high IOP values in the context of hypertension-related retinal damage, with significant reduction in the surrounding fibrotic process.

Protection of retinal ganglion cells and retinal vasculature by Lycium barbarum polysaccharides in a mouse model of acute ocular hypertension.

Acute ocular hypertension (AOH) is a condition found in acute glaucoma. The purpose of this study is to investigate the protective effect of Lycium barbarum polysaccharides (LBP) and its protective mechanisms in the AOH insult. LBP has been shown to exhibit neuroprotective effect in the chronic ocular hypertension (COH) experiments. AOH mouse model was induced in unilateral eye for one hour by introducing 90 mmHg ocular pressure. The animal was fed with LBP solution (1 mg/kg) or vehicle daily from 7 days before the AOH insult till sacrifice at either day 4 or day 7 post insult. The neuroprotective effects of LBP on retinal ganglion cells (RGCs) and blood-retinal-barrier (BRB) were evaluated. In control AOH retina, loss of RGCs, thinning of IRL thickness, increased IgG leakage, broken tight junctions, and decreased density of retinal blood vessels were observed. However, in LBP-treated AOH retina, there was less loss of RGCs with thinning of IRL thickness, IgG leakage, more continued structure of tight junctions associated with higher level of occludin protein and the recovery of the blood vessel density when compared with vehicle-treated AOH retina. Moreover, we found that LBP provides neuroprotection by down-regulating RAGE, ET-1, Aß and AGE in the retina, as well as their related signaling pathways, which was related to inhibiting vascular damages and the neuronal degeneration in AOH insults. The present study suggests that LBP could prevent damage to RGCs from AOH-induced ischemic injury; furthermore, through its effects on blood vessel protection, LBP would also be a potential treatment for vascular-related retinopathy.

Effect of the Honan intraocular pressure reducer on intraocular pressure increase following intravitreal injection using the tunneled scleral technique.

OBJECTIVE: To determine the effect of the Honan intraocular pressure reducer (HIPR) on the rise in intraocular pressure (IOP) after an intravitreal injection using a tunneled scleral incision. DESIGN: This was a prospective, comparative, controlled, non-randomized clinical study. METHODS: Sixty eyes of 60 patients who received intravitreal injections with the tunneled scleral technique were allocated into two groups, one with and one without application of the HIPR. The pre-operative IOP both before and after application of the HIPR, and the IOP immediately postoperative, and at 3 and 10 min postoperatively were evaluated. The vitreous reflux was estimated by measuring the large diameter of the sub-conjunctival bleb formed after intravitreal injection. RESULTS: The pre-operative IOP in the HIPR group was significantly lower than that in the non-HIPR group following application of the HIPR. The immediate postoperative IOP was significantly lower in the HIPR group than in the non-HIPR group. The IOP at 10 min postoperatively was lower in the HIPR group than in the non-HIPR group. There was no difference in the amount of vitreous reflux between the HIPR and the non-HIPR groups. CONCLUSION: The use of the HIPR reduces the IOP after an intravitreal injection using the tunneled scleral technique. However, the HIPR does not appear to affect a reduction in the vitreous reflux.

Adjunctive bevacizumab in patients undergoing Ahmed valve implantation: a pilot study.

BACKGROUND AND OBJECTIVE: To report on preliminary findings of adjunctive subconjunctival bevacizumab (SCB) injections in patients undergoing Ahmed valve implantation (AVI) (New World Medical, Rancho Cucamonga, CA). PATIENTS AND METHODS: The study was approved by the institution's ethics committee. Patients were prospectively recruited during a 1-month period and randomized to receive AVI with postoperative SCB (days 1 and 7, n = 7) or AVI without SCB (n = 6). RESULTS: Baseline intraocular pressure (IOP) in the treatment (AVI+SCB) group was 19.4 ± 8.6 mm Hg, whereas baseline IOP in the control (AVI) group was 32.1 ± 17.7 mm Hg (P = .119). Final IOP was 13.8 mm Hg (n = 7) for the treatment group and 12.7 mm Hg for the control group (n = 5, P = .790). One eye in the control group required further glaucoma intervention at day 45 and was considered a failure. The pre-massage postoperative IOP was significantly lower for the treatment group only at day 45 (16.1 vs 26.0 mm Hg, P = .012). Mean post-massage IOP was significantly lower in the treatment group at day 15 (11.28 vs 17.16 mm Hg, P = .004), day 30 (11.28 vs 20.83 mm Hg, P = .015), and day 45 (12.16 vs 21.33 mm Hg, P = .001), and similar at month 3. Mean change in bleb area was 11.4 mm(2) in the treatment group and -0.4 mm(2) in the control group (P = .036 and P = .361, respectively, Student's paired samples t test). CONCLUSION: Bevacizumab was associated with a less aggressive hypertensive period as measured by post-massage IOP measurements, postoperative glaucoma medications, and cross-sectional bleb area by ultrasound. Further prospective studies are needed to better understand the utility of SCB at the time of AVI surgery.

Use of an adult rat retinal explant model for screening of potential retinal ganglion cell neuroprotective therapies.

PURPOSE. To validate an established adult organotypic retinal explant culture system for use as an efficient medium-throughput screening tool to investigate novel retinal ganglion cell (RGC) neuroprotective therapies. METHODS. Optimal culture conditions for detecting RGC neuroprotection in rat retinal explants were identified. Retinal explants were treated with various recognized, or purported, neuroprotective agents and cultured for either 4 or 7 days ex vivo. The number of cells surviving in the RGC layer (RGCL) was quantified using histologic and immunohistochemical techniques, and statistical analyses were applied to detect neuroprotective effects. RESULTS. The ability to replicate previously reported in vivo RGC neuroprotection in retinal explants was verified by demonstrating that caspase inhibition, brain-derived neurotrophic factor treatment, and stem cell transplantation all reduced RGCL cell loss in this model. Further screening of potential neuroprotective pharmacologic agents demonstrated that betaxolol, losartan, tafluprost, and simvastatin all alleviated RGCL cell loss in retinal explants, supporting previous reports. However, treatment with brimonidine did not protect RGCL neurons from death in retinal explant cultures. Explants cultured for 4 days ex vivo proved most sensitive for detecting neuroprotection. CONCLUSIONS. The current adult rat retinal explant culture model offers advantages over other models for screening potential neuroprotective drugs, including maintenance of neurons in situ, control of environmental conditions, and dissociation from other factors such as intraocular pressure. Verification that neuroprotection by previously identified RGC-protective therapies could be replicated in adult retinal explant cultures suggests that this model could be used for efficient medium-throughput screening of novel neuroprotective therapies for retinal neurodegenerative disease.

Retinal oxidative stress induced by intraocular hypertension in rats may be ameliorated by brimonidine treatment and N-acetyl cysteine supplementation.

PURPOSE: To investigate the effect of brimonidine and N-acetyl cysteine (NAC) on retinal oxidative status under ocular hypertension. MATERIALS AND METHODS: Ocular hypertension is produced in right eyes of 60 rats through intraocular injection of sodium hyaluronate. The left eyes received intracameral saline as sham. Twenty right eyes (brimonidine group) received topical brimonidine twice a day for a week. Other 20 eyes received intraperitoneal NAC (NAC group) once a day. Another group of 20 eyes were followed without any drugs but only intracameral sodium hyaluronate (sodium hyaluronate group) into right eyes. RESULTS: Intraocular injection of sodium hyaluronate increased intraocular pressure for a week and caused retinal peroxidation and decreased glutathione peroxidase and catalase levels. Brimonidine and NAC treatment reversed the retinal oxidative stress created by high intraocular pressure. CONCLUSIONS: Brimonidine and NAC supplementation provide antioxidative properties to retina and decrease retinal damage induced by ocular hypertension.

A dietary combination of omega-3 and omega-6 polyunsaturated fatty acids is more efficient than single supplementations in the prevention of retinal damage induced by elevation of intraocular pressure in rats.

BACKGROUND: To evaluate the effect of a dietary combination of omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) compared to single PUFA supplementations on the outcome of a substantial elevation of intraocular pressure (IOP) in rats. METHODS: Sprague Dawley rats were fed for 6 months with either a control diet, a diet enriched with omega-3 PUFAs (eicosapentaenoic acid, EPA, and docosahexaenoic acid, DHA), a diet enriched with omega-6 PUFAs (gamma-linolenic acid, GLA) or a diet enriched with both omega-3 and omega-6 PUFAs (EPA + DHA and GLA). After 3 months of feeding, elevation of IOP was induced by photocoagulation of the episcleral veins, limbus and trabecular meshwork using a 532-nm laser. IOP and scotopic electroretinograms (ERGs) were monitored after the induction of IOP elevation until the end of the nutritional supplementation. Retinal morphometry and GFAP immunohistochemistry were performed 3 months after laser photocoagulation. Retinal ganglion cells (RGCs) were quantified using retrograde labelling. RESULTS: A significant rise in IOP was observed in the laser-treated eyes. PUFA supplementation did not influence the time course of IOP in the laser-treated eyes. Three months after laser photocoagulation, the activation of glial cells observed in the laser-treated eyes was significantly lower in animals fed with the EPA + DHA + GLA diet when compared to those fed the control diet, while single supplementations with either EPA + DHA or GLA were not effective. The same protective effect of the EPA + DHA + GLA combination was observed on retinal structures in the laser-treated eyes. However, PUFA supplementation did not influence either ERG b-wave amplitude or the RGC loss in the laser-treated eyes. CONCLUSIONS: This study demonstrates that a 6-month supplementation with a combination of omega-3 and omega-6 PUFAs is more effective than single supplementations, since the EPA + DHA + GLA dietary combination prevented retinal cell structure and decreased glial cell activation induced by the elevation of IOP in rats.

Effect of topical Ginkgo biloba extract on steroid-induced changes in the trabecular meshwork and intraocular pressure.

OBJECTIVE: To study the effects of Ginkgo biloba extract (GBE) on dexamethasone (DEX)-induced ocular hypertension. METHODS: Rabbits aged 7 weeks received topical TobraDEX (Alcon Labs, Hünenberg, Switzerland) and/or 5 microg of GBE four times daily for 14 days. Intraocular pressure (IOP) was recorded every 3 days. After enucleation, trabecular meshwork (TM) cellularity and extracellular matrix deposition were graded. The effect of GBE on apoptosis and expression of myocilin and cell stress-related genes in DEX-treated human TM cells were studied by immunofluorescence, Western blotting, and quantitative polymerase chain reaction. RESULTS: Ginkgo biloba extract suppressed DEX-induced IOP elevation in rabbits. It reduced the DEX-associated accumulation of extracellular materials within the cribriform layers of the TM and achieved better TM cellularity. In cultured human TM cells, GBE substantially attenuated anti-Fas ligand-induced apoptosis and reduced DEX-induced myocilin expression. Ginkgo biloba extract modulated the expression of alphaB-crystallin and heat-shock proteins 70 and 90alpha but not other stress-related genes. Furthermore, changes associated with DEX were found less in GBE-treated or GBE-primed TM cells. CONCLUSION: We showed that GBE, a nontoxic, antiapoptotic, herbal compound significantly suppressed steroid-induced IOP elevation in rabbits and it seems to prevent the adverse effects of DEX on TM cells. CLINICAL RELEVANCE: Ginkgo biloba extract could be a therapeutic agent or dietary supplement to prevent steroid-induced ocular hypertension.

Supplements and age-related eye conditions the beaver dam eye study.

OBJECTIVE: To investigate the association of use of vitamin, mineral, and nonvitamin nonmineral supplements with common age-related eye diseases. DESIGN: Population-based prospective study with incidence data. PARTICIPANTS: Subjects were participants in the Beaver Dam Eye Study who contributed data in 1988 to 1990 (n = 4926), 1993 to 1995 (n = 3722), 1998 to 2000 (n = 2962), and 2003 to 2005 (n = 2375). METHODS: Use of all medications and supplements were collected from study participants at each of 4 examinations. Intraocular pressure (IOP) measurement and fundus and lens photography were done at each visit. Visual field data are available only from baseline. Photographs of the lenses, retina, and discs were graded using standard protocols by trained graders. MAIN OUTCOME MEASURES: Incidence of age-related cataracts, macular degeneration (AMD), and high IOP for one set of analyses and incidence of supplement use for the second set of analyses. RESULTS: There was little evidence of any significant associations between supplement use and incident ocular outcomes except for a small protective effect for cortical cataracts by vitamins A and D, zinc, and multivitamins and increased odds of late AMD. Late AMD was associated with incident use of vitamins A, C, and E and zinc. CONCLUSIONS: Age-related macular degeneration seems to precede use of vitamins A, C, and E and zinc. This may reflect advice by family, friends, and health care providers about the benefits of Age-Related Eye Disease Study-like supplements.

Tratamiento acupuntural de urgencia para el control de la presión intraocular en el glaucoma / Emergency acupuncture treatment for controlling intraocular pressure in glaucoma

Se realizó una intervención terapéutica de fase II, aleatorizada y unicéntrica, dirigida a validar la eficacia del tratamiento acupuntural de urgencia para controlar la presión intraocular en 64 pacientes con glaucoma primario de ángulo abierto descompensado, que acudieron a la consulta de Oftalmología de la Policlínica Docente Josué País García de Santiago de Cuba desde febrero hasta junio del 2006 y fueron asignados a uno de los 2 grupos: de estudio y control, con 32 integrantes por igual. Se analizaron las siguientes variables: edad, sexo, tiempo de evolución de la enfermedad, relación copa-disco, presión intraocular inicial y final, diagnóstico sindrómico según medicina tradicional asiática, efectos adeversos y respuesta terapéutica. La evaluación de los resultados reveló que, en sentido general, no hubo diferencias significativas entre ambos grupos y que el tratamiento acupuntural de urgencia fue tan eficaz como el medicamentoso con acetazolamida sódica por vía endovenosa para equilibrar la presión intraocular en dichos pacientes(AU)

A randomized and unicentric phase II therapeutic intervention was carried out to validate the effectiveness of the emergency acupuncture treatment for controlling intraocular pressure in 64 patients with decompensated primary open-angle glaucoma, who attended the Ophthalmology Department of the Josué País García Teaching Polyclinic of Santiago de Cuba from February to June, 2006. They were divided into 2 groups (study and control groups) of 32 patients each. The following variables were analyzed: age, sex, time of the disease progression, cup-disk ratio, initial and final intraocular pressure, syndromic diagnosis according to Asian traditional medicine, adverse effects and therapeutic response. In general, the evaluation of results revealed no significant differences between the groups, and emergency acupuncture treatment was as effective as intravenous therapy with sodium acetazolamide to balance intraocular pressure in these patients

Effect of the Honan intraocular pressure reducer in sub-Tenon's anesthesia.

PURPOSE: To ascertain whether the Honan intraocular pressure reducer (HIPR) has an effect on the preoperative intraocular pressure (IOP), surgeon's assessment of anesthesia, and patients' analgesic experience when sub-Tenon's anesthesia is used for routine cataract surgery. SETTING: Princess Alexandra Eye Pavilion, Edinburgh, Scotland. METHOD: Forty-five eyes of 45 patients having routine phacoemulsification cataract surgery were randomized to receive 10 minutes of ocular compression using the HIPR or no compression after administration of sub-Tenon's anesthesia. The IOP was measured immediately before and immediately and 10 minutes after sub-Tenon's anesthesia administration using a standard technique. One surgeon who was masked to the randomization process performed all injections and completed a questionnaire on aspects of the anesthetic block. Patients scored their level of analgesia during surgery. RESULTS: The mean rise in IOP immediately after administration of sub-Tenon's anesthesia was 1.39 mm Hg +/- 3.91 (SD) (95% confidence interval +0.22 to 2.57; P =.021). In the 22 patients who received compression, there was a mean IOP reduction of 4.20 +/- 2.74 mm Hg at 10 minutes. The mean difference between the compression and no-compression groups at 10 minutes was 4.99 mm Hg (P<.0001). There was no difference in the surgeon's scores for any aspect of the sub-Tenon's anesthesia (P>.05). All patients reported good levels of analgesia. CONCLUSIONS: There was a significant reduction in IOP after compression using the HIPR. However, the rise in IOP after administration of sub-Tenon's anesthesia was small and the use of the HIPR did not make a significant difference in the effectiveness of the anesthesia to the surgeon or patients.

The Ginkgo biloba extract (EGb 761) provides a neuroprotective effect on retinal ganglion cells in a rat model of chronic glaucoma.

PURPOSE: To investigate the effect of Ginkgo biloba extract (EGb 761) against neurotoxicity of retinal ganglion cells of rats with chronic moderately elevated intraocular pressure (IOP). METHODS: Unilateral chronic moderately elevated IOP was produced in rats by cautery of three episcleral vessels. Secondary degeneration was measured with and without EGb 761 for 5 months. At 5 months, retinal ganglion cells were labeled with a fast blue tracer applied to both superior colliculi. Densities of surviving retinal ganglion cells were estimated by counting fast blue labeled cells in whole mounted retinas. RESULTS: When compared with their contralateral control eyes with normal IOP, in the peripheral retina, retinal ganglion cell loss in eyes with chronic, moderately elevated IOP was 29.8 +/- 1.5% (n=5) at 5 months in untreated animals and 4.6 +/- 4.5% (n=5) at 5 months in treated animals with EGb 761. CONCLUSIONS: Pretreatment and early posttreatment with EGb 761 is an effective neuroprotectant in a rat model of chronic glaucoma.

AL-2512, a novel corticosteroid: preclinical assessment of anti-inflammatory and ocular hypertensive effects.

The anti-inflammatory efficacy and ocular hypertensive effect of AL-2512 were characterized in rodent and feline models of ocular inflammation. Neutrophil influx into ocular tissue following topical ocular administration of test drugs was evaluated in models of endotoxin-induced uveitis. In rats, the anti-inflammatory efficacy of AL-2512 was compared with that of 0.1% dexamethasone. Test drug or vehicle was administered topically before subplantar injection of endotoxin. Neutrophil influx was assessed at 24 hours. Feline eyes, injected intravitreally with endotoxin, were treated topically with 0.1% AL-2512, 1.0% prednisolone acetate or vehicle at various timepoints before and after endotoxin injection. At 12 hours, protein concentration and leukocyte count in aqueous humor were determined. In the feline intraocular pressure (IOP) model, after baseline IOP values were established, AL-2512, dexamethasone, or vehicle was administered topically to both eyes of cats. IOP was measured daily before and during treatment. Topical ocular administration of AL-2512 inhibited endotoxin-induced leukocyte influx in rodent and feline models of uveitis. In rats, AL-2512 significantly inhibited neutrophil influx by 89%, compared with 93% by dexamethasone. In feline eyes, AL-2512 significantly (p < 0.05) inhibited leukocyte infiltration of aqueous humor by 59%, compared to 37% inhibition by prednisolone acetate. Intraocular pressure in cats treated for 32 days with AL-2512 or dexamethasone increased 6% and 18%, respectively. The ocular anti-inflammatory effect of AL-2512 was equivalent to dexamethasone and superior to prednisolone acetate in rat and feline models of ocular inflammation, respectively. This steroid provides anti-inflammatory efficacy equivalent to dexamethasone with a reduced risk of inducing ocular hypertension.

Neuroprotective effect of treatment with calcium antagonists on hypertensive retina.

The influence of hypertension and of treatment with the dihydropyridine-type Ca2+ antagonists lercanidipine, manidipine, nicardipine, and nimodipine and with non dihydropyridine-type vasodilator hydralazine on retinal nervous and glial fibrillary acidic protein (GFAP) immunoreactive astrocytes were investigated in male spontaneously hypertensive rats (SHR). Normotensive Wistar-Kyoto (WKY) were used as normotensive references group. Treatment of animals with oral equi-hypotensive doses of the above compounds started at 14 weeks of age and lasted for 12 weeks. Microanatomical analysis was extended to samples of frontal cortex and occipital cortex used as reference tissue. Different compounds investigated decreased to a similar extent systolic blood pressure values with the exception of nimodipine that in spite of the high dose used exerted a less pronounced hypotensive activity. Morphological changes including reduced thickness of retina and of inner plexiform, outer nuclear and layer of inner and outer segments plus outer limiting layer, and loss of ganglionic neurons were observed. GFAP-immunoreactive astrocyte hypertrophy was also found in control SHR. These phenomena were countered by treatment by treatment with dihydropyridine-type Ca2+ antagonists and to a lesser extent by hydralazine. The different Ca2+ antagonists tested exerted a similar protective effect on retinal, but not on brain neurons. The sensitivity of retina and cerebral cortex to anti-hypertensive treatment may be related to a different density of L-type Ca2+ channels in structures investigated or to kinetic reasons. The demonstration of a neuroprotective effect of Ca2+ antagonists on retina of SHR suggests that these compounds might protect to a some extent retina from hypertensive injury.

Effect of Honan balloon compression on peribulbar anesthesia adequacy in cataract surgery.

PURPOSE: To ascertain whether a Honan balloon is necessary to produce effective peribulbar anesthesia in routine cataract surgery by evaluating its effect on intraocular pressure (IOP), surgeon assessment of the anesthesia's effectiveness, and patients' analgesic experience. SETTING: West of England Eye Unit, Royal Devon and Exeter Hospital, England. METHOD: Fifty eyes of 50 patients having routine phacoemulsification cataract extraction and intraocular lens implantation were randomized to have 10-minute ocular compression with the Honan balloon or no compression after peribulbar anesthesia. A single investigator gave all the peribulbar injections using a standard technique. The IOP was measured immediately before and 10 minutes after the injections. Two surgeons who were blinded to the randomization process performed the surgeries and completed an assessment questionnaire on various aspects of the peribulbar block. The patients also scored their level of analgesia during surgery. RESULTS: In the 26 patients who had Honan balloon compression, there was a significant reduction in IOP (mean 6.2 mm Hg; P <.05). In the 24 patients with no balloon compression, there were no significant changes in IOP 10 minutes after the peribulbar injections. There was no statistically significant difference in the surgeons' scores in any aspect of the peribulbar anesthesia (P >.05). All patients experienced a good level of analgesia. CONCLUSIONS: There was a significant reduction in IOP after Honan balloon ocular compression. However, there was no significant increase in IOP without balloon compression. The use of a Honan balloon did not appear to make a significant difference in the effectiveness of the peribulbar anesthesia to the surgeons or patients.

Vaccination for protection of retinal ganglion cells against death from glutamate cytotoxicity and ocular hypertension: implications for glaucoma.

Our group recently demonstrated that autoimmune T cells directed against central nervous system-associated myelin antigens protect neurons from secondary degeneration. We further showed that the synthetic peptide copolymer 1 (Cop-1), known to suppress experimental autoimmune encephalomyelitis, can be safely substituted for the natural myelin antigen in both passive and active immunization for neuroprotection of the injured optic nerve. Here we attempted to determine whether similar immunizations are protective from retinal ganglion cell loss resulting from a direct biochemical insult caused, for example, by glutamate (a major mediator of degeneration in acute and chronic optic nerve insults) and in a rat model of ocular hypertension. Passive immunization with T cells reactive to myelin basic protein or active immunization with myelin oligodendrocyte glycoprotein-derived peptide, although neuroprotective after optic nerve injury, was ineffective against glutamate toxicity in mice and rats. In contrast, the number of surviving retinal ganglion cells per square millimeter in glutamate-injected retinas was significantly larger in mice immunized 10 days previously with Cop-1 emulsified in complete Freund's adjuvant than in mice injected with PBS in the same adjuvant (2,133 +/- 270 and 1,329 +/- 121, respectively, mean +/- SEM; P < 0.02). A similar pattern was observed when mice were immunized on the day of glutamate injection (1,777 +/- 101 compared with 1,414 +/- 36; P < 0.05), but not when they were immunized 48 h later. These findings suggest that protection from glutamate toxicity requires reinforcement of the immune system by antigens that are different from those associated with myelin. The use of Cop-1 apparently circumvents this antigen specificity barrier. In the rat ocular hypertension model, which simulates glaucoma, immunization with Cop-1 significantly reduced the retinal ganglion cell loss from 27.8% +/- 6.8% to 4.3% +/- 1.6%, without affecting the intraocular pressure. This study may point the way to a therapy for glaucoma, a neurodegenerative disease of the optic nerve often associated with increased intraocular pressure, as well as for acute and chronic degenerative disorders in which glutamate is a prominent participant.

[Intraocular pressure after phacoemulsification and implantation of silicone plate haptic intraocular lenses without viscoelastics]. / Intraokulardruck nach Phakoemulsifikation mit Implantation einer Silicon-Plattenhaptik-Intraokularlinse ohne Viskoelastika.

BACKGROUND: A rise in intraocular pressure (IOP) after cataract operation is a well known problem. Avoidance of the use of viscoelastics seems to solve the problem. PATIENTS AND METHODS: The IOP was measured in a group of 33 eyes of 33 patients one day before, as well as 6 hours, 24 hours, and 7 days after phacoemulsification and implantation of a foldable silicone plate haptic intraocular lens without viscoelastics and by means of an injector and of the anterior chamber maintainer. RESULTS: Mean preoperative IOP was 16.1 +/- 3.9 mm Hg (range 10 to 28 mm Hg). Postoperatively mean IOP was 12.3 +/- 3.3 mm Hg (range 5 to 18 mm Hg) after 6 hours (p < 0.0001), 13.8 +/- 2.8 mm Hg (range 7 to 19 mm Hg) after 24 hours (p = 0.032), and 15.5 +/- 3.4 (range 10 to 24) after one week (p = 0.39). In none of the eyes was the pressure in the first 24 hours higher than 18 mm Hg. When excluding the 4 patients with glaucoma and PEX or when taking them as a separate group, the results were similar. CONCLUSIONS: Pressure elevation after cataract operation without the use of viscoelastic substances can be avoided, thus contributing not only to lower costs but also to a higher safety.

[Topical laryngo-tracheal anesthesia and intraocular pressure in anesthesia for ophthalmic surgery]. / Anestesia topica laringo-tracheale e pressione intraoculare in anestesia per la oftalmochirurgia.

OBJECTIVE: The reflex response to orotracheal intubation provokes an increase of arterial pressure accompanied by an increase of chorioides volume and a consequent ocular hypertone. There are several methods to reduce the reflex response due to intubation. One of the most effective is topical anaesthesia of larynx and trachea. Experiments were directed to evaluate the efficacy of topical anaesthesia to reduce the intraocular hypertone due to orotracheal intubation. DESIGN: A prospective randomized mask study was conduct on patients undergoing ophthalmologic (anterior segment) surgery at the Eye Clinic of Florence University. METHODS: Intraocular pressure was measured by a Goldman tonometer at four times: T0 = basal, T1 = 2' minutes after induction of general anaesthesia, T2 = 2' minutes after laryngoscopy, T3 = 2' minutes after orotracheal intubation. At the same moments, systolic blood pressure, heart rate, rate pressure pro duct were measured. Patients were randomly divided in two groups: Group L (n = 10) in which was evaluated the efficacy of laryngotracheal topical spray of lidocaine 4% (2 ml) and Group F (n = 10) in which saline was used instead of anesthetic. The filling of the LTA kit (Abbott) was made by a person not involved in the experiments. DATA ANALYSIS: Student's t test for unpaired data. RESULTS: Topical anaesthesia reduces the increase of intraocular pressure, hypertension and rate pressure product due to intubation. The intraocular pressure reduces to 13% less than basal value in Group L and increase to 50% more than basal value in Group F. CONCLUSION: The topical anaesthesia of larynx and trachea is effective to reduce the intraocular hypertension due to the reflex response evoked by orotracheal intubation.

[Effect of preoperative intraocular pressure on the course of cataract extraction]. / Wplyw przedoperacyjnego cisnienia wewnatrzgalkowego na przebieg usuniecia zacmy.

The connection between the values of the intraocular pressure before cataract surgery and the number of intraoperative complications was checked. It was established that the preoperative hypotony improves in an essential manner the operative conditions and influences favourably the decrease of the number of complications in the course the surgery. It was confirmed that the manual massage of the eye is equally efficient and less influencing generally the patient than the pharmaceutical lowering of the IOP.