Influence of sex on chronic steroid-induced glaucoma: 24-Weeks follow-up study in rats.

The objective was to evaluate ocular changes based on sex in steroid-induced glaucoma models in rats comparing healthy controls, over 24 weeks follow-up. Eighty-nine Long-Evans rats (38 males and 51 females) with steroid-induced glaucoma were analysed. Two steroid-induced glaucoma models were generated by injecting poly-co-lactic-glycolic acid microspheres loaded with dexamethasone (MMDEX model) and dexamethasone-fibronectin (MMDEXAFIBRO model) into the ocular anterior chamber. Intraocular pressure was measured by rebound tonometer Tonolab®. Neuroretinal function was analysed using dark- and light-adapted electroretinography (Roland consult® RETIanimal ERG), and structure was analysed using optical coherence tomography (OCT Spectralis, Heidelberg® Engineering) using Retina Posterior Pole, Retinal Nerve Fibre Layer and Ganglion Cell Layer protocols over 24 weeks. Males showed statistically (p < 0.05) higher intraocular pressure measurements. In both sexes and models neuroretinal thickness tended to decrease over time. In the MMDEX model, males showed higher IOP values and greatest percentage thickness loss in the Ganglion Cell Layer (p = 0.015). Females receiving MMDEXAFIBRO experienced large fluctuations in thickness, a higher percentage loss (on average) in Retina Posterior Pole (p = 0.035), Retinal Nerve Fibre Layer and Ganglion Cell Layer than aged-matched males, and the highest thickness loss rate by mmHg. Although no difference was found by sex in dark- and light-adapted electroretinography, increased amplitude in photopic negative response was found in MMDEX males and MMDEXAFIBRO females at 12 weeks. Although both glaucoma models used dexamethasone, different intraocular pressure and neuroretinal changes were observed depending on sex and other influential cofactors (fibronectin). Both sex and the induced glaucoma model influenced neuroretinal degeneration.

Long-term corticosteroid-induced chronic glaucoma model produced by intracameral injection of dexamethasone-loaded PLGA microspheres.

PURPOSE: To evaluate a new chronic glaucoma model produced by intracameral injection of dexamethasone-loaded poly lactic-co-glycolic acid microspheres (Dex-PLGA-Ms) over six months. METHODS: Healthy rats received two injections (at baseline and Week 4) of Dex-PLGA-Ms into the anterior chamber of the right eye. Clinical signs and intraocular pressure (IOP) were weekly recorded. The structure of the retina and optic nerve was in vivo evaluated using optical coherence tomography (OCT) every two weeks and functionally using dark- and light-adapted electroretinography at 0-12-24 weeks. Histological studies were also performed. RESULTS: IOP progressively increased up to hypertension (23.22 ± 3.63 mmHg) in both eyes but did so later in left eyes. OCT quantified a decrease in full-thickness retina posterior pole (R), retinal-nerve-fiber layer (RNFL), and ganglion-cell layer (GCL) thickness up to 24 weeks. Right eyes showed higher neuroretinal thickness loss up to week 8. RNFL experienced the highest percentage thickness loss at the inferior-superior axis, while in GCL the inner sectors of the horizontal axis (Nasal-Temporal) suffered the greatest decrease in thickness. Retinal ganglion cell, photoreceptor, and intermediate cell functionality decreased over time. Increased deposition of collagen IV was also found in zonular fibers and the ciliary body. CONCLUSIONS: This work shows the usefulness of drug delivery systems, not to treat pathology but to induce it. Only two injections of Dex-PLGA-Ms in the anterior chamber of rat eyes were enough to progressively create ocular hypertension and subsequent functional and structural neuroretinal degeneration, at least over 6 months.

Brimonidine-LAPONITE® intravitreal formulation has an ocular hypotensive and neuroprotective effect throughout 6 months of follow-up in a glaucoma animal model.

Intravitreal administration is widely used in ophthalmological practice to maintain therapeutic drug levels near the neuroretina and because drug delivery systems are necessary to avoid reinjections and sight-threatening side effects. However, currently there is no intravitreal treatment for glaucoma. The brimonidine-LAPONITE® formulation was created with the aim of treating glaucoma for extended periods with a single intravitreal injection. Glaucoma was induced by producing ocular hypertension in two rat cohorts: [BRI-LAP] and [non-bri], with and without treatment, respectively. Eyes treated with brimonidine-LAPONITE® showed lower ocular pressure levels up to week 8 (p < 0.001), functional neuroprotection explored by scotopic and photopic negative response electroretinography (p = 0.042), and structural protection of the retina, retinal nerve fibre layer and ganglion cell layer (p = 0.038), especially on the superior-inferior axis explored by optical coherence tomography, which was corroborated by a higher retinal ganglion cell count (p = 0.040) using immunohistochemistry (Brn3a antibody) up to the end of the study (week 24). Furthermore, delayed neuroprotection was detected in the contralateral eye. Brimonidine was detected in treated rat eyes for up to 6 months. Brimonidine-LAPONITE® seems to be a potential sustained-delivery intravitreal drug for glaucoma treatment.

Hemorrhagic retinopathy in newborns: frequency, form of presentation, associated factors and significance.

During the first 72 hours of their lives, 420 neonates were checked for retinal hemorrhages and macular affection. The neonate's gestational age, birth weight, and Apgar scores and maternal data (nulliparty, fetal presentation, duration of labor and delivery, induction of labor and obstetric technique) were all recorded. In 81 cases (19.2%), retinal hemorrhages were found. No significant relation was established with any of the associated factors, except for a significantly lower frequency of hemorrhages in cases of cesarean delivery (p < 0.01) and a significantly longer expulsive phase in the group with hemorrhages (p < 0.05). In follow-up examination 3 to 4 months later, neither the infants with hemorrhages nor the control group presented alterations.

[Study of infectious keratitis in corneal graft]. / Estudio de la queratitis infecciosa en el injerto corneal.

PURPOSE: This retrospective study was conducted to identify the associated risk factors and microbiologic spectrum in infectious keratitis (IK) after penetrating keratoplasty (PK). METHODS: Medical records of 246 PK (corneal grafts for a 17-year period, 1980-1997) were reviewed to identify IK. Criterion for inclusion was IK in PK and positive corneal culture or smear Gram stain. PK indications, interval PK-IK, risk associations microbiologic study, complications, and final corneal graft clarity were reviewed. RESULTS: The incidence reported was 4.8%, 12 cases of IK identified in 246 PK performed. The most common PK diagnosis was herpes simplex keratopathy. Potential risk factors have been categorized in :1- Local ocular (graft discompensation, therapeutic contact lens, suture-related), 2- Topical medication (corticosteroids and antibiotics) and 3- Systemic causes (diabetes mellitus). Time interval between PK-IK was 27.1+/-25.7 months (25% occurred within 12 months PK and suture complications were the main cause; 75% later than 12 months and corneal oedema and therapeutic contact lens the main late causes). Microbial spectrum: 66.6% cases were bacterial, Gram (+) organisms were predominantly involved (Streptococcus and Staphylococci) and the remaining cases were fungal (Candida). There was one case of infectious crystalline keratopathy due to Streptococcus Mitis. The prevalence of complications like evisceration and failure clear graft were 75%. CONCLUSIONS: IK after PK is an uncommon (4.8%) but serious complication. It proves a major later form incidence, associated to graft discompensation and contact lens use. Gram (+) bacterial organism and fungi (Candida) were predominantly involved.

[Descriptive study of autopsies of internal medicine department at the hospital of Barbastro and clinico-pathological correlation]. / Estudio descriptivo de las autopsias del Servicio de Medicina Interna del Hospital Comarcal de Barbastro y correlación clínico-patológica.

BACKGROUND: To review the autopsies of Internal Medicine Department at the Hospital of Barbastro and to compare clinical and pathological diagnosis. MATERIAL AND METHODS: Retrospective study of 51 consecutive autopsies performed between April 1989 to December 1996 is carried out. Clinico-pathological correlation is stablished with the underlying cause of death distinguishing among concordance and severe (with adverse impact on survival) or mild discrepancy. RESULTS: The autopsy rate was 6.6% in that period. 70.5% were male. The median of the age was 70. Severe yatrogenia was found in one case. Respiratory diseases (23.5%) followed by cardiovasculars (19.6%) and infections (17.6%) were the most frequents underlying cause of death. Pulmonary thromboembolism was demonstrated in 37.2%, being massive only in 7.8%. Discrepancies were found in 31% of cases, 25% mild and 6% severe. CONCLUSIONS: Our data are similar to other studies but differ essentially in a lesser number of severe discrepancies in our findings and also in the frequency of the groups of diseases (there are more infections and tumours in other series) attributed to the hospital features and to the oldness of the studied population, among others.

[Cogan's syndrome]. / Síndrome de Cogan. Presentación de un caso.

The association of non syphilitic interstitial keratitis with vestibulo-auditory symptoms was first described by Cogan in 1945. Owing to the rarity of this condition our opportunity of dealing with one of such cases is the reason for this paper, in which are contemplated besides the review of the published literature other points concerning the etiopathogenesis, the treatment and the follow-up of the disease.

[Ophthalmological exploration of children with Down's syndrome. Main results and comparison with a control group]. / Exploración oftalmológica en niños con síndrome de Down: principales resultados y comparación con un grupo control.

BACKGROUND: Down's Syndrome is the most frequent chromosomal aberration. There is a wide variety of symptoms. From an ophthalmological point of view, numerous alterations associated with Down's Syndrome have been described. MATERIAL AND METHODS: We have carried out a complete ophthalmic exploration on 60 children with Down's Syndrome and 60 control children. RESULTS: The first group showed a high percentage of refraction errors (90%), nystagmus (28%), strabismus (48%) and cataracts (13%). If we compare these results with those of the control group we find that the Down's group has a frequency significantly higher both in refraction errors as a whole (p < 0.001) and myopia (p < 0.01), hypermetropia (p < 0.02) and stigmatism (p < 0.001). They have also shown a frequency significantly higher of strabismus (p < 0.001). CONCLUSION: All of the observed alterations can have a negative influence on the appropriate educational development of these children. An early ophthalmological exploration would be advisable in children with Down's Syndrome.