Acácio Alves de Souza Lima Filho

Effects of intravitreal triamcinolone acetonide injection with and without preservative

Aims: To evaluate the effects of intravitreal injection of preservative-free triamcinolone acetonide (PFTA) and TA containing preservative (KE). Methods: A retrospective review was conducted of 646 intravitreal 4 mg/0.1 ml steroid injections in 471 eyes. A total of 577 intravitreal injections of PFTA and 69 injections of KE were administered in non-randomised eyes. No supernatant removal from KE was performed. Non-infectious endophthalmitis was defined as pseudohypopyon/hypopyon with or without an inflammatory reaction that regressed after steroid eye drop instillation. Ocular hypertension was defined as more than 23 mm Hg with Goldman applanation tonometry. Patients were followed and examined 1, 7 and 28 days, and 3, 4, 6 and 12 months after injection and annually thereafter. Statistical analysis was performed using Fisher’s exact test and &KHgr;2 test. p Values <0.05 were considered significant. Results: Both groups did not differ in demographics (p>0.05). Follow-up ranged from 6 to 57 months (mean 13, SD 7.5). Ocular hypertension was present in 127 eyes (20%), but both groups did not differ significantly (p = 0.167). Four eyes (3.15%) required trabeculectomy. Non-infectious endophthalmitis developed in 12 eyes (1.9%) and varied significantly in both groups (p = 0.005). One eye developed bacterial endophthalmitis (0.15%). Conclusions: Non-infectious endophthalmitis was observed significantly more often after KE injections (7.3%) than after PFTA injections (1.2%) (p<0.05). An inflammatory reaction was more clinically relevant in the KE group than in the PFTA group.

Análise ultraestrutural e de fatores de crescimento de diferentes métodos de preservação da membrana amniótica utilizada em cirurgia ocular

PURPOSE: To compare the anatomical structure and the presence of growth factors and cytokines of amniotic membrane preserved in glycerol/MEM (1:1) or undiluted dimethyl sulfoxide through electron microscopy. METHODS: Amniotic membrane preserved in glycerol/MEM (1:1) or undiluted dimethyl sulfoxide were processed for transmission and scaning electron microscopy. As control, freshly collected amniotic membrane was fixed and processed for electron microscopy. The cytokines and growth factors assessed were: TGF-b (transforming growth factor b); TGF-b activ (activated transforming growth factor b); EGF (epidermal growth factor); FGF-4 (fibroblast growth factor 4); bFGF (basic fibroblast growth factor); IL-4 (interleukin 4); PGE2 (prostaglandin E2); IL-10 (interleukin 10); KGF (keratinocyte growth factor); HGF (hepatocyte growth factor). RESULTS: Amniotic membrane from the control group showed intact epithelium, with surface microvilli and junctional complexes between the cells and the basal membrane. Glycerol/MEM preserved amniotic membrane had similar aspect to the control, with higher epithelial cells. Those amniotic membranes preserved in dimethyl sulfoxide disclosed less intercellular junction and detachment of the epithelium from the basal membrane. The cytokines and growth factors did not disclose significant differences, except for FGF-4, bFGF, PGE2 and KGF. CONCLUSIONS: Amniotic membrane preserved in glycerol/MEM showed a better tissue structure, with less detachment of the epithelium from the basal membrane, in comparison to undiluted dimethyl sulfoxide. The majority of the growth factors and cytokines were kept with both techniques of preservation.

Biochemical analysis and decomposition products of indocyanine green in relation to solvents, dye concentrations and laser exposure.

Purpose: To investigate pH, ions, osmolarity and precipitation of indocyanine green (ICG), as well as the profile of ICG decomposition products (DPs) after laser exposure and the interaction with quenchers. Methods: ICG was diluted in water, 5% glucose (GL) or balanced salt solution (BSS) to achieve concentrations of 2.5, 1, 0.25 and 0.1 mg/ml. Osmolarity, pH and precipitation were analyzed immediately and after 24 h. Precipitation analyses were done with a scanning electron microscope. Anion and iodate analyses of ICG and infracyanine green (IfCG) were performed by capillary zone electrophoresis. With regard to DPs, 0.5 mg/ml of ICG was assessed with high-performance liquid chromatography (HPLC) after 810-nm laser irradiation. DP profiles were evaluated with ICG dilution in quenchers (Trolox, histidine and DABCO) in 3 concentrations (0.1, 1 and 10 M). Results: BSS promoted iso-osmotic ICG solutions of 208 mOsm (147-266) compared to GL with 177 mOsm. BSS solutions had a higher physiological pH of 7.2 compared with the GL one of 6.55. ICG precipitated more when diluted with BSS (5.95 mg); in contrast, GL showed less precipitate (3.6 mg). IfCG has no iodine derivates and other ICGs have an average 4.6% of iodate derivates. From HPLC analysis, 5 DPs were observed. The rate of DPs was higher when BSS was used (p < 0.05). Five DPs have been generated with ICG, and they may be altered with the quenchers DABCO, histidine and Trolox. Conclusions: BSS dilution induces more precipitation and DPs. ICG dilution in any solvent induces DPs. Quencher use reduces the amount of toxic DPs.

Freeze-drying as an alternative method of human sclera preservation

PURPOSE To compare the effect of preserving sclera samples in either 95% ethanol or freeze-dried. METHODS Ninety-six samples of human sclera were studied. Half of them were freeze-dried and half preserved in 95% ethanol. Preservation periods of 18, 45, 90 or 174 days were studied. Automated immunostaining was carried out in the Ventana BenchMarkR LT platform using collagen 1 and fibronectin antibodies. Histological staining was also performed with hematoxilin-eosin and Masson trichrome. Samples were classified according to the degree of collagen fiber parallelism (0-2), intensity of Masson staining (0-2), and the expression of both antibodies (0-3). Friedman and Wilcoxon tests were applied to compare preservation methods and p-values below 0.05 were considered to ensure statistical significance. RESULTS Relevant results were found in three situations: (i) Friedmans test showed better collagen fiber integrity in the freeze-dried group rehydrated after 174-days as compared to the 90-day group; (ii) Wilcoxons test showed better collagen fiber integrity in the freeze-dried group after 18 and 174 days as compared to the ethanol group; (iii) the freeze-dried group disclosed higher immunohistochemical expression for COL-1 antibody in the sclera samples rehydrated after 45, 90 and 174 days as compared to the ones rehydrated after 18 days. CONCLUSION Histological and immunohistochemical analysis showed freeze-drying to be a superior method for sclera preservation as compared to 95% ethanol. This technique provides an easy method to manipulate tissue, with longer shelf life, and storage at room temperature.

Bupivacaine and botulinum toxin to treat comitant strabismus

PURPOSE To evaluate the change in ocular motility and muscle thickness measured with ultrasonography after intramuscular injection of bupivacaine and botulinum toxin A. METHODS Eight patients (five female) were enrolled to measure ocular motility prior and 1, 7, 30 and 180 days after one injection of 2 ml of 1.5% bupivacaine and 2.5 U of botulinum toxin A in agonist and antagonist muscles, respectively, of eight amblyopic eyes. Muscle thickness was measured prior and on days 1, 7 and 30 after injection using 10-MHz ultrasonography (eyelid technique). RESULTS Mean change in alignment was 10 prism diopters after 180 days (n=6). An average increase of 1.01 mm in muscle thickness was observed after 30 days of bupivacaine injection and 0.28 mm increase was observed after botulinum toxin A injection, as measured by ultrasonography. Lateral rectus muscles injected with bupivacaine had a mean increase of 1.5 mm in muscle thickness. CONCLUSION In this study, a change in ocular motility was observed after 180 days of intramuscular injection of bupivacaine and botulinum toxin in horizontal extraocular muscles. Overall, there was an increase of muscle thickness in both botulinum toxin A and bupivacaine injected muscles after 30 days of injection when measured by ultrasonography. This change was more pronounced on lateral rectus muscles after bupivacaine injection.

Aqueous humor concentrations of topical fluoroquinolones alone or in combination with a steroid

PURPOSE To compare the aqueous humor (AH) concentrations of moxifloxacin 0.5% and gatifloxacin 0.3% solutions alone or when treatment was combined with steroids, and to correlate these concentrations with the minimum inhibitory concentrations (MIC) for the most common endophthalmitis-causing organisms. METHODS Patients undergoing phacoemulsification were enrolled to receive one drop of one of the following solutions: moxifloxacin (G1), moxifloxacin + dexamethasone (G2), gatifloxacin (G3), or gatifloxacin + c (G4), every 15 min, 1h before surgery. AH samples were collected before surgery and analyzed using HPLC-tandem mass spectrometry. RESULTS The mean antibiotic concentrations in the AH were: G1= 1280.8 ng/mL; G2= 1644.3 ng/mL; G3= 433.7 ng/mL; and G4= 308.1 ng/mL. The mean concentrations statistically differed between G1 and G2 (p=0.01), and G3 and G4 (p=0.008). All samples achieved the MIC for Staphylococcus epidermidis; 100% of the samples from G1 and G2, and 97% from G3 and G4 reached the MIC for fluoroquinolone-sensitive Staphylococcus aureus; 100% of the samples from G1 and G2, 88% from G3, and 72% from G4 reached the MIC for enterococci (p<0.001); and 100% of samples from G1 and G2, 59% from G3, and 36% from G4 reached the MIC for Streptococcus pneumoniae (p<0.001). For fluoroquinolone-resistant S. aureus, 23% from G1, 44% from G2, and no samples from G3 or G4 achieved the MIC (p<0.001). CONCLUSIONS Moxifloxacin + dexamethasone demonstrated a higher concen-tration in the AH than the moxifloxacin alone. Gatifloxacin + steroids demonstrated less penetration into the anterior chamber than gatifloxacin alone. Moxifloxacin was superior to gatifloxacin considering the MIC for enterococci, S. pneumoniae, and fluoroquinolone-resistant S. aureus.

Preoperative tranilast as adjunctive therapy to primary pterygium surgery with a 1-year follow-up

PURPOSE To determine the efficacy of tranilast as an adjunctive therapy in conjunctival autograft. METHODS Twenty-nine patients were randomly allocated to the Tranilast Group (n=15) or the Control Group (n=14). The Tranilast Group received a subconjunctival injection of 0.5% tranilast 30 days prior to surgery. Conjunctival autograft was performed in both groups using fibrin sealant and 0.02% subconjunctival mitomycin C at the end of the surgery. After the resection of the pterygium, immunohistochemistry was performed with 100 cells to identify epithelial cells positive for transforming growth factor-β (TGF-β). Subjective symptoms were evaluated using a 5-point scale, and the recurrence rate was assessed. RESULTS Both groups showed improvements in their symptoms and similar clinical results. Compared with the Control Group, the Tranilast Group failed to show a decreased recurrence rate (p=0.59). However, the number of epithelial cells expressing TGF-β was lower in the Tranilast Group (5 cells; 95% CI: 2.56-13.15; Control Group, 16 cells, 95% CI: 11.53-24.76; p=0.01). Minimal but reversible complications, including glaucoma secondary to corticosteroids and granuloma, occurred during the study. CONCLUSION Tranilast was effective in decreasing the number of pterygium epithelial cells expressing TGF-β.

Nature as a source of drugs for ophthalmology

Nature has always provided an unlimited source of biologically-active compounds. Since the beginning of mankind, humans have sought resources in fauna and flora to treat eye diseases. However, it was only after the Industrial Revolution that extracts of plants and substances of animal origin could be used safely, as has been determined by controlled interventional studies. Two major challenges faced by ocular pharmacology are the following: developing drugs that are able to reduce blindness due to glaucoma; and controlling the pain associated with eye surgery. The search for a drug that effectively lowers intraocular pressure and controls the progression of glaucoma has led to the development of various ocular hypotensive agents, such as physostigmine from the Physostigma venenosum plant. The anesthetic properties of cocaine, extracted from Erythroxylon coca, finally enabled surgical procedures in the eye. Several new natural compounds have been investigated in an attempt to identify substances with the potential to provide additional benefits to eye tissue and vision. Emerging evidence of anti-inflammatory, wound-healing, antimicrobial, antioxidant, antitumor, and antiangiogenic properties attributed to plant extracts and animal tissues has encouraged more investment in research in this area. Despite technological advances in synthesizing drugs, the pharmaceutical industry still seeks new active compounds from natural sources as well as from revisiting already-established naturally derived compounds. Although a large number of naturally-occurring compounds is known, this review article focuses on the bioactive substances with scientifically-proven benefits for ocular tissues.

Um novo conceito para um antigo instrumento: espátula corneana flexível

Os autores descrevem um novo metodo para produzir um instrumento para colheita de material de cornea. Tal instrumento pode ser manufaturado com uma cânula ou agulha fina. O material e moldado de forma plana com o auxilio de um laminador, ou de um martelo e placa de metal. Lixa fina e utilizada para arredondar as bordas e a ponta e ligeiramente dobrada. Um cabo pode ser adicionado de modo a facilitar a manipulacao do instrumento, que pode ser reutilizado apos lavagem e esterilizacao local na ponta do metal, ou por oxido de etileno.