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1.
J Pediatr Ophthalmol Strabismus ; 59(1): 53-59, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34592868

RESUMO

PURPOSE: To establish whether clinical factors were correlated with deviation control in intermittent exotropia. METHODS: This retrospective study included 54 patients with intermittent exotropia. The patient's sex, family history, age at first admission, best corrected visual acuity, refractive errors after cycloplegia, angles of ocular deviation at near and distance, and near, distance, and total deviation control were evaluated. Ocular deviation controls were determined according to the Mayo Clinic's office-based scale. Correlation analysis was performed between the deviation control and the determined clinical factors. RESULTS: Spearman correlation analyses revealed a mild correlation between age with total exotropia control score and age with the control of near exotropia control score (r = 0.320, P = .018 and r = 0.339, P = .012, respectively). The angle of deviation at near showed a significant moderate correlation between total exotropia control score and near exotropia control score (r = 0.523, P < .001 and r = 0.780, P < .001, respectively). The deviation angle at distance showed a mild correlation with distance exotropia control score and total exotropia control score (r = 0.423, P = .001 and r = 0.288, P = .034, respectively). The angle of deviation at distance showed a mild correlation with the angle of deviation at near (r = 0.359, P = .008). The deviation angle at distance was established as an independent factor for predicting total exotropia score (P = .037, P = .015, respectively). CONCLUSIONS: The high deviation angle correlates positively with poor deviation control. The distance deviation angle is an independent predictor of total deviation control for the first time in the literature. [J Pediatr Ophthalmol Strabismus. 2022;59(1):53-59.].


Assuntos
Exotropia , Doença Crônica , Exotropia/diagnóstico , Olho , Humanos , Estudos Retrospectivos , Acuidade Visual
2.
J Control Release ; 324: 238-249, 2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32413453

RESUMO

AIM: Keratoconus is a common and progressive eye disease characterized by thinning and tapering of the cornea. This degenerative eye disease is currently treated in the clinic with an interventional technique ("epi-off") that can cause serious side effects as a result of the surgical procedure. The aim of this project is to design innovative formulations for the development of a riboflavin-containing medicinal product to develop a non-invasive ("epi-on") keratoconus treatment as an alternative to current treatment modalities. METHODS: Nanostructured lipid carriers (NLCs) were successfully loaded with either riboflavin base of riboflavin-5-phosphate sodium and designed with either Stearylamine (positive charge) or Trancutol P (permeation enhancer). In vitro characterization studies, cytotoxicity and permeability studies were performed. Selected formulations and commercial preparations were applied and compared in ex-vivo corneal drug accumulation and transition studies. Furthermore, in vivo studies were performed to assess drug accumulation in the rat cornea and the corneal stability after NLC treatment was investigated via a biomechanical study on isolated rabbit corneas. RESULTS: Both in vitro and ex-vivo as well as in vivo data showed that from the prepared NLC formulations, the most effective formulation was riboflavin-5-phosphate sodium containing NLC with Transcutol P as permeation enhancer. It possessed the highest drug loading content, low accumulation in the cornea but high permeability through the cornea as well as the highest functional performance in corneal crosslinking. CONCLUSION: Topical application of riboflavin-5-phosphate sodium loaded NLC systems designed with permeation enhancer Transcutol P may act as a potential alternative for non-invasive keratoconus treatments.


Assuntos
Ceratocone , Riboflavina/administração & dosagem , Animais , Córnea , Sistemas de Liberação de Medicamentos , Ceratocone/tratamento farmacológico , Lipídeos , Fármacos Fotossensibilizantes , Coelhos , Ratos , Raios Ultravioleta
3.
Ophthalmic Surg Lasers Imaging Retina ; 50(7): 437-443, 2019 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-31344243

RESUMO

BACKGROUND AND OBJECTIVE: To evaluate changes in retrobulbar blood flow by using color Doppler ultrasonography (CDUS) after intravitreal ranibizumab injection in patients with neovascular age-related macular degeneration (AMD). PATIENTS AND METHODS: Eighteen patients who had undergone intravitreal ranibizumab (0.05 mg/0.05 mL) injection due to choroidal neovascular membrane (CNVM) were included in the study. Contralateral eyes of the patients were also analyzed. Peak systolic velocity (PSV), end diastolic velocity (EDV), pulsatility index (PI), and resistivity index (RI) were measured from the ophthalmic artery (OA), central retinal artery (CRA), lateral posterior ciliary artery (LPCA), and medial posterior ciliary artery (MPCA) for all patients pre-injection, and at 1 day, 1 week, and 1 month after ranibizumab injection. RESULTS: The mean age of the 18 patients included in the study was 66.94 years (± 8.3 years). Of these 18 patients, eight were female and 10 were male. After Bonferroni's correction for multiple comparisons was carried out, there were significant differences only in some values of LPCA; these included the decrease in EDV and an increase in PI values of LPCA between the pre-injection and post-injection of the first month measurements in uninjected eyes (P = .002, P = .002), and a decrease in PI value of LPCA between post-injection first day and first week measurements in injected eyes (P = .004). There were no statistically significant differences in other parameters. CONCLUSION: Ocular blood flow velocities may change after intravitreal ranibizumab injection in patients with CNVM. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:437-443.].


Assuntos
Inibidores da Angiogênese/uso terapêutico , Neovascularização de Coroide/tratamento farmacológico , Ranibizumab/uso terapêutico , Degeneração Macular Exsudativa/tratamento farmacológico , Idoso , Velocidade do Fluxo Sanguíneo/fisiologia , Neovascularização de Coroide/fisiopatologia , Feminino , Hemodinâmica/fisiologia , Humanos , Injeções Intravítreas , Masculino , Pessoa de Meia-Idade , Órbita/irrigação sanguínea , Degeneração Macular Exsudativa/fisiopatologia
4.
J Biomed Nanotechnol ; 15(4): 830-838, 2019 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-30841975

RESUMO

Purpose: The aim of this study was to synthesize bevacizumab-loaded nanoparticles and evaluate their effects on the treatment of posterior segment diseases via subtenon injections. Methods: Bevacizumab-loaded chitosan nanoparticles (BLCNs) were synthesized by the ionic gelation method, and their physicochemical characteristics and in vitro release profile were studied. The BLCNs were characterized using atomic force microscopy (AFM), FTIR spectroscopy, dynamic light scattering, and scanning electron microscopy. The BLCNs were delivered into rabbits' eyes via posterior subtenon injections. An immunohistochemical evaluation of the ocular tissues was performed, and the vitreous humor and serum bevacizumab levels were measured by ELISA. Results: Bevacizumab-loaded chitosan nanoparticles with a diameter of 80 to 380 nm were prepared and characterized. In vitro studies showed that after the first 5 days of the experiment, a significant increase in the drug release maintained the desired drug dosage for 3 weeks. Immunohistochemical in vivo studies revealed that there were BLCNs penetrating through the sclera. Furthermore, the intravitreal bevacizumab concentration reached a maximum concentration of 18 µg/ml, and it decreased to 6 µg/ml after only a week. Conclusion: The results revealed that subtenon injection of BLCNs is a promising alternative to intravitreal injections. In addition to the ELISA studies, immunohistochemical experiments confirmed that BLCNs enable transscleral bevacizumab penetration, and BLCN usage may provide the required bevacizumab levels for the treatment of posterior segment diseases.


Assuntos
Nanopartículas , Animais , Bevacizumab , Quitosana , Coelhos , Esclera , Corpo Vítreo
5.
Int Ophthalmol ; 38(5): 1851-1861, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28852905

RESUMO

PURPOSE: To determine and quantify the risk factors for disruption of lens capsule integrity during phacoemulsification. METHODS: The medical records of the patients who had undergone phacoemulsification cataract surgery and had a complication associated with lens capsule were reviewed. Consecutive cases were also reviewed in reverse chronological order as a control group. The exclusion criteria were pediatric cataracts, traumatic cataracts and lens dislocation. As a result, 403 uncomplicated and 83 complicated eyes were analyzed. The differences between the complication group and the group without complications regarding the risk factors were shown by employing the Chi-square test and Fischer's exact test. The variables having the level of significance (p < 0.25) after the Chi-square test and Fischer's exact test were enrolled into the multiple stepwise logistic regression analysis. RESULTS: Age (60-69/≤80) (p = 0.017), male gender (p = 0.006), pupil size ≤3 mm (p = <0.001), mature-brunescent cataract (p = <0.001), anterior chamber depth <2.5 mm (p = 0.001), posterior polar cataract (p = 0.006), diabetic retinopathy(p = <0.001), coronary artery disease (p = 0.098) and surgeon factor (junior resident/senior resident, p = 0.015; senior resident/specialist in ophthalmology, p = 0.026; junior resident/specialist in ophthalmology, p = 0.020) were among the factors significantly related to a capsule complication. An Excel program has been developed according to these results to predict the probability of capsule complication. CONCLUSIONS: Higher-risk cases can be predicted preoperatively, thus allowing surgeons to take appropriate precautions, better informing the patient and better selecting the cases especially for trainee surgeons.


Assuntos
Facoemulsificação/efeitos adversos , Ruptura da Cápsula Posterior do Olho/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Medição de Risco/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Ruptura da Cápsula Posterior do Olho/diagnóstico , Ruptura da Cápsula Posterior do Olho/etiologia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/etiologia , Fatores de Risco , Ruptura , Turquia/epidemiologia
6.
Comput Biol Med ; 87: 152-161, 2017 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-28595130

RESUMO

BACKGROUND AND OBJECTIVES: Measurements of the cyclotorsional movement of the eye are crucial in refractive surgery procedures. The planned surgery pattern may vary substantially during an operation because of the position and eye movements of the patient. Since these factors affect the outcome of an operation, eye registration methods are applied in order to compensate for errors. While the majority of applications are based on features of the iris, we propose a registration method which uses scleral blood vessels. Unlike previous offline techniques, the proposed method is applicable during surgery. METHODS: The sensitivity of the proposed registration method is tested on an artificial benchmark dataset involving five eye models and 46,305 instances of eye images. The cyclotorsion angles of the dataset vary between -10° and +10° at 1° intervals. Repeated measurements and ANOVA and Cochran's Q tests are applied in order to determine the significance of the proposed method. Additionally, a pilot study is carried out using data obtained from a commercially available device. The real data are validated using manual marking by an expert. RESULTS AND CONCLUSIONS: The results confirm that the proposed method produces a smaller error rate (mean = 0.44 ± 0.41) compared to the existing method in [1] (mean = 0.64 ± 0.58). A further conclusion is that feature extraction algorithms affect the results of the proposed method. The SIFT (mean = 0.74 ± 0.78), SURF64 (mean = 0.56 ± 0.46), SURF128 (mean = 0.57 ± 0.48) and ASIFT (mean = 0.29 ± 0.25) feature extraction algorithms were examined; the ASIFT method was the most successful of these algorithms. Scleral blood vessels are observed to be useful as a feature extraction region due to their textural properties.


Assuntos
Vasos Sanguíneos/fisiologia , Esclera/irrigação sanguínea , Algoritmos , Humanos , Ceratomileuse Assistida por Excimer Laser In Situ
7.
Turk J Med Sci ; 47(1): 40-46, 2017 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-28263518

RESUMO

BACKGROUND/AIM: To evaluate the effect of intravitreal pro re nata (PRN) ranibizumab treatment from the start on the best-corrected visual acuity (BCVA) and the central retinal thickness (CRT) in macular edema (ME) due to branch retinal vein occlusion (BRVO). MATERIALS AND METHODS: Patients with ME secondary to BRVO, who were treated on a PRN basis after a single intravitreal ranibizumab injection, were retrospectively evaluated. The main outcome measures were changes in BCVA and CRT as measured by optical coherence tomography. RESULTS: The number of injections over 6 months was 2.43 ± 1.16. The mean BCVA of the patients was 0.84 ± 0.10 logMAR at baseline and 0.41 ± 0.06 at the 6th month (P < 0.001). Mean BCVA of the ischemic BRVO group was 1.06 ± 0.68 logMAR at baseline and 0.44 ± 0.30 logMAR at the 6th month (P < 0.05). Similarly, the mean BCVA of the nonischemic BRVO group was 0.77 ± 0.53 logMAR at baseline and 0.41 ± 0.36 logMAR at the 6th month (P < 0.05). Between groups, there was no significant difference in mean BCVA at any examination. CONCLUSION: Intravitreal ranibizumab is a safe and effective treatment option for ME due to ischemic and nonischemic BRVO using PRN from the start.


Assuntos
Inibidores da Angiogênese/uso terapêutico , Edema Macular/tratamento farmacológico , Ranibizumab/uso terapêutico , Oclusão da Veia Retiniana/complicações , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/administração & dosagem , Feminino , Humanos , Injeções Intravítreas , Edema Macular/etiologia , Masculino , Pessoa de Meia-Idade , Ranibizumab/administração & dosagem , Estudos Retrospectivos , Acuidade Visual
8.
Ophthalmic Surg Lasers Imaging Retina ; 48(1): 10-17, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28060389

RESUMO

BACKGROUND AND OBJECTIVE: To evaluate the effects of obesity on choroidal thickness (CT) in childhood. PATIENTS AND METHODS: Forty-four patients with obesity (study group) and 42 healthy children (control group) were enrolled in the study. Subjects underwent a complete ocular examination. The mean CT was measured by enhanced depth imaging optical coherence tomography (EDI-OCT). Body mass index (BMI) was calculated. RESULTS: Mean BMI value was 31.8 ± 1.9 in the study group and 19.8 ± 4.4 in the control group. The mean subfoveal CT value 385.77 µm ± 6.09 µm in the study group and 348.43 µm ± 73.21 µm in the control group. There was a significant difference between the study and control groups with regard to subfoveal CT (P = .017). Subfoveal CT and BMI were positively correlated (r = 0.288; P = .004). CONCLUSIONS: CT increases in childhood obesity. Findings revealed that adiposity causes a significant increase in CT, and it may be related to ocular complications. [Ophthalmic Surg Lasers Imaging Retina. 2017;48:10-17.].


Assuntos
Doenças da Coroide/etiologia , Corioide/patologia , Obesidade Infantil/complicações , Tomografia de Coerência Óptica/métodos , Adolescente , Índice de Massa Corporal , Doenças da Coroide/diagnóstico , Estudos Transversais , Feminino , Humanos , Masculino
9.
J Ophthalmol ; 2017: 4271671, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29333291

RESUMO

BACKGROUND: To evaluate the effects of topical 0.5% ketorolac treatment combined with topical steroids on macular thickness in cases who had uneventful phacoemulsification surgery. METHODS: 58 eyes of 58 consecutive cases were included. The mean foveal thickness (MFT), parafoveal thickness (ParaFT), and perifoveal thickness (PeriFT) measurements were performed with optical coherence tomography (RTVue-100, Optovue, Fremont, CA, USA) preoperatively and at postoperative 1 week, 1 month, and 2 months. All cases received topical 0.1% dexamethasone postoperatively. Randomly selected cases additionally received topical 0.5% ketorolac, which started 2 days prior to surgery. Cases who received both topical steroids and ketorolac formed group 1 and subjects who received only topical steroids formed group 2. RESULTS: The increase in mean MFT at the 1st week, 1st month, and 2nd months after surgery in group 1 was significantly lower than group 2 (P = 0.008, P ≤ 0.001, and P ≤ 0.001, resp.). In group 1, the increase in mean ParaFT and PeriFT was significantly lower than group 2 at the 1st and 2nd months of the surgery (P < 0.05 for all variables). CONCLUSIONS: Topical ketorolac combined with steroids is highly efficacious in order to prevent increment in thickness on each part of the macula even after an uneventful phacoemulsification surgery comparing to steroid monotheraphy.

10.
Semin Ophthalmol ; 32(4): 474-481, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27078188

RESUMO

PURPOSE: To investigate and compare the long-term safety, efficacy, and accuracy of PRK (photorefractive keratectomy) and LASEK (laser epithelial keratomileusis) in myopic corneas having residual corneal thickness less than 400 micron meters (µm). METHODS: The medical reports of the patients who had undergone excimer laser surface ablation between 2007-2011 and had a residual corneal thickness less than 400 µm were retrospectively reviewed. RESULTS: Forty-two eyes of 42 patients with a mean age of 28.79±7.76 years were enrolled into the study. Twenty-two PRK and 20 LASEK procedures were performed. The mean follow-up time was 45.00±11.80 months. At the end of follow-up, no ectasia was detected. Nineteen percent of eyes had trace haze. No eyes lost any lines in corrected distance visual acuity. Eighty-one percent of the patients had an uncorrected distance visual acuity better than 20/40. The regression rate was 16.7%. Sixty-two percent of eyes were within ±1.00 D. The safety and efficacy indexes were 1.19±0.42 and 1.00±0.40, respectively. There was not any difference between LASEK and PRK regarding achieved spherical equivalent refraction, haze ratio, visual acuity, safety, efficacy, and regression. CONCLUSIONS: Both PRK and LASEK are safe and effective in myopic corneas having thin residual thickness.


Assuntos
Córnea/patologia , Ceratomileuse Assistida por Excimer Laser In Situ/métodos , Lasers de Excimer/uso terapêutico , Miopia/cirurgia , Ceratectomia Fotorrefrativa/métodos , Complicações Pós-Operatórias , Acuidade Visual , Adulto , Córnea/cirurgia , Paquimetria Corneana , Feminino , Seguimentos , Humanos , Masculino , Miopia/fisiopatologia , Refração Ocular , Estudos Retrospectivos , Fatores de Tempo
11.
J Ophthalmol ; 2016: 1965720, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27747098

RESUMO

Purpose. To investigate the effect of platelet-rich fibrin (PRF) membrane on wound healing. Methods. Twenty-four right eyes of 24 New Zealand rabbits equally divided into 2 groups for the study design. After the creation of 5 × 5 mm conjunctival damage, it was secured with PRF membrane, which was generated from the rabbit's whole blood samples in PRF membrane group, whereas damage was left unsutured in the control group. Three animals were sacrificed in each group on the 1st, 3rd, 7th, and 28th postoperative days. Immunohistochemical (IHC) stainings and biomicroscopic evaluation were performed and compared between groups. Results. PRF membrane generated significant expressions of vascular endothelial growth factor (VEGF), transforming growth factor-beta (TGF-ß), and platelet-derived growth factor (PDGF) in the early postoperative period. However, the IHC evaluation allowed showing the excessive staining at day 28, in control group. Biomicroscopic evaluation revealed complete epithelialization in PRF membrane group, but none of the cases showed complete healing in the control group. Conclusions. This experimental study showed us the beneficial effects of the PRF membrane on conjunctival healing. Besides its chemical effects, it provides mechanical support as a scaffold for the migrating cells that are important for ocular surface regeneration. These overall results encourage us to apply autologous PRF membrane as a growth factor-enriched endogenous scaffold for ocular surface reconstruction.

12.
Cornea ; 35(12): 1503-1507, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27741013

RESUMO

PURPOSE: To assess the preoperative patient characteristics that may predict outcomes of keratoconus 2 years after corneal collagen cross-linking (CXL) in pediatric patients with keratoconus. METHODS: This retrospective study included 72 eyes of 52 consecutive patients with keratoconus under the age of 18 with 2-year follow-up after CXL. Subgroup analysis and cutoff values were determined as per age (<14 and ≥14 years), sex, baseline uncorrected and corrected distance visual acuities (UCVA, CDVA; <0.8 and ≥0.8 logMAR), topographic cone location (central and paracentral), maximum keratometry (K-max, <54 and ≥54 diopters), and corneal thickness at the thinnest point (thCT) (<450 and ≥450 µm) to evaluate the associations between preoperative patient characteristics and outcomes of CXL treatment in terms of K-max. Postoperative progression in K-max was defined as steepening of 1.0 diopter or more. RESULTS: Average age of patients was 14.8 ± 2.2 (9-17) years. After 2 years, the mean UCVA significantly improved and the mean thCT significantly decreased in all patients (P = 0.023, P < 0.001, respectively). The K-max in patients with paracentral cones and/or with thCT less than 450 µm were more likely to progress (cone location: P = 0.023, odds ratio = 3.21, 95% confidence interval, 1.17-8.72; thCT: P = 0.008, odds ratio = 4.54, 95% confidence interval, 1.46-14.14). Age, sex, baseline UCVA, CDVA, and K-max did not present any significant effect on progression of CXL after treatment (P > 0.05 for all variables). CONCLUSIONS: In pediatric patients with keratoconus, cone location and the baseline thinnest corneal thickness seem to affect the success rate of CXL treatment after 2-year follow-up.


Assuntos
Colágeno/metabolismo , Substância Própria/metabolismo , Reagentes de Ligações Cruzadas , Ceratocone/diagnóstico , Ceratocone/tratamento farmacológico , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/uso terapêutico , Adolescente , Criança , Topografia da Córnea , Progressão da Doença , Feminino , Seguimentos , Humanos , Ceratocone/metabolismo , Ceratocone/fisiopatologia , Masculino , Complicações Pós-Operatórias , Estudos Retrospectivos , Riboflavina/uso terapêutico , Fatores de Risco , Raios Ultravioleta , Acuidade Visual/fisiologia
13.
14.
Cornea ; 35(9): 1245-9, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27362878

RESUMO

PURPOSE: To report the clinical and histopathological results of a novel autologous scaffold grafting, platelet-rich fibrin (PRF) membrane, in cases with descemetocele. METHODS: Three patients with severe corneal stromal melting and central descemetocele caused by neurotrophic keratopathy and infective keratitis underwent PRF membrane grafting on the central cornea for the prevention of imminent corneal perforation. After a quiescent 3-month period, penetrating keratoplasty and cataract extraction were performed for visual rehabilitation in 1 patient and host corneal tissue was examined histopathologically. RESULTS: Pain was significantly relieved, conjunctival inflammation was markedly resolved, and the central descemetocele area became thicker with scar formation in all patients. Histopathological examination revealed fibrosis formation over the descemetocele area without any tissue gap. Newly formed tissue containing irregular corneal lamellae covered the fibrosis formation and accounted for the prevention of perforation. CONCLUSIONS: Temporary PRF membrane grafting may be an alternative intervention to avoid impending corneal perforation in cases with severe descemetocele.


Assuntos
Perfuração da Córnea/cirurgia , Lâmina Limitante Posterior/patologia , Fibrina/uso terapêutico , Membranas Artificiais , Plasma Rico em Plaquetas , Idoso , Perfuração da Córnea/prevenção & controle , Humanos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias , Estudos Retrospectivos , Alicerces Teciduais , Acuidade Visual
15.
Drug Deliv ; 23(9): 3279-3284, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27027148

RESUMO

Biodegradable implants are promising drug delivery systems for sustained release ocular drug delivery with the benefits such as minimum systemic side effects, constant drug concentration at the target site and getting cleared without surgical removal. Dry eye syndrome (DES) is a common disease characterized with the changes in ocular epithelia surface and results in inflammatory reaction that might lead to blindness. Cyclosporin A (CsA) is a cyclic peptide that is frequently employed for the treatment of DES and it needs to be applied several times a day in tear drops form. The aim of this study was to evaluate in vivo behavior and efficacy of the developed nano-decorated subconjunctival implant systems for sustained release CsA delivery. Biodegradable Poly-ɛ-caprolactone (PCL) implant or micro-fiber implants containing CsA loaded poly-lactide-co-glycolide (85:15) (PLGA) or PCL nanoparticles were prepared in order to achieve sustained release. Two of the formulations PCL-PLGA-NP-F and PCL-PCL-NP-I were selected for in vivo evaluation based on their in vitro characteristics determined in our previous study. In this study, formulations were implanted to Swiss Albino mice with induced dry eye syndrome to investigate the ocular distribution of CsA following subconjunctival implantation and to evaluate the efficacy. Tissue distribution study indicated that CsA was present in ocular tissues such as cornea, sclera and lens even 90 days after the application and blood CsA levels were found lower than ocular tissues. Efficacy studies also showed that application of CsA-loaded fiber implant formulation resulted in faster recovery based on their staining scores.


Assuntos
Córnea/metabolismo , Ciclosporina/administração & dosagem , Ciclosporina/metabolismo , Nanopartículas/administração & dosagem , Implantes Absorvíveis , Animais , Química Farmacêutica/métodos , Ciclosporina/química , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/química , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Ácido Láctico/química , Masculino , Camundongos , Nanopartículas/química , Ácido Poliglicólico/química , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Distribuição Tecidual
16.
Int Ophthalmol ; 36(4): 531-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26644130

RESUMO

To investigate the efficacy of single-dose intravitreal dexamethasone implantation in the treatment of persistent diabetic macular edema (DME) unresponsive to 3 consecutive ranibizumab injections over a period of 6 months. Forty-one patients with a previous history of treatment for DME including at least three consecutive intravitreal ranibizumab injections were enrolled in this retrospective study. Main outcome measures were change in best-corrected visual acuity (BCVA), central macular thickness (CMT), and intraocular pressure from baseline to 6th month. At the baseline, the mean CMT was 572.4 ± 123.1 µm which improved to 264.2 ± 114.4, 317.7 ± 141.7, 410.6 ± 169.1, and 382.8 ± 181.5 µm at the 1st, 3rd, 5th, and 6th month, respectively (p < 0.05). The preoperative mean BCVA was 0.85 ± 0.54 logMAR units which improved to 0.76 ± 0.5 (p = 0.08), 0.69 ± 0.4 (p = 0.02), 0.74 ± 0.4 (p = 0.284), and 0.72 ± 0.3 (p = 0.489) logMAR units at the 1st, 3rd, 5th, and 6th months, respectively. Additional injections were required for 13 (31 %) eyes at 3rd month and 14 (34 %) eyes at 5th month due to recurrence of macular edema. Intravitreal dexamethasone implantation caused a significant improvement of BCVA and reduction of CMT in the patients with persistent DME that were unresponsive to 3 consecutive ranibizumab injections. However, retreatment before 6 months in the majority of the patients was needed despite the beneficial effects after the index procedure.


Assuntos
Dexametasona/administração & dosagem , Retinopatia Diabética/tratamento farmacológico , Glucocorticoides/administração & dosagem , Edema Macular/tratamento farmacológico , Idoso , Diabetes Mellitus Tipo 2/complicações , Retinopatia Diabética/diagnóstico , Implantes de Medicamento , Feminino , Angiofluoresceinografia , Humanos , Pressão Intraocular/efeitos dos fármacos , Injeções Intravítreas , Edema Macular/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia de Coerência Óptica , Resultado do Tratamento , Acuidade Visual/efeitos dos fármacos
17.
Semin Ophthalmol ; 31(3): 203-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-24840348

RESUMO

PURPOSE: The aim of this study was to investigate the sensitivity, specificity, and accuracy of The Cone Location and Magnitude Index (CLMI) in keratoconus diagnosis. METHODS: 301 eyes of 159 keratoconus patients and 394 eyes of 265 refractive surgery candidates as a control group were enrolled in this retrospective clinical study. CLMI was compared with keratometric corneal topography parameters, wavefront aberrations, and pachymetry data derived from optical coherence tomography using independent sample t-tests and ROC curves. Logistic regression analysis was applied to determine the most accurate parameter in keratoconus diagnosis. Pearson's correlation analysis was used to determine the correlation between CLMI and the other measurements. RESULTS: Average axial CLMI (aCLMI) was 8.19 ± 6.15 D in the keratoconus group and 0.83 ± 0.62 D in the control group (p = 0.001). aCLMI had the greatest sensitivity (89%), specificity (94%), and accuracy (92%) for the keratoconus diagnosis at the best cut-off point of 1.82 according to the ROC curve. Logistic regression analysis selected aCLMI as the most accurate measurement among the other parameters (accuracy 92.8%). aCLMI showed strongest correlations with coma-like aberrations (r = 0.881), total high-order aberrations (r = 0.858), and vertical coma (r = -0.814), respectively. CONCLUSION: CLMI is a robust index for screening keratoconus with high sensitivity, specificity, and accuracy.


Assuntos
Córnea/patologia , Ceratocone/diagnóstico , Adulto , Paquimetria Corneana , Topografia da Córnea , Aberrações de Frente de Onda da Córnea/diagnóstico , Dilatação Patológica/diagnóstico , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia de Coerência Óptica , Adulto Jovem
18.
J Cataract Refract Surg ; 41(8): 1730-7, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26432132

RESUMO

PURPOSE: To compare the complications occurring within the first 3 months of corneal collagen crosslinking (CXL) performed with mechanical or transepithelial phototherapeutic keratectomy (PTK) epithelial removal in keratoconus patients. SETTING: Yildirim Beyazit University Ataturk Training and Research Hospital, Ankara, Turkey. DESIGN: Nonrandomized retrospective clinical study. METHODS: Eyes of consecutive progressive keratoconus patients who had PTK or mechanical epithelial removal followed by CXL were included. All patients were examined regularly until epithelial healing. Detailed ophthalmologic examinations were performed preoperatively and 1 and 3 months postoperatively. RESULTS: The study comprised 499 eyes (302 patients) that had transepithelial PTK (Group 1, 153 eyes) or mechanical epithelial removal (Group 2, 256 eyes) followed by CXL. Delayed epithelial healing occurred in 15.0% of eyes in Group 1 and 3.5% of eyes in Group 2 (P = .001). Epithelial hypertrophy occurred in 24.8% of eyes and 3.5% of eyes, respectively (P = .001). Salzmann-like epithelial nodules (2.6%), epithelial herpetic keratitis (1.9%), anterior uveitis (1.9%), and elevated intraocular pressure (1.9%) occurred in Group 1 only and infective keratitis (0.8%) in Group 2 only. Marked stromal edema and peripheral sterile infiltrates occurred at similar rates in both groups (P = .567 and P = .479, respectively). Grade 1+ corneal haze was significantly high in Group 2. Grade 2+ and 3+ haze was significantly high in Group 1 (P = .001). CONCLUSIONS: Ocular surface healing disorders were the most common early complications of CXL. Short-term complications were higher with the transepithelial PTK epithelial removal technique than with mechanical epithelial removal. FINANCIAL DISCLOSURE: No author has a financial or proprietary interest in any material or method mentioned.


Assuntos
Colágeno/metabolismo , Substância Própria/metabolismo , Reagentes de Ligações Cruzadas , Desbridamento/métodos , Epitélio Corneano/cirurgia , Ceratocone/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Adolescente , Adulto , Criança , Topografia da Córnea , Feminino , Seguimentos , Humanos , Ceratocone/metabolismo , Ceratocone/fisiopatologia , Masculino , Complicações Pós-Operatórias , Estudos Retrospectivos , Riboflavina/uso terapêutico , Raios Ultravioleta , Acuidade Visual/fisiologia , Adulto Jovem
19.
Eye Contact Lens ; 41(6): 382-5, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25839346

RESUMO

PURPOSE: To investigate the variations in biomechanical properties of the cornea in rheumatoid arthritis (RA) patients. METHODS: A total of 53 RA patients, and 25 healthy individuals (control group) were enrolled. Rheumatoid arthritis patients were classified as in active phase (group 1; n=24) or in remission phase (group 2; n=29). Corneal biomechanical parameters including corneal hysteresis (CH), corneal resistance factor (CRF), corneal compensated intraocular pressure (IOPcc), and Goldmann-correlated IOP (IOPg) were measured with the Reichert Ocular Response Analyzer. Topographical measurements, including central corneal thickness (CCT), anterior chamber depth, iridocorneal angle, and corneal volume were measured using a Sirius corneal topographer. RESULTS: The mean CH was 9.43±1.17 mm Hg in group 1, 9.42±1.84 mm Hg in group 2, and 10.47±1.68 mm Hg in the control group (P=0.03). The mean IOPcc was 17.85±3.2 mm Hg in group 1, 17.95±3.49 mm Hg in group 2, and 15.36±3.11 mm Hg in the control group (P=0.008). The CH showed a significant positive correlation with CRF (P=0.000, r=0.809) and CCT (P=0.000, r=0.461), and a significant negative correlation with IOPcc (P=0.000, r=-0.469). CONCLUSIONS: Decrease in the mean CH measurements indicates that ultrastructural changes in the cornea may occur in the active phase, and these changes persist in the remission period. In addition, IOPcc is significantly affected by the corneal biomechanical properties. In RA patients, it is important to control the corneal parameters and IOP measurements against the irreversible changes on the optic nerve.


Assuntos
Artrite Reumatoide/fisiopatologia , Córnea/fisiopatologia , Adulto , Idoso , Análise de Variância , Fenômenos Biomecânicos , Estudos de Casos e Controles , Topografia da Córnea , Estudos Transversais , Feminino , Humanos , Pressão Intraocular , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Tonometria Ocular , Adulto Jovem
20.
J Pharm Sci ; 104(5): 1709-20, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25716582

RESUMO

In terms of ocular drug delivery, biodegradable implant systems have several advantages including the ability to provide constant drug concentration at the target site, no necessity for surgical removal, and minimum systemic side effects. Cyclosporin A (CsA) is a neutral, hydrophobic, cyclic peptide of amino acids that frequently used for dry eye disease treatment. The aim of this study was to develop a nanoparticle-loaded implant system for sustained-release CsA delivery following subconjunctival implantation. Poly(lactide-co-glycolide) (85:15) or poly-ε-caprolactone (PCL) were used to prepare two different nanoparticle formulations. These nanoparticles loaded into PCL or poly(lactide-co-caprolactone) implant formulations were prepared by two different methods, which were molding and electrospinning. Size and zeta potential of nanoparticles were determined and the morphology of the formulations were investigated by scanning electron microscopy. CsA-loading efficiencies were calculated and the in vitro degradation and in vitro release studies were performed. MTT test was also performed using L929 fibroblast cells to evaluate the cytotoxicity of the formulations. PCL-PCL-NP-I formulation was implanted to Swiss Albino mice with induced dry eye syndrome to evaluate the efficacy. In vitro release studies showed that the release from the formulations continues between 30 and 60 days, and the cell viability was found to be 77.4%-99.0%. In vivo studies showed that healing is significantly faster in the presence of the selected implant formulation. Results indicated that nanodecorated implants are promising ocular carriers for controlled-release CsA application.


Assuntos
Túnica Conjuntiva/efeitos dos fármacos , Ciclosporina/síntese química , Implantes de Medicamento/síntese química , Nanopartículas/química , Animais , Ciclosporina/administração & dosagem , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/síntese química , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/síntese química , Avaliação de Medicamentos/métodos , Implantes de Medicamento/administração & dosagem , Masculino , Camundongos , Nanopartículas/administração & dosagem , Poliésteres/administração & dosagem , Poliésteres/síntese química
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