Development and evaluation of polycaprolactone-based electrospun nanofibers containing timolol maleate as a sustained-release device for treatment of glaucoma: in vivo evaluation in equine eye.

Background and purpose: Prolonging the drug release can be a suitable approach to overcome the challenges related to topical ophthalmic administration of drugs especially the ones prescribed for chronic ailments. The sustained delivery of the drug would reduce the required frequency of administration which could extremely improve patient compliance and feeling of well-being. This study aimed to develop nanofibrous inserts for sustained ophthalmic delivery of timolol maleate (TIM) for the treatment of glaucoma. Experimental approach: Polycaprolactone-based nanofibers containing TIM were prepared using pure polycaprolactone or a blend of it with cellulose acetate or Eudragit RL100 polymers by the electrospinning method. Following the preparation, polymeric inserts were evaluated for morphological and physicochemical properties. The in vitro drug release was assessed and the in vivo efficacy of a selected insert in decreasing the intraocular pressure (IOP) was also evaluated in the equine eyes. Findings / Results: Prepared nanofibers indicated diameter ranged between 122-174 nm. The formulations showed suitable physicochemical properties and stability for ophthalmic administration. In vitro release study showed prolonged release of drug during more than 3 days. In vivo evaluation revealed that the prepared insert is non-irritant and non-toxic to the equine eyes while having suitable efficacy in decreasing the IOP during 6 days. Conclusions and implication: Prepared TIM inserts indicated a higher efficacy than commercial TIM eye drop in lowering IOP during a prolonged period. Thus, these formulations can be considered suitable for enhancing patient compliance by reducing the frequency of administration in the treatment of glaucoma.

Studying the factors related to refractive error regression after PRK surgery.

BACKGTOUND: Photorefractive keratectomy (PRK) is used for a wide range of refractive errors such as low to moderate myopia, hyperopia and astigmatism. While many improvements have been made in laser application and accuracy as well as the modes of corneal flap removal, and although the results are somewhat predictable, regression of refractive errors is still a common complaint among the patients undergoing refractive surgery with Excimer Laser. We aimed to determine related factors of regression following photorefractive keratectomy (PRK) in different types of refractive errors. METHODS: This cross-sectional study included patients who had undergone PRK more than 6 months previously and investigated refractive error regression and related factors. The participants were those who had PRK eye surgery for the first time from 2013 to 2016 using Technolas 217z100. A refraction value of spherical equivalent > 0.75 D after cycloplegic refraction was defined as refractive error regression. RESULTS: A total of 293 eyes on 150 subjects were studied. The preoperative refractive error of the eyes were as follows: 5.5% were myopic, 1% were hyperopic, 4.8% had astigmatism, 76% had myopic astigmatism and 12.6% had hyperopic astigmatism. Regressed and non-regressed eyes were assessed using the generalized estimating equations for the probabilistic variables of demographic characteristics, topography and eye refraction. The variables of simulated keratometry astigmatism (simK) (OR = 2.8; p = 0.04), 5 mm irregularity (OR = 3.56; p = 0.01) and sphere value (OR = 1.98; p = 0.01) were significantly related to refractive error regression. There was no significant relationship between the regressed and non-regressed eyes of the same person (p ≥ 0.05). CONCLUSION: There was a positive relationship between the increase of 5 mm irregularity, simK, sphere value before surgery and refractive error regression. Age, sex and type of refraction error of the patient and the expertise of the PRK surgeon could change the general results; therefore, not all cases should be dealt with identically.

Different Nursing Care Methods for Prevention of Keratopathy Among Intensive Care Unit Patients.

BACKGROUND: Patients with reduced consciousness level suffer from eye protection disorder and Keratopathy. This study was conducted to compare effect of three eye care techniques in prevention of keratopathy in the patients hospitalized in intensive care unit of Kermanshah.   METHODS: This clinical trial was conducted in 2013 with sample size of 96 persons in three random groups. Routine care included washing of eyes with normal saline and three eye care methods were conducted with poly ethylene cover, liposic ointment, and artificial tear drop randomly on one eye of each sample and a comparison was made with the opposite eye as the control. Eyes were controlled for 5 days in terms of keratopathy. Data collection instrument was keratopathy severity index. Data statistical analysis was performed with SPSS-16 software and chi-squared test, Fisher's exact test, ANOVA and Kruskal-Wallis one-way analysis of variance. FINDINGS: The use of poly ethylene cover (0.59±0.665) was significantly more effective in prevention of keratopathy than other methods (P=0.001). There was no statistically significant difference between two care interventions of liposic ointment and artificial tear drop (P=0.844) but the results indicated the more effective liposic ointment (1.13±0.751) than the artificial tear drop (1.59±0.875) in prevention of corneal abrasion (P>0.001). CONCLUSION: Results of the study suggest the use of poly ethylene cover as a non-aggressive and non-pharmaceutical nursing and therapeutic method for prevention of keratopathy in the patient hospitalized in intensive care unit.

Keratomycosis after incidental spillage of vegetative material into the eye: Report of two cases.

Fungal corneal ulcers mostly occur after incidental corneal trauma by plant leaves in farm lands or the use of topical corticosteroids or antibiotics. The infection is more prevalent among farmers and harvesters and in some parts of the world is considered as an occupational disease; however, there have been a few reports on the occurrence of such ulcers in healthy individuals after incidental spillage of vegetative material into the eye. The importance of these ulcers is their long-term and refractory course, which makes the visual prognosis unfavorable in most patients, even after appropriate antifungal therapy or ocular interventions. Herein, we present two rare cases of fungal ulcers caused by incidental spillage of vegetative material into the eye while eating nuts and corn. We also discuss the diagnostic and therapeutic approaches, as well as visual outcome reviewing the relevant literature.

The effects of intrastromal voriconazole injection and topical voriconazole in the treatment of recalcitrant Fusarium keratitis.

PURPOSE: To describe the course and outcome in 3 patients with recalcitrant fungal keratitis treated with intrastromal voriconazole injection and topical voriconazole application. METHODS: The present study was an interventional case series. A 50 µg/0.1 mL solution of voriconazole was injected into the corneal stromal tissue around the corneal ulcer, and 1% topical voriconazole was added to the therapeutic regimen if the ulcer failed to respond to 5% topical natamycin hourly and oral ketoconazole twice per day. The infiltration and epithelial defect size were measured at each visit using a slit-lamp biomicroscope. Anatomical outcomes were assessed. RESULTS: A dramatic therapeutic response was observed in 2 patients. An amniotic membrane transplantation using cyanoacrylate glue was required to seal the microperforation in a patient with a chemical burn superinfected with Fusarium. CONCLUSIONS: Intrastromal injection of voriconazole together with topical voriconazole effectively reduced the infiltration size and controlled the infection in patients with Fusarium keratitis. However, continued application of the topical medication is critical for a favorable outcome of treatment.

"Large-bubble" modification of the "big-bubble" technique for performing maximum-depth anterior lamellar keratoplasty.

PURPOSE: To describe a new technique for performing maximum-depth anterior lamellar keratoplasty. METHODS: This was a case series study of a novel method. We combined shallow trephination of the cornea with superficial injection of air in 15 cases. This resulted in formation of a large bubble over Descemet membrane extending to the peripheral cornea. We deflated the bubble at the trephination wound and excised the button from the host completely. The follow-up was from 3 to 8 months. The best spectacle-corrected visual acuity, intraocular pressure, corneal clarity, endothelial cell count, and corneal thickness were recorded preoperatively and 3 and 6 months postoperatively. RESULTS: Successful access to intact bare Descemet membrane was obtained in all but one case, which required conversion to penetrating keratoplasty. All corneas were clear at the end of follow-up. We found a significant difference in the endothelial cell counts in the cases that we compared. The postoperative central corneal thickness increased significantly compared with preoperative levels. CONCLUSION: The early outcomes in our initial series of cases using the "large-bubble" technique suggest that it is a fast effective method.