Novel nanostructured lipid carrier-based inserts for controlled ocular drug delivery: evaluation of corneal bioavailability and treatment efficacy in bacterial keratitis.

OBJECTIVES: The aim of the present study was to develop novel ofloxacin (OFX)-loaded nanostructured lipid carrier (NLC)-based inserts for ocular application for treatment of bacterial keratitis. METHODS: NLC loaded with 0.3% OFX was prepared by means of high shear homogenization and 0.75% chitosan oligosaccharide lactate (COL) was added. Glycerin or PEG 400 at the range of 1 - 15% was added to NLCs as plasticizers and inserts were developed by solvent casting evaporation. Characterization, in vitro release, microbiological, ex vivo and in vivo studies were performed. RESULTS: The inserts developed with the addition of glycerin (Ins3OFX) was found as optimal. The kinetic studies revealed that the release of Ins3OFX was a combination of diffusion and swelling. Ins3OFX was more bioadhesive in texture profile analysis studies. In the in vivo studies performed with rabbits, the pre-ocular retention time was enhanced up to 24 h and Cmax was increased almost six times in comparison with commercial. The rabbits were infected with Staphylococcus aureus and keratitis was confirmed. This group was treated with Ins3OFX and they recovered in 7 days with no significant sign of conjunctival redness and corneal opacity. CONCLUSION: NLC-based inserts developed with COL and glycerin may be offered as appropriate vehicles for ocular delivery.

Strabismus in infants following congenital cataract surgery.

PURPOSE: This study aimed to determine the incidence and characteristics of strabismus following congenital cataract surgery in infants. MATERIALS AND METHODS: Patients aged <12 months who underwent surgery for congenital cataract and were followed-up for ≥1 years were included. Patients that had strabismus prior to surgery were excluded. Data regarding gender, cataract laterality, morphology, and density, age at the time of cataract surgery, ocular motility post surgery, and the presence of nystagmus were retrospectively obtained from the patients' records. RESULTS: The study included 79 patients (48 male and 31 female). Unilateral surgery was performed in 14 of the patients, versus bilateral surgery in 65. Strabismus did not occur post surgery in 32 (40.5 %) of the patients (group 1), whereas 47 (59.5 %) (group 2) developed strabismus following surgery. The patients in group 1 were followed-up for a mean 50.7 ± 38.5 months, versus 50.3 ± 39 months in group 2. Mean age at the time of cataract surgery in groups 1 and 2 was 3.6 ± 1.9 years and 4.6 ± 3.2 months respectively. Mean duration of time between cataract surgery and the development of strabismus was 13.3 ± 13 months (range: 1-60 months). Unilateral cases were more prone to develop strabismus, which was statistically significant (p = 0.028). Age at the time of cataract surgery, gender, cataract density, the occurrence of aphakic glaucoma, the presence of nystagmus, and additional ocular surgery were not significantly associated with the development of strabismus. CONCLUSION: Strabismus develops more frequently in children undergoing cataract surgery. In the present study strabismus occurred in more of the patients that underwent unilateral surgery. Based on the present findings, we think that long-term careful follow-up to monitor the development of strabismus is required in all infants undergoing cataract surgery, especially unilateral cases.

Preparation and in vitro-in vivo evaluation of ofloxacin loaded ophthalmic nano structured lipid carriers modified with chitosan oligosaccharide lactate for the treatment of bacterial keratitis.

The objective of this study was to explore the potential of the nanostructured lipid carriers (NLCs) modified with chitosan oligosaccharide lactate (COL) for topical ocular application. Ofloxacin (OFX) loaded NLCs were prepared by microemulsion or high shear homogenization methods. For combination of NLCs Compritol HD5 ATO was used as solid lipid, oleic acid as liquid lipid, Tween 80 as surfactant, ethanol as co-surfactant. The optimum NLCs was modified with 0.75% COL. The properties of NLCs in the absence or presence of OFX (0.3%) were characterized as zeta potential, particle size, viscosity and pH, TEM, drug loading, encapsulation efficiency and anti-microbial properties. Ex-vivo penetration/permeation studies were performed with rabbit cornea in Franz-diffusion cells. The penetration rate of OFX from NM-COL4OFX and NH-COL4OFX were significantly higher than commercial solution. Based on the selected formulations, in vivo tests were carried out by eye-drop instillation of NLCs in rabbit. The addition of COL improved the preocular residence time, controlled the drug release and enhanced the corneal bioavailability. In conclusion, OFX COL modified NLCs prepared by high shear homogenization method could be offered as a promising strategy for ocular drug delivery.