introduction: the aim of the present study was to evaluate the effect of photodynamic therapy in the treatment of experimental corneal neovascularization (nv) with benzoporphyrin derivative (bpd). methods: one group was considered as control (n=6 eyes) then, corneal nv was induced in 30 new zealand male rabbits (n=60 eyes) by placing 7.0 silk sutures at midstromal depth approximately1mm from th...

In astigmatism variations in the curvature of the cornea or lens along different meridians prevent the light rays from focusing onto a single point. Corneal refraction depends on the corneal curvature. If the cornea is more curved, the power of refraction is higher and vice versa. Corneal and lenticular astigmatism can complement or cancel each other. Their summation represents the so called “t...

Formulas For Intraocular lens Power calculatIon Modern cataract surgery replaces the natural lens of the eye with an intraocular lens (IOL). After surgery, the optical system of the eye will consist of two major refractive elements, the cornea and the newly inserted IOL. This two-lens system is at the basis of IOL power calculation. To facilitate calculations, both the cornea and the IOL are co...

PURPOSE To use optical coherence tomography (OCT) to measure corneal power and calculate intraocular lens (IOL) power in cataract surgeries after myopic and hyperopic laser vision correction (LVC). METHODS Patients with previous LVC were enrolled in this prospective study at two centers (Doheny Eye Institute, Los Angeles, CA, USA and Cullen Eye Institute, Houston, TX, USA). Corneal power was ...

Purpose: To determine the relationship between the high-frequency component of accommodative microfluctuation (HFC) and accommodative lag in presbyopic eyes and how they affect the subjective accommodation power with other ophthalmic factors, such as pupil diameter and corneal multifocality. Methods: Forty subjects (80 eyes) were included in this study, and the non-corrected distance and near v...

BACKGROUND In this study, we used a Pentacam® device to evaluate the corneal changes that occur after laser-assisted in situ keratomileusis (LASIK). METHODS Our study included 60 eyes of 32 patients. All patients were treated for myopia and myopic astigmatism using LASIK. The eyes were examined preoperatively and 3 months postoperatively using a Pentacam to assess corneal changes with regard ...

Results of intraocular lens power calculation were lower than actual required power in eyes with previous corneal refractive surgery because the inaccurate readings of corneal power obtained from standard keratometry. This causes the unacceptable hyperopia after cataract surgery. With increasing of population undergone excimer laser refractive surgery, this problem will be an obvious problem in...

BACKGROUND Presbyopic inlays have mostly been implanted under a corneal flap. Implantation in a pocket has advantages including less postoperative dry eye and neurotrophic effect, and better biomechanical corneal stability. This study investigated the effect of different pocket and flocket dimensions on corneal stability and refractive power after Raindrop™ implantation, and the associated woun...