purpose: to evaluate the safety, efficacy, stability and predictability of posterior chamber collagen copolymer phakic intraocular lens (piol) implantation to correct myopia and myopic astigmatism in keratoconus-affected patients. methods: uncorrected (ucva) and best-corrected (bcva) distance visual acuity, refraction and complications were evaluated in 22 keratoconic eyes of 14 patients who un...

purpose: to compare visual outcomes and surgical complications of three phakic intraocular lenses (piols); artisan, artiflex and the implantable collamer lens (icl) for correction of moderate to high myopia. methods: in this historical cohort study, 112 myopic eyes that were operated between 2005 and 2010 and implanted with one of these three piols were evaluated (artisan 40 eyes, artiflex 36 e...

background: silicon hydrogel bandage contact lenses are used to enhance epithelial healing, control surface-generated pain, and prevent epithelial erosions after refractive surgery. considering the importance of faster reepithelialization in preventing complications of photorefractive keratectomy (prk) and the fact that the features and specifications of these commercially-available lenses are ...

Spectral singularities of an infinite planar slab containing homogeneous optically active material at the focal plane a thin lens are investigated. The field distribution beam behind is Gaussian that we approximate by wave concentrated near optical axis lens, such its phase and amplitude distance-dependent. consequences this configuration explored determining threshold gain medium tuning resona...

Plenoptic cameras provide a robust way to capture 3D information with a single shot. This is accomplished by encoding the direction of the incoming rays with a microlens array (MLA) in front of the camera sensor. In the focused plenoptic camera, a MLA acts like multiple small cameras that capture the virtual scene on the focus plane of a main lens from slightly different angles, which enables a...

The ciliary zonules link the lens to the ciliary body in the eye, controlling the thickness of the lens for focusing through their characteristic elasticity. The ciliary zonules are composed of oxytalan fibers. Physiological or pathological damage to the ciliary zonules, including exposure to ultraviolet (UV)-A and UV-B components, can lead to lens dislocation. However, no studies have shown wh...

Raman spectroscopy is a non-invasive, non-destructive technique for the study of the macromolecular composition of tissues. Raman spectra were obtained from intact fresh and paraformaldehyde fixed rabbit lenses and from thin slices prepared from these lenses. In addition the Raman spectrum of an intact 82-yr-old human lens was compared with a slice of the same lens. It appeared that fixation wi...

The in-situ lens-bound protein layer (LBPL) was characterized on hydrogels of varying water content and ionic-binding capacity. The LBPL proved to be critically dependent on the ionic binding capacity of a given hydrogel. On nonionic polymers the LBPL invariably was thin and largely insoluble. Histochemical staining allowed the detection of all major types of tear proteins. Amino acid analysis ...