in addition to graft clarity, an acceptable refractive error is essential to consider a corneal transplant successful. the most common complication of penetrating keratoplasty (pk) is postkeratoplasty astigmatism which can result in decreased visual acuity, anisometropia, and mono-ocular diplopia. these complications can cause patient dissatisfaction, in spite of a successful transplant. intrao...

Conductometric gas sensors made of gas permeable metal oxide ultrathin membranes can combine the functions of a selective filter, preconcentrator, and sensing element and thus can be particularly promising for the active sampling of diluted analytes. Here we report a case study of the electron transport and gas sensing properties of such a membrane made of nanoporous Ta₂O₅. These membranes demo...

Purpose. The purpose of this study is to evaluate the vision related quality of life in patients with keratoconus by using the National Eye Institute Visual Function Questionnaire-25 (NEI-VFQ-25). Methods. Thirty patients presented with keratoconus (keratoconus group) and 30 healthy patients (control group) were included in this study. Twenty patients were using rigid gas permeable and 10 patie...

PURPOSE To evaluate the clinical performance of Monocurve and Bicurve (Soper-McGuire design) rigid gas-permeable contact lens fitting in patients with keratoconus. METHODS A prospective and randomized comparative clinical trial was conducted with a minimum follow-up of six months in two groups of 63 patients. One group was fitted with Monocurve contact lenses and the other with Bicurve Soper-...

A prediction (Latin præ-, "before," and dicere, "to say") or forecast can be defined as “a statement about the way things will happen in the future, often but not always based on experience or knowledge. Although guaranteed information about the future is in many cases impossible, prediction is necessary to allow plans to be made about possible developments” (Wikipedia). Some predictions in the...

OBJECTIVES The aim of this review is to evaluate the ocular safety of orthokeratology (OrthoK) treatment of myopia correction and retardation. DATA SOURCES Clinical studies published in English and Chinese were identified from MEDLINE, EMBASE CNKI, CQVIP, and WANFANG DATA (all from 1980 to April 2015). The reference lists of the studies and the Science Citation Index were also searched. SEL...

PURPOSE To determine the effects on corneal epithelial permeability and ocular response of 30 nights of continuous wear (CW) of gas permeable (GP) and silicone hydrogel (SiH) contact lenses. METHODS Ninety-one subjects successfully completed 30 days of CW of either GP (n = 42) or SiH (n = 49) contact lenses. Epithelial permeability (P(dc)) was measured by scanning fluorometer at an afternoon ...

PURPOSE To evaluate the success rate of highly gas permeable scleral contact lenses (SCL) for visual rehabilitation after penetrating keratoplasty (PK), over a period of up to 9 years. METHODS A total database of 31 consecutive patient fitted with SCL between January 2004 and December 2009 was retrospectively reviewed. Demographic data, etiology prior to lens fitting, visual outcomes, follow ...

PURPOSE To evaluate changes in the concentration of tear immunoglobulins in contact lens wearers. METHODS A total of 45 cases including 23 contact lens wearers (43 eyes) and 22 age and sex matched healthy controls having no ocular pathology were studied for immunoglobulins (IgA, IgG, IgM) in their tears by single radial immunodiffusion method. RESULTS Most of the cases used soft (56.6%) and...