PURPOSE To characterize posterior corneal aberrations in keratoconic (KC) eyes and investigate compensatory effects between anterior and posterior corneal surfaces. METHODS The corneal topography of 113 eyes (37 advanced KC, 31 moderate KC, 14 mild KC, and 31 normal eyes) was used to compute the corneal aberrations. The central 6-mm diameter of both anterior and posterior corneal topographies...

PURPOSE To investigate changes in corneal topography and morphology in human eyes wearing orthokeratology (OK) lenses for overnight and over a 5-year period. MATERIALS AND METHODS Fifty-six adults with moderate myopia were assigned to 2 groups based on age matching: 5-year lens wear (n = 26, 51 eyes) and 1-night lens wear (n = 30, 60 eyes). All subjects wore reverse-geometry OK lenses with th...

Three adult rhesus monkeys were subjected to 2 and 24 hours of polymethylmethacrylate (PMMA) contact lens wear. The induced corneal changes were examined with the electron microscope. Mild epithelial oedema as well as early degenerative cell changes was present already after 2 hours' wear. Rigid lens wear for 24 hours produced more severe oedema and cell alterations together with premature cell...

PURPOSE To evaluate the effect of intrastromal corneal ring implantation on corneal curvature in rabbits. METHODS Thirty eyes of 15 rabbits were divided into two groups: group 1 with 7 animals and group 2 with 8 animals. The left eye underwent surgery and the right eye was used as control. Ultrasound pachymetry and corneal topography were performed prior to surgery. Anterior segment biomicros...

purpose: to describe a case with a rare complication of posterior chamber intraocular lens (pc-iol) implantation in a patient who had undergone extracapsular cataract extraction (ecce) two years before case report: a 80-year-old diabetic woman presented with an exposed pc-iol in her left eye with a history of mechanical trauma. slit-lamp examination revealed an extruded pc-iol lied on the anter...

PURPOSE To determine the shape and astigmatism of the posterior corneal surface in a healthy population with age, using Scheimpflug photography corrected for distortion due to the geometry of the Scheimpflug imaging system and the refraction of the anterior corneal surface. METHODS Scheimpflug imaging was used to measure in six meridians the cornea of the right eye of 114 subjects, ranging in...

PURPOSE To evaluate the characteristics of the posterior corneal surface in patients with high myopia before cataract surgery. METHODS We performed a cross-sectional study at the Eye and ENT Hospital of Fudan University, Shanghai, China. Corneal astigmatism and axial length were measured with a rotating Scheimpflug camera (Pentacam) and partial coherence interferometry (IOLMaster) in a high-m...

PURPOSE To compare the anterior and posterior corneal elevation maps between keratoconus-suspect eyes and normal eyes. SETTING Rothschild Foundation, AP-HP, University Paris VII, Hôpital Bichat Claude Bernard, Paris, France. METHODS The anterior and posterior corneal surface elevations were analyzed and compared in 60 normal myopic patients and 48 keratoconus-suspect patients. The anterior ...

The article “Surgically Induced Astigmatism Assessment: Comparison Between Three Corneal Measuring Devices” by Ofir et al.1 was effective in demonstrating equivalence between three anterior corneal measuring devices (Lenstar LS900, Haag-Streit, Koeniz, Switzerland; IOLMaster 500, Carl Zeiss Meditec, Dublin, CA; and Atlas topographer, Carl Zeiss Meditec) by assessing the vectorial astigmatism ch...