• retina
  • We now know that this is the function of the retina, with the lens serving as a conduit of light transmission and focus to the retina. (utah.edu)
  • The lens can change shape with the aid of the ciliary muscles, thereby changing the focal distance to the retina and bringing the image into sharp focus on the retina. (utah.edu)
  • A human eyeball cut in half to show the lens and the passage of light through it from the object ahead to the focus on the retina. (utah.edu)
  • The lens is a transparent, biconvex structure in the eye that, along with the cornea, helps to refract light to be focused on the retina. (wikipedia.org)
  • The lens, by changing shape, functions to change the focal distance of the eye so that it can focus on objects at various distances, thus allowing a sharp real image of the object of interest to be formed on the retina. (wikipedia.org)
  • His work led to much discussion in 16th century Europe over whether the principal organ of sight is the traditional Galenic crystalline humour or the Averroist aranea, which in turn led to the discovery that the retina is the principal organ of sight. (wikipedia.org)
  • Finally, the retina transmits nutrients to the lenses themselves. (wikipedia.org)
  • Rufus was the first to recognise a two-chambered eye, with one chamber from cornea to lens (filled with water), the other from lens to retina (filled with an egg white-like substance). (wikipedia.org)
  • A second, hand-held lens is used to examine the retina. (wikipedia.org)
  • proteins
  • Fernald also did research on eye evolution, showing that photoreceptor proteins have an ancient origin predating vision while lens proteins have arisen many times from different sources in different animal lineages. (wikipedia.org)
  • nucleus
  • During lenticular development, the hyaloid artery delivers nutrition and growth factors through the tunica vasculosa lentis, a vascular structure that envelopes the lens nucleus. (utah.edu)
  • Computer simulations showed that, for noise of 5 μm in the surface elevations, the GRIN is recovered with an accuracy of 0.003 and 0.010 in the refractive indices of the nucleus and surface of the lens, respectively. (osapublishing.org)
  • 4 Finally, a few hundred micrometers below the lens surface, fibers undergo programmed organelle destruction, whereby the nucleus and other membranous organelles are rapidly and synchronously degraded. (arvojournals.org)
  • Moving outwards from the central, oldest layer, the lens is split into an embryonic nucleus, the fetal nucleus, the adult nucleus, and the outer cortex. (wikipedia.org)
  • capsule of t
  • One embodiment of the invention is an ocular drug delivery method by penetrating at least the outer capsule of the lens with a fine conduit that creates a self-sealing aperture when it is removed, then introducing a drug into the lens through this aperture. (google.com.au)
  • Corneal
  • Corneal and lens surface elevations were analyzed by means of RMS (high order aberrations (HOAs), astigmatism, coma, trefoil and spherical). (arvojournals.org)
  • Eyes with transparent lens and cortical opacity were further classified by presence of WC (within 3-mm central optical zone (Central: C) and outside (Peripheral: P)). Lens power (LP) was calculated from refractive power, corneal refractive power, and axial length by Olsen's method (Acta Ophthalmol Scand. (arvojournals.org)
  • Sclera
  • The idea of the central crystalline lens was widely believed from Hunayn's period through the late 1500s.He describes the system behind the eyes that connects it to the brain, starting with the sclera, a thick, hard membrane which protects the inner parts of the nerves from injury. (wikipedia.org)
  • post-mortem time
  • Measurements were performed on 13 lenses from 8 cynomolgus monkey eyes obtained as part of a tissue-sharing protocol (age: 5.7 to 12.4 years, post-mortem time: 37+/-17 hours). (arvojournals.org)
  • Crystalline lenses (n = 41, aged 10 months-88 years, median post-mortem time 25 hours (interquartile range, 19-34 hours)) were isolated from eyes received from the Ramayamma International Eye Bank, Hyderabad, India. (arvojournals.org)
  • cataract formation
  • 13 . A method that minimizes cataract formation when an agent is provided to an ocular lens, the method comprising piercing the lens with a needle of 30 gauge or thinner, introducing an agent into the lens through the needle, and withdrawing the needle from the lens. (google.com.au)
  • Because of the risk of inducing cataract formation, penetrating the lens capsule to introduce drugs or other agents into the lens has not been favorably considered. (google.com.au)
  • A firm understanding of the embryology and development of the lens will provide great insight into the pathology associated with cataract formation. (utah.edu)
  • GRIN
  • A human eye model is proposed using a single equation for GRIN profile representation in crystalline lens. (osapublishing.org)
  • We present an optimization method to retrieve the gradient index (GRIN) distribution of the in-vitro crystalline lens from optical path difference data extracted from OCT images. (osapublishing.org)
  • The GRIN reconstruction method is based on a genetic algorithm that searches for the parameters of a 4-variable GRIN model that best fits the distorted posterior surface of the lens. (osapublishing.org)
  • osmotic
  • Researchers concluded that this osmotic swelling must be the result of an accumulation of abnormal metabolites or electrolytes in the lens. (wikipedia.org)
  • ocular
  • 1 . An ocular drug delivery method comprising penetrating at least an outer capsule of an ocular lens with a conduit to create an aperture in the lens and introducing a drug into the lens through the aperture, wherein the aperture is self-sealing upon removal of the conduit. (google.com.au)
  • 14 . A localized ocular drug delivery method comprising penetrating at least an outer capsule of an ocular lens with a conduit to create an aperture, providing an agent directly into the lens via the conduit through the aperture, and withdrawing the conduit wherein the agent is substantially confined within the lens. (google.com.au)
  • A cataract refers to any opacity of the ocular crystalline lens. (google.com.au)
  • optical
  • Y. Huang and D. T. Moore, "Human Eye Modeling Using a Single Equation of Gradient Index Crystalline Lens for Relaxed and Accommodated States," in International Optical Design , Technical Digest (CD) (Optical Society of America, 2006), paper MD1. (osapublishing.org)
  • The sagittal and coronal profiles of the lenses were imaged using a custom-built digital optical system based on the principle of shadowphotogrammetry. (arvojournals.org)
  • Water cleft located within the 3-mm central optical zone is an important factor of hyperopia due to decreased lens refractive power. (arvojournals.org)
  • Optical and structural development of the crystalline lens in childhood. (wikipedia.org)
  • citation needed] Treatment is done by changing the optical magnification properties of the auxiliary optics (corrective lenses). (wikipedia.org)
  • Contact lenses may also provide a better optical magnification to reduce the difference in image size. (wikipedia.org)
  • When the disparity appears to vary across the visual field (field-dependent aniseikonia), as may be the case with an epiretinal membrane or retinal detachment, the aniseikonia cannot fully be corrected with traditional optical techniques like standard corrective lenses. (wikipedia.org)
  • tilt
  • Before and after cataract surgery, the distribution of tilt magnitude and orientation of the lens or IOL were investigated using a prototype of IOLMaster700 (Carl Zeiss Meditec AG, Germany).Tilt orientation axis and tilt magnitude were derived from fitting a plane to 3D points sampled from 18 parabolas that were fitted to lens surfaces of 18 B-scans for each eye. (arvojournals.org)
  • We investigated the correlation between the tilt magnitude of lens or IOL and the axial length. (arvojournals.org)
  • Using a full-length OCT-based biometer, we could measure the tilt magnitude and orientation in both lens and IOL. (arvojournals.org)
  • The current study revealed that the tilt magnitude of the lens or IOL negatively correlated with axial length. (arvojournals.org)
  • Since the tilt-magnitudes before and after IOL implantation showed significant correlation, characteristics of the lens before surgery could be maintained after IOL implantation. (arvojournals.org)
  • The position of the lens center and the tilt angle of the lens were calculated by fitting the contour to a 10th-order even Fourier series containing tilt and decentration terms in a polar coordinate system using MATLAB's curve fitting toolbox. (arvojournals.org)
  • Three weeks after the surgery, a residue of heavy liquid was observed in the anterior chamber, even though the patient had an intact crystalline lens without any tilt or dislocation. (biomedcentral.com)
  • surfaces
  • The lenses of polarized sunglasses reduce glare reflected at some angles off shiny non-metallic surfaces, such as water. (wikipedia.org)
  • cortical
  • 50 yrs with transparent lens, and those with cortical opacity, develop hyperopia at the rate of 0.5D a decade with decreasing refractive power, whereas those with nuclear opacity became slightly myopic. (arvojournals.org)
  • contact lenses
  • The difference in magnification can also be eliminated by a combination of contact lenses and glasses (creating a weak telescope system). (wikipedia.org)
  • Effective IOL implants also entirely eliminate the need for glasses or contact lenses post-surgery for most patients. (wikipedia.org)
  • shape
  • The lens has an ellipsoid, biconvex shape. (wikipedia.org)
  • In the adult, the lens is typically circa 10 mm in diameter and has an axial length of about 4 mm, though it is important to note that the size and shape can change due to accommodation and because the lens continues to grow throughout a person's lifetime. (wikipedia.org)
  • One of the causes of the risks above is that the lens can rotate inside the eye if the PIOL is too short, if the eye was incorrectly measured, or because the sulcus has a slightly oval shape (the height is slightly smaller than the width). (wikipedia.org)
  • glasses
  • They can sometimes also function as a visual aid, as variously termed spectacles or glasses exist, featuring lenses that are colored, polarized or darkened. (wikipedia.org)
  • differentiation
  • Lenses from knockout mice grew normally and retained their transparency, suggesting that Livin does not have an indispensable role in fiber cell differentiation. (arvojournals.org)
  • The first stage of lens differentiation takes place when the optic vesicle, which is formed from outpocketings in the neural ectoderm, comes in proximity to the surface ectoderm. (wikipedia.org)
  • ciliary
  • The lens is suspended in place by the suspensory ligament of the lens, a ring of fibrous tissue that attaches to the lens at its equator and connects it to the ciliary body. (wikipedia.org)
  • optic
  • Concurrently, the optic vesicles invaginate causing an indentation on the lens placode called the lens pit (Fig. 2a). (utah.edu)