• Thumbnail for Astigmatism
    Astigmatism is a type of refractive error due to rotational asymmetry in the eye's refractive power. This results in distorted or blurred vision at any...
    38 KB (4,101 words) - 11:32, 22 August 2024
  • Thumbnail for Astigmatism (optical systems)
    system with astigmatism is one where rays that propagate in two perpendicular planes have different foci. If an optical system with astigmatism is used to...
    17 KB (1,934 words) - 12:23, 13 September 2023
  • Thumbnail for LASIK
    type of refractive surgery for the correction of myopia, hyperopia, and astigmatism. LASIK surgery is performed by an ophthalmologist who uses a femtosecond...
    59 KB (6,439 words) - 03:43, 15 September 2024
  • Thumbnail for Intraocular lens
    in substitution of the patient's crystalline, astigmatism is typically not corrected, as astigmatism is mainly attributable to a deformation of the cornea...
    43 KB (5,066 words) - 22:47, 11 September 2024
  • Thumbnail for Jackson cross cylinder
    particularly in determination of corrective lens power in patients with astigmatism. It is also used for testing near point of the eye. Jackson cross cylinder...
    7 KB (804 words) - 19:47, 16 June 2023
  • Thumbnail for Refractive surgery
    treat common vision disorders such as myopia, hyperopia, presbyopia and astigmatism. The first theoretical work on the potential of refractive surgery was...
    34 KB (3,901 words) - 00:41, 16 September 2024
  • Thumbnail for Three-mirror anastigmat
    all three main optical aberrations – spherical aberration, coma, and astigmatism. This is primarily used to enable wide fields of view, much larger than...
    12 KB (1,370 words) - 16:59, 25 June 2024
  • Thumbnail for Corrective lens
    most common use is to treat refractive errors: myopia, hypermetropia, astigmatism, and presbyopia. Glasses or "spectacles" are worn on the face a short...
    53 KB (6,362 words) - 01:42, 5 September 2024
  • Thumbnail for Bifocals
    presbyopia who also require a correction for myopia, hyperopia, and/or astigmatism. Benjamin Franklin is generally credited with the invention of bifocals...
    10 KB (1,001 words) - 19:55, 5 September 2024
  • A stigmator is a component of electron microscopes that reduces astigmatism of the beam by imposing a weak electric or magnetic quadrupole field on the...
    9 KB (825 words) - 13:27, 31 August 2024
  • Thumbnail for Pince-nez
    correct astigmatism. The disadvantages made this type fundamentally flawed for many wearers. The "astig"—named for its ability to manage astigmatism—or "bar-spring"...
    12 KB (1,546 words) - 07:12, 21 August 2024
  • Thumbnail for Farsightedness
    implantation. Other common types of refractive errors are near-sightedness, astigmatism, and presbyopia. In young patients, mild hypermetropia may not produce...
    23 KB (2,171 words) - 10:32, 20 August 2024
  • Thumbnail for Ptosis (eyelid)
    the drooping eyelid can cause other conditions, such as amblyopia or astigmatism, so it is especially important to treat the disorder in children before...
    30 KB (3,461 words) - 18:37, 5 September 2024
  • following Airy's development of methods to measure and correct ocular astigmatism. It has only recently[when?] become possible to measure the aberrations...
    17 KB (2,157 words) - 21:06, 3 June 2024
  • Thumbnail for Optical aberration
    common monochromatic aberrations are: Defocus Spherical aberration Coma Astigmatism Field curvature Image distortion Although defocus is technically the...
    58 KB (8,720 words) - 01:47, 17 September 2024
  • Thumbnail for Keratoconus
    may result in blurry vision, double vision, nearsightedness, irregular astigmatism, and light sensitivity leading to poor quality-of-life. Usually both...
    66 KB (7,263 words) - 18:13, 3 September 2024
  • Thumbnail for Corneal topography
    ). For example, the KISA% index (keratometry, I-S, skew percentage, astigmatism) is used to arrive at a diagnosis of keratoconus, to screen the suspect...
    11 KB (1,326 words) - 12:36, 27 July 2024
  • optical systems, even those exhibiting optical aberrations, including astigmatism, have at least one stigmatic pair. Stigmatism is applicable only in the...
    1,007 bytes (114 words) - 21:35, 20 January 2024
  • Thumbnail for Refractive error
    common types of refractive error are near-sightedness, far-sightedness, astigmatism, and presbyopia. Near-sightedness results in far away objects being blurry...
    37 KB (3,833 words) - 15:35, 10 September 2024
  • procedures. The Alpins Method uses vector mathematics to determine a goal for astigmatism correction and analyze factors involved if treatment fails to reach that...
    14 KB (1,746 words) - 21:28, 17 July 2024
  • Thumbnail for Noel Alpins
    is an Australian ophthalmologist who developed the Alpins method of astigmatism analysis used in refractive, corneal, and cataract surgery, used in the...
    6 KB (629 words) - 17:07, 27 August 2023
  • Thumbnail for Phacolytic glaucoma
    conducted to determine how much nearsightedness, farsightedness and/or astigmatism an individual may have. Additional specific measurements of the eye will...
    17 KB (2,218 words) - 16:51, 8 August 2024
  • lens is a lens used to diagnose a type of refractive error known as astigmatism. The Stokes lens also known as variable power cross cylinder lens, in...
    4 KB (356 words) - 00:01, 30 January 2023
  • because it provides high-quality outcomes with less surgically induced astigmatism than ECCE, no suture-related problems, quick rehabilitation, and fewer...
    43 KB (4,789 words) - 00:53, 9 May 2024
  • Thumbnail for Presbyopia
    of refractive error along with nearsightedness, farsightedness, and astigmatism. Diagnosis is by an eye examination. Presbyopia can be corrected using...
    22 KB (2,251 words) - 01:01, 15 September 2024
  • Thumbnail for Myopia in animals
    and have poor eyesight. In domestic animals, myopia, with or without astigmatism, occurs frequently. Evolved for low-light hunting, cats' eyes are proportionally...
    6 KB (642 words) - 23:09, 12 July 2024
  • Thumbnail for Eye examination
    Examples of refractive error are myopia, hyperopia, presbyopia and astigmatism. The errors are specified in diopters, in a similar format to an eyeglass...
    18 KB (2,190 words) - 18:03, 10 September 2024
  • Thumbnail for A. J. Cook
    Cook was declared legally blind in the second grade because of severe astigmatism, but wore contacts and thick "Coke bottle" glasses to correct her vision...
    23 KB (1,779 words) - 15:05, 1 September 2024
  • Thumbnail for Cylindrical lens
    the rod can be given as : Cylindrical lenses are prescribed to correct astigmatism. Cross cylinder, which is a combination of two cylindrical lenses with...
    5 KB (508 words) - 22:59, 31 March 2024
  • Thumbnail for Toric lens
    primarily in eyeglasses, contact lenses and intraocular lenses to correct astigmatism. A torus is the surface of revolution resulting when a circle with radius...
    5 KB (553 words) - 13:25, 21 December 2022