Ординатура / Офтальмология / Английские материалы / Optics Retinoscopy and Refractometry_Lens_2005

abbreviations, 80-81 aberrations, types of, 23-24 absolute hyperopia, 18-19 accommodation

amplitude of, 65-66 focusing power, 15-16 IOLs and, 25

for refractive errors, 17 accommodative IOLs, 26 adaptive optics, 22

age

accommodation, 17 diminishing focus, 16

AK (astigmatic keratotomy, 21 ametropia, 17

amplitude of accommodation, 65-66 angle of incidence, 4, 12-13

angle of reflection (law of reflection), 12-13 angle of refraction, 4

aniseikonia, 20 anisometropia, 20 arm length, 35 aspheric lenses, 5

aspherical cornea, 14-15 astigmatic dial, 54, 58 astigmatism

aberrations, 23 classifications, 19 cylindrical lenses for, 8 refining correction, 63-64 retinoscopy procedure, 38-39

barrel distortion, 5 bifocals, 69-70 binocular balance, 61-63

cardinal points, 8-9

Case Option Directory exercises astigmatism with glasses

minus cylinder, 98-104 plus cylinder, 88-94

guidelines, 84 protocol, 84-85

unknown refractive error minus cylinder, 118-125 plus cylinder, 108-117

ciliary muscle, 16, 26 clear lensectomy, 25 coma aberrations, 23 complex lens system, 8 concave mirrors, 13 convergence, 5

convex mirrors, 13

Copeland's design, retinoscope, 29, 31-32, 4041

cornea

aspherical, 14-15 corneal astigmatism, 19 corneal topography, 22 refractive surgery, 21

corpuscular theory, 1, 2 critical angle, 13-14 cross cylinder, 49, 55-59 crystalline lens, 15-16

cycloplegic eyedrops, 18-19 cycloplegic refractometry, 63 cylinder axis, 42-43, 49, 56, 59, 64 cylinder power, 57, 59-60 cylindrical lenses, 8

divergent light, 1, 5

duochrome (bichrome) test, 62-63 dynamic cross cylinder test, 66-67 dynamic retinoscopy, 42

electromagnetic spectrum, 2 emergent ray, 4

emmetropia, 17, 19-20, 25-26

epi-LASIK (epithelial laser assisted in-situ keratomileusis), 21

excimer laser, 21

focal length, 3. See also lens power focal line, 8

focal points

for plus-powered lens, 8 reflex movement and, 37 four-diamond charts, 64

geometric optics, theories, 2-14. See also lenses

hyperopia IOLs for, 26

plus-powered lens for, 5 refractive surgery, 21-22 retinal image size, 19-20 types of, 18-19

image rays, 5 incident ray, 4

interpupillary distance, 11

IOLs (intraocular lenses), types of, 25-26 IR (index of refraction), 3

irregular astigmatism, 19

Jackson cross cylinder, 58, 58-59

Knapp's rule, 20

LASEK (laser epithelial keratomileusis), 21 LASIK (laser assisted in-situ keratomileusis),

21

latent hyperopia, 18-19 latent nystagmus, 69 law of reflection, 12-13 law of refraction, 4-5

lens power. See also focal length compared to focal length, 3 determining, 1, 3

measuring, 2-3 lenses

cardinal points, 8-9 cylinders, 8

induced prism, 10-12 optical cross, 12 prisms, 1, 7-8 reflection, 12-15

retinal image size, 19-20 retinoscopy lens, 35

SE (spherical equivalent), 10 spherical, 7-8

transposition, 9-10 lenticular astigmatism, 19

manifest hyperopia, 18-19 metric system, 76-77

minus cylinder, retinoscopy procedure, 40 minus-powered lens. See also refractometry

focal point for, 8 for myopia, 18

parallel light entering, 5 refining sphere power, 60

minus sphere method, determining amplitude of accommodation, 66

multifocal IOLs, 26 myopia

corneal refractive surgery, 21 IOLs for, 26

minus-powered lens for, 17, 18

near addition, 65-68 neutrality, 37-38, 41 neutralization, reflex, 29 nystagmus, latent, 69

object rays, 5

ophthalmic lenses, types of, 4 optical center, 7

optical cross lenses, 12

optics components, 2 exercises, 26-28

geometric optics, 2-14 physical optics, 2 physiologic optics, 14-17 refractive errors, 17-19 refractive surgery, 20-26 retinal image size, 19-20

paraboline test, 54-55, 58 pentafoil aberrations, 24 physical optics, theories, 2

physiologic optics. See also schematic eye refractive errors, 17-19

schematic eye, 10-17 theories, 14-20

pincushion effect, 5 pinhole disk, 60-61

plus cylinder, retinoscopy procedure, 40 plus-powered lens. See also refractometry

focal point for, 8 for hyperopia, 5

neutralized against movement, 29 neutralized with movement, 29 refining sphere power, 60 spherical, 7

power of mirrors, 13 Prentice's rule, 11 primary principal plane, 8 prism diopter, 7

prism dissociation tests, 61-62 prisms

calculating power of, 7-8 definition, 1

induced, 10-12 rotary prism, 61

PRK (photorefractive keratectomy), 21 pseudophakia (artificial lens), 25

push plus, 49

push-up method, determining amplitude of accommodation, 66

quadrafoil aberrations, 24

radical retinoscopy, 41 ray diagrams, 2

real image formation, 2, 5 reflection, 12-15 reflection by mirrors, 2 reflective surface, 1 reflex

intercept and, 33-34 movement, 36-38

refractive errors

surgical correction of, 21-22 types of, 17-19

visual acuity and, 69 refractive surgery

considerations, 20-21 cornea and, 21

intraocular refractive surgery, 25-26 wavefront analysis, 22-26

refractometry

binocular balance, 61-64 cycloplegic, 63

cylinder refinement

minus cylinder technique, 57-60 plus cylinder technique, 53-57

definition, 50

latent nystagmus, 69 near addition, 65-68 patient preparation, 50-51 pinhole disk, 60-61 refinement, 49, 60 refractor alignment, 52 refractor anatomy, 50 spectacles of, 69-70 sphere determination, 53 starting point, 52 stenopaic slit, 64-65 strategies, 51-52

vertex distance, 68 refractor, 30-31

retinal image size, 19-20 retinoscope, 31-32, 39 retinoscopy

basic principles, 32-38 considerations, 29-30 dynamic, 42 equipment, 30-32 exercises, 44-47 procedure, 38-41 radical, 41

refining cylinder axis and power, 42-43 retinoscopy lens, 35

reversing sleeve position, 40-41 RK (radial keratotomy), 21 rotary prism, 61

rotating cylinder axis, 64

schematic eye

axial length, 16-17 cornea, 14-15

crystalline lens, 15-16 pupil, 15

retinoscopy, 30 scissors movement, 37

SE (spherical equivalent) lenses, 10 secondary principal plane, 8-9 Shack-Hartmann wavefront sensor, 23, 24 Snell's law, 4-5

speed of light

in a vacuum, 1, 2 in water, 3

through a medium, 3-4 sphere

for best near vision, 68 plus-powered, 35

spherical aberrations, 23 spherical ametropia, 38 spherical lenses, 7-8 spherocylindrical combination, 8 stenopaic slit, 64-65

straddle cross method, retinoscopy, 42-43 streak retinoscopes, 29

Sturm's conoid, 8 Super Vision, 22

telescopes, 22

third-order aberrations, 23 total internal reflection, 13-14

transposition lenses, calculating corrections, 9- 10

trefoil aberrations, 24

vergence, 5, 33-34 vertex distance, 68 virtual images, 5 visual acuity, 69, 77 visual axis, 38

wave theory, 2 wavefront analysis

aberrations, 23-24

historical perspectives, 22-23 variabilities, 25

white light, 2

working distance, 34-37

Zernike, Frits, 23 Zernike nodes, 23, 24 zonules, 16