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keratoconus

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keratoconus

  1. 1. Keratoconus diagnosis and treatment Sedaghat M.R M.D MASHAD EYE RESEARCH CENTER Khatam-al-Anbia Hospital
  2. 2. Keratoconus <ul><li>Preoperative topographic screening prior to keratorefractive surgery has largely focused on keratoconus </li></ul><ul><li>A significant subset of patients who seek keratorefractive surgery may have a mild form of keratoconus </li></ul>
  3. 3. Keratoconus prevalence(1) <ul><li>Prevalence of clinically significant KCN is 1 in 3000 </li></ul><ul><li>With more widespread use of topography is more common than previously thought </li></ul><ul><li>Up to 8% of myopes presenting for refractive surgery have suggestive topographic analysis </li></ul>
  4. 4. <ul><li>In refractive surgeon clinic overall : 8% </li></ul><ul><li>1-2% by excluding these: </li></ul><ul><ul><li>Instability of refraction </li></ul></ul><ul><ul><li>Reduced BSCVA </li></ul></ul><ul><ul><li>Myopia>-10D </li></ul></ul><ul><ul><li>Astigmatism>2D </li></ul></ul><ul><li>10-20% in patients: </li></ul><ul><ul><li>With high Astigmatism especially if oblique </li></ul></ul>Keratoconus prevalence(2)
  5. 5. Keratoconus prevalence(3) <ul><li>Incidence of KCN in general population: 0.05% </li></ul><ul><li>Incidence in persons considering refractive surgery: 6% to 12% </li></ul><ul><li>Incidence of form-fruste KCN or suspect as high as 17% of patient seeking refractive surgery </li></ul>
  6. 6. Incidence of keratoconus 0.03% – 0.05 % for keratoconus 6 % - 17% for form fruste keratoconus?
  7. 7. Important etiologic factors <ul><li>Eye rubbing (prevalence among KCN patients ranges from 33% to 66%) </li></ul><ul><li>Contact lens wear (corneal micro trauma) </li></ul><ul><li>Vigorous eye rubbing has frequently been observed in patients with Down's syndrome & may explain the high incidence of associated corneal hydrops </li></ul>
  8. 8. SYMPTOMS <ul><li>Symptoms are highly variable and depend on the stage of the progression of the disorder </li></ul><ul><li>Progressive visual blurring and /or distortion </li></ul><ul><li>Early in the disease there may be no symptoms and may be noted simply because the patient cannot refracted to a clear 20/20 corrected vision </li></ul>
  9. 9. <ul><li>Early in the course of the disease , VA may be normal even in symptomatic patients </li></ul><ul><li>Contrast sensitivity measurement may detect visual dysfunction before VA loss </li></ul>SYMPTOMS
  10. 10. <ul><li>High irregular astigmatism with a scissoring reflex on retinoscopy is typical in established keratoconus </li></ul><ul><li>Irregular corneal astigmatism is confirmed when keratometry is performed and the central mires can not be superimposed </li></ul>SIGNS OF KCN
  11. 11. SIGNS OF KCN <ul><li>External signs : </li></ul><ul><ul><li>Munson” sign </li></ul></ul><ul><ul><li>Rizzuti phenomenon </li></ul></ul><ul><li>Slit-lamp findings: </li></ul><ul><ul><li>Stromal thining </li></ul></ul><ul><ul><li>Posterior stress lines(vogt,s striae) </li></ul></ul><ul><ul><li>Iron ring ( fleischer ring ) </li></ul></ul><ul><ul><li>Scarring - epithelial or subepithelial </li></ul></ul><ul><li>Retroillumination signs: </li></ul><ul><ul><li>Scissoring on retinoscopy </li></ul></ul><ul><ul><li>Oil droplet sign (charleaux”) </li></ul></ul>
  12. 12. Munson's sign <ul><li>In advanced keratoconus the corneal protrusion may cause angulation of the lower lid on down gaze </li></ul>
  13. 13. Rizzuti phenomenon <ul><li>Sharply focused beam of light near the nasal limbus ,produced by lateral illumination of the cornea in patients with advanced keratoconus </li></ul>
  14. 14. Slit lamp examination <ul><li>An eccentrically located ectatic protrusion of the cornea </li></ul><ul><li>The apex is usually inferior to pupillary axis: </li></ul><ul><ul><li>Round or nipple – central cone , smaller diameter </li></ul></ul><ul><ul><li>Larger oval or sagging cone may extend to the limbus </li></ul></ul>
  15. 15. SIGNS OF KCN <ul><li>Qualititative criteria for diagnosis of KCN include: </li></ul><ul><li>Corneal thining </li></ul><ul><li>Vogt,s striae </li></ul><ul><li>Fleischer ring </li></ul><ul><li>Scissoring of retinoscopic reflex </li></ul>
  16. 16. Stromal thining <ul><li>A hallmark of keratoconus is corneal thining which occurs at the apex of the cone (the point of maximal protrusion) </li></ul>
  17. 17. Posterior stress lines (Vogt,s striae) <ul><li>Fine vertical lines in the deep stroma, just anterior to descemet,s membrane that parallel the axis of the cone and disappear transiently on gentle digital pressure </li></ul>
  18. 18. Corneal Scarring epithelial or subepithelial <ul><li>Superficial linear scars at the corneal apex </li></ul><ul><li>These results from ruptures in bowman,s layer </li></ul>
  19. 19. Iron ring ( fleischer ring ) <ul><li>The ring is a partial or complete annular line commonly seen at the base of the cone </li></ul><ul><li>The ring is formed from hemosiderin pigment deposited in the basal epithelium </li></ul>
  20. 20. Retroillumination and retinoscopy signs <ul><li>Scissoring on retinoscopy </li></ul><ul><li>Oil droplet sign (charleaux ”) </li></ul>
  21. 21. Corneal hydrops <ul><li>Acute descemet membrane rupture and corneal hydrops </li></ul>
  22. 22. Detection of Keratoconus <ul><li>Retinoscpy </li></ul><ul><li>Slit lamp </li></ul><ul><li>Keratometry </li></ul><ul><li>Keratoscpy </li></ul>Vogt’s striae fleisher’ ring
  23. 23. Signs / Symptoms <ul><li>Frequently changing spectacle Rx and axis of astigmatism </li></ul><ul><li>Poor repeatability of subjective refraction </li></ul><ul><li>Ghosting/ monocular diplopia </li></ul><ul><li>Glare at night </li></ul><ul><li>Haloes around lights </li></ul><ul><li>Blurred/ distorted vision </li></ul><ul><li>Scissors reflex: (swirling retinoscopy reflex) </li></ul><ul><li>Distorted/ irregular keratometer mires with steep readings </li></ul><ul><li>Prominent corneal nerves </li></ul>
  24. 24. Signs / Symptoms <ul><li>KC often results in irregular astigmatism which can severely limit distance and night vision in a way that can not always be corrected using glasses </li></ul><ul><li>Ghosting/ monocular diplopia </li></ul><ul><li>Glare at night </li></ul><ul><li>Haloes around lights </li></ul><ul><li>Blurred/ distorted vision </li></ul>
  25. 25. Signs / Symptoms <ul><li>KC often results in irregular astigmatism which can severely limit distance and night vision in a way that can not always be corrected using glasses </li></ul>
  26. 26. Keratoconus course <ul><li>Keratoconus ,classically, has its onset at puberty and is progressive until the third to fourth decade of life, when it usually arrests (80%) </li></ul><ul><li>It may ,however, commence later in life and progress or arrest at any age (20%) </li></ul>
  27. 27. Keratoconus course
  28. 28. Evaluation and diagnosis of keratoconus History and family history Follow up evaluation Slit -lamp exams Keratoscopy- Keratometry Corneal thickness - pachymetry Topography - Orbscan –Pentacam
  29. 29. Keratoscopy
  30. 30. What is topography?
  31. 31. What is topography?
  32. 32. Keratoconus pattern: <ul><li>non-Keratoconus cornea general symmetry overall with no exsessive steepening </li></ul>Keratocunus cornea extreme asymmetrical and inferior steepening
  33. 33. KCN clinical classification
  34. 34. KCN clinical classification <ul><li>Clinical keratoconus </li></ul><ul><li>Early or subclinical keratoconus </li></ul><ul><li>Keratoconus suspect </li></ul>
  35. 35. Clinical keratoconus <ul><li>Clinical slit-lamp signs of keratoconus </li></ul><ul><li>Scissoring of retinoscopic reflex with fully dilated pupil </li></ul><ul><li>KCN topographic pattern </li></ul>
  36. 36. Early or subclinical keratoconus <ul><li>No clinical slit-lamp findings </li></ul><ul><li>Scissoring of retinoscopic reflex with fully dilated pupil </li></ul><ul><li>KCN topographic pattern </li></ul>
  37. 37. Keratoconus suspect <ul><li>No clinical slit-lamp findings </li></ul><ul><li>No scissoring of retinoscopic reflex with fully dilated pupil </li></ul><ul><li>KCN topographic pattern </li></ul>
  38. 38. Keratoconus suspect inferior steepening
  39. 39. Topographic patterns of keratoconus <ul><li>Inferior steepening without bowtie pattern specially more prominent temporally </li></ul><ul><li>Asymmetrical bow tie (AB) & inferior/superior steepening (IS-SS) </li></ul><ul><li>Central steepening +/- superimposed with asymmetrical bowtie pattern </li></ul><ul><li>Asymmetic /symmetric bow tie (AB) & skewed radial axes (SRAX) </li></ul>
  40. 40. Keratoconus pattern: Inferior steepening without bowtie pattern specially more prominent temporally
  41. 41. Topographic patterns of keratoconus <ul><li>Inferior steepening without bowtie pattern specially more prominent temporally </li></ul><ul><li>Asymmetrical bow tie (AB) & inferior steepening (IS) </li></ul><ul><li>Central steepening +/- superimposed with asymmetrical bowtie pattern </li></ul><ul><li>Asymmetic /symmetric bow tie (AB) & skewed radial axes (SRAX) </li></ul>
  42. 42. Keratoconus pattern: asymmetrical bow tie (AB) & inferior steepening(IS)
  43. 43. Topographic patterns of keratoconus <ul><li>Inferior steepening without bowtie pattern specially more prominent temporally </li></ul><ul><li>Asymmetrical bow tie (AB) & superior steepening (SS) </li></ul><ul><li>Central steepening +/- superimposed with asymmetrical bowtie pattern </li></ul><ul><li>Asymmetic /symmetric bow tie (AB) & skewed radial axes (SRAX) </li></ul>
  44. 44. Keratoconus pattern: asymmetrical bow tie (AB) & superior steepening(SS)
  45. 45. Topographic patterns of keratoconus <ul><li>Inferior steepening without bowtie pattern specially more prominent temporally </li></ul><ul><li>Asymmetrical bow tie (AB) & inferior/superior steepening (IS-SS) </li></ul><ul><li>Unusual Central steepening </li></ul><ul><li>Asymmetic /symmetric bow tie (AB) & skewed radial axes (SRAX) </li></ul>
  46. 46. Keratoconus pattern: Central keratoconus central unusual steepening without bow tie
  47. 47. Topographic patterns of keratoconus <ul><li>Inferior steepening without bowtie pattern specially more prominent temporally </li></ul><ul><li>Asymmetrical bow tie (AB) & inferior/superior steepening (IS-SS) </li></ul><ul><li>Central steepening with superimposed with asymmetrical bowtie pattern </li></ul><ul><li>Asymmetic /symmetric bow tie (AB) & skewed radial axes (SRAX) </li></ul>
  48. 48. Keratoconus pattern: Central steepening, superimposed with asymmetrical bowtie- slightly irregular astigmatism asymmetrical central hourglass
  49. 49. Topographic patterns of keratoconus <ul><li>Inferior steepening without bowtie pattern specially more prominent temporally </li></ul><ul><li>Asymmetrical bow tie (AB) & inferior/superior steepening (IS-SS) </li></ul><ul><li>Central steepening with superimposed with symmetrical bowtie pattern </li></ul><ul><li>Asymmetic /symmetric bow tie (AB) & skewed radial axes (SRAX) </li></ul>
  50. 50. Globus topographic type of KCN
  51. 51. Topographic patterns of keratoconus <ul><li>Inferior steepening without bowtie pattern specially more prominent temporally </li></ul><ul><li>Asymmetrical bow tie (AB) & inferior/superior steepening(IS-SS) </li></ul><ul><li>Central steepening +/- superimposed with asymmetrical bowtie pattern </li></ul><ul><li>Asymmetic /symmetric bow tie (AB) & skewed radial axes (SRAX) </li></ul>
  52. 52. Keratoconus pattern: Symmetic(SB) /asymmetric bow tie (AB) & (SRAX)
  53. 53. Topographic patterns of keratoconus <ul><li>Inferior steepening without bowtie pattern specially more prominent temporally </li></ul><ul><li>Asymmetrical bow tie (AB) & inferior/superior steepening(IS-SS) </li></ul><ul><li>Central steepening +/- superimposed with asymmetrical bowtie pattern </li></ul><ul><li>Asymmetric bow tie (AB) & skewed radial axes (SRAX) </li></ul>
  54. 54. Keratoconus pattern: asymmetrical bow tie & skewed radial axes (AB/SRAX)
  55. 55. Topographic patterns of keratoconus <ul><li>Inferior steepening without bowtie pattern specially more prominent temporally </li></ul><ul><li>Asymmetrical bow tie (AB) & inferior/superior steepening(IS-SS) </li></ul><ul><li>Central steepening +/- superimposed with asymmetrical bowtie pattern </li></ul><ul><li>symmetric bow tie (AB) & skewed radial axes (SRAX) </li></ul>
  56. 56. Keratoconus pattern: symmetrical bow tie & skewed radial axes (AB/SRAX)
  57. 57. Classification <ul><li>Keratoconus can be classified by cone shape , central keratometric reading or progression </li></ul><ul><li>The simplest classification systems are based on keratometric reading or shape </li></ul>
  58. 58. Classification <ul><li>Based on severity of curvature </li></ul><ul><li>Mild : <45 D in both meridians </li></ul><ul><li>Moderate : 45-52 D in both meridians </li></ul><ul><li>Severe : >52 D in both meridians </li></ul><ul><li>Advanced : >62 D in both meridians </li></ul>
  59. 59. Classification <ul><li>Based on shape of cone </li></ul><ul><li>Nipple small diameter (5 mm); round shape; easiest to fit with contact lenses </li></ul><ul><li>Oval large diameter (>5 mm); often displaced inferiorly; more difficult to fit with lenses, most common by topography </li></ul><ul><li>Globus largest diameter (>6 mm); 75% of cornea affected; most difficult to fit with lenses </li></ul>
  60. 60. KCN treatment <ul><li>Stopping progression of ectasia: </li></ul><ul><ul><li>Corneal cross- linking </li></ul></ul><ul><li>Improving vision by : </li></ul><ul><ul><li>Glasses </li></ul></ul><ul><ul><li>Contact lenses </li></ul></ul><ul><ul><li>surgery </li></ul></ul>
  61. 61. COLLAGEN CROSS LINKING <ul><li>Collagen cross linking has recently been proposed as a method for stopping the progression of keratoconus and is used with or without the use of corneal ring or intraocular lens </li></ul><ul><li>This involves applying riboflavin ( vitamin drops ) to the cornea and then blasting it with Ultraviolet light </li></ul>
  62. 62. Keratoconus course With cross-linking Without cross-linking
  63. 63. The inventors of X- linking <ul><li>The excellent research by </li></ul><ul><li>Prof Theo Seiler & </li></ul><ul><li>Dr. Eberhard Spörl </li></ul><ul><li>during the past 13 yearsis now summarized in an outstanding clinical device for UV cross linking </li></ul>
  64. 66. eligible to cross - linking <ul><li>The diagnosis of keratoconus must be confirmed based on clinical examination findings and corneal topography (mapping) </li></ul><ul><li>There must be evidence of progression of the keratoconus occurring over the last 12 months: </li></ul><ul><ul><li>changes in contact lens prescription, spectacle prescription </li></ul></ul><ul><ul><li>measurements of corneal shape (keratometry or topography) </li></ul></ul>
  65. 67. NOT eligible to cross - linking <ul><li>Age less than 16 or older than 35 to 40 years </li></ul><ul><li>Pregnancy or breastfeeding </li></ul><ul><li>Past history of Herpes Simplex Keratitis </li></ul><ul><li>Cornea is too thin (less than 400 microns) </li></ul><ul><li>Other corneal disease or scarring is present </li></ul><ul><li>There is a known allergy to Riboflavin </li></ul>
  66. 68. X - Linking and eye? <ul><li>X-linking of human collagen is a physiologic process, stiffening of connective tissue : </li></ul><ul><ul><ul><li>( diabetes and aging ) </li></ul></ul></ul><ul><li>diabetes is a protection factor against KCN </li></ul>
  67. 69. X - Linking and cornea?
  68. 70. Collagen cross linking (CCL) <ul><li>Collagen cross-linking in the cornea using riboflavin (B 2 ) - UVA treatment leads to a significant increase in mechanical stiffness of the corneal </li></ul><ul><li>Sp örl et al Opthalmologe 1997 </li></ul><ul><ul><li>Increased rigidity by more than 300% </li></ul></ul><ul><ul><li>Young ’ s modulus increased by 4.5 x </li></ul></ul>
  69. 71. Increase in mechanical stiffness of the corneal by cross - linking Eberhard Spörl, TU Dresden
  70. 72. Principle of action CCL or UVA-X <ul><li>X-linking : new chemical bonds are induced </li></ul>Collagen cross-linking
  71. 73. X - Linking and cornea?
  72. 74. X-linking
  73. 75. UVA 370 nm Irradiance 3 mW/cm 2 for 30 min Dose of 5.4 J/cm 2
  74. 76. Treatment procedure
  75. 77. Treatment procedure <ul><li>Epithelium scraped off after anesthetic </li></ul><ul><li>Photosensitizer riboflavin B 2 0.1% in 20% Dextran </li></ul><ul><li>UVA 370 nm </li></ul><ul><li>Irradiance 3 mW/cm 2 for 30 min </li></ul><ul><li>Dose of 5.4 J/cm 2 </li></ul><ul><li>CL and antibiotic drops </li></ul>
  76. 78. UV-X SYSTEM Automated timing and intensity control Intensity calibration for safe use Easy mounting and positioning Transportable in compact case
  77. 79. Treatment: improving of vision <ul><li>The first line of treatment is to fit rigid gas permeable (RGP) contact lenses </li></ul><ul><ul><li>Because this type of contact is not flexible, it creates a smooth, evenly shaped surface to see through </li></ul></ul><ul><ul><li>However, because of the cornea's irregular shape, these lenses can be very challenging to fit </li></ul></ul><ul><ul><li>This process often requires a great deal of time and patience </li></ul></ul><ul><li>When vision deteriorates to the point that contact lenses no longer provide satisfactory vision, corneal transplant may be necessary to replace the diseased cornea with a healthy one </li></ul>
  78. 80. Rigid gas permeable (RGP) contact lenses
  79. 81. Referral criteria for corneal graft <ul><li>In 15% to 20% of the keratoconic population, a corneal transplant is eventually required </li></ul><ul><li>The patient should be referred for transplant if any of the following generally accepted referral criteria are met: </li></ul><ul><ul><li>contact lens intolerance especially with recurrent abrasions </li></ul></ul><ul><ul><li>inability to fit the patient with a contact lens (frequent lens loss) </li></ul></ul><ul><ul><li>decreased vision (scarring) which prevents the patient from doing necessary visual tasks </li></ul></ul><ul><ul><li>a large cone with progressive thinning in the periphery </li></ul></ul><ul><ul><li>danger of perforation( extremely rare in keratoconus) </li></ul></ul>
  80. 82. Various types of surgery are available for the patient with keratoconus <ul><li>Penetrating keratoplasty : </li></ul><ul><ul><li>keratoconic cornea is prepared by removing the central area of the cornea, and a full - thickness corneal button is sutured in its place </li></ul></ul>
  81. 83. Various types of surgery are available for the patient with keratoconus <ul><li>Penetrating keratoplasty : </li></ul><ul><ul><li>Generally, the second eye is not grafted until the first eye is successfully rehabilitated </li></ul></ul><ul><ul><li>success rate PK of is 90% to 95% </li></ul></ul><ul><ul><li>Keratoconus patients are younger than the majority who are grafted for other reasons </li></ul></ul><ul><ul><li>Contact lenses are often required after this procedure for best visual correction </li></ul></ul><ul><ul><li>Patients can have LASIK or PRK on their transplants and become relatively independent of glasses or contact lenses </li></ul></ul>
  82. 84. Various types of surgery are available for the patient with keratoconus <ul><li>Lamellar keratoplasty (partial corneal transplant) : </li></ul><ul><ul><li>The cornea is removed to the depth of posterior stroma, and the donor button is sutured in place </li></ul></ul><ul><ul><li>This technique is technically difficult, and visual acuity is inferior to that obtained after penetrating keratoplasty </li></ul></ul><ul><ul><li>This technique requires less recovery time, and poses less chance for corneal graft rejection or failure </li></ul></ul><ul><ul><li>Its disadvantages include vascularization and haziness of the graft </li></ul></ul>
  83. 85. Modified Melles technique-DALK
  84. 86. Modified Melles technique-DALK after 2w
  85. 87. Modified Melles technique-DALK after 1.5 m
  86. 88. 6 m after DALK big bubble technique
  87. 89. INTACS –FERRARA ring <ul><li>A method for flattening the cornea that is too steep and making a patient more contact lens tolerant is the insertion of  ring into the cornea </li></ul><ul><li>This procedure is good for patients: </li></ul><ul><ul><li>contact lens intolerant </li></ul></ul><ul><ul><li>to avoid a corneal transplant </li></ul></ul><ul><ul><li>K readings are not in excess of  58 Diopters </li></ul></ul>
  88. 90. INTACS –FERRARA ring <ul><li>It is also useful for individuals with keratoconus who want to improve their present vision with or without contact lenses </li></ul><ul><li>This technique involves the insertion of two arc like plastic segments into the middle of the cornea to flatten the cornea </li></ul>
  89. 91. <ul><li>Ring segments , acrylic Perspex CQ (Mediphacos) with an inner radius of curvature of 2.5 mm, thickness from 150 to 350 mic, and arc length 150 degree </li></ul><ul><li>Optical correction is achieved with central corneal flattening, which is directly proportional to the ring thickness </li></ul><ul><li>Ring segment thickness and arc lengths were selected according to a previously described Ferrara nomogram </li></ul>FERRARA ring
  90. 92. The ring segments have a prism format; the flat posterior surface is implanted facing the corneal endothelium FERRARA ring
  91. 93. <ul><li>The FICRS implantation technique is relatively easy for a corneal surgeon, but attention must be paid to some important details including : </li></ul><ul><ul><li>correct tunnel construction, starting at 80% depth of corneal thickness at the location of the radial incision </li></ul></ul><ul><ul><li>ring segment centration based on central corneal reflex </li></ul></ul><ul><ul><li>correct selection of ring segment position in the flat corneal meridian </li></ul></ul>FERRARA ring
  92. 94. Mechanism of Action Steepest Meridian
  93. 96. 250  / 210° 250  / 90° 200  /120°
  94. 98. FICR: male 20 yrs OS preoperative exams Subj ref: plano -6 × 160 Cyclo ref: overcylinder KR average: 56.99 D Cyl of KR: -11.27 D × 162 AL : 24.15mm AC depth: 4.17 mm CCT:422 μ UCVA: 3/10 BSCVA=5/10
  95. 99. FICR: male 20 yrs OS preoperative exams
  96. 100. FICR: male 20 yrs OS preoperative exams <ul><li>Ring size :0.35/0.35mm </li></ul><ul><li>Ring axis : 70 degree </li></ul>
  97. 101. FICR: male 20 yrs OS postoperative exams Subj ref: plano Cyclo ref: -0.25 -3.5 × 90 KR average: 48.22 D Cyl of KR: -6.56 D × 37 UCVA: 8/10 BSCVA=8/10
  98. 102. FICR: male 20 yrs OS topographic change after FICR
  99. 103. FICR: male 20 yrs OS topographic change after FICR Subj ref: plano Cyclo ref: -0.25 -3.5 × 90 KR average: 48.22 D Cyl of KR: -6.56 D × 37 UCVA: 8/10 BSCVA=8/10 Subj ref: plano -6 × 160 Cyclo ref: overcylinder KR average: 56.99 D Cyl of KR: -11.27 D × 162 UCVA: 3/10 BSCVA=5/10
  100. 104. PHAKIC INTRAOCULAR LENSES <ul><li>Patients who are extremely nearsighted more than -8 to -10D might benefit from phakic intraocular lenses </li></ul><ul><li>Currently there are two type of these lenses approved by the FDA –the Verisyse / Artisan and the Visian ICL </li></ul><ul><li>This will be an exciting new opportunity for a select number of patients with keratoconus who could potentially improve their vision without the need for corneal surgery </li></ul>
  101. 105. Toric artisan: male 23 yrs OD preoperative exam Subj ref: -18.5 -5 × 110 (0.5) Cyclo ref: -16.75 - 6.25 × 6 KR average: 56D Cyl of KR: 6 × 10 AL : 26.66mm AC depth: 4.39mm CCT:408 μ Artisan IOL: - 17 – 5.5 × 18
  102. 106. Toric artisan: male 29 yrs OD preoperative exam
  103. 107. Toric artisan: male 23 yrs OD preoperative exam
  104. 108. Toric artisan: male 23 yrs OD preoperative exam
  105. 109. Toric artisan: male 23 yrs OD IOL calculation
  106. 110. Toric artisan: male 23 yrs OD preoperative exam
  107. 111. Toric artisan: male 29 yrs OD postoperative exams <ul><li>Subj ref: plano </li></ul><ul><li>UCVA: 10/10 </li></ul><ul><li>BSCVA=10/10 </li></ul><ul><li>Cyclo ref: - 0.5 -1 × 165 </li></ul><ul><li>KR average: 57 D </li></ul>

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