Cataract and cornea Miltos O. Balidis PhD, FEBOphth,ICOphth
CATARACT and Stromal opacities Keratoplasty Keratoconus Endothelial pathology
Scars PTK Trypan blue 0.01%. Work at the transparent side of cornea Mydriasis (>7) Hooks? Malyugin ring Sphincterotomies Paraxial illumination Endoillumination Stereo coaxial illumination OPMI LUMERA 700 Nishimura A, Kobayashi A, Segawa Y, Sugiyama K. Endoillumination-assisted cataract surgery in a patient with corneal opacity. J Cataract Refract Surg. 200;29(12):2277-2280.www.eyetube.net/video/cataractremoval-with-lumera-700-in-corneal-opacity-case
Combined Keratoplasty and Cataract Combined Biometry Ave Keratometry Rejection 14-31% PC Rupture Vitreous Visability Paraxial illumination Small incision Phaco ECCE IOL Open sky EXPULSIVE 2 stages Biometry Astigmatic correction Toric IOL ECR 2 Operations Inflammation, rejection
Cataract and Fuch s Average endothelial cell loss 8%-10% after phacoemulsification Viscoelastic of high ΜΒ / Low flow / Pulsed phaco / low power / full chop in the bag / avoid any intracameral drug Criteria for combined procedures Stromal edema, epithelial oedema CCT 640 (20% PKP for PBK) PBK in the other eye Seitzman GD, Gottsch, JD, Stark WJ. Cataract Surgery in Patients with Fuchs Corneal Dystrophy. Ophthalmol. 2005;112:441-446 Price FW, Price MO. Descemet s stripping with endothelial keratoplasty in 200 eyes: Early challenges and technique to enhance donor adherence. J. Cataract Refract Surg 2006; 32: 411-418
Cataract and Keratoconus Diopters \ procedures 0-0,75 0,75-1,5 1,5-2 2-3 >3 LTK LRI OCI CCL/PRK Toric IOL
Patient or method selection error Combined procedure (keratoplasty, cataract extraction and IOL implantation)? Advanced keratoconus, high surface irregularity index Central corneal opacities. Miscalculation may result in low-power IOL and extreme postop hyperopia Pre op aim for myopia. If high plus scleral lens required postoperatively, they have greater lens mass and reduced optic diameter IOL exchange
Biometry error Total corneal power calculation Standard correction factor (applied to the anterior radius of corneal curvature) Corneal refractive index of 1.3375 Refractive effect of posterior corneal surface Visual axis crosses the steepest portion of the cornea Keratoconus cone apex (typically displaced downwards and temporally). Accurate K s impossible High anterior surface irregularity Low Sim K repeatability (tear film abnormalities) Deep ACD than in the normal eye Influence the position of the IOL relative to the central cornea. SRK-T based on data obtained from linear regression, without incorporating the value for the ACD.
Mild and moderate keratoconus predictability is relatively good (<55d). The use of measured K s with a target of low myopia results in a low mean BPE* In advanced keratoconus there can be an unacceptably large hyperopic error BPE. High K s of advanced keratoconus will result in lowpower or negative-power IOL Standard K value should be considered *biometry prediction error BPE
Cataract surgery in difficult corneas Mr Bruce Allan Mr Vincenzo Maurino Dr Miltos Balidis