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SELECTION of PATIENTS PIOLs. António Marinho, MD PhD Departamento de Cirurgia Refractiva Hospital Arrábida PORTO PORTUGAL. WHY PHAKIC IOLs?. Phakic IOL ’ s are ideal for high ametropias because: High predictability even in very high ametropias Stability of refraction
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SELECTION of PATIENTSPIOLs António Marinho, MD PhD Departamento de Cirurgia Refractiva Hospital Arrábida PORTO PORTUGAL
WHY PHAKIC IOLs? Phakic IOL’s are ideal for high ametropias because: • High predictability even in very high ametropias • Stability of refraction • Preserve accomodation • No loss (usually gains) of lines of BSCVA
WHEN PHAKIC IOLs? • Mínimal Age • 18 years • exceptions • anisometropia • Stable refraction in the last 18 months • Above 50 years • low ametropia • LASIK • high ametropia • CLE • Myopia • - Subjective Refraction • under - 7D : LASIK • above -7D: Phakic IOL • Main Factor : Pachymetry • Hyperopia • - Cycloplegic Refraction • under + 3D : LASIK • above + 4D: Phakic IOL • Main factor: Keratometry
INCLUSION CRITERIAGeneral • Stable refraction • No intraocular diseases (diabetes without retinopathy and well controlled glaucoma are relative contraindications,but any history of UVEITIS is absolute contraindication) • Ectatic disorders of the cornea are NOT contraindications
INCLUSION CRITERIASpecific • Anterior chamber anatomy (AC depth and AC size) • Endothelium profile • Iris shape Pupil Size • Perfect Surgery
Anterior chamber depth • AC depth (central) • > 2.80mm (endothelium to natural lens) • Higher IOL power may need deeper AC (see Ophtec tables) • Importance of critical distance
How to measure the AC depth ? • US biometer (not precise) • Orbscan • Scheimpflug (Pentacam) • OCT (Visante,SL-OCT)
How to evaluate the AC ? • US Biometer (not precise) • Orbscan • OCT (Visante,SL-OCT)
Anterior chamber size • Angle to angle distance (AC phakic IOLs) • Sulcus to sulcus distance (ICL) • Not important for iris-fixated IOLs (“one size fits all)
How to measure AC Size ? • White to white (caliper,Orbscan,IOL master)---- not reliable • OCT (good to angle, but not to sulcus to sulcus)
Iris shape • Avoid convex iris • Most important in Hyperopia (clearance) • Possibility of posterior synechia
Preop ACD too small <2,8mm Iris = convex
Pupil Size • Mesopic pupil <6.0mm • Artisan 5mm Mesopic Pupil <7.0mm • Artisan 6mm Artiflex/Acrysof/ICL • Glare and halos
Endothelium Profile • Endothelial cell count: • 21 to 25 years 2800 cells/mm • 26 to 30 years 2650 cells/mm • 31 to 35 years 2400 cells/mm • 36 to 45 years 2200 cells/mm • > 45 years 2000 cells/mm • Endothelial cell shape (avoid high polymagatism)
Endothelial Cell Count • Before Surgery (inclusion criteria) • 3 months after (shows surgical trauma) • Yearly afterwards (if important decrease EXPLANT)
Perfect Surgery • Atraumatic Surgery • Use cohesive viscoelastic • Center the IOL with the pupil (recheck at the end) – Artisan/Artiflex • Take all the visco out • Attention to post-op medication
WHICH PIOL? • Angle- supported ? • Posterior chamber ? • Iris- supported ?