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Patient of Dr. G. Baikoff, Marseille, France
(Courtesy: S. Phillips, Ultralink)
Phakic anterior chamber lens:Vivarte™
Patient of Dr. H. Matamoros,Madrid Spain
(Courtesy: S. Phillips, Ultralink)
Phakic posterior chamber lens:PRL
Phakic posterior chamber IOLs
• Cells involved in crystalline lens and capsular bag opacification• Evolution of designs of PPCIOLs• Relevant aspects of fixation and sizing• Sizing issue: New studies• Surgical implantation• Relationship between cataract and myopia• Cataractogenesis
• Specimens analyzed in our Center• Mechanisms• Review of the literature• Classification of cataracts after phakic IOL implantation?
Surgical implantation
• Nd:YAG laser iridotomies: 2 superior iridotomies; placed 90 degrees apart (to avoid pupillary block); performed 1 or 2 weeks before surgery
-Cataractogenetic effect?
-Contribute to pigment deposition on the IOLs
-1 single surgical iridectomy may be performed intraoperatively (risk of bleeding)
Surgical implantation
2) Incision (foldable lenses, thus, small incision; may be planned to correct pre-existing astigmatism)
3) Injection of viscoelastics (important to protect adjacent tissues and to allow the lens to unfold in a controlled manner)
4) Lens insertion:
-ICL injector/forceps
-PRL special forceps/injector
Surgical implantation
5) Placement of the haptics behind the iris (spatula/hook)-No pressure should be placed on the crystalline lens
6) Pupil contriction with miotic agents7) Viscoelastic removal (irrigation or irrigation/aspiration)8) Wound closure
Postoperative treatment: -Steroid/antibiotic (4 weeks)-Oral acetazolamide (48 hours) retained
viscoelastics
Surgical implantation
-The crystalline lens should ideally not be touched at all during the surgery
-Many opportunities to have accidental contact with the anterior capsule of the crystalline lens
-Anterior capsule trauma may lead to crystalline lens opacities months later
Phakic posterior chamber IOLs
• Cells involved in crystalline lens and capsular bag opacification• Evolution of designs of PPCIOLs• Relevant aspects of fixation and sizing• Sizing issue: New studies• Surgical implantation• Relationship between cataract and myopia• Cataractogenesis
• Specimens analyzed in our Center• Mechanisms• Review of the literature• Classification of cataracts after phakic IOL implantation?
Cataract x Myopia
• Excess incidence of myopic refraction in cataract patients
• Age-related nuclear sclerosis causes refractive change towards myopia
Brown NAP, Hill AR. Cataract: The relation between myopia and cataract morphology. Br J Ophthalmol 1987; 71:405-414
Cataract x Myopia
• Use of eyeglasses by age 20 years (indicator of myopia) increase the risk of cataract
Leske MC, et al. The lens opacities case-control study. Risk factors for cataract. Arch Ophthalmol 1991; 109:244-251
Harding JJ, et al. Risk factors for cataract in Oxfordshire: diabetes, peripheral neuropathy, myopia, glaucoma and diarrhoea. Acta Ophthalmol 1989; 67:510-517.
Cataract x Myopia
• Moderate to high myopia has an association with age-related cataract
• For lower levels of myopia this relationship has been disputed
• Early-onset myopia: strong and independent risk factor for cataract
Lim R, et al. Refractive associations with cataract: the Blue Mountains Eye Study. Invest Ophthalmol Vis Sci 1999; 40:3021-3026
Cataract x Myopia
• “High myopia is complicated by the frequent and early development of cataracts”.
Metge P, Donnadieu M. Myopia and cataract. Revue du Praticien 1993; 43:1784-1786