Phakic cadaver eye(horizontal meridian)

Pseudophakic cadaver eye(horizontal meridian)

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

Cataract x Myopia

• As a direct consequence of retinal damage lipid peroxidation is involved in the pathogenesis of cataract in diabetes and in severe myopia

Simonelli F, et al. Lipid peroxidation and human cataractogenesis in diabetes and severe myopia. Exp Eye Res 1989; 49:181-187