الفهرس 
ANATOMY OF THE CRYSTALLINE LENS AND THE ZONULAR APPARATUSOnly 14 pages are availabe for public view
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Abstract
Disruption or dysfunction of the zonular fibers of the lens, regardless of cause (trauma or heritable condition), is the underlying pathophysiology of ectopia lentis. The degree of zonular impairment determines the degree of lens displacement, which in turn plays a role in determining the optimal modality for management.
The management of ectopia lentis carries numerous challenges and options. from the clinical evaluation to the surgical approach, Patients with ectopia lentis require additional techniques and devices to ensure the best possible outcome. The continued refinement of surgical techniques and adjunctive prosthetic devices has led to improvements in the ability to achieve successful in-the-bag placement and centration of intraocular lenses while reducing complications. Optical correction by spectacles is not tolerated especially by infants. Partially occlusive contact lenses may be used to occlude the aphakic part allowing the phakic part of the field to be used.
Pars-plana lensectomy is an option of treatment. It allows a permanently clear visual axis and it spares the iris and the corneal endothelium. It makes it available to manage retinal problems associated with the condition or emerging during management.
Capsular tension rings (CTR), Modified CTR and Capsular tension segments have been used in cases where zonular weakness is identified.
The choice of IOL in eyes with deficiet capsule is challenging, especially in children. Childhood aphakia treated by contact lens or spectacle correction shows poor compliance.
Anterior Chamber IOL can induce recurrent uveitis, damage to AC angle and endothelial decompensation. However, recent advances in AC IOL design have yielded lenses that provide a safe, effective alternative to sutured PC IOLs. Anterior fixated iris-claw IOLs have been described to correct aphakia in children, with good visual results. But spontaneous subluxation of anterior-fixated iris-claw aphakic IOLs in children was reported. Requiring explantation because of corneal decompensation, uveitis, and secondary glaucoma.
Retropupillary fixation of an iris-claw IOL has the advantages of true posterior chamber implantation, which results in a deeper anterior chamber and greater distance to the corneal endothelium and has a lower intraoperative and postoperative risk profile than anterior fixation in adults.
Glued IOL technique is important in cases wih deficient iris – with the help or iris prosthesis - and this technique is devoid of suture-related complications associated with sutured scleral-fixated IOLs.