Posteriorly Dislocated Intraocular Lenses
Posterior chamber intraocular lenses (PCIOLs) may become dislocated despite seemingly satisfactory capsular support at the time of the initial surgery. Factors to consider when placing a sulcus-fixated IOL include the presence of zonular dehiscence, total amount of anterior capsular support (eg, >180°), size of the eye, and haptic-to-haptic diameter of the IOL. Foldable IOLs have a 12.5–13.0-mm haptic-to-haptic length. This length, which is frequently smaller than the sulcus-to-sulcus diameter into which these haptics must fit, may contribute to postoperative subluxation or dislocation of the IOL. A flexible IOL may also become dislocated following Nd:YAG laser capsulotomy performed soon after cataract surgery. Late dislocation of the IOL (from several months to decades after surgery) is less common but may occur as a result of trauma or spontaneous loss of zonular support in eyes with pseudoexfoliation syndrome. Treatment options in such cases include observation only, surgical repositioning, IOL exchange, or IOL removal.
In vitrectomy for posteriorly dislocated IOLs, all vitreous adhesions to the IOL are removed in order to minimize vitreous traction to the retina when the lens is manipulated back into the anterior chamber. The IOL may be placed into the ciliary sulcus provided there is adequate support. If capsular support is inadequate, the IOL may be fixated by suturing the haptics to the iris (iris fixation) or sclera (scleral fixation) or by placing the haptics into intrascleral tunnels (intrascleral fixation). Alternatively, the PCIOL can be removed through a limbal incision and exchanged for an anterior chamber IOL (ACIOL; Video 20-6).
Vitrectomy for retrieval of posteriorly dislocated IOL.
Courtesy of Colin A. McCannel, MD.
Smiddy WE, Flynn HW Jr. Managing retained lens fragments and dislocated posterior chamber IOLs after cataract surgery. Focal Points: Clinical Modules for Ophthalmologists. San Francisco: American Academy of Ophthalmology; 1996, module 7.
Excerpted from BCSC 2020-2021 series: Section 10 - Glaucoma. For more information and to purchase the entire series, please visit https://www.aao.org/bcsc.