Every eye surgeon’s most un-wanted: moving IOLs

Subluxated & Dislocated

IOLs on the Move

by Brooke Herron

When subluxated or dislocated lenses require surgical management, technique is important — not only surgically to prevent complications — but also in the intraocular lens (IOL) fixation technique. To unpack the various options, the Middle East and Africa Council of Ophthalmology (MEACO) put on a session titled Subluxated and Dislocated Lenses: The Way to Go from Pole to Pole on the third day of the 37 th World Ophthalmology Congress (WOC2020 Virtual®).

Dislocated IOLs can be complicated

Lens dislocation can be congenital, as in the cases of systemic disease, or acquired — most commonly as a result of cataract surgery or ocular trauma, began Prof. Remzi Avci from the Retina Eye Hospital in Turkey.

Unfortunately, dislocated lenses or fragments can result in a variety of complications including cystoid macular edema (CME), phacoantigenic uveitis, phacoantigenic glaucoma, retinal tears or detachment and corneal edema, he continued. “The [severity] of the complication is also concerned with the size of the retained lens fragments, the severity of the trauma, and the length of time between dislocation and surgery.”

For anterior segment surgeons encountering this issue, Prof. Avci cautioned that there are several things not to do: “They should avoid manipulation that could cause vitreous loss and/or vitreoretinal traction — such as, do not perform phaco in case of vitreous prolapse into the anterior chamber; do not perform sponge vitrectomy; and do not introduce instruments into the vitreous to remove fragments.

Watch for complications

“Subluxated lenses are a real challenge with different scenarios,” said University of Cairo Professor Yehia Mostafa, adding that it might be seen preoperatively, or it could occur intraoperatively or as a result of a complication.

He also advised that surgeons should be ready with different ideas, plans and tools (i.e. capsular tension rings, 3-piece IOLs, capsular hooks and iris hooks, among others).

So, how to proceed? While dropped cortical fragments might resolve themselves with observation, Prof. Avci said that dropped nucleus/fragments should be removed with vitrectomy. “Treatment of a dislocated lens with pars plana vitrectomy (PPV) is a safe and effective approach,” he said. “The most important predictor of final VA is a less complicated clinical course without any associated complications like retinal detachment, CME or glaucoma.”

Further, the surgical technique depends on the grade of nucleus, continued Prof. Avci. “In soft nucleus, you can use the vitrectomy probe, in hard nucleus (grade 3-4) we prefer phacofragmentation, and in hard grade 5 cataracts, extraction via limbal incision may be preferred.”

IOL fixating techniques

In addition to surgical management, there are also various ways to implant an IOL. In the absence of capsular bag support, Dr. Sami Al Rabiah from the Al Rabiah Medical Center in Kuwait, recommends the glued IOL technique.

For an IOL to be fixated in the eye, the best anatomical, pathological and optical position is in the capsular bag,” said Dr. Rabiah. “But if you have an absent or insufficient capsular support, you have to find another way to fixate your IOL.”

This can be achieved through scleral (one-point or segmental) or iris fixation. In segmental fixation, a big segment of the loop is fixated into the sclera, and this is either the glued IOL or Yamane technique, explained Dr. Rabiah before going into a detailed, step-by-step instruction for the glued IOL technique.

Dr. Abdul Aziz Badla from the Saudi German Hospital in Dubai, United Arab Emirates, also commented on scleral fixation: “IOL scleral fixation with Gortex suture is a safe procedure with encouraging results, especially when PPV is needed,” he concluded.