This article is more than 5 years old. Information may no longer be current.
Technique creates precise, well-centered anterior capsulotomy
Click Here to Manage Email Alerts
The use of an iris hook and pupil expansion ring for femtosecond laser-assisted cataract surgery in patients with insufficient mydriasis and an ectopic pupil produces a round, centrally located anterior capsulotomy opening, according to a report describing the new technique.
Adequate transpupillary access to the lens is necessary for successful femtosecond laser-assisted surgery. The use of a Malyugin ring for iris retraction can be insufficient for achieving the best position of the iris diaphragm, co-author Natalia Anisimova, MD, told Ocular Surgery News.
“An addition of the flexible iris hook can play an essential role to the proper centration of the pupil by moving an introduced Malyugin ring in the desired direction. A key advantage here is the minimally invasive approach with the two corneal incisions and a combination of the two leading iris retraction methods with the simultaneous ophthalmic viscosurgical device protection. Moreover, the technique can be well applied to FLACS procedures in cases of lens subluxation, insufficient mydriasis and a centered pupil, where, conversely, a pupil should be decentered to expose the subluxated lens,” Anisimova said.
The technique was performed in a 60-year-old woman with cataract who experienced a penetrating eye injury 15 years earlier. After implantation of the IOL, the hook and Malyugin ring were removed from the anterior chamber.
No postoperative increase in IOP was observed, and at 1 month postoperatively, reduction in endothelial cell density was not significant. The patient’s corrected distance visual acuity was 20/30 and uncorrected distance visual acuity was 20/50. It was likely that her corrected visual acuity was “associated with residual irregular corneal astigmatism from the original injury,” the researchers wrote.
The IOL was found to be well centered in the capsular bag, confirmed by ultrasound biomicroscopy.
The researchers noted that the technique offers several advantages for cataract surgery that may be complicated by insufficient mydriasis and an ectopic pupil.
“In our case, we combined the advantages of the pupil expansion device; that is, sufficient pupil dilation with the single iris hook, allowing pupil centration. This permitted unobstructed access to the central portion of the lens. Using only one hook lowers the risk for aqueous humor and OVD egress from the anterior chamber, which threatens anterior chamber collapse, and eliminates the need for corneal sutures,” the study authors wrote.
However, the technique offers several new challenges for surgeons who attempt a femtosecond laser-assisted cataract surgery, Anisimova said.
“Firstly, after introduction of the retraction complex, the surgeon should be aware of visible residual air bubbles, iris pigment or any other material present in the anterior chamber. The obstacles to the laser beam path should be removed from the anterior chamber, as it can lead to an optical blockage and subsequent capsular bridge formations or even an incomplete laser cut. Furthermore, another set of challenges is addressed to the extraocular portion of the iris hook with the fixation element that is located at the surface of the eye. This can frustrate achieving suction during the docking procedure or be the main reason of the extraocular inflow and elevate the risk of infection,” she said.
Anisimova noted that many believe manual capsulorrhexis is the most challenging step of cataract surgery, with a growing body of evidence suggesting that this procedure offers a better prediction of the effective lens position and can produce superior refractive outcomes. – by Matt Hasson and Robert Linnehan
- Reference:
- Malyugin B, et al. J Cataract Refract Surg. 2016;doi:10.1016/j.jcrs.2016.07.001.
- For more information:
- Natalia Anisimova, MD, can be reached at S. Fyodorov Eye Microsurgery Federal State Institution, 59-a, Beskudnikovsky Boulevard, Moscow, Russia 127486; email: vostoknata@gmail.com.
Disclosure: Anisimova reports no relevant financial disclosures.