JUNIPER
PUBLISHERS- JOJ Ophthalmology
Abstract
The migration of a dexamethasone intravitreal implant
(Ozurdex) into the anterior chamber can cause corneal decompensation
which may necessitate removal. The implant often fragments when forceps
are used and standard vitrectomy instrumentation is suboptimal due to
the small opening of the port relative to the size of the implant. We
propose the use of a phacoemulsification hand piece for removal of the
implant, which has a lumen large enough to assume the implant, infusion
to maintain the depth of the anterior chamber, and the ability to
emulsify the implant.
Keywords: Phacoemulsification; Dexamethasone; Implant; MigrationIntroduction
The Dexamethazone intravitreal implant [1]
has been approved by the United States Food and Drug Administration for
the treatment of macular edema associated with retinal vein occlusion,
noninfectious uveitis involving the posterior segment, and diabetic
macular edema. The implant is contraindicated in patients whose
posterior lens capsule is torn or ruptured because of the risk of
migration into the anterior chamber. However, laser capsulotomy in
pseudophakic patients is not a contraindication [1].
The migration of the implant into the anterior chamber, especially if
soon after its implantation, can cause corneal decompensation which may
necessitate its removal [2,3]. Reported techniques for removal include the use of a vitrector, forceps, viscoelastic, or a Sheets glide [4,5].
However, the implant often fragments when forceps are used and standard
vitrectomy instrumentation is often ineffective due to the small
opening of the port relative to the size of the implant [3].
Others have reported successful relocation of the implant into the
posterior segment with mydriatics and head positioning, external digital
force, or manipulation with a needle in the clinic [6-8]. Nevertheless, the implant may still migrate into the anterior chamber yet again [9].
Technique
The experimental surgical video provided demonstrates
a beveled, clear corneal incision created with a 2.5 millimeter
keratome blade in a porcine eye after inflation of the chamber with
viscoelastic. A phacoemulsification hand piece (CENTURION® Vision
System, Alcon Laboratories, Inc. Fort Worth, TX) was then introduced
into the anterior chamber and used on a high-vacuum setting to engage
the implant on its long axis, allowing for efficient emulsification and
aspiration.
Discussion
We propose the use of a phacoemulsification handpiece
for removal of the implant, which has a lumen large enough to assume
the implant, infusion to maintain the depth of the anterior chamber, and
the ability to emulsify the implant. The diameter of the Ozurdex
implant is 0.46 milimeters, while the diameter of the opening of many
phacoemulsifcation probes is 0.5-0.9 milimeters. This technique utilizes
the procedures and instrumentation of cataract phacoemulsification that
are familiar to all ophthalmologists.
Declarations
Presented at the Sociedad Panamericana de Enfermedades Inflamatorias Oculares, Las Vegas, NV, November 14, 2015.
Competing Interests
TA is a consultant for Allergan. AM has no relevant interests.
Authors' contributions
Conception of project and preparation of manuscript - AM and TA.
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