Transcorneal extrusion of a posterior chamber intraocular lens: an unusual presentation of intraocular lens dislocation.

Dear Editor,

Transcorneal extrusion of anterior chamber intraocular lens (IOL) through the surgical wound has been well documented in the literature1 and the erosion of anterior chamber lens through the sclera in patients with underlying connective tissue disorder has also been reported.2,3 Extrusion of a posterior chamber IOL through a diseased cornea at a site unrelated to the surgical incision is a very rare occurrence.4 We describe a case of transcorneal extrusion of a posterior chamber IOL following an episode of corneal ulcer.

A 65-year-old woman had undergone extracapsular cataract extraction in the right eye with posterior chamber IOL implantation in 1994, with recorded best corrected visual acuity in the early postoperative period of 20/60. She had a reportedly uneventful postoperative period until 2004 when she developed sudden diminution of vision, redness, pain and photophobia in the operated eye. She had reportedly taken treatment for a large corneal ulcer in the right eye, which subsequently healed. However, the poor vision, pain and irritation persisted and became especially severe in the last five days prior to presentation in July 2006. On initial examination visual acuity of the right eye was hand movements and that of the left eye was 20/80, with accurate projection of rays in all quadrants. Slit-lamp biomicroscopic examination of the right eye showed the polymethyl methacrylate (PMMA) optic (with dialing holes) lying over the leucomatous cornea with a circular depression in the central cornea identical in size and shape to the optic of the posterior chamber IOL. The tips of the two polypropylene haptics were loosely embedded in the leucomatous peripheral cornea, which showed superficial and deep vascularization [Fig. 1]. No view of the anterior segment was possible. Slit- lamp examination of the left eye showed a posterior chamber IOL but was otherwise unremarkable. B-Scan ultrasonography of the right eye revealed old vitreous opacities and attached retina. Fundus examination of the left eye was normal. Surgical removal of the lens was done and patient was prescribed topical third-generation fluoroquinolone, Gatifloxacin (Gatiquin eye drops, 0.3%, Cipla) instillation two-hourly, atropine (1%) drops twice a day; and the eye was patched to help re-epithelization. Patient was registered for penetrating keratoplasty at our center and would be taken up when the donor cornea becomes available.

Figure 1

Extruded posterior chamber intraocular lens through the cornea

Decompensation of cornea has been among the most common and visually disabling complications of IOL implantation since the introduction of this procedure. A decompensated cornea is more susceptible to serious secondary complications. If treatment is delayed, such an event can lead to transcorneal extrusion of the pseudophakos. In the present case the intraocular lens may have extruded through the site of the perforated corneal ulcer and had remained impacted on the corneal surface, allowing healing under it. We propose the term ′IOL sitting on the cornea′ for the clinical picture described in the present case report as this route and mode of total transcorneal extrusion of a posterior chamber IOL is an unusual occurrence.