Improvement in corneal scarring after removal of intracorneal lens

1. Improvement in corneal scarring after removal of intracorneal lens Ana G. Alzaga Fernandez, M.D., Samir A. Shah, M.D., M.S. Department of Ophthalmology and Eye Care Services, Henry Ford Hospital, Detroit, MI. Beach Eye Medical Group, Huntington Beach, CA. The authors have no financial interest in the subject matter of this poster.

2. Abstract • Purpose:  To report a case of improved corneal scarring and vision after removal of a PermaVision intracorneal lens. • Methods:  After adequately determining the patient’s candidacy for the placement of an intracorneal lens, the underwent PermaVision intracorneal lens placement in the left eye uneventfully in June 14, 2004. Corneal scarring was noted five years later and a medical regimen consisting of topical steroid drops was initiated. Due to limited improvement with the medical regimen, on April 22, 2010, the intracorneal lens was removed. • Results:  At one month after the initial placement of the PermaVision intracorneal lens, the patient’s uncorrected visual acuity was 20/20 with minimal peripheral haze. After five years, the uncorrected visual acuity had reduced to 20/60 and the best-corrected visual acuity to a subjectively blurry 20/30. She was found to have intrastromal scarring under the corneal flap overlying the implant. Topical corticosteroid therapy provided limited improvement. The intracorneal lens was removed uneventfully. In the first postoperative day, the patient’s uncorrected visual acuity was 20/40. At one month and subsequently at three months after the procedure, the patient’s best-corrected visual acuity was 20/30 with minimal residual intrastromal haze. The patient noted a substantial subjective visual improvement. • Conclusion:  Intracorneal lenses, such as PermaVision, should be cautiously used for treatment of hyperopia. Patients receiving these implants require long-term follow-up as scarring and a decline in best-corrected visual acuity can develop several years after surgery. Fortunately, removal of the intracorneal lens can provide visual improvement even years after the original surgery.

3. Introduction • Keratophakia is a procedure to correct vision by inserting a lenticule in the corneal stroma. Barraquer performed thousands of keratophakia procedures using donor corneal tissue and synthetic stromal inlays.1 • The importance of water and nutrient movement across the cornea from the aqueous humor led to the development of hydrogelhydroxyethylmethacrylate implants which increase the solute permeability.2-3 • The hydrogel lenses (Permalens), with a water content of 71%, proved to have excellent tissue bioavailability in non-human primates. However, glucose transport decreased with greater implant thicknesses.4 • Fenestrated hydrogelintracorneal implants (PermaVision) were developed to address these limitations. These lenses, which are composed of more than 70% water content and have a refractive index close to 1.376, were designed to correct hyperopia up to +6 diopters (D). The refractive effect of the lens is achieved through the alteration of the corneal shape.5-8 • We report a clinical complication after five years of PermaVisionintracorneal lens placement and recommended intervention.

4. Purpose • To report a case of improved corneal scarring and vision after removal of a PermaVisionintracorneal lens. • After adequately determining the patient’s candidacy for the placement of an intracorneal lens, the underwent PermaVisionintracorneal lens placement in the left eye uneventfully in June 14, 2004. Corneal scarring was noted five years later and a medical regimen consisting of topical steroid drops was initiated. Due to limited improvement with the medical regimen, on April 22, 2010, the intracorneal lens was removed. Methods and Materials

5. Case Report • A 53-year-old Caucasian lady with a history of PermaVisionintracorneal lens placement in the left eye in June 14, 2004 began with significant worsening of her vision at distance and near within the last year. Her cycloplegic refraction in the left eye preoperatively was: +2.25 +0.25 x 180 degrees with a visual acuity of 20/16. At near, with +2.25 add, her vision was 20/20. She was found to be left eye dominant. Her central corneal thickness in the same eye was 521 microns and in the periphery was 599 microns. Her keratometry measurement in the left eye was: 45.25/46.25 x 166 degrees. • One week postoperatively, her best-corrected visual acuity was 20/25 with the following refraction: -0.75 sphere. A month afterwards, her best corrected visual acuity was 20/16 with the following refraction: +0.75 +1.00 x 5 degrees. Trace haze at the edge of the flap was noted from four to eleven o’clock.

6. Case Report • After five years, the patient was unsatisfied with her vision at a distance and at near and subjectively complained of blur. Her best-corrected visual acuity was 20/30 and her cycloplegic refraction was -0.50 +0.50 x30 degrees. On slit lamp exam, she had superficial scarring on the flap overlying the implant and was started on topical steroids without improvement. • The patient underwent on April 22, 2010 removal of the implant. In the first postoperative day, the patient’s uncorrected visual acuity was 20/40. At one month and subsequently at three months after the procedure, the patient’s best-corrected visual acuity was 20/30 with minimal residual intrastromal haze. The patient noted a substantial subjective visual improvement.

7. Results • Five years after PermaVision intracorneal lens placement, the patient’s best-corrected visual acuity was 20/30. • Due to corneal scarring overlying the implant, the patient was started on topical corticosteroid therapy as initial medical intervention with minimal improvement. • Surgical removal of the implant was performed with subjective improvement of visual acuity and minimal residual intrastromal haze.

8. External and Slit Lamp Photographs of the Left Eye PermaVision Intracorneal Lens 5 years after placement PermaVision Intracorneal Lens 3 months after removal

9. OCT of the Anterior Segment After removal of implant Prior to removal of implant 4/19/10 4/30/10

10. Discussion • The concept of synthetic intracorneal implants or inlays has been investigated for over 40 years by Barraquer in 1964.1 • The new generation of soft intracorneal lenses, such as PermaVision intracorneal lenses, are an alternative for the correction of hyperopia.7 • The complications experienced in previous models for this type of implant are anterior stromal edema, recurrent epithelial erosion, and neovascularization.3,5,7 • In vivo confocal microscopy has shown significant keratocyte activation, diffuse extracellular deposits, decreased keratocyte density posterior to the intracorneal lens, and reduced epithelial thickness. The abnormal keratocyte activation suggests mechanical stress on the tissue or altered cytokine production from the metabolically stressed epithelial and stromal cells. 9,10 • Corneal sensitivity was markedly reduced in a series of patients 6 months after lens placement.8 • The depth of lens placement may play a role in the biocompatibility of the lens and its predictability. In a primate model, placing the lenses at one third to 60% depth achieved optimal results. 8,11 • Follow-up studies have been conducted up to two years after lens placement in human sighted eyes. Some studies suggest these lenses provide a stable and predictable way to correct moderate hyperopia.7 However, stromal opacification, decentration, decrease in visual acuity, night halos and glare occurred in several patients.7 Other trials, due to suboptimal results in their studies, recommend further research to improve the safety and quality of refractive outcomes with these devices.8

11. Conclusions • Intracorneal lenses, such as PermaVision, should be cautiously used for treatment of hyperopia. Patients receiving these implants require long-term follow-up as scarring and a decline in best-corrected visual acuity can develop several years after surgery. Fortunately, removal of the intracorneal lens can provide visual improvement even years after the original surgery.

12. References • Barraquer JI: Conducta de la cornea frente a los cambios de espesor (contribucion a la cirugiarefractiva). Arch Soc Am OftalmolOptom. 1964;5:81-7. • Dohlman CH, Refojo MF, Rose J: Synthetic polymers in corneal surgery. I. Glycerylmethacrylate. Arch Ophthalmol. 1967;77:252-8. • McCarey BE, Andrews DM: Refractive keratoplasty with intrastromalhydrogellenticular implants. Invest Ophthalmol Vis Sci. 1981;21:107-15. • McDonald MB, McCarey BE, Storie B, et al: Assessment of the long-term corneal response to hydrogelintrastromal lenses implanted in monkey eyes for up to five years. J Cataract Refract Surg. 1993;19:213-22. • Ismail MM: Correction of hyperopia with intracorneal implants. J Cataract Refract Surg. 2002;28:527-30. • Michieletto P, Ligabue E, Balestrazzi A, et al: PermaVisionintracorneal lens for the correction of hyperopia. J Cataract Refract Surg. 2004;30:2152-7. • Ismail MM: Correction of hyperopia by intracorneal lenses. Two year follow-up. J Cataract Refract Surg. 2006;32:1657-60. • Verity SM, McCulley JP, Bowman RW, et al: Outcomes of PermaVisionintracorneal implants for the correction of hyperopia. Am J Ophthalmol. 2009;147:973-7. • Petroll WM, Goldberg D, Lindsey SS, et al: Confocal assessment of the corneal reponse to intracorneal lens insertion and laser in situ keratomileusis with flap creation using Intralase. J Cataract Refract Surg. 2006;32:1119-28. • Lindsey SS, McCulley JP, Cavanagh HD, et al: Prospective evaluation of PermaVisionintracorneal implants using in vivo confocal microscopy. J Refract Surg. 2007;23:410-3. • McCarey BE, Storie BR, van Rij G, et alL Refractive predictability of myopic hydrogelintracorneal lenses in nonhuman primate eyes. Arch Ophthalmol. 1990;108:1310-5.