Contact Lens-induced Limbal Stem Cell Deficiency

Abstract

Limbal stem cell deficiency (LSCD) is a pathologic condition caused by the dysfunction and/or destruction of stem cell precursors of the corneal epithelium, typified clinically by corneal conjunctivalization. The purpose of this review is to critically discuss a less well-known cause of limbal stem cell disease: contact lens (CL) wear. A literature search was conducted to include original articles containing patients with CL-induced LSCD. This review describes epidemiology, diagnostic strategies, pathogenesis, differential diagnosis, and treatment modalities for this condition.

Keywords: contact lens; corneal conjunctivalization; limbal stem cell deficiency; limbal stem cells.

Figure 1. Contact lens-induced limbal stem cell deficiency

A. Early involvement of the superior cornea. There is whorl-like epithelium (red arrow) adjacent to an area of punctate staining (yellow area), which is the earliest sign of LSCD. B Superior involvement of the cornea, characteristic of moderate CL-induced LSCD. C. Late-staining fluorescein diffusely in a whorled pattern as a confluent sheet across the cornea in late-stage CL-induced LSCD. D. Characteristic superior involvement of corneal epithelium.

Figure 2. Contact lens-induced limbal stem Cell deficiency - 360° disease

A. CL-induced LSCD with whorl-like epithelium throughout the cornea. B. Another example of diffuse (360 degrees) disease along with stromal changes. C. 360° disease with superficial neovascularization. D, E. Fluorescein staining in a patient with diffuse CL-induced LSC disease (two weeks after discontinuing CL wear).

Figure 3. Confocal microscopy images of limbal stem cell deficiency

In vivo confocal microscopic appearance of the cornea in CL-induced LS CD. Confocal images demonstrating the presence of conjunctival type epithelium adjacent to the more organized basal corneal epithelial cells. (Courtesy of Drs. Alessandro Abbouda and Pedram Hamrah.)

Figure 4. Etio-pathogenesis of contact lens-induced limbal stem cell deficiency

Multifactorial etiology of CL-induced LSCD. A key component is limbal epithelial stress, which may stem from a combination of dry eye, CL solutions/preservative toxicity, mechanical trauma and hypoxia. Inflammation can develop secondarily or can be due to other conditions such as rosacea/MGD and atopy.*LSCD = Limbal Stem Cell Deficiency.*CL = Contact Lens.*MGD = meibomian gland dysfunction.

Figure 5. Response to treatment in CL-induced LSCD

A, B. Patient with CL-induced LSCD presenting with opaque epithelial sheet from superior limbus extending into visual axis with visual acuity reduced to 20/100. C. The same patient after 6 months of treatment which included completely stopping CL wear, topical steroids, cyclosporine and punctal occlusion. Final visual acuity was 20/25.

Figure 6. Proposed treatment algorithm for CL-induced LSCD

*Return to soft CL use can be considered in patients who will comply with good follow-up and most often in patients where disease is suspected to develop secondary to preservative-containing lens cleaning solutions. These patients should use preservative-free cleaning methods (such as hydrogen peroxide solution), switch to disposable daily lenses, ensure proper fit, and decrease amount of daily wear time. Any recurrence of disease should lead to prompt discontinuation of wear. **Keratoplasty will only be successful long-term in patients with a healthy limbal niche; it cannot be utilized until LSCD has resolved or been fully treated with limbal transplant. Note: Further research is needed to test the efficacy of our treatment model.