Corneal Manifestations of Ocular Demodex Infestation

Purpose: To report the corneal manifestations in eyes with Demodex infestation of the eyelids. Design: Noncomparative, interventional case series. Methods: This retrospective review included six patients with Demodex blepharitis who also exhibited corneal abnormalities, which led to suspicion of limbal stem cell deficiency in three cases. All patients received weekly lid scrubs with 50% tea tree oil and a daily lid scrubs with tea tree shampoo for a minimum of six weeks. Improvement of symptoms and corneal and conjunctival signs were evaluated. Results: All six patients exhibited ocular irritation and conjunctival inflammation, while meibomian gland dysfunction (n = 5), rosacea (n = 4), and decreased vision (n = 3) also were noted despite prior treatments with oral tetracycline, topical steroids with antibiotics, and lid scrub with baby shampoo. These patients were proven to have Demodex folliculorum (n = 6) and Demodex brevis (n = 3) by microscopic examination of epilated lashes. Their corneal manifestation included superficial corneal vascularization (six eyes of five cases), marginal corneal infiltration (two eyes of two cases), phlyctenule-like lesion (one eye of one case), superficial corneal opacity (two eyes of two cases), and nodular corneal scar (two eyes of two cases). After treatment, the Demodex count was reduced from 6.8 ± 2.8 to 1 ± 0.9 (standard deviation; P = .001). All patients showed dramatic resolution of ocular irritation, conjunctival inflammation, and all inflammatory, but not scarred, corneal signs; three patients showed improved vision. Conclusions: A variety of corneal pathologic features together with conjunctival inflammation, commonly noted in rosacea, can be found in patients with Demodex infestation of the eyelids. When conventional treatments for rosacea fail, one may consider lid scrub with tea tree oil to eradicate mites as a new treatment.