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Updated: Jan 20, 2026

Simulating the Mechanics of Lens Accommodation via a Manual Lens Stretcher
Published on: February 23, 2018
Contact Lens Versus Non-Contact Lens-Related Corneal Ulcers at an Academic Center
Lisa Bennett1, Hugo Y Hsu, Shannon Tai
1Department of Ophthalmology (L.B., S.T., B.E., E.J.S., R.P., C.H., and S.L.E.), Saint Louis University Eye Institute, St. Louis, MO; Department of Ophthalmology (H.H.), Doheny Eye Institute, Los Angeles, CA; and Department of Ophthalmology (H.H.), David Geffen School of Medicine at UCLA, Los Angeles, CA.
Purpose:
To compare the infectious contact lens-related corneal ulcer (CLRU) and non-CLRU cases at Saint Louis University.
Methods:
Retrospective review of corneal ulcer cases identified by search of the ophthalmology and microbiology department databases between 1999 and 2016.
Results:
Six hundred seventy-seven cases of corneal ulcers were identified, of which 46% were CLRU. CLRU cases were seen more commonly in younger patients (P<0.001) and women (P=0.03) than non-CLRU cases. Many of the infections were vision-threatening as defined by central/paracentral location (73% CLRU and 71% non-CLRU [P=0.60]) and large size of ulcer >2 mm in 36% CLRU and 51% non-CLRU (P=0.002). Causative pathogen in cultured CLRU was predominately Pseudomonas species (44%, P<0.001 vs. the non-CLRU group), other gram-negative (6%), gram-positive (33%), fungi (13%), and Acanthamoeba (5%). Comparatively, cultured non-CLRU was predominately gram-positive (64%, P<0.001 vs. the CLRU group), gram-negative (26%), and fungi (11%). The combined oxacillin-resistant Staphylococcus aureus and coagulase-negative Staphylococcus isolates were 35% and 34%, respectively. Despite the progressive increase in the number of corneal ulcers seen, the annual trend for any one particular organism for either CLRU cases or non-CLRU cases did not change significantly.
Conclusions:
Most of the cases were non-CLRU. CLRU was disproportionately associated with Pseudomonas species and non-CLRU with Staphylococcal species. Fungal infections were predominately caused by filamentous organisms in both groups. Acanthamoeba keratitis was exclusively associated with CL use.
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