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Simulating the Mechanics of Lens Accommodation via a Manual Lens Stretcher
Published on: February 23, 2018
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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.
Eye & Contact Lens
|August 24, 2019
Summary
Contact lens-related corneal ulcers (CLRU) are less common than other corneal ulcers but are disproportionately caused by Pseudomonas. Staphylococcal species were the main cause of non-CLRU, and Acanthamoeba keratitis was exclusively linked to contact lens wear.
Area of Science:
- Ophthalmology
- Infectious Diseases
- Microbiology
Background:
- Corneal ulcers are a significant cause of vision loss.
- Contact lens wear is a known risk factor for microbial keratitis.
Purpose of the Study:
- To compare the characteristics and causative pathogens of infectious contact lens-related corneal ulcers (CLRU) versus non-CLRU cases.
- To identify demographic and microbiological differences between CLRU and non-CLRU.
- To analyze trends in causative organisms over time.
Main Methods:
- Retrospective review of corneal ulcer cases from 1999-2016.
- Data collected from ophthalmology and microbiology department databases.
- Comparison of demographic and microbiological data between CLRU and non-CLRU groups.
Main Results:
- Out of 677 corneal ulcers, 46% were CLRU.
- CLRU cases were more common in younger patients and women.
- Pseudomonas species predominated in CLRU (44%), while gram-positive bacteria, particularly Staphylococcal species, were more common in non-CLRU (64%).
- Acanthamoeba keratitis was exclusively associated with contact lens use.
- Fungal infections were primarily caused by filamentous organisms in both groups.
Conclusions:
- Contact lens-related corneal ulcers represent a significant proportion of microbial keratitis cases.
- Distinct causative pathogens are associated with CLRU (Pseudomonas) and non-CLRU (Staphylococcal species).
- Acanthamoeba keratitis is a specific complication of contact lens wear.
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