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PRECIS: Eyes with corneal striae had steeper cornea, induced astigmatism, and higher corneal hysteresis, which implies a relationship between striae, corneal shape, and the cornea's resistance to deformation at low intraocular pressures. BACKGROUND: Anterior corneal striae (ACS) are associated with low intraocular pressure (IOP). However, the clinical significance of ACS is unclear. Here, we aim to evaluate differences in eyes with striae compared to eyes without striae. METHODS: Adults with ACS (cases) and without ACS (controls) ≥8 weeks after glaucoma surgery with an IOP ≤10▒mmHg were enrolled. Optical coherence tomography and optical biometry were performed. Corneal hysteresis (CH), defined as difference in pressure between corneal indentation and reformation in response to an air jet, was obtained by the ocular response analyzer. Hypotony maculopathy (HM) was defined as optic disc swelling, vascular tortuosity attributed to hypotony, or clinical presence of chorioretinal folds confirmed on OCT. RESULTS: One-hundred sixteen eyes (76 cases, 40 controls) were included. Cases had a lower IOP compared to controls (6.5±2.3 vs. 8.5±1, P<0.0001). A one mmHg increase in CH increased ACS odds (OR 1.51, P=0.01). A one diopter (D) increase in the flattest pre-surgical and post-surgical corneal power increased ACS odds by 1.83 (P=0.01) and 1.41 (P=0.02), respectively. Astigmatism increased in eyes with ACS by 1.11 D (P<0.001). ACS odds were increased with every one-minute increase in mitomycin-C duration (OR 1.58, P=0.047) and decreased with use of topical glaucoma medication (OR 0.62, P=0.03). VA decreased from logMAR 0.22 (20/33 Snellen) pre-surgery to 0.28 (20/38) post-surgery (P=0.008), independent of ACS. HM occurred in 19% of cases (P=0.05). A higher post-surgical CH increased HM odds (1.8 OR, P=0.003). HM predicted a 0.41▒mm decrease in axial length (P<0.0001), independent of IOP. CONCLUSION: ACS were associated with a steeper cornea, induced astigmatism, and higher CH, suggesting a relationship between striae, corneal shape, and the cornea's ability to resist deformations at lower IOP. CH, HM, and axial length shortening were associated independent of IOP.
Duke Eye Center, Duke University, Durham, NC 27705 Bascom Palmer Eye Institute, University of Miami Miller School of Medicine, Miami, Florida 33136.
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