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Purpose: To characterize the corneal biomechanical properties of glaucoma eyes by comparing the dynamic Scheimpflug biomechanical parameters between untreated glaucoma and control eyes., Methods: Cross-sectional observational data of dynamic Scheimpflug analyzer (Corvis ST) examinations were retrospectively collected from 35 eyes of 35 consecutive patients with untreated normal tension glaucoma and 35 eyes of 35 healthy patients matched on age and IOP. Ten biomechanical parameters were compared between the two groups using multivariable models adjusting for IOP, central corneal thickness, age, and axial length. The Benjamini-Hochberg method was used to correct for multiple comparison., Results: In multivariable models, glaucoma was associated with smaller applanation 1 time (P < 0.001, coefficient = -0.5865), applanation 2 time (P = 0.012, coefficient = -0.1702), radius (P = 0.006, coefficient = -0.5447), larger peak distance (P = 0.011, coefficient = 0.1023), deformation amplitude ratio at 1 mm (P < 0.001, coefficient = 0.072), and integrated radius (P < 0.001, coefficient = 1.094). These associations consistently indicate greater compliance of the cornea in glaucoma eyes., Conclusions: Untreated normal tension glaucoma eyes were more compliant than healthy eyes. The greater compliance (smaller stiffness) of normal tension glaucoma eyes may increase the risk of optic nerve damage. These results suggest the relevance of measuring biomechanical properties of glaucoma eyes.

Purpose: The purpose of this study was to clarify correlations between corneal deformation parameters measured with a dynamic Scheimpflug analyzer and baseline factors such as axial length, intraocular pressure (IOP), age, central corneal thickness (CCT), and corneal curvature., Methods: Ninety-six eyes of 96 healthy subjects (mean 55.2 ± 16.1 years of age) were examined using a dynamic Scheimpflug analyzer. Eighteen of 35 deformation parameters were selected for analyses based on measurement reliability and clinical relevance. The associations between corneal deformation parameters and axial length, IOP, age, CCT, and average corneal power were evaluated using multivariate regression analyses., Results: Deformation parameters were correlated significantly with axial length (n = 13), IOP (n = 13), age (n = 8), and CCT (n = 6) in the multivariate models. Longer axial length corresponded with greater corneal deformability, less viscous damping, and less movement of the entire eye. Higher IOP was associated with greater corneal resistance and less movement of the entire eye. Older age was associated with less corneal deformability and greater movement of the entire eye. Corneal curvature was correlated significantly with only three deformation parameters., Conclusions: This study clarified the substantial impact of axial length, age, and IOP on the biomechanical responses of the cornea and the entire eye. In contrast, corneal curvature did not affect most of the deformation parameters. The current results confirmed the importance of corneal biomechanics, especially in eyes with longer axial length and in older subjects.

Purpose: We measured the three-dimensional geometric profile around the optic nerve head (ONH) using swept-source optical coherence tomography (SS-OCT) in highly myopic eyes., Methods: We studied 114 highly myopic eyes (<-6.0 diopters [D]) of 114 patients without glaucoma. Eyes were examined using the prototype SS-OCT. The retinal pigment epithelium (RPE) and chorioscleral interface were traced, and the mean y-axis coordinates of 24 sectors were calculated in circular peripapillary (3.4-mm diameter) images. The peripapillary tilting index (PTI) was calculated by subtracting the mean y-axis coordinate of the RPE in a sector from the mean of all sectors. The main outcome measures were the PTI and its association with the staphyloma depth from the OCT images and the ovality index (OI) of the ONH and peripapillary atrophy (PPA) area from fundus photographs., Results: The PTI differed significantly (P < 0.0001) among the 24 sectors and was lowest at the inferotemporal sector (-1930.76 μm). The minimal PTI value was in the temporal to inferotemporal sectors in 88 (77.2%) eyes and was correlated significantly with the OI (P < 0.0001) and age (P < 0.001) but not with the equivalent refractive error or axial length. The minimal PTI was correlated significantly with the PPA area (P < 0.05), minimal choroidal thickness (P < 0.05), macular choroidal thickness (P < 0.0001), and staphyloma depth (P < 0.0001)., Conclusions: The peripapillary area is tilted inferotemporally in 77.2% of myopic eyes. Peripapillary tilting was markedly greater in older patients. Greater tilt was associated with a thinner choroid, more extensive PPA, and deeper staphyloma.

Purpose: To investigate microstructural changes and visual prognosis in myopic subretinal hemorrhages (mSH) without choroidal neovascularization (CNV)., Methods: In this retrospective, observational case series, 13 consecutive eyes with mSH were followed for 6 months. The medical records, fluorescein angiography (FA), and spectral-domain optical coherence tomography (OCT) were reviewed. Fluorescein angiography confirmed the absence of CNV. The baseline and 6-month findings/parameters were investigated, including the maximal hemorrhagic height, intraretinal hyperscattering signal across the retina at 6 months (i.e., intraretinal hyperreflective sign), and integrity of the photoreceptor inner and outer segment (IS/OS) and external limiting membrane (ELM) lines., Results: The final visual acuity (VA) improved significantly (P = 0.001), and the hemorrhages resolved in 12 (92.3%) eyes by 6 months. The tops of the hemorrhages reached the outer nuclear layer (ONL) in three eyes (23.1%), internal limiting membrane (ILM) in five (38.5%), and between the two layers in five (38.5%). The intraretinal hyperreflective sign in all eyes extended into the ONL in five eyes (38.5%), to the ILM in four (30.8%), and between the two layers in four (30.8%). The location of the hyperreflective signs at 6 months coincided with the ruptured retinal layers at baseline in all eyes. The IS/OS line and the ELM were each intact in six (46.2%) eyes. The final VA was associated significantly with the IS/OS (P < 0.05) and ELM (P < 0.01) integrity., Conclusions: The intraretinal hyperreflective sign, presumed to be scarring that enters through the disrupted outer retina, is correlated closely with photoreceptor function.